.net try catch finally

Yesterday, dechu said he once read my blog. I then realize I have a blog... Almost forgot this place. Today I am going to talk about try, catch, finally.
Few years ago, I used try catch to avoid unexcepted error, and always put everything in a big try block. Catch the error, maybe print it out and that's it. This is a really bad practice.
I started to look at other people's code, and learned to do some clean up in finally block, however, this is still not enough. Now I started to use multiple level try & catch, in the lower level,
trying to rollover previous actions like a sql transaction in catch block, and then throw new exception to upper level code. This improve the error handling abilities and allow code structure to be easily handled. The disadvantage is the performance issue of throwing exceptions.
But considering we are not using exceptions mechanism to achieve certain result, the time consuming exception won't eat up resources in the normal run.

First look at this code below:

/ try-catch-finally
using System;public class TRYCATCHFINALLY
{
public static void Main ()
{
   try
         {
             Console.WriteLine("Executing the try statement.");
             try
             {
                 DoSomething();
             }
             catch (System.Exception sex)
             {
                 throw new SomethingFailedException();
             }
             Console.WriteLine("Now something done, try other things now.");
             try
             {
                 DoOtherthing();
             }
             catch (System.Exception oex)
             {
                 throw new OtherthingFailedException();
             }
             Console.WriteLine("Executing the try all done.");
         }
         catch (SomethingFailedException sfe)
         {
             Console.WriteLine("{0} Caught exception #1.", e);
         }
         catch (OtherthingFailedException ofe)
         {
             Console.WriteLine("{0} Caught exception #1.", e);
         }
         finally
         {
             Console.WriteLine("Executing finally block. Clean up
everything.");
         }
}
private void DoSomething()
        {
             try
             {
                 //Hello 6sb
             }
             catch (System.Exception e)
             {
                 //Rollover
                 throw new Exception WhateverException();
             }
             finally
             {
                 // clean up
             }
        }
private void DoOtherthing()
        {
             try
             {
                 //lv 6sb
             }
             catch (System.Exception e)
             {
                 //Rollover
  throw New Exception WhateverException();
       }
             finally
             {
                 // clean up
             }
        }
}

.Net 的优缺点

.Net === 一堆库+虚拟机

.Net + C# === Java + JVM

普遍觉得有以下优点：

1. MS主推

2. 支持多语言

3. .NET的核心虚拟机CLR将c#这种编译出来的CIL中间代码再编译成机器代码，而非jvm的解析，所以运行速度快

4. 安全，内存，异常处理都在虚拟机内得到一定的保证。

5. 跨平台ms没做，支持了一个叫Mono的项目，可以在Linux, Solaris, Mac OS X, BSD, HP-UX下面跑，不过现在也就做到.Net 2.0

 

我自己认为的好处：

1. 写完程序配置起来简单，基本上机器都会在自动跟新的时候装上这个.net runtime envrionment

2. 学起来容易，不管是web application还是desktop software，学了很大一部分能通用

3. VS用起来蛮舒服。

4. 跟sqlserver也结合紧密，甚至可以说跟ms的所有东西都结合紧密。

5. 开速开发GUI的首选吧。

6. 开发web service嗷嗷简单，客户端如果也用.net，API这块省力。

 

缺点:

1. 代码保护不容易，跟java似的。。

2. 更新太快，丫的3.0还好，3.5就是一个更新的平台，引进一堆没听过的东西。。现在已经出4.0了。

3. 跟人说会这么好像很没面子，不如gs的python来的野性。。。哈哈

4. 有些功能没有，要调用windows library里面的函数了，MFC能干的丫的managed code不一定能干，只能走unsafe code的路子，但是前面的优势就没那么明显了。

 

SQL Server Profiler fonts error

运行SQL Server Profiler，生成，连接数据库，正常，当点下run开始跟踪的时候，报错："only TrueType fonts are supported. There id not a TrueType font"。倒，微软还真进步，看来要淘汰windows中的非TrueType字体了。

避免该错误，需要修改Profiler的指定字体，方法如下：

点击 Tools菜单->Options...

然后在选项对话框开头的Display Options部分，"Choose Font..."换一种TrueType的字体即可，我比较喜欢Vendana 。

windows form c# -- User Interface tips to show system status

When a time consuming task is performed, we can either perform it using backgroundworker, or using a little tips like this:
Cursor.Current = Cursors.WaitCursor;
// Perform your task here
Cursor.Current = Cursors.Default;
From the UI perspective, User understand that the system is busy and will be more than happy to wait rather than disappointed.

General Linux Common Command

Generic Linux

COMMAND NAME		DESCRIPTION
df -h                   shows disk usage in human readable form
man <commandname>       shows more info about a command
uname -a		kernel release version
/usr/sbin/smbd -V	samba version
 /usr/sbin/httpd -v	apache version
mysql -v		mysql version
php -v		        php version
mv		        moves or renames a file
cp		        copies or backsup a file
rm		        removes or deletes a file
ps -ax|grep <process>	outputs processes running <process>
 ps -AH		        report process status
top		        shows processes
top -i                  shows only active processes
iptraf		        shows network info
mc -d                   show midnight commander to navigate through system easily
 cat /proc/mdstat	shows software raid
host -t mx aol.com	shows the mx records for aol.com
net groupmap list	shows samba mappings to nt groups
telinit 1		changes to single user mode
 ifconfig		shows detailed info on ethernet ports
grep -r "casesensitivesearch" *		finds all documents containing the criteria in a dir
tail -f /var/log/<LOGFILE>		realtime viewing of your log file
 hdparm -t /dev/mdx (where x is 0,1,2,etc)		shows software raid performance
mdadm --detail /dev/mdx (where x is 0,1,2,etc)		gives raid info
tar -czvf foo.tar.gz foo                               creates a tar/zip file of a directory
 tar -xvzf foo.tar.gz                                   untar/unzip a tar/zip file
scp -P <ssh_portnumber> foo.tar.gz <other_server_ipaddress>:/opt     transfers file to another server
rsync --progress -te "ssh -p <ssh_portnumber>" foo <other_server_ipaddress>:/opt     transfers file to another server
 sed -i s/foo/fee/g <FILENAMEORPATHTODIR>  replaces foo with fee

vc++ compiler support Ecma c++ standards

Visual C++ complies with these standards:

• ISO C 95

• ISO C++ 98

• Ecma C++/CLI 05

-----------------------------------------------------------------------------

The GNU C library is compatible with the C standard adopted by the American National Standards Institute (ANSI): American National Standard X3.159-1989---"ANSI C".
The header files and library facilities that make up the GNU library are a superset of those specified by the ANSI C standard.

segmentation fault in linux/unix

A wired error happened today when I am trying to run a gcc complied application.
"Segmentation fault" happened in the least expected place (at least according to cout, it paused), so I tried very hard to
modify this bit of code in many ways. I couldn't solve the problem until I tried gdb.
After reading wikipedia for the simplest way of using gdb, and few other articles on the web, I start to debug the code.
I find that the application had a bug in one line, which is way below the code that I was messing around. 
How stupid I am... I should know that the application is still running and cout just haven't finish printing.....
I should have turn to debugging straight away because this is c++, not c#.

Conclusion: Never trust manual debug using cout.

