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对梵高作品的物理分析 sinophysiker 告诉我们 arxiv 上有这样一篇文章：Turbulent luminance in impassioned van Gogh paintings。：）摘要：
Everything in the last period of Vincent van Gog...
Oracle 初始化参数 DB_FILE_MULTIBLOCK_READ_COUNT (MBRC) 默认值一般是比较低的，在进行一些比较大的数据操作的时候，恰当的调整当前 Session 的 MBRC 的值可能会在 IO 上节省一点时间。
DB_FILE_MULTIBLOCK_READ 这个参数的值并不是可以无限大, 大多数平台下的 Oracle 都是 128。一般 Oracle 的 Block Size 是 8K 。128*8K=1M 。 这个 1M 是大多数操作系统一次最大 I/O 的限制。前面的限制要从这个 1M 推回去，初始化参数 DB_FILE_MULTIBLOCK_READ_COUNT 的最大值之所以定为 128 ，也是一个比较保守的策略。
Oracle 的 Metalink Note:291239.1 有一小段说明：
Each version of Oracle on each port, is shipped with a preset maximum of how much data can be transferred in a single read (which of course is equivalent to the db_file_multiblock_read_count
since the block size is fixed). For 8i and above (on most platforms) this is 1Mb and is referred to as SSTIOMAX.
To determine it for your port and Oracle version, simply set db_file_multiblock_read_count to a nonsensical value and Oracle will size it down for you.
SSTIOMAX 中的 SST 代表什么意思不为人知：
SSTIOMAX is an internal parameter/constant used by oracle, which limits the maximum amount of data transfer in a single IO of a read or write operation. This parameter is fixed and cannot be tuned/changed
要查看当前系统上的 SSTIOMAX 限制，可以通过如下做法简单的得到(trace 10046 的方法似乎麻烦了一些):
foo@DEMO> show parameters db_file_multiblock_read_count
NAME TYPE VALUE ------------------------------------ ----------- ------- db_file_multiblock_read_count integer 16
foo@DEMO> ALTER SESSION SET db_file_multiblock_read_count =256;
Session altered.
foo@DEMO> SELECT VALUE FROM v$parameter WHERE NAME = 'db_file_multiblock_read_count';
VALUE -------------------- 128
正常运行的库，MBRC 并非越大越好(除了 IO 效率有降低的可能，也会有可能影响 CBO 的运行)。后者是我的猜测，因为在 10gR2 上，'db_file_multiblock_read_count' 参数引入了两个相关的隐含参数(Refer):
_db_file_exec_read_count _db_file_optimizer_read_count
距离上一次写技术备忘似乎有好久了...这几天比较累
--EOF--
年会的“创业与投资”板块的特约嘉宾Jason Yin 专业从事Web 2.0 研究，他最近整理了年会期间的思路，撰小文说明自己对Web 2.0创业的一些感想：
演讲人如 果让你从投资者和创业者两者之间选出一个弱势群体的话，你会挑选谁？估计十有八九的人会选择创业者。但是我不这么看。在最近几次的会议中，我接触到的风险 投资者，都告诉我他们最大的挑战是：找不到真正好的项目。那么什么是真正好的项目呢？我写了一首七言绝句，就算是给创业者指点一下迷津，帮助创业者想VC 之所想，急VC之所急。
这首七言绝句是这么说的：产品客户能收钱，简单扩展有壁垒，趋势独特可持续，团队人脉养 小孩。这分别是从四个方面说的，包括了从入门到精通，从外部到内部。产品、客户、能收钱，是任何生意的基础，就是开一个饭馆也得具备这样的条件。产品就是 你的主打价值提供是什么，很多创业者侃侃而谈很有吸引力，但是让人不知道能从他那里买什么，眼球注意力转化不了价值。这其实也是生意中最难的，中国的企业 都是草根性发展起来的，头一两年往往是在跌跌撞撞找产品定位和公司定位的过程中。—–[给创投上课：运营虚拟草根社区]
演讲人
，把两则新闻合并成一则了？
an interesting online service that allows users to explore & share insights with others, based on stored datasets about politics, economics, weather, sports, business & more. more specifically, the website allows people to explore popular or obscure datasets, search for patterns while surfing the colorful graphs, datasets & opinions, & share these insights by posting graphs to blogs or websites.
will this be the YouTube for data visualization?
[link: swivel.com]
Several new enhancements of note from the Search team: Tomorrow we’re releasing the beta version of Live Search Books (http://books.live.com). Check out the user experience: very clean! With this initial release we’ve focused on making the reading experience as natural as possible.
The U.S. beta launch of Live Search Books is a big step forward in advancing the way people discover information through the integration of content that has been “off-limits” to the traditional Search experience, until now. This release makes tens of thousands of out-of-copyright books available from our library scanning initiative, including books from the University of California, the University of Toronto, and the British Library. In addition, we are announcing new partnerships with the New York Public Library and the American Museum of Veterinary Medicine. The Live Search team is working hard to offer the most relevant Search service to you, our customers. There is a lot of trusted and authoritative content that can only be found in books today. With this beta launch we’ve taken our first steps toward making that content discoverable and easy to read.
