## 一人の日本に行く（3）：神奈川東岸で急行（後編） [My Trip to Japan: Cruising the Cities along the Tokyo Bayshore (Part 2)]

（平成２３年２月３日・木曜日）

みなとみらい線列车的内部

みなとみらい２１

New York Times上的一则专栏曾经说过，”Modern Japan simply was cyberpunk“。这里的现代化程度、卫生和秩序，甚至会让老牌欧美中心London和Manhattan汗颜。记得当初在JFK降落时，望着下面的稀疏的黯淡的黄色灯光，与Friends中那个泛着金黄色灯光的摩天楼岛真是天壤地别；心中不得露出一丝失望。而香港、東京的灯光则是连成一片的蓝白色，充满了能量。世界的未来在亚洲。这里是日本乃至亚洲未来大都会的范本。

## Boosting != Boosting Cascade

In machine learning literature, boosting and support vector machine (SVM) are the most popular algorithms out of box.

The emergence of boosting, which originated from almost an engineering-based perspective (multiple weak classifiers combine together to yield a strong one), is earlier, and less mathematically deliberate than SVM.

Upon the introduction of rapid face detection by Viola and Jones, the use of boosting, at least in the CV context, almost bears the same meaning as fast and simple. This is, however, not quite the exactly true.

First of all, the 2001 paper by Viola and Jones uses Haar feature, a feature that can be computed very fast from integral image, which is also easily obtained from a gray image.

Secondly, they employ a modified boosting algorithm that uses 1 stage at a time. As a reminder, suppose that the boosting score is expressed as a weighted voting of individual classifiers

$h_m(\mathbf x) = \alpha_1 h_1(\mathbf x) + \alpha_2 h_2(\mathbf x) + \cdots + \alpha_m h_m(\mathbf x)$

This expression is by no means simpler than the SVM computation. It does not even differ from any monolithic classifier.

The two reasons above bankrupt the idea that boosting == fast.

The boosting cascade introduced by VJ is trained in a way such that the classification is divided into multiple stages. Each time only one test $h_i(\mathbf x)$ is considered. If the test passes, go to the next test; otherwise reject. Only the candidate that passes all $m$ rounds is regarded as positive. This is effectively a degenerated decision tree, which boosts the classification speed by rejecting many candidates that fail at early stages.

Therefore, boosting cascade == fast.

## 外交部香港公署换领护照指南（同时适用于补办，注销）

（thx 小伟）所需材料：

1. 原护照（如有）

2. 通行证（如有）

3. 复印 （如有…)

1）原护照资料页（带名字照片那页）

2）原护照备注页（如果备注页有换发或者延期信息）

3）通行证资料页

4) 护照或者通行证上的有效香港签注页和内地签注页

5) 香港和国内身份证

4. 照片三张 （要求不严格，大小和通行证照片一样，白底或者浅蓝底）

5. 填表（当场领取）

6楼相当冷清。有取号机不过不需要领号，服务台大多时间是闲着的。需要提醒的是办证时看好自己的书包。大厅里的邦人素质很是问题。

（平成２３年２月３日・木曜日）

Perry上陸地

Perry纪念碑

Perry纪念馆前的半身像