Thesis --- Infrastructure Development for a Mind Attention Interface

Chapter 1
Introduction
For a long time, people have dreamt of using their mind as direct input to control
machines. Researchers on Brain-Computer Interfaces (BCIs) have been working
to build practical systems which can be used by disabled people and there have
been significant results which show that computers can be slowly but effectively
controlled by a human mind [1, 63]. "Mind" here refers to the combination
of thought, emotion, perception, imagination, and other brain states. In the
Mind Attention Interface (MAI), we intend to measure mind states by using
Electroencephalograms (EEG).
For some time, psychology and neuroscience researchers have had a research
focus on attention. Attention is the cognitive process of selectively concentrating
on things that the mind is interested in [35]. It is one of the cognitive processes
which is considered as having a most concrete association with the human mind,
and it is closely linked with perception [40]. Audio and visual cues for attention
are another source that we can use to help improve communication with
computers. In the MAI, measurements of attention such as gaze, head or hand
movements are obtained from dedicated recording systems.
The idea of the Mind Attention Interface is to create a platform for interacting
with a virtual reality theatre using EEG and measures of attention. This thesis
describes the construction of such extensive hardware and software platform,
1
2 CHAPTER 1. INTRODUCTION
which is called the MAI System. The rest of this chapter introduces the most
important concepts behind the Mind Attention Interface.
1.1 Brain-Computer Interfaces
1.1.1 Background
A Brain-Computer Interface (BCI) is an interface between a person's brain and
a computer. It is a computer interface that only uses signals from the brain,
and which does not require any user motor activity [2] such as eye or other body
potentials. Research on BCIs started in the 1970s and have developed rapidly
in the 1990s [25]. BCIs can be classified in two major categories: invasive and
non-invasive. In invasive BCIs, electrodes are implanted into the brain during
neurosurgery, and these systems diagnose and repair damage brain functions.
(Invasive BCIs will not be discussed further in this thesis) Non-invasive BCIs, on
the other hand, detect brain signals from the surface of the brain, such as the
scalp of a user, using an electrode cap. Electroencephalography (EEG) is the
most commonly used non-invasive BCI due to its fine temporal resolution, ease
of use and cost [63]. By converting the acquired analogue signals to digital, and
sending them to a computer for processing, a BCI can be used to control certain
electronic devices.
1.1.2 Electroencephalographic BCIs
The first electroencephalogram (EEG) recording was obtained by Hans Berger
in 1929 [19]. An EEG is a graph of measurements of the electrical activity of
the brain as recorded from electrodes placed on the scalp or on the cortex itself.
Because electrical activity is closely involved in the way the brain works,
EEG provides "direct measurements" of brain functions in comparison with technologies
which rely on blood flow or metabolism which maybe decoupled from
brain activity. Traditionally, this non-invasive technology has several limitations:
1.1. BRAIN-COMPUTER INTERFACES 3
Firstly, scalp electrodes are not sensitive enough to pick out action potentials
of individual neurons. Instead, the EEG picks up signals from the synchronised
groups of neurons. Secondly, identifying the source locations of measured EEG
potential is an invoice problem which means that these desired locations are very
non-specific. In contrast with other brain-imaging techniques such as functional
magnetic resonance imaging (fMRI) , the spatial resolution in the region could
be less than 3 millimetres. Thirdly, due to its susceptibility to noise, this method
can be largely affected by the surrounding environments, such as the 50Hz AC
noise (50Hz is the mains power frequency in Australia). On the other hand, EEG
has several positive aspects as a tool of exploring brain activity. As mentioned
above, it is an affordable system for most research groups. The setup and scalp
preparation for modern EEG systems is relatively straightforward to use. In particular,
its temporal resolution is very high. EEG has a time resolution down to
sub-milliseconds compared with other methods for researching brain activities,
which have time resolution in the order of seconds or even minutes.
The types of waves measured in the EEG signal are studied together with
mental states. Major types of continuous, sinusoidal EEG waves are delta, theta,
alpha, beta, and gamma. The only difference between these signal types is the
frequency range † . They are listed in Table 1.1 with associated mental states.
Electroencephalographic BCI applications can provide disabled users with a
new channel for sending messages to the outside world [66]. In [23], slow cortical
potential (SCP) was used to control cursor movements on a computer screen.
This rhythm shows up as large drifts in the cortical voltage which last from a few
hundred milliseconds up to several minutes. In [66], similar cursor movement BCI
is implemented by controlling the amplitudes of the sensorimotor activity signals
such as the mu rhythm in the alpha frequency band (8 -12Hz). Other commonly
Functional fMRI is the use of magnetic resonance imaging to measure the haemodynamic
response related to neural activity in the brain. MRI is a non-invasive method used to render
images of the inside of an object.
†There is no precise agreement on the frequency ranges for each type.
4 CHAPTER 1. INTRODUCTION
wave frequency range associated mental states
Delta 0-4 Hz certain encephalopathy, deep
sleep
Theta 4-8 Hz trances, hypnosis, lucid dreaming,
light sleep
Alpha 8-12 Hz relaxation, calmness, abstract
thinking
Beta 12+ Hz anxious thinking, active concentration
Gamma 26 - 100 Hz higher mental activity including
perception, problem solving, fear,
and consciousness
Table 1.1: EEG waves associated with mental states [13]
used signals in BCIs are Event-Related Potentials (ERPs), Visual Evoked Potentials
(VEPs), and Steady State Visual Evoked Responses (SSVERs) [64, 65].
Among these signals, an ERP response to unpredictable stimuli called the
P300 (or simply P3) is one of the most robust [11]. The P300 ERP appears as
a positive deflection of the EEG voltage at approximately 300ms. Based on this
phenomenon, P300 character recognition is designed in [14] to choose characters
for disabled users: A 6 × 6 grid containing alphabet letters and numbers is
displayed on screen and users are asked to count the number of times the row or
column flash which contains the character they wanted to select. Every twelve
flashes are called a set, which all rows and columns have flashed once. P300
amplitude is measured and the average response to each row and column is used
to determine the selected character.
Although there are many existing BCI systems in use at present, the extensive
training required before users obtain such technology and the slowness in com1.2.
ATTENTION AND THE MIND AS A COMPUTER INTERFACE 5
munication is the substantial barrier of using BCI systems. One implementation
by Wolpaw in [65] using mu rhythm achieved 10.88 binary decisions per minute
with 2 month training. In another word, a typical cursor move from the centre of
a video screen to a target located at the top or bottom edge will take 3 seconds.
Another example would be P300 character recognition system implemented by
Donchin in [11], which achieved 9.23 binary decisions per minute online classification
rate. The classification rate is the way BCI uses to compare the speed
of the system. In P300 for example, more than five binary decisions (correct
ones) are needed to choose a single symbol as there are totally 36 symbols. To
summarise, users are normally trained through biofeedback for several weeks to
months before they make use of the systems, and online classification rate are
less than 15 binary decisions per minute [47].
1.2 Attention and the Mind as a Computer In-
terface
1.2.1 Attentive Interface
The so-called "Attentive Interface" is a relatively new category of user interface,
which dynamically prioritises the information it presents to its users [58]. In
[46], Selker gives a definition of Attentive Interface as: "Context-aware human-
computer interfaces that rely on a person's attention as the primary input". Here
attention is epitomized by eye gaze which is one of the key features that have
been widely used in Attentive Interfaces. Figure 1.1 shows a typical eye-gaze
tracking system. In recent years, interactive applications using eye tracking have
improved to the stage that they now allow people to type, draw, and control
an environment[26]. In these interfaces, the synchronised rotation of the eyes is
often used as a pointing device to point to and select a graphical object located
at the intersection of the eye-gaze vector and the screen (see [52] for example).
6 CHAPTER 1. INTRODUCTION
Blinking, eye gestures and movements, as well as eye dwell-time can all be used
in selection and control [56]. At present, training is essential to use attentive
interfaces because none of the above methods is natural. Some experts believe
that ongoing research may bring us generation interfaces with more natural eye
movements for selection and control [38].
Figure 1.1: Gaze system by SeeingMachinesTM
1.2.2 Mind and Attention for Interaction with a Virtual
Environment
In virtual environments, real-world human movements can be mapped to actions
in a virtual world. The effect of these actions is often to do with manipulation
of the entire objects in 3D spaces. Although most emphasis has been placed
on physical controllers together with tracking systems, eye gaze has also been
considered as an interface to a virtual environment [18]. Tanriverdi and Jacob,
in [52], claim that eye movement-based interaction offers the potential of easy,
natural, and fast ways of interacting in virtual environments. A comparison of
the performance that eye movement and pointing based interactions in virtual
environments was undertaken, and the results show that eye gaze based technique
has speed advantage especially in distant virtual environment.
1.3. THIS THESIS 7
Bayliss in [3, 5] demonstrate examples of EEG based BCI systems in control
of virtual environments. Her past research in [4] also gives us a clue of the effects
that eye tracker and virtual environment impact on EEG recording, and the
results indicate that neither eye tracker nor virtual environment will introduce
significant noise than computer monitors to the EEG signal quality. Therefore,
the Mind Attention Interface idea seems realistically, which all devices would
work together without affecting others.
My infrastructure goal was to build a fundamental framework for Wedge virtual
reality theatre that supported mind and attention data from different sources,
in different formats, and which would go beyond a simple BCI interface. Firstly,
the real-time analysis of brain states from EEG was planned to be quite sophisticated
and to go beyond a simple classification of signals into frequency bands.
Secondly, it was planned to provide natural feedback of a user's brain states to
the evolution of an immersive virtual experience which included 3D graphics and
surround sound. Thirdly, the measurements of eye-gaze-based attention from a
user in virtual environment were intended to provide feedback on the brain state
of a user. Eye gaze can also play a role in filtering EEG signals for interference
from oculomotor events. Head position, orientation, and other control devices can
also be used to interact with the virtual world. Figure 1.2 shows the feedback
loop that we intend to create in the MAI.
1.3 This Thesis
This thesis describes infrastructure development for a "Mind Attention Interface".
This Mind Attention Interface enables sensor measurements of a subject's mind
states and attention states to be used as control and feedback data for a virtual
environment. Sensor devices measure EEG brain activity, eye gaze, and head and
hand movements. The MAI has been built for use in the Wedge, a two-walled
immersive virtual environment which combines stereoscopic computer graphics
with surround sound. Its goal is to contribute to Human Computer Interface
8 CHAPTER 1. INTRODUCTION
Figure 1.2: Feedback loop in the MAI
(HCI) and Brain-Computer Interface (BCI) research in virtual environments,
and, by so doing, provide new insights into the human behaviour and the human
mind.
The infrastructure of the MAI described here consists of four major layers:
The first layer is the Data Acquisition (DAQ) layer which handles the device
drivers, data transmission over the network, and timing. The second layer is a
central server that handles peer connections, header information and provides the
application layer clients with a gateway to access data over the network. The third
layer is the signal-processing layer, which processes raw data and provides highlevel
information for further usage. The Spectral Engine Connection Kit (SECK)
enables multiple processing modules to be used in this layer and thus distributes
processing over the network. The last layer in the MAI is the application layer
that connects to the MAI and display information in the virtual environment.
My major contributions are the MAI System, which include first and second
layers and software libraries created for the fourth layer. Although the signalprocessing
layer is largely the work of others, its interfacing components are also
1.3. THIS THESIS 9
a contribution of the present thesis.
When I commenced this project, the MAI had just been funded and no MAI
infrastructure existed. In the last one and half years, my research has included
the investigation and purchase of hardware, and the development of software for
the MAI framework. This thesis describes my research process: System hardware
and associated software are described in Chapter 2. Chapter 3 specifies
the MAI System software platform requirements and states the studies over a
set of comparable systems. Chapter 4 contains a discussion of the MAI software
design considerations based on the requirements. Chapter 5 describes the implementation
of the system enabling components. Utilities that create supportive
environments for carrying out experiments are also described in Chapter 5. Subsequently,
profiling results of the current system performance in comparison with
another similar system are shown in Chapter 6. Overview of this project and
future work are summarised in Chapter 7.