The team is also taking this opportunity to announce an update to the beta of Live Search Academic (http://academic.live.com). We’re adding millions of new articles—primarily bio-medical content. Live Search Academic now indexes thousands of academic journals in the computer science, engineering, physics, and bio-medical fields. We’re also now indexing theses, dissertations, and books within these disciplines.
These are just a few of the most recent examples of our efforts to deliver the most relevant content available; whether it is in a book, in an academic journal or on the web. A feedback link will be available shortly; in the meantime, please give us feedback via this blog.
--- Cliff Guren, Director of Publisher Evangelism
作者：呆马 一个普通用户
按照常规，这篇文章的“标准署名”应该是 “刘林岚 图片搜索产品经理”。不过呢，这次我想从一个普通用户的角度跟您聊聊我自己使用图片搜索中的一个小故事。所以就采用了这样一个署名。
老婆说我优点不多，在为数不多的优点之中，“会找头像”是其中之一。老婆朋友多，爱网聊，还经常根据最近的心情和喜好更换聊天头像。每到这时候，我的作用就发挥出来了。比如老婆有些天狂爱机器猫，让我帮她找机器猫的聊天头像，我就能通过图片搜索找到一堆能做头像的图来让她挑选。
说来容易，这事情做起来可远没么简单。现在的图片搜索，大都按照相关性排序，可是头像是要考虑大小的，所以我经常不得不翻N多页，发现一个就保存一个……老婆又三天两头就要换头像，所以这个工作可算是耗时耗力，还经常因为数量不够遭到老婆痛扁。
但是在新版的雅虎图片搜索中，这一切变得简单起来。
和别的图片搜索引擎不一样的是，新雅虎图片搜索框可以专门搜索“聊天头像”！
啥都甭说了，先搜个老婆最爱的“机器猫”试试。效果还不错啊，搜出来的还都是正好QQ里面能用的40*40的头像！
点开之后就可以直接看到原网站的这张图片
比原来那种我用老套的方法效率高多了！再试试老婆中意的“蜡笔小新”，爽呆！
继续试“EVA”、“火影忍者”的头像，不要太多哦！看着满屏的聊天头像，我流着口水开始YY老婆高兴的表情……再试试其他的一些词，大部分结果都令人满意，足够那些想经常换头像和像我一样为老婆效劳的人用啦:D
更多的能搜出好头像的搜索词我已经想不出来了，好在新的雅虎图片搜索提供了分类列表导航，可以迅速找到你感兴趣分类下的关键词：
雅虎图片搜索引擎给用户的另外一个惊喜是可以搜索聊天表情。像前一阵我和老婆经常用的“悠嘻猴”、“WS熊”，搜到的结果都很不错。
比较体贴的是搜索结果页的变化——在各个分类加入了切换标签，如果你也是个机器猫迷，你可以只用“机器猫”一个搜索词就可以把机器猫的壁纸、头像、表情一网打尽了！
做好男人不容易，但要是找对了方法起码会相对轻松一点哈！雅虎图片搜索，让男人好起来，让好男人更好（这句话貌似有点…:)）
作为产品经理我还得跳出来再啰嗦几句
1、目前“聊天头像”搜索的是QQ头像，搜索“雅虎通/MSN头像”的功能很快就会上线。
2、我们会逐步推出更多的图片搜索中的细分搜索，让想找图片的用户能更快更好的找到需要的图片。
3、我们会不断对“壁纸”、“聊天头像”和“聊天表情”做更加精细的调整，搜到的结果会越来越好！
4、感谢我们的用户，是你们热情细致的反馈，让我们能够持续改进产品!
It may be about time to put an end to the debate about whether feeds are going mainstream. Adding to our list of 19th century publishers (they're not our first, or even our third: we checked), The Wall Street Journal Online, the largest paid subscription site on the Web, MarketWatch.com, a leading investing and financial news site, and Barron’s Online, America's premier financial weekly, are now offering enhanced FeedBurner feeds for their sites, blogs and podcasts. Dow Jones has also selected the FeedBurner Ad Network as its choice for monetizing these feeds.
The Dow Jones properties are relying on FeedBurner to integrate with the Web's most popular social media services like digg and del.icio.us using our innovative FeedFlare service. As John Gartner points out on the MarketingShift.com site today, "FeedFlare can include links for many of the Web 2.0 services that can give a tremendous boost to an article's visibility." (That's right: feeds can drive traffic and revenue. Dow Jones just might be on to something here.)
The Wall Street Journal Online currently offers 206 text and podcast feeds, Barron’s Online offers 45 feeds, and MarketWatch.com’s more than 212 text and podcast feeds will be available later this month. Content feeds such as Walt Mossberg’s Personal Technology column and MarketWatch’s Morning Stock Talk podcast feature one-click subscription to popular feed-reading clients like Google Reader or iTunes. WSJ.com even has a feed about holiday sales trends to get you in the spirit.
Is your publication stuck in the 19th century, looking for a 21st century way to drive traffic to your site, generate revenue from your content, and add value for your audience? Contact us. The future awaits.
(Fame and fortune await anyone who wants to guess in the comments who the other 19th century early adopters are. Disclaimer: our lawyers require us to point out that by "fortune", we mean "fame". As in "Internet famous." ...At FeedBurner's headquarters, anyway. No wagering.)