随着 blog entry 数量的增加,迁移也越发费时费力了……
不过 MT 的表现从目前来看很值得。
目前暂时开放匿名 comment,如果垃圾评论太多的话就要考虑只允许登录的人评论了。
搜索此博客
2007年10月19日星期五
2007年10月18日星期四
What you know, you don't know, and you thought you know about resilience
Today I stumped on [this article](http://www.ecologyandsociety.org/vol11/iss1/art13/main.html) on [Google Scholar](http://www.google.com/). I think it is a good one for people just beginning to study resilience (with all due respect; those people include me).
I haven't got time to read it slowly but from my skimming I think it is good in terms of clarifying some concepts and methodology issues. Return to it from time to time we may save ourselves considerable energy and do more sound research.
The article has no access restriction as long as you have Internet connection.
I haven't got time to read it slowly but from my skimming I think it is good in terms of clarifying some concepts and methodology issues. Return to it from time to time we may save ourselves considerable energy and do more sound research.
The article has no access restriction as long as you have Internet connection.
2007年10月17日星期三
Computation, modelling and resilience
I just attended a (poorly organised) seminar on my university's computer cluster system. Presumably it can facilitate computation in my study, if any. It is easy to think about using it in some resilience models, I can add a lot of factors and agents in the model so the result would be ... so what?
Given enough time and opportunities to collect data I will be able to produce a reasonably good model for the dynamics of grasslands in Tibet. But to convince myself that this model can be actually used to describe the resilience difference between different management styles, I need to validate it. But how?
Usually we would put data from 200 years ago into the model, let the model simulate what happened in 100 years after that, then compare the output with what was actually there 100 years ago. If the comparison shows enough similarity between simulation and reality, suppose the key things determining the system's behaviour haven't changed, we can use the model to predict next 100 years from now on. But this is not always the case for resilience modelling. Itself tries to predict what would happen if key variables and system behaviour changes.
Therefore I think modelling should not be the end but a means in resilience study. Modelling helps us find key agents, variables, and behaviours in the system. God-willing, it would be easier to define domains of attraction and therefore resilience in the system.
For now, it seems plausible trying to build a model based on the findings up-to-date and see how management styles and environmental changes affect the system, thus identify the key variable.
I am considering using spatial or agent-based model to tackle this problem.
Given enough time and opportunities to collect data I will be able to produce a reasonably good model for the dynamics of grasslands in Tibet. But to convince myself that this model can be actually used to describe the resilience difference between different management styles, I need to validate it. But how?
Usually we would put data from 200 years ago into the model, let the model simulate what happened in 100 years after that, then compare the output with what was actually there 100 years ago. If the comparison shows enough similarity between simulation and reality, suppose the key things determining the system's behaviour haven't changed, we can use the model to predict next 100 years from now on. But this is not always the case for resilience modelling. Itself tries to predict what would happen if key variables and system behaviour changes.
Therefore I think modelling should not be the end but a means in resilience study. Modelling helps us find key agents, variables, and behaviours in the system. God-willing, it would be easier to define domains of attraction and therefore resilience in the system.
For now, it seems plausible trying to build a model based on the findings up-to-date and see how management styles and environmental changes affect the system, thus identify the key variable.
I am considering using spatial or agent-based model to tackle this problem.