残缺的回忆录

2002年5月2号----2003年5月6号 回忆录

作者：杨振

5月2号 天气晴

那天我还是起得很早，一大早就去接平和心。那天平好像有点生气了，当然是生我没有去接她了。我也没办法啦，妈妈的话我还是要听的，而且正好碰上那几天脚伤到了。所以嘛，将功补过咯。我去的时候他们还没有起，我就在外面等了一下子，好像还带了一本书，不知道为什么要装正经。那里还要看书嘛，不就是痛痛快快的玩几天嘛。天气好像很好的样子，而且甚至有一点冷，接完他们我们就去了我的房间。那天黄晶那头猪是没有起的，我们收拾好了然后去叫他，发现他还在睡猪觉，所以说嘛，人不可貌相，别看是甲鱼，还很会睡觉的呢。我们好像是去了八食堂吃包子，嗯，就是我前面提到的神奇的包子了。这里唯一特别的就是特别难吃，比起南昌，上海的包子，我也不能再用言语描述了。反正这是我吃了一年的包子，这种朴实无华的包子代表了清华包子界的最高水平啊。。。五个人，当然要把桌子拼到一起了，在八食堂拼桌子，这么大胆的事，我还是第一次干哦。徐涛还是很会吃，吃了很多包子的。其实也要多吃一点包子，因为那天我们的计划就是去有"南昌步行街"美称的王府井了。说到王府井，当然啦，我是没有直接去过，都是坐车到西单，然后步行前往的。（这个步行可是大有讲头，等一下我慢慢的分解）这里的西单也是很有名气的，这里我也给他一个名字"南昌中山路"，哈哈，不是夸奖啦，这两个地方都很繁华的哦。
吃饱了，喝足了，好，现在开始我们一天的行程吧。

随着一声号令，五位运动员出发了，今天的旅途可谓是遥远而艰辛，虽然很辛苦，但失去充满了欢笑哦。
路线是由我订的，从南门出发，坐xxx路车可以直接到西单，只可是轻车熟路，我都去过n趟了。路程大概是一个小时，不知道车上有没有位子哦。反正我是没机会坐了。不过总的来说还算顺利，我们很快的就达到了目的地。哈哈，下车以后当然是耳目一新了，我是看过好多次了，一家手机大卖场，几家百货大楼，也就是那个样子嘛，而且里面特别像万寿宫，我都开始怀疑北京人的生活水平了。难道这种地方也是你们的商业中心？不说这些废话，当然我们就开始了漫无目的的逛商店。我虽然是个男孩子，逛商店这种mm活动我也是乐此不疲啊。都有意思啊，多好玩啊，多有趣啊，多变态啊。。。逛啊逛，逛啊逛，我们就慢慢的前进，慢慢的消耗体力，慢慢的累的不行了。我们已经基本上遍历了从西单到天安门（也就是长安街）上所有的大商场哦。
    就在这个时候，一件很恐怖的事情终于发生了。天啊，恐怖的我都不想再打开起那段尘封已久的回忆。哈哈，恐怖吧，一听就很恐怖吧。嗯，然后呢，我们就。。。呵呵，是不是真得很想知道呢？好吧，我就勉为其难的告诉你们吧。记得开始提到步行吗？故事就是从这里讲起的。

C++ Read Binary File and convert char * to float

I recently need to write a c++ data reader. The data reader reads a file while is in binary format, and every four byte should be convert into float. I found it very easy to read file, you only need to specify ios::binary when reading. This is a bit different from c#. If you don't define ios::binary, you will get unexpected eof in the middle of the file. With regards to conversion, there are 2 possible ways. First, memcpy which is slow and time consuming. You can also do reinterpret_cast. For example:
char* tmp = new char[sizeof(float)];
float val = 0;
memcpy(tmp, val, sizeof(float));
val = *reinterpret_casttmp
This should give you some idea on how to handle binary file read. The following is the complete example, might not suit your situation though.

#include 
#include 
#include 
#include 

using namespace std;
#define interval 400

class Data {
 public:
  float** data;
  Data (const string& file);
};

Data::Data (const string& dataFile) {
 ifstream file (dataFile.c_str (),ios_base::in|ios_base::binary);

 string line;
 int file_length = 0; 

 file.seekg(0,ios::end);
 file_length = file.tellg();
 file_length -= 19;
 file.seekg(0,ios::beg);

 this->data = new float* [file_length/4];
 for (int i =0 ; i< file_length/4 ; i++)
 {
  this->data[i] = new float [3];
 }

 // Read Header File, Basiclly Ignore It.
 char* header = new char[19];
 file.read(header,19);
 
 int t = 0;
 char* acc = new char[12*interval];
 // Read Actual Data;
 while (!file.eof())
 {
  file.read(acc,12*interval);  
  int read_length = file.gcount()/12;
  
  for (int k = 0 ; k < read_length ; k ++ )
  {
   for(int j=0;j<3;j++)
   {
    this->data[t+k][j] = (*reinterpret_cast(acc+12*k+4*j));
   }
  }
  t += read_length;
 }
}

遗弃在时间角落里的博文系列之-----人生凄苦

我总算知道了人生凄苦的来历。
人生七苦

生、老、病、死、怨憎会、伤别离、求不得。

轮回. 业力.因果. 彼岸. 度. 贪. 嗔. 痴.

《般若心经》
[唐]玄奘法师译

观自在菩萨，行深般若波罗蜜多时，照见五蕴皆空，度一切苦厄.

舍利子,色不异空,空不异色；色即是空,空即是色。受、想、行、识，亦复如是。舍利子，是诸法空相：不生、不灭；不垢、不净；不增、不减。是故空中无色。无受、想、行、识；无眼、耳、鼻、舌、身、意；无色、香、声、味、触、法。无眼界，乃至无意识界；无无明，亦无无明尽；乃至无老死，亦无老死尽。无苦、集、灭、道。无智亦无得，以无所得故。菩提萨捶，依般若波罗蜜多故。心无挂碍，无挂碍故。无有恐怖，远离颠倒梦想、究竟涅磐。三世诸佛，依般若波罗蜜多故。得阿耨多罗三藐三菩提。

故知般若波罗蜜多，是大神咒，是大明咒，是无上咒，是无等等咒。能除一切苦，真实不虚。故说般若波罗蜜多咒，即说咒曰：“揭谛！揭谛！波罗揭谛！波罗僧揭谛！菩提萨婆诃！”

“色即是空”我简单的理解就是：色即是虚无，虚无就是色。色即是空，指世上的色，欲望等都是虚幻的，空无的，等你真的视一切为空无，就发现虚幻就是和色一样了。

就像你孜孜以求的某种东西，迷恋追逐到无药可救的地步，但是历经劫难后反思，其实你追求的只是一场虚幻，虚无，欢情过后，什么都没有，所谓色即是空。

看破红尘之后，你明白空和色没什么区别，空不异色。你就安心的沉于你的“空”的哲学中。

所谓四大皆空。



谈苦之余，玩了下黑板报推荐的东东，发现俺的名字roy pk 不过 dan 和 james.

遗弃在时间角落里的博文系列之-----老师

呵呵，不知怎么的，脑子里一直挥之不去刘庸这篇和老师争论的文章。

从生下来到现在，接触的人并不多，家人，老师，同学（一度关系），朋友（二度关系的），同事，陌生人。这么排列下来，老师还确实是很重要的一个组成部分。我一直对六度理论深信不疑，能作为一度关系存在的肯定是上辈子的缘分了。那等我一个一个数来。

幼儿园：好像是肖老师？这个已经不太确定了，只是母亲常常提起在菜场碰到了之类的事情，每次提及，又必然会说，俺第一天不肯上幼儿园，还打了老师一个耳光的不光彩之事。现在想来，还多亏了肖老师，不然也不会让我早一年就去上学，这样我就错失了结识现在这些同学的机会了。中国的古话说，三岁看大，七岁看老，肖老师是真的看到我的未来吗？

小学：小学时最幸福的时代，在另一个肖老师的帮助下，垮地段的进了南昌市百花洲小学。肖老师是我的数学老师，我的班主任黄老师是现在南昌市教委的重要任务了。那时的黄老师才刚刚毕业，很年轻，现在想来可能比我还小，带着大家一起走了4年，后来离开了我们发展前途去了。五年级的时候来了个王老师，隐约记得王老师年级很大。最近一次见到肖老师和黄老师是高考的谢师宴。记得小时候常去黄老师家里上课，学语文竞赛的东西，黄老师家的小狗特别可爱，那是我唯一喜欢的小狗了。 小学还有很多好朋友，这里就不提他们了，只是写的时候，忍不住要停下来想想。

初中：老实说，初中我还不算特别优秀，特别是刚进校，被班主任和数学老师和起来欺负了一通，后来班主任病了，换上了新的班主任徐老师，现在还有联系。当然，数学老师李老师现在估计也退休了，在她的印象里，我估计至少没有刚入学那么坏，但也不至于太好，清晰的记得数学考100分的时候，李老师揪着我的耳朵。。。哎，一个当初被他誉为“从小炸干了油”的学生，也毕竟不大可能有如此的成绩，只是她判断的太早了些。初中一直是个进步的过程，老师对我的关怀也是日渐增长，我这颗苗子真要谢谢初中的这些老师了。这里想特别提下物理老师，这个是和我最投缘的老师，陈老师的教学方法让我对物理的兴趣超过了一切，当然，后来还有化学老师肖老师的推波助澜，让我直奔理科的方向。语文老师周老师没太多印象了，大眼镜，娶了我们的政治老师，政治老师怀孕了之后，换了个超级搞笑的陈老师，还兼代办学校食堂，听陈老师一节课，基本上就是笑一节课。体育老师已经忘了叫什么，历史老师好像和排球队有点什么联系，而美术老师应该是个叫图什么的老师，反正大光头，很有气势。

高中：高中又重演了初中时换班主任的闹剧，化学老师游老师只教了我们短短3个月。这段友谊一直在我们这个小圈子里面维系到大二。走马上任的肖老师对我的人生气了很大的帮助，至于后来换到一中之后，OBB熊老师接任，也让我伤心了好久。刚开始有个非常闹心的物理老师，总觉得我们班物理不够好，老拿难题刁难我，拿我们和四班比，那时就很羡慕一班和三班的物理老师，娇弱的可爱（男的，男的）。分班之后我如愿的得到了这个娇弱的物理老师，哈哈，虽然可能实力不如我。隔壁班有漂亮的化学老师，而我们班的肖老师却也对我胃口，虽不是美女，但绝对是好老师。语文老师是俺的心头痛，我除了考试还算对得起老师的栽培，文学方面是沾不上边了。数学老师应为叫多了外号，现在也只知道叫 “嬷嬷”，还有 “土拨鼠”。嬷嬷是对我评价和期望极高的老师，土拨鼠是数学天赋不错的一个老师。几乎解除了外国语学校所有的英语老师，比如徐明珠老师，就最喜欢我了，不过后来好像还有了其他宠爱，比如boggar。徐柯老师虽然是我的初中英语老师，但是我的英语基本上从她那里学的，当然，初中时还有几个不知名的老师，对我的帮助也很大。赵老师在高中的时候安排俺做过主持，可是俺天生好动，虽然口语相貌还过得去，但毕竟不是这块材料。

大学：大学的老师就太多了，每门课都有老师，但有两个固定的老师，一个是自己，一个是俺大哥。大哥是个超级天才的人，对我的帮助不下于老师。最后一次见大哥是在离开北京的前一个晚上，我陪大哥去买火车票。那次居然没有哭，我是个爱哭的人，想必可能是那段时间离别的经历太频繁，麻木了。现在真后悔了，哈哈。现在还能记起的老师不是爱上课讲笑话，就是容易发飚，或者是考试特别变态的。想来清华的老师也不过如此。

极力想回忆起每一位老师，极力想每个老师只公平的写上一句话而已。其实文章再长些，夹杂些故事，夹杂些朋友，夹杂些生活，那就是我的童年了和少年了。认识我的人，想必也只认识一个时间段的我，恐怕连kelly也不一定知道这些东西，今天一股脑全部写了出来，算是把老照片扫描到电脑数字化吧。我各段时间最要好的朋友在我的脑海里，也有区域的空白。只知道kelly小时候很会胡闹(现在也是很胡闹。。)，像个小男孩。甘心和我接触的久点，但小时候啥样就不知道了。平姐姐初中的时候啥样啊？你写了顺带把hj,乔文，徐涛通通一道跟我讲讲吧。徐坤和大哥都是大学才认识的，但想必以前也是叱咤风云的人物，可惜这两位爷是没工夫写这个了。两位要来澳州的年青人不知道看不看俺的blog,jenny俺知道的不少，但好像大学的生活就空白了，不过她肯定要说，我自己也觉得空白。。罗曼是个初中可漂亮了，估计小学更漂亮，也好久没有联系了。让jennifer写绝对就是我小学的时候吃了这个，吃了那个（别打我）。。。

当然，最想知道的还是现在大家过得都好，呵呵。

遗弃在时间角落里的博文系列之-----地球村

这个世界说大不大，有了网络，有了通信方式的进步，大家紧密地联系在一起。一条网线，一根电话线就可以把大洋彼岸的你我他交织在一起了。

这个世界说小也不小，不管是汽车、火车，甚至飞机，要从这里回到我的故乡，又何尝不要长途跋涉奔波劳累一两天呢。

在电脑里找出一本旅游的书，津津有味的看着，最有意思的不是祖国大江南北的名胜古迹和山川河流，也不是各地的风土人情，确实家乡的点点滴滴。 “鄱阳湖的草，南昌人的宝”， 绳金塔的南昌米粉， 就留那南昌火车站的黑司机，我都丝毫没有厌恶的情绪了。

虽然离家不久，但细算来，加上大学四年，南昌给我的印象还只是停留在南昌一中和外国语学校的学生生活阶段，仅此而已了。每次回家看到家乡的变化，就觉得自己都快跟不上时代了，要努力了。

最后以滕王阁序结束吧。

滕 王 阁 序 王 勃
豫章故郡，洪都新府。星分翼轸，地接衡庐。襟三江而带五湖，控蛮荆而引瓯越。物华天宝，龙光射牛斗之墟；人杰地灵，徐孺下陈蕃之榻。雄州雾列，俊彩星驰。台隍枕夷夏之交，宾主尽东南之美。都督阎公之雅望，綮戟遥临；宇文新州之懿范，［衤詹］帷暂驻。十旬休暇，胜友如云。千里逢迎，高朋满座。腾蛟起凤，孟学士之词宗；紫电青霜，王将军之武库。家君作宰，路出名区。童子何知？躬逢胜饯。
　　时维九月，序属三秋。潦水尽而寒潭清，烟光凝而暮山紫。俨骖［马非］于上路，访风景于崇阿。临帝子之长洲，得仙人之旧馆。层峦耸翠，上出重霄；飞阁流丹，下临无地。鹤汀凫渚，穷岛屿之萦回；桂殿兰宫，即冈峦之体势。
　　披绣闼，俯雕甍。山原旷其盈视，川泽纡其骇瞩。闾阎扑地，钟鸣鼎食之家；舸舰迷津，青雀黄龙之舳。虹销雨霁，彩彻区明。落霞与孤鹜齐飞，秋水共长天一色。渔舟唱晚，响穷彭蠡之滨，雁阵惊寒，声断衡阳之浦。
　　遥吟甫畅，逸兴遄飞。爽籁发而清风生，纤歌凝而白云遏。睢园绿竹，气凌彭泽之樽；邺水朱华，光照临川之笔。四美具，二难并。穷睇眄于中天，极娱游于暇日。天高地迥，觉宇宙之无穷；兴尽悲来，识盈虚之有数。望长安于日下，指吴会于云间。地势极而南溟深，天柱高而北辰远。关山难越，谁悲失路之人；萍水相逢，尽是他乡之客。怀帝阍而不见，奉宣室以何年？
　　嗟乎！时运不齐，命途多舛。冯唐易老，李广难封。屈贾谊于长沙，非无圣主；窜梁鸿于海曲，岂乏明时？所赖君子安贫，达人知命。老当益壮，宁移白首之心；穷且益坚，不坠青云之志。酌贪泉而觉爽，处涸辙而犹欢。北海虽赊，夫摇可接；东隅已逝，桑榆非晚。孟尝高洁，空怀报国之情；阮籍猖狂，岂效穷途之哭？
　　勃三尺微命，一介书生。无路请缨，等终军之弱冠；有怀投笔，慕宗悫之长风。舍簪笏于百龄，奉晨昏于万里。非谢家之宝树，接孟氏之芳邻。他日趋庭，叨陪鲤对；今晨捧袂，喜托龙门。杨意不逢，抚凌云而自惜；锺期既遇，奏流水以何惭？
　　鸣呼！胜地不常，盛筵难再。兰亭已矣，梓泽邱墟。临别赠言，幸承恩于伟饯；登高作赋，是所望于群公！敢竭鄙诚，恭疏短引。一言均赋，四韵俱成。请洒潘江，各倾陆海云尔。