2007年10月16日星期二
Firefox 的杀手级扩展── Zotero
嗯,我也标题党一回。Zotero 对我来说确实是杀手级的一个应用,不过对于没有这方面需求的人来说它也就是一个普通的扩展。那么具体是什么样的需求呢?大量文献信息的组织,文献的有序保存,以及按需调用。
不错,这正是许多文献管理软件,比如[Endnote](http://www.endnote.com),[RefWorks](http://www.refworks.com),以及 [jabref](http://jabref.sourceforge.net) 都具有的功能。但是回忆一下我们在使用这些软件时的行为:看到一篇文献,点击输出参考文献的链接,选择格式,然后等待软件启动,导入文件后我们再把焦点重新放回到浏览器继续浏览。在看文献的过程中我们还要找个东西记笔记,笔记如果不能很好地组织起来,又怕将来忘记,所以每篇笔记还得加上有关文献的链接。这样是无法建立一个有效率的个人[工作流](http://www.answers.com/topic/workflow)的。
Zotero 就不同,它把我们进行文献研究时的主要活动──搜集,整理,阅读和引用都很好地集成到了一个界面之内,就在浏览器的一角,唾手可得,而且没有 Endnote 那种复杂的下拉式菜单,一切都可以用快捷按钮和上下文菜单解决([这里](http://www.zotero.org/images/quick_start/zoteropane_800x635.png)是界面的截图,版权归原所有人)。在 [Google Scholar](http://scholar.google.com) 和 [Web of Knowledge](http://www.isiknowledge.com) 之类搜索引擎和 Elsevier、Springer 等出版商的网站上还可以利用自动发现功能一键添加文献数据。
大多数情况下,使用 Zotero 的流程可以归纳为:在互联网上发现文献──(利用 [SFX](http://www.exlibrisgroup.com/sfx.htm) 等文献服务发现全文)──利用导入功能得到文件信息和有关附件(pdf 等)──做笔记、tag、与相关文件链接──搜索文献──输出有关文献为其他软件格式──在 TeX 或字处理软件中引用。除最后一步外都不需要打开任何其他软件。
此外,Zotero 的相关文献功能允许我们把关键词和标题上看不出任何联系的文章放在一起,这在我们进行某些跨学科研究时非常方便──比如讨论航海技术和全球化的联系。Zotero 的其他特色功能还包括对 pdf 文件进行索引,通过搜索创建类似于 MacOS X 的智能文件夹,对多种文献来源和格式的支持,在文献快照上进行批注(仅限于文本和 html 文件),以及文献时间线的创建(对于写 review 非常有用)。在 [Zotero 官方网站](http://www.zotero.org)上有对这些功能的[详细介绍和教程](http://www.zotero.org/documentation/)。
据说将来 Zotero 也会引入类似 RefWorks 的线上文献库功能,但是现在使用本地 sqlite 数据库的好处是可以方便地脱机使用,也可以用备份和版本控制工具管理。我倒是希望 Zotero 将来能有这些功能:
- 单独搜索笔记和批注
- 界面上对搜索词高亮
- 记录文献库中项目的访问时间,并可用它作为条件搜索最近看过的文献
- 增加对更多文献数据库的自动发现功能,或者允许用户自己添加自动发现网站和信息提取语法(更新:Zotero 的[开发网站](http://dev.zotero.org/scaffold/)上提供了扩展的下载,用于“高级”用户自行添加 site translator)
总地说来 Zotero 是我目前遇到的用得最顺手舒心的文献管理和笔记软件,向任何看到这篇 blog,平时上网不仅仅是看 YouTube 的人推荐。
\[再更新:如果你是大学内的用户,可以把默认的 OpenURL 解析器(Resolver)改成自己的 sfx 或者其他类似服务的解析器。各学校的解析器 url 可能不太一样,但你自己用 sfx 搜索一次以后就应该知道是怎么构成的了,在设置中填上,用 Locate/定位功能实验一下即可。\]
不错,这正是许多文献管理软件,比如[Endnote](http://www.endnote.com),[RefWorks](http://www.refworks.com),以及 [jabref](http://jabref.sourceforge.net) 都具有的功能。但是回忆一下我们在使用这些软件时的行为:看到一篇文献,点击输出参考文献的链接,选择格式,然后等待软件启动,导入文件后我们再把焦点重新放回到浏览器继续浏览。在看文献的过程中我们还要找个东西记笔记,笔记如果不能很好地组织起来,又怕将来忘记,所以每篇笔记还得加上有关文献的链接。这样是无法建立一个有效率的个人[工作流](http://www.answers.com/topic/workflow)的。
Zotero 就不同,它把我们进行文献研究时的主要活动──搜集,整理,阅读和引用都很好地集成到了一个界面之内,就在浏览器的一角,唾手可得,而且没有 Endnote 那种复杂的下拉式菜单,一切都可以用快捷按钮和上下文菜单解决([这里](http://www.zotero.org/images/quick_start/zoteropane_800x635.png)是界面的截图,版权归原所有人)。在 [Google Scholar](http://scholar.google.com) 和 [Web of Knowledge](http://www.isiknowledge.com) 之类搜索引擎和 Elsevier、Springer 等出版商的网站上还可以利用自动发现功能一键添加文献数据。