　　滕王高阁临江渚，佩玉鸣鸾罢歌舞。画栋朝飞南浦云，珠廉暮卷西山雨。闲云潭影日悠悠，物换星移几度秋。阁中帝子今何在？槛外长江空自流！

遗弃在时间角落里的博文系列之-----蜘蛛

昨天晚上11点本来打算睡觉，上楼发现窗子上好像有只螃蟹，还觉得奇怪，走进一看，原来是只蜘蛛，身体巨大，这还是第一次看身体这么大的蜘蛛。

有些害怕，后退了几步，做了蛮久的心理斗争，武装了起来，硬着头皮给消灭了。也不知道是什么物种，有没有毒。

刚才还在网上搜索了些蜘蛛的图片，发现这个帖子说的很恐怖，还好俺没碰上上面这些。
世界最具毒性的蜘蛛欣赏
下面科普下蜘蛛，昨天还照了打死的蜘蛛的照片，活的不敢照，怕惊吓了，不好打了。


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蜘蛛，节肢动物，蛛形纲，蜘蛛目动物的统称。有3.5万多种,遍布于全世界，中国已发现的有2000多种。外形特征是8只脚，身体呈圆形或长圆形，分为头胸部和腹部，中间有细的腹柄相连。蜘蛛长有触须，雄蜘蛛的触须长有一精囊。

　　蜘蛛多生活在屋檐下或草木中。它肛门尖端的突起能分泌粘液，这种粘液一遇空气即可凝成很细的丝。蜘蛛以昆虫为食，它常在不易被破坏的旮旯、树梢、草丛以及昆虫时常出没的地方结出一个八卦形的网。比如金园蛛的体形较大，它的网粘性极强，连重量轻一些的鸟都会被它的网粘住。平时，尽管蜘蛛不在网上，但网上的细丝总有一根连通着蜘蛛休息的地方，昆虫只要一触网，蜘蛛就会获得信息。对粘上网的昆虫，蜘蛛都会先咬上一口。这一咬，昆虫就被注入了一种特殊的液体棗消化酶。这种消化酶能使昆虫昏迷、抽搐、直至死亡，并使肌体发生液化，变成“一听液体的高蛋白罐头”。

　　蜘蛛种类很多，性质千差万别，但大部分都是“恶妻吞夫”的。母蜘蛛性成熟后，身上会发出一种特别的气味。雄蜘蛛嗅引这种气味后，就会迅速到母蜘蛛结的网上“求爱”。母蜘蛛对上网求爱的雄蜘蛛咬上一口，这样，雄蜘蛛也像撞网的昆虫一样，刚做完爱就成了母蜘蛛口中的美味佳肴。

　　澳洲的悉尼城，有一种黑色的蜘蛛，叫做“悉尼蜘蛛”。它只产在悉尼及郊区。它是迄今发现的对人类最危险的生物之一。它和红背蜘蛛、史氏王蛛分泌毒液的毒性没什么两样。

　　悉尼蜘蛛分泌的毒液可致人于死命；但对老鼠和有些昆虫等小动物则几乎失效。人一旦被它咬了以后，不出半个小时就会死掉；但有些昆虫和老鼠被咬后，却安然无恙，这是什么缘故呢？至今仍然是个谜。

　　世界各地生活着各种各样的蜘蛛。在南美洲亚马逊河流域有一种毛蜘蛛，它的可怕之处就是能与植物合谋吃人。日轮花的枝叶有着很强的缠性，人一旦触到日轮花就会被死死缠住，这时，成群的毛蜘蛛就会涌上来将人慢慢吃掉。与其相反，在澳大利亚有一种猎人蛛，它专吃蚊子并有着高超的捕蚊本领，被人亲切的称为“梦乡卫士”。

　　在美国，有一种会唱歌的蜘蛛，它通过上下颌的相互磨擦，就会发出一种奇妙的声音，好像唱歌一样。伦敦一位名叫哈斯威尔的百货店老板，专门养了两只能看守店门的毒蜘蛛。其毒性很强，被它刺中，轻者剧痛终日，长期不愈；重者就会一命呜呼。这两只蜘蛛看门，商店极为安全保险。

　　在圭亚那有一种食鸟蛛，它长达9厘米，体重60余克，八只脚张开有25厘米多宽。身上长有很硬的毛，还有八只眼睛。它结的网很坚固，经得住30多克的重量，小鸟只要被网粘住，就无法脱身。在巴布亚新几内亚有一种会织鱼网的蜘蛛，它吐出的丝非常结实又不怕水，当地居民就让蜘蛛把丝吐在藤筐上，取下后即可做鱼网捕鱼使用，十分耐用。

　　危地马拉有一种叫“司塔乌利维”的蜘蛛，有鸽子蛋那么大，它们常常几十只聚在一起，吐出一种比蚕丝还粗还亮的彩色蛛丝。结的网呈方形，中间有八卦图案，红红绿绿非常好看。当地居民很爱把这种蜘蛛网当作窗帘挂在窗户上。也有一种蜘蛛不会结网，但它会把吐出的丝滚成许多圆球挂在自己的螯肢上，每当小昆虫飞来，它就将丝球投出，还真是百发百中呢？

　　目前，据科学家研究试验，一束由蜘蛛丝组成的绳子比同样粗细的不锈钢钢筋还要坚强有力。它能够承受比钢筋还多5倍的重量而不会被折断。虽然一些蜘蛛丝细如头发，但你可别轻视它的能力和作用！蜘蛛丝非常富有弹性，一条直径只有万分之一毫米的蜘蛛丝，可以伸长两倍以上才会拉断。因此，我们可以说，蜘蛛丝是世界上最坚韧的东西之一。

　　由于蛛丝有着极佳的特性，所以蜘蛛可以用来防治害虫。而且，蜘蛛的结网行为在捕食动物中绝无仅有，属于比较特殊的类群。科学家正在研究和开发这一领域，让它在人们的生活中发挥作用。您想了解更多的蜘蛛吗？那么，您不妨来北京自然博物馆，参观一下我们的动物展厅，您就将会了解到更多的知识！

遗弃在时间角落里的博文系列之-----小年

陶喆的一曲沙滩，让我开始苦思冥想，有什么方法可以让自己真的忘记？

当年佛祖释迦牟尼在菩提树下修行，找寻生命的意义，21世纪的我，做在电脑前，仿佛体验了佛祖当时那看似庸人自扰的行为。

没有什么方法可以真的忘记，不过把得失看的轻如鸿毛，只不过把自己捧得高高的，那一切就会变得渺小。

今天是小年，其实我不想忘记，不过没什么气氛，就像拿着刀叉对这大雨大肉，总觉得少了什么。朋友估计现在在家的没几个，不是远在他乡，就是飞跃大洋。大家为什么不想想，是得不到的最宝贵，还是失去的最宝贵？不要进了我的圈套，其实我们拥有的最宝贵，不要为了一些欲望而欺骗，不要为了欲望而忘记自己其实已经有很宝贵的财富，迷失自己之后，回头看看自己走的路是否值得。

今天是小年，其实我很开心，虽然没有气氛，但有自己下厨，可口的饭菜不输给我吃过的美味佳肴。朋友都在为自己的理想奋斗，废寝忘食者，疲于拼命者，我自己看着自己走过的轨迹，一条坦途伴随着弯弯曲曲的岔道，总归还是走了过来，我也能预计这条路将走向何方。黄磊在似水年华中说，现在的年轻人，总觉得自己看得有多透，有多彻，其实透彻不在于能看到多深，只在于现在有一个好的心境。

小年快乐，小年一过，就是春节了，盼来了小年就盼来了希望，因为明年会更好。

遗弃在时间角落里的博文系列之-----读书心得

股票研究了半本书，还不想拿到桌面上来提，最近的外汇突变让我觉得很无辜，嗯，还是太贪了，金价的投机催高了澳元，却没有料到区区那么点利润就止步不前了，看样子国际大鳄们全然超过了我的想象，属于理智加技术型，不像咱们国内的庄家，贪得无厌还没有技术含量。哈哈。

因为想参加一个市场营销（Marketing）的组织，开始研究经济管理方面的资料，其实以前也就一直在看，在想，但系统的学一下还是有好处的，硬盘里的书不看虽然不发霉，但也不能变成力量，能消磨时间，何乐不为呢。这几天打算看广告和品牌管理方面的资料，找了本《广告与品牌策划》，看着还挺来劲。

在指名式产品测验中，成功品牌的得分要远高于其竞争品牌的得分。而在盲式产品测验中，二者的得分差距不会这么大。因为盲式测验剔除了附加价值的影响，被测验者只能就产品的功能特性作出反应。但是，附加价值是附加于产品的功能特性之上的，它是无法替代的。我非常想赞同这句话，却又想告诉读者，个体的差异会导致附加价值的计算，在进行分层抽样调查统计之后，品牌价值的体现也不能完全展现，现实生活不是那么死板，在一个离婚率超过4成的社会（俺说澳洲），审美疲劳和失去新鲜感是必然的，维护品牌的同时也是对品牌概念的拓新，这也是为什么广告为什么常常是些知名品牌推出新的产品。酒香不怕巷子深到底对还是不对，已不是一句两句能够辨的明白，成功的案例和无数失败的案例（我觉得不少，只是我们根本无法差距，这就是悲哀）告诉我们，全方位的做到最好才是成功的保障。

以上产品指消耗品，不是车啊，房啊那种买不起的东西，哈哈。

遗弃在时间角落里的博文系列之-----初到澳洲杂记

前些天去了银行，把银子都交给了鬼子保管，鬼子的银行怎么看都不保险，就那么一点小小的地方，一两个服务的人，一点没有大公司的气派。暂不说外在，管理也极其混乱，柜台里居然只能存钱，取钱，很多服务都要在服务台办理，那种有点模糊的事情就不知道排哪个队，比如我想开账户，然后存钱。。。哎，想不通他们的业务能力如此低下，怎么还算发达国家？只要中国少一点官僚和腐败，绝对很快就可以超越这群只知道休息的鬼佬。
第一次存钱的时候，发现卡号居然不是银行卡上的。。。那这卡上的号又有什么作用呢？还要自己填单子，然后鬼妹就开始算你存的钱。又一次被他们折服，居然不用机器，一张一张的慢慢数，要是他们看过中国的数钱的速度，估计立马要把手给剁了不可，同样是人，差距怎么就这么大呢。我老妈估计都能管一个银行了，绝对是他们的头号招牌劳模了。他们把每一种面额的钱归类，然后每10张用一个橡皮筋绑起来，记录下各种面额各几张，然后对上我填的总数就ok了。在我的收据上盖了个章，嗯，然后我很疑惑的这么走了，心想那可是俺所有的银子啊。。但就是这样，银子就交给了他们保管，哈哈，连个真伪都不验一下，难道这群人没见过假钞吗？
走之前发现银行招实习的人，当然，最底下一般都会标明，限于澳洲公民或者是永居，嗯，不就是歧视吗？俺还歧视你们呢，要不是要用你们的银子，早换成人民币了。
看着去悉尼的往返电子机票，稍稍有点欣慰，至少天上又掉了个馅饼给我，呵呵。希望馅饼多多，俺也多多干活，积攒人品，等掉个大元宝的日子，就不这么郁闷了。
原本计划写个澳洲股市101，可以自己还没弄明白，最近时间不多，都被资本家剥削去了，不过有一点却很明显，澳洲的权证(option)市场绝对没有国内的权证市场那么容易看透，都是投机，但国内投的是机遇，难得的机会加上狂热的投机偏好，澳洲却完全是对利润最大化的理性投机。想必这幕后得到好处的,一定还是搞出这个四不像的那群管理层,蹿通了媒体的炒作和热钱的涌入,最后是价格偏离价值曲线,反而越演越烈,什么查处啊,什么严办啊,有用吗? 换个躯壳换杆枪,又是一条搅乱秩序的败类. 嗯,不久了,看看半年之后,这东西怎么收场,哈哈,我能想到的闹剧就是以一种更乱的结局来破除人们的一般性期待,从而冠冕堂皇的掩饰他们的罪行. 当然,我是这个东西受益者,因为我赚钱了.但我低估了国内这种混乱和黑暗,经过这次之后,每次投资,我都会告诉自己, "你面对的是一个混乱而黑暗的市场,不要指望靠你的理论和逻辑,贪得无厌和追求高利润是本质,学习他们操纵的手法,抓住投机的恰当机会." 宝钢才疯狂了短短两天, 不够, 只有一支玩,不够灵活,被大家盯上了还不好换地方. 大家说他要涨50%，我就涨200%,诱惑吗？我还能涨400%。只要有人跟进来一起玩，资金只要有流动，我就是活的。“不要想着最大化的利润，因为我们玩不过庄，庄家都是惹不起的主，但是跟庄赚点小钱，保赚不赔啦，哈哈”。
我绝对不相信媒体曝光的那几个小屁能够兴风作浪，我也觉得我没有见到鬼子里的精英，嗯，睡觉，精英该睡觉了，想多了就该起步来了，呵呵。

遗弃在时间角落里的博文系列之-----猴子的故事

猴子的故事其实是一个很老的故事，讲的是一棵大树，上面爬满猴子，往上看都是屁股，左右看都是耳目，往下看都是笑脸。

达尔文说，人是猴子进化来的。所以，由此衍生的故事就更加有趣了。

有人说，单位是棵树，那员工就是树上的猴子了。
有人说，社会是棵树，那我们就是吊在树上的猴子。

比喻的贴切与否，自然在学校呆着的学生是不能体会的，也便是40来岁的人酒桌上的醉话罢了。


后记
常常写些吃喝完乐的东西，大家也都看的很开心，讲起猴子的故事来，却咋无人领悟呢。这让我想起了学校的单纯，隐含马尔可夫模型中蕴含的道理可以写成论文发表，可这人际关系，复杂无比的社会关系，却何尝不值得我们细细品味呢。呜呼哀哉。

How to Convert between byte and Hex string

Please see the function below:

        /// Convert a string of hex digits (ex: E4 CA B2) to a byte array. 
        /// The string containing the hex digits (with or without spaces). 
        /// Returns an array of bytes.
        private byte[] HexStringToByteArray(string s)
        {
            s = s.Replace(" ", "");
            byte[] buffer = new byte[s.Length / 2];
            for (int i = 0; i < s.Length; i += 2)
                buffer[i / 2] = (byte)Convert.ToByte(s.Substring(i, 2), 16);
            return buffer;
        }

        ///  Converts an array of bytes into a formatted string of hex digits (ex: E4 CA B2)
        ///  The array of bytes to be translated into a string of hex digits. 
        ///  Returns a well formatted string of hex digits with spacing. 
        private string ByteArrayToHexString(byte[] data)
        {
            StringBuilder sb = new StringBuilder(data.Length * 3);
            foreach (byte b in data)
                sb.Append(Convert.ToString(b, 16).PadLeft(2, '0').PadRight(3, ' '));
            return sb.ToString().ToUpper();
        }

动态域名无法解析的解决方案

笔者通过dyndns.com注册了一个域名，并通过路由器通知域名服务商真实的IP地址。 今日我的合作伙伴需要从国内连接这个域名，却发现DNS无法解析。 这个问题在国内比较普遍，我的处理方案是通过添加一个国外的DNS服务器，从而实现解析。

以下是用来解决此问题的vbs script脚本代码，它通过快速添加DNS 150.203.x.xx，达到实现解析的目的。其实在TCP/IP属性里也可以手动添加，但过程麻烦，直接运行脚本自动添加减少了手动添加造成的不便。

On Error Resume Next
 
strComputer = "."
strNewDNSServer = "150.203.x.xx"
 
Set objWMIService = GetObject("winmgmts:" _
 & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
Set colNicConfigs = objWMIService.ExecQuery _
 ("SELECT * FROM Win32_NetworkAdapterConfiguration WHERE IPEnabled = True")

 
For Each objNicConfig In colNicConfigs
  intNewArraySize = 0
  arrDNSServerSearchOrder = objNicConfig.DNSServerSearchOrder
  If Not IsNull(arrDNSServerSearchOrder) Then
    For Each strDNSServer In arrDNSServerSearchOrder
    Next
  End If
  intNewArraySize = UBound(arrDNSServerSearchOrder) + 1
  ReDim Preserve arrDNSServerSearchOrder(intNewArraySize)
  arrDNSServerSearchOrder(intNewArraySize) = strNewDNSServer
  intSetDNS = _
   objNicConfig.SetDNSServerSearchOrder(arrDNSServerSearchOrder)
  If intSetDNS = 0 Then
  Else
  End If
Next

 
Set colNicConfigs = objWMIService.ExecQuery _
 ("SELECT * FROM Win32_NetworkAdapterConfiguration WHERE IPEnabled = True")
 
For Each objNicConfig In colNicConfigs
  If Not IsNull(objNicConfig.DNSServerSearchOrder) Then
    For Each strDNSServer In objNicConfig.DNSServerSearchOrder
    Next
  End If
Next

Things to do when you arrived and wanted to settle down in Australia

Things to do First

Below is a list of 7 important things that you should do as soon as possible after arriving in Australia.
1. Apply for a Tax File Number (TFN)

Do this first. To receive an income in Australia, you need a Tax File Number (TFN).
2. Register with Medicare

The Australian Government provides help with basic medical expenses through a scheme called Medicare.
3. Open a bank account

In Australia, most income including salary or wages and government benefits are paid directly into a bank account.
4. Register with Centrelink

Centrelink is a government agency which delivers a range of services to the community.
5. Register for English Classes

Communicating in English is very important and the key to your successful settlement.
6. Enrol Your Children in School

Under Australian law, children must attend school until they are 15 years old.
7. Apply for a Driver's Licence

Information on gaining a driver's licence.
Beginning a life in Australia Booklets

The Beginning a Life in Australia booklets welcome newly-arrived migrants and humanitarian entrants to Australia. They provide useful national, state/territory and local settlement information for migrants, humanitarian entrants, their sponsors and service providers. This information is available to download in English and 37 community languages for each state and territory.

Margin Lending Tips

1. Beat rising interest rates
Prepaying interest on a margin loan may produce interest savings in a rising interest rate environment. By locking at a competitive fixed interest rate for three, six or nine months, potential variable rate rises over the rest of the financial year can be avoided.

2. Can you claim 'professional trader' deductions?
Those who claim share trading as their profession rather than just being an investor must convince the Australian Taxation Office before they can claim trading losses as tax deductions. The ATO warns there are strict criteria to be met for someone to be classed as a share trader following confusion amongst investors who have incurred losses and then tried to offset these against their other income.