大多数情况下,使用 Zotero 的流程可以归纳为:在互联网上发现文献──(利用 [SFX](http://www.exlibrisgroup.com/sfx.htm) 等文献服务发现全文)──利用导入功能得到文件信息和有关附件(pdf 等)──做笔记、tag、与相关文件链接──搜索文献──输出有关文献为其他软件格式──在 TeX 或字处理软件中引用。除最后一步外都不需要打开任何其他软件。
此外,Zotero 的相关文献功能允许我们把关键词和标题上看不出任何联系的文章放在一起,这在我们进行某些跨学科研究时非常方便──比如讨论航海技术和全球化的联系。Zotero 的其他特色功能还包括对 pdf 文件进行索引,通过搜索创建类似于 MacOS X 的智能文件夹,对多种文献来源和格式的支持,在文献快照上进行批注(仅限于文本和 html 文件),以及文献时间线的创建(对于写 review 非常有用)。在 [Zotero 官方网站](http://www.zotero.org)上有对这些功能的[详细介绍和教程](http://www.zotero.org/documentation/)。
据说将来 Zotero 也会引入类似 RefWorks 的线上文献库功能,但是现在使用本地 sqlite 数据库的好处是可以方便地脱机使用,也可以用备份和版本控制工具管理。我倒是希望 Zotero 将来能有这些功能:
- 单独搜索笔记和批注
- 界面上对搜索词高亮
- 记录文献库中项目的访问时间,并可用它作为条件搜索最近看过的文献
- 增加对更多文献数据库的自动发现功能,或者允许用户自己添加自动发现网站和信息提取语法(更新:Zotero 的[开发网站](http://dev.zotero.org/scaffold/)上提供了扩展的下载,用于“高级”用户自行添加 site translator)
总地说来 Zotero 是我目前遇到的用得最顺手舒心的文献管理和笔记软件,向任何看到这篇 blog,平时上网不仅仅是看 YouTube 的人推荐。
\[再更新:如果你是大学内的用户,可以把默认的 OpenURL 解析器(Resolver)改成自己的 sfx 或者其他类似服务的解析器。各学校的解析器 url 可能不太一样,但你自己用 sfx 搜索一次以后就应该知道是怎么构成的了,在设置中填上,用 Locate/定位功能实验一下即可。\]
Labels:
Happy Hacking
2007年10月10日星期三
Defining and studying complexity in ecosystems
There are some new projects relating to complexity studies in some UK Universities (e.g. [University of Bristol](http://bccs.bris.ac.uk/), [University of Warwick](http://www2.warwick.ac.uk/fac/cross_fac/comcom/)). Although I doubt how many enrolled in these programs would know what are complexities in complex systems (in contrast to "simple" systems such as computers). At least I don't understand.
One interesting definition of complexity is the length of the shortest description of a series of the system's regularities. This definition can only be used in comparisons because it is not possible to cover all classes of regularities in a system. For ecosystems there may be a defined set of regularities that can be used to describe the complexity of the system.
For the moment we cannot tell how complexity of a system is linked to its unpredictability and surprises. We only know that a complex system may have these features: emergence, surprises, chaos, and paradoxum. Some tools are being developed to get a grasp of complex systems, but the success is still limited. These tools may be only suitable for a limited range of applications.