3. Caution needed on protected equity loans
Protected equity loan products allow investors to gain leveraged exposure to the sharemarket with a built-in safety net if their portfolio stocks take a dive. Investors can't lose their base capital but can keep dividends and capital gains. They also benefit from tax concessions with 100 per cent deductibility for their interest and capital protection costs. But not all financial planners and tax experts are convinced that these products are the best way to achieve a solid investment return. They say their high buy-in costs and uncertainty about when the Tax Office might change the deductibility treatment make them unattractive. Experts say the costs can run as high as 17 per cent in addition to paying loan interest when investors pay for embedded put options to protect the products' downside.

4. Don't try the prepay fiddle
If focussing on the tax benefits of prepaid interest, don't try and pull a swifty by taking out a loan, prepaying interest, then cancelling the loan and getting a refund of the interest after claiming the deduction. It won't work. Prepaid interest cannot be refunded. As a tax strategy, margin loans and prepaying interest are only beneficial if you plan on actually investing the borrowed funds.

5. Establishment fee protection
Under a protected equity loan arrangement, some lenders include the value of the establishment fee in the capital guaranteed amount. For example, if you borrow and invest $100,000 and $1000 is taken out in establishment fees, some lenders will still provide a capital guarantee over $100,000, others will only guarantee $99,000.

6. Fixed interest rates
Interest rates on protected equity products are fixed but not necessarily for the full term of the loan. Some products have a rate fixed for the full term, others reset the fixed rate each year of the loan term. These resets will reflect the interest rate environment at the time.

7. Is the interest on protected equity loans tax deductible?
There has been much debate about the deductibility of the interest payments on capital protected loans because of the difficulty in distinguishing between the capital protection component and pure loan interest component of the payments. Only the interest component is tax deductible. The amount of interest available for deduction will be the lower of:

* the amount determined by the Reserve Bank's Indicator Rate for personal unsecured loans
* the amount determined on a sliding scale depending on the term of the product (85 per cent for five years, 82.5 per cent for four years, 80 per cent for three years, 72.5 per cent for two years and 60 per cent for one year)


8. Loans for interest
Some protected equity lenders offer a separate, secondary loan to cover the first year's interest payment on a protected equity loan. These loans will have different rates, terms and conditions than the primary investment loan.

9. Prepay interest for tax benefits
Most borrowers are able to claim margin loan interest and other costs of investment as tax deductions - depending on personal circumstances. Prepaying twelve months in advance just before the end of the tax year is the way to make the most of the tax benefits. By paying a year's interest in June, the deduction can be enjoyed almost immediately in your upcoming tax return in July. But be aware that this really only amounts to tax deferment, not tax reduction. Investors are only bringing forward a tax deduction by one year, not reducing overall tax in the long run.

10. Tax advantages of borrowing to invest
There are several tax advantages when you borrow to invest in shares:

* you can claim your interest payments against your taxable income and if you earn less on the share investments than the interest payments you can claim the interest against other assessable income;
* you can prepay the interest up to 13 months ahead, prior to June 30, which is helpful for cash-flow planning and also allows you to claim the deduction a full year in advance;
* you can defer any capital gains tax liability until the shares are sold;
* as you're geared into the market you will own more shares than if you had paid cash, so you will receive more dividend payments. If the shares are franked then you can offset the franking credits against your assessable income.


11. The trade off between loan cost and share growth
Protected equity lenders broadly offer two different ways to reduce the high interest costs of their capital protected loans. 'Shared upside' simply offers the borrower a lower interest rate in return for sharing any capital growth at the end of the loan term with the borrower at a set proportion, eg. 25 or 50 per cent. Alternatively, some borrowers offer investors the ability to write call options over the stocks in their loan portfolio at preset "strike" prices. The sale proceeds from these options can be used to help fund the loan interest. But this also means that if the price of a stock in the portfolio rises above the option strike price, the buyers of the call options can then buy the stock outright from the investor, leaving the investor with only the capital growth up to the strike price.

Sending small data segments over TCP with Winsock

When a Microsoft TCP stack receives a data packet, a 200-ms delay timer goes off. When an ACK is eventually sent, the delay timer is reset and will initiate another 200-ms delay when the next data packet is received. To increase the efficiency in both Internet and the intranet applications, Microsoft TCP stack uses the following criteria to decide when to send one ACK on received data packets:

•	If the second data packet is received before the delay timer expires, the ACK is sent.
•	If there are data to be sent in the same direction as the ACK before the second data packet is received and the delay timer expires, the ACK is piggybacked with the data segment and sent immediately.
•	When the delay timer expires, the ACK is sent.

To avoid having small data packets congest the network, Microsoft TCP stack enables the Nagle algorithm by default, which coalesces a small data buffer from multiple send calls and delays sending it until an ACK for the previous data packet sent is received from the remote host. The following are two exceptions to the Nagle algorithm:

•	If the stack has coalesced a data buffer larger than the Maximum Transmission Unit (MTU), a full-sized packet is sent immediately without waiting for the ACK from the remote host. On an Ethernet network, the MTU for TCP/IP is 1460 bytes.
•	The TCP_NODELAY socket option is applied to disable the Nagle algorithm so that the small data packets are delivered to the remote host without delay.

To optimize performance at the application layer, Winsock copies data buffers from application send calls to a Winsock kernel buffer. Then, the stack uses its own heuristics (such as Nagle algorithm) to determine when to actually put the packet on the wire. You can change the amount of Winsock kernel buffer allocated to the socket using the SO_SNDBUF option (it is 8K by default). If necessary, Winsock can buffer significantly more than the SO_SNDBUF buffer size. In most cases, the send completion in the application only indicates the data buffer in an application send call is copied to the Winsock kernel buffer and does not indicate that the data has hit the network medium. The only exception is when you disable the Winsock buffering by setting SO_SNDBUF to 0.

Winsock uses the following rules to indicate a send completion to the application (depending on how the send is invoked, the completion notification could be the function returning from a blocking call, signaling an event or calling a notification function, and so forth):

•	If the socket is still within SO_SNDBUF quota, Winsock copies the data from the application send and indicates the send completion to the application.
•	If the socket is beyond SO_SNDBUF quota and there is only one previously buffered send still in the stack kernel buffer, Winsock copies the data from the application send and indicates the send completion to the application.
•	If the socket is beyond SO_SNDBUF quota and there is more than one previously buffered send in the stack kernel buffer, Winsock copies the data from the application send. Winsock does not indicate the send completion to the application until the stack completes enough sends to put the socket back within SO_SNDBUF quota or only one outstanding send condition.

How to add smecontribs repository

Log into SME Server console as root.

Issue the following command

yum update smeserver-yum

Thats all. It will add the repository on completion

Create startup script in SMEServer

SME Server is a pre-configured Linux server designed for small to medium businesses!
It used Red Hat Enterprise Linux kernel, or CentOS kernel.

When creating packages, I wanted a script to be running when the system boot up. For example, an auto usb drive mounting script. I started with something that running in the background, and didn't work quite well. Using & straight away is not a clever way because script in init.d folder should follow certain standard, and can be managed by the boot up program manager( it might be called something else).

Firstly, you can write a normal script and wrap it as the following example:

#!/bin/sh
#
# description: usbMountWrapper is the daemon to xxxxxx
#

. /etc/rc.d/init.d/functions

function start()
{
 printf "Starting %s: " "usbMountWrapper"
 daemon /opt/smebackup/usbMountWrapper &
 echo
 touch /var/lock/subsys/usbMountWrapper
}

function stop()
{
 printf "Stopping %s: " "usbMountWrapper"
 killproc usbMountWrapper
 echo
 rm -f /var/lock/subsys/usbMountWrapper
}

function reload()
{
 pid=`pidof ulogd`
 if [ "x$pid" != "x" ]; then
  kill -HUP $pid 2>/dev/null
 fi
 touch /var/lock/subsys/usbMountWrapper
}

case "$1" in
  start)
 start
 ;;
  stop)
   stop
 ;;
  restart)
 stop
 start
 ;;
  reload)
 reload
 ;;
  status)
 status usbMountWrapper
 ;;
  *)
 printf "Usage: %s {start|stop|status|restart|reload}\n" "usbMountWrapper"
 exit 1
esac

exit 0

This is a much nice way of writing boot up script and you can start or stop them like this:
/etc/rc.d/init.d/usbMountWrapper start
/etc/rc.d/init.d/usbMountWrapper stop
/etc/rc.d/init.d/usbMountWrapper restart

C# GDI double buffer to stop screen flick

The code is really simple.

this.SetStyle(ControlStyles.DoubleBuffer | ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint , true);
this.UpdateStyles();

I assume you know where to put them. Enjoy.

How to backup Linux to FAT32 External Drives

There is very good tutorial on this issue, however, i wanted to add a bit more. How to backup Linux to FAT32 External Drives | WickedBlog
The backup process sounds pretty easy, but indeed, there are heaps problems when you actually working on it.