Can we at last deal with complexity in a scientific way? Possibly we can deal with it with more certainty as science develops. But a more likely scenario is that we incorporate uncertainty and complexity into the existing science system, just like what quantum mechanics did. Ecology and sociology recognising complexity may have a complete shift in the coming decades.
One interesting definition of complexity is the length of the shortest description of a series of the system's regularities. This definition can only be used in comparisons because it is not possible to cover all classes of regularities in a system. For ecosystems there may be a defined set of regularities that can be used to describe the complexity of the system.
For the moment we cannot tell how complexity of a system is linked to its unpredictability and surprises. We only know that a complex system may have these features: emergence, surprises, chaos, and paradoxum. Some tools are being developed to get a grasp of complex systems, but the success is still limited. These tools may be only suitable for a limited range of applications.
Can we at last deal with complexity in a scientific way? Possibly we can deal with it with more certainty as science develops. But a more likely scenario is that we incorporate uncertainty and complexity into the existing science system, just like what quantum mechanics did. Ecology and sociology recognising complexity may have a complete shift in the coming decades.
Labels:
Academic Thought
2007年10月3日星期三
Annual presentation
I received the notice that I am going to do the presentation today when I was in China, busy packing my luggage to go back to England. So it was quite a fuss. Luckily I was preparing a presentation knowing that I will need it some time.
The most difficult thing is to introduce the concept of resilience to an audience of human geography background. Sometimes I wonder why I do such a ``biological'' project at school of Geography. However, things turned not so bad. Resilience has become a more widely accepted metaphor and method nowadays.
The slide I made lack a bit of consistency I am afraid. It may left the audience trying to grab the topic. It would be better if there are some links between the different parts.
Next week there will be another group of PhD students doing presentation, I think I'd better learn from them about how to make more understandable presentations....
The most difficult thing is to introduce the concept of resilience to an audience of human geography background. Sometimes I wonder why I do such a ``biological'' project at school of Geography. However, things turned not so bad. Resilience has become a more widely accepted metaphor and method nowadays.
The slide I made lack a bit of consistency I am afraid. It may left the audience trying to grab the topic. It would be better if there are some links between the different parts.
Next week there will be another group of PhD students doing presentation, I think I'd better learn from them about how to make more understandable presentations....
2007年10月1日星期一
Bourne 走出谍影
原以为我9月底回到小岛后,没有机会再看已经上映一个多月的 Bourne Ultimatum,得等 DVD 了。没想到影院里还有场次,更没想到入场之前还需要排队。
Bourne 系列拍到现在,再翻译成《谍影重重》似乎已经不太恰当了。在第一集里观众可能和 Bourne 一样一头雾水,需要不断寻找真相,而第三集里对于观众来说一切他们关心的真相似乎都已大白,剩下的只是看 Bourne 如何找回自我。在这种条件下,如何保持影片的悬疑色彩就成为对导演的一大挑战。让观众增强对 Bourne 的代入感是最容易想到的一种办法,但是一旦观众不能入戏,就容易觉得不知所云。Paul Greengrass 作为一个以纪录片风格著称的导演,自然也更习惯于用第三人称的视角来拍戏。这一集里他很聪明地没有强求观众体会 Bourne 所感受到的重重迷雾,而更多地把注意力集中在双方的斗智戏上,于是保留了 Bourne 系列中那种旧式间谍影片的剧情张力。
但是这部戏毕竟不是 The Good Shepherd 这样的纯剧情片。大概是为了和暑期档其他的动作影片抗衡,影片的动作场面比上一集增加了不少,而且打戏兼顾了 Identity 中令人眼花缭乱的动作设计和 Supremacy 中拳拳到肉的拍摄风格,可谓三部中最佳的一作。不过追车戏感觉不如 Supremacy 中精彩,主要可能是因为时间太短,而且混乱的街道让 Paul 的拍摄更显混乱。但总的来说,动作戏比上一集精彩许多。
表演方面,女演员比男演员出彩,Julia Stiles 和 Joan Allen 分别饰演 Nicki 和 Pamela,表现不错。Matt Damon 又要演动作戏,又要诠释失忆杀手,基本都比较到位,也够难为他了,不过总觉得他在后半段的表演还是力有不逮。如果有第四部的话,可以想见表演的参照物会越来越少,要演好越来越难,Matt 及早宣布收手应该是个正确的抉择。
当大家都在拿 Bourne 跟 Bond 做比较时,可以说前者也已经成为了一个文化符号,片尾字幕最后的画面更增强了这种感觉。Ultimatum 可以说是这个系列的一个巅峰,但是原作者 Robert Ludlum 提供的这个失忆杀手的概念在这一作也应该是走到了一个尽头,再拍第四第五集的话就只能是榨取剩余价值了。或许 Jason Bourne 会成为像 James Bond 那样长盛不衰的银幕形象,但到目前为止的这个 Bourne 才是最独一无二,最值得记住的。
p.s. 从影片前的片花得知 Hitman: Codename 47 系列也被改编成电影了,既然女主角不好看,我的希望就是它能拍出游戏的深度,不要又是一个狂洒狗血和子弹的感官刺激片。
Bourne 系列拍到现在,再翻译成《谍影重重》似乎已经不太恰当了。在第一集里观众可能和 Bourne 一样一头雾水,需要不断寻找真相,而第三集里对于观众来说一切他们关心的真相似乎都已大白,剩下的只是看 Bourne 如何找回自我。在这种条件下,如何保持影片的悬疑色彩就成为对导演的一大挑战。让观众增强对 Bourne 的代入感是最容易想到的一种办法,但是一旦观众不能入戏,就容易觉得不知所云。Paul Greengrass 作为一个以纪录片风格著称的导演,自然也更习惯于用第三人称的视角来拍戏。这一集里他很聪明地没有强求观众体会 Bourne 所感受到的重重迷雾,而更多地把注意力集中在双方的斗智戏上,于是保留了 Bourne 系列中那种旧式间谍影片的剧情张力。
但是这部戏毕竟不是 The Good Shepherd 这样的纯剧情片。大概是为了和暑期档其他的动作影片抗衡,影片的动作场面比上一集增加了不少,而且打戏兼顾了 Identity 中令人眼花缭乱的动作设计和 Supremacy 中拳拳到肉的拍摄风格,可谓三部中最佳的一作。不过追车戏感觉不如 Supremacy 中精彩,主要可能是因为时间太短,而且混乱的街道让 Paul 的拍摄更显混乱。但总的来说,动作戏比上一集精彩许多。
表演方面,女演员比男演员出彩,Julia Stiles 和 Joan Allen 分别饰演 Nicki 和 Pamela,表现不错。Matt Damon 又要演动作戏,又要诠释失忆杀手,基本都比较到位,也够难为他了,不过总觉得他在后半段的表演还是力有不逮。如果有第四部的话,可以想见表演的参照物会越来越少,要演好越来越难,Matt 及早宣布收手应该是个正确的抉择。
当大家都在拿 Bourne 跟 Bond 做比较时,可以说前者也已经成为了一个文化符号,片尾字幕最后的画面更增强了这种感觉。Ultimatum 可以说是这个系列的一个巅峰,但是原作者 Robert Ludlum 提供的这个失忆杀手的概念在这一作也应该是走到了一个尽头,再拍第四第五集的话就只能是榨取剩余价值了。或许 Jason Bourne 会成为像 James Bond 那样长盛不衰的银幕形象,但到目前为止的这个 Bourne 才是最独一无二,最值得记住的。
p.s. 从影片前的片花得知 Hitman: Codename 47 系列也被改编成电影了,既然女主角不好看,我的希望就是它能拍出游戏的深度,不要又是一个狂洒狗血和子弹的感官刺激片。
订阅:
博文 (Atom)