I am a windows user, and nowadays, most product are targeting windows user.  I developed the backup utility for the SMEServer (e-smith server) and First of all,
the priority is that things can be extract in Windows.  Obviously , NTFS is not a good option cause it is not supported in SMEServer.  So Fat32 was chosen and I didn't realise the file size limit of 4G until some time had passed and all my backups are smaller than 4G.

Let's begin with backup first.

tar -czf /media/DRIVENAME/BACKUPNAME.tgz /home

This is the real simple solution to backup one folder, and of course, we have more to backup.  So, we introduce the following one:

'tar -cz --files-from '+ FILELIST_TAR + ' > ' + TAR_OUTPUT+'.tgz'

NOTE that I now read files from a list, and this is recommended to do only when programming.

Finally, we need to split it

'tar -cz - --files-from '+ FILELIST_TAR + ' |  split -b 3880m - ' + TAR_OUTPUT+'.tgz'

Re-constitute properly with this customized restore command:

cat /media/DRIVENAME/BACKUPNAME.tgz.* | tar -zxf -

And of course, I didn't forget the windows user, you can re-constitute the files like this:
copy /b BACKUPNAME.tgz.* ALL_IN_ONE.tgz /b

Enjoy

Vi: Start-up, Modes, Save and Quit

Vi: Start-up, Modes, Save and Quit

Vi: Start-up, Modes, Save and Quit

To enter Vi type:

 vi FILENAME

Vi has two modes: Normal (command) mode and edit mode.

 Switch to normal mode:     <ESC>
 Switch to edit mode:       i or a

Getting out of Vi (change to normal mode <ESC>):

 Exit Vi:                       :q
 Exit Vi (ignore changes):      :q!
 Save:                          :w
 Save and Exit:                 :wq

Switch to (edit) an other file:

:edit FILENAME

Getting help:

:help topic

.Net window form file uploader to webservice

Wanna Upload file in a asynchronise way in .Net ? Here I create a simple demo to upload your file to the webservice.
The code below is pretty useful especially creating three-tier applications and your desktop form application is not directly connecting to database.

public partial class FileUploader : Form
    {
        public FileUploader()
        {
            InitializeComponent();
        }

        private void btnBrowse_Click(object sender, EventArgs e)
        {
            using (OpenFileDialog dialog = new OpenFileDialog())
            {
                dialog.Title = "Open File";
                dialog.Filter = "All Files|*.*";
                dialog.FileName = "";

                try
                {
                    dialog.InitialDirectory = "C:\\Temp";
                }
                catch
                {
                    // skip it
                }
                dialog.ShowDialog();
                if (dialog.FileName == "")
                {
                    return;
                }
                else
                {
                    txtFileName.Text = dialog.FileName;
                }
            }
        }

        private void UploadFile(string filename)
        {

            try
            {
                // get the exact file name from the path
                String strFile = System.IO.Path.GetFileName(filename);

                // create an instance of the web service
                localhost_test.GetInfo ws = new formapp.localhost_test.GetInfo();
                ws.Credentials = System.Net.CredentialCache.DefaultCredentials;

                // get the file information form the selected file
                FileInfo fInfo = new FileInfo(filename);

                // get the length of the file to see if it is possible
                // to upload it (with the standard 4 MB limit)

                long numBytes = fInfo.Length;
                double dLen = Convert.ToDouble(fInfo.Length / 1000000);

                // Default limit of 128 MB on web server
                // have to change the web.config to if
                // you want to allow larger uploads
                if (dLen < 128)
                {

                    // set up a file stream and binary reader for the selected file
                    FileStream fStream = new FileStream(filename,FileMode.Open, FileAccess.Read);
                    BinaryReader br = new BinaryReader(fStream);

                    // convert the file to a byte array
                    byte[] data = br.ReadBytes((int)numBytes);
                    br.Close();

                    // pass the byte array (file) and file name to the web service using asynchronise way
                    ws.UploadFileCompleted += new UploadFileCompletedEventHandler(this.UploadFileCompleted);
                    ws.UploadFileAsync(data, strFile);
                    fStream.Close();
                    fStream.Dispose();

                    //// pass the byte array (file) and file name to the web service using synchronise way
                    //string sTmp = ws.UploadFile(data, strFile);
                    //fStream.Close();
                    //fStream.Dispose();
                    //// this will always say OK unless an error occurs,
                    //// if an error occurs, the service returns the error message
                    //MessageBox.Show("File Upload Status: " + sTmp, "File Upload");
                }
                else
                {
                    // Display message if the file was too large to upload
                    MessageBox.Show("The file selected exceeds the size limit for uploads.", "File Size");
                }
            }
            catch (Exception ex)
            {
                // display an error message to the user
                MessageBox.Show(ex.Message.ToString(), "Upload Error");
            }
        }

        private void btnUpload_Click(object sender, EventArgs e)
        {
            if (txtFileName.Text != string.Empty)
            {
                UploadFile(txtFileName.Text);
            }
            else
            {
                MessageBox.Show("You must select a file first.", "No File Selected");
            }
        }

        private void UploadFileCompleted(object sender, UploadFileCompletedEventArgs args)
        {
            //Bind returned results to the UI data grid
            MessageBox.Show("File Upload Status: " + args.Result + " File Uploaded.");
        }
    }

Zhen Yang's Resume

Zhen Yang

yangzhen@gmail.com Mobile 0401924381

Objective

Seeking application development position where I can utilise my skills, qualifications, research experience, and abilities in IT field that offers professional growth.

Qualifications Summary

• Technical proficiency in .Net (C#) Technology, and SQL database technologies. Over six years experiences in designing and developing web and desktop applications.
• Demonstrated capability to explore solutions and solve problems. Comprehensive industry knowledge on both Windows and Linux platform.
• Well established team work skills and management experience. Highly motivated and productive team player with client facing experience.
• Extensive knowledge on OO concepts, Design Patterns, Agile development, SDLC

Skills

l  Language: C#, ASP.Net, SQL, XML/XSLT, HTML/JQuery/CSS, WCF, UML, C++,

l  Software:   Visual Studio 2003-2010, SQLServer, IIS, TFS, WebMatrix, MySQL

l  Tools:         NHibernate, Enterprise Library, LINQ, ASP.Net MVC, Entity Framework

Technical Experiences Details

2009.07-Now   Software Developer in the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Land and Water Lab, Canberra

l  Working in a multi-disciplinary team of software developers and researchers. Working with large code base solutions in C# consisting multiple projects of libraries and components for various calibration, optimization, and simulation models, persistence of data. Familiar with the full software development life circle.

l  Daily responsibilities include developing new features for the enterprise level river modelling software according to plan. (C#, WCF, NHibernate)

l  Designed and developed standalone GUI calibration tools. (C#, SQLServer)

l  Product integration, bug fixing, performance tuning on existing code base

2007.10-2009.06 Software Developer in National ICT Australia (NICTA), Canberra

l  Constructed a customised software system for the Australian Institute of Sports as the core engineer. This multi-tier system collects data from device, analyses and stores results on central server, and allows coaches to manage and visualise athletes training sessions. It employed both Asp.Net and Windows Form technology, and used Web Service and SQLServer database as the backend.

l  Developed a GUI application to dynamically map GPS positions into formations for Defence Science Technology Organization.

l  Built various automation tools to support researcher team. Great attention to teamwork and customer service skills.

2006.01-2007.09 Part-time Programmer of Callidus Corp, Canberra, Australia

l  Created a multi-level backup utility with Web interface. (PHP, Python)

2005.01-2005.10 Technical director of FeedSky Corp, Beijing, China

l  Constructed Web2.0 site, Web Services, Web Crawler. (Asp.Net, XML/XSLT, JavaScript, SQLServer, IIS)

l  Supervised 6 software developers to deliver according to the business plan

2003.11-2004.12 Part-time Asp.Net Developer of Baihe Corp, Beijing, China

l  Developed a Quiz & Match module for the network site.(Asp.Net, SQLServer)

l  Maintained existing pages and applied bug fixes.

Education Background

2005.11-2007.09 Master by Research of Computer Science and Information Technology, Australian National University

l  Designed and constructed a Mind-Attention Software Interface, which includes data collection, processing and application plug-in modules. (C++)

l  Assisted in Virtual Reality demonstration applications development. (C#)

2001.09-2005.06 Bachelor of Computer Science, Tsinghua University, Beijing

l  No.4 in the college entrance exam to study at the best university in China.

l  Extensively studied subjects that form the basis of computer science, and actively utilised knowledge in industry during study.

Side Projects

2010            Reengineered archived projects by using ASP.NET MVC and Entity Framework

2009            Developed websites using Joomla Content Management System. (Html, CSS)

2008            Managed a team of 5 to build a Time Management system to validate my agile development knowledge. (.Net, Web Service, SQLServer)

Additional Experiences

2006-2007  Tutor in the Department of Computer Science, ANU

l  “New media and the Web” , “Automating Tools for New Media”

2007            Apple's WebObjects technology Training, Sydney

2006            Volunteer of ANU Consulting Center “Get up and Go” program

Honours and Awards

2009-2010  Member of RiverManager Software Development team which won two “Team of the Year” Awards 

2007            Publication: “Mind-modulated music in the mind attention interface”, OZCHI

2007            ANU Miscellaneous Scholarship and Vice-Chancellor Travel Grants