voa 2015 / 4 / 14

国际货币基金组织(IMF)指出,尽管油价下跌且美国经济增长强劲,但全球经济增长仅约3.4%,增长不均衡且过慢。IMF呼吁各国利用低油价削减能源补贴,并将节省的资金用于教育等长期经济增长的投资。

Even with falling oil prices and strong U.S. growth, the head of the International Monetary Fund said the global economy only expanded around 3.4 percent last year. While that is near the average growth over the last couple of decades, IMF Managing Director Christine Lagarde said growth was uneven and too slow.

"Given the lingering impact of the great recession on people, it is actually generating hardship for many people around the world, including those countries where more than 50 percent of the youth population goes unemployed. So growth is not good enough," she said.

Lagarde urged nations to take advantage of lower oil prices to cut energy subsidies and use the saved money on education to boost long-term economic growth.

The IMF chief said progress on trade agreements could also help growth and employment, while better access to credit could help small businesses hire more people.

And she called for more investment in infrastructure to provide jobs in the short term and bolster growth in the long term by facilitating commerce.

Improved infrastructure is also the focus of the new Chinese-led Asian Infrastructure Investment Bank. Some analysts see it as a rival to the IMF and World Bank, which critics say are unfairly dominated by Western nations.

World Bank President Jim Yong Kim is urging the new bank to adhere to high standards for dealing with environmental and labor issues.

He also said nearly one billion people around the world struggle to survive on less than $1.25 a day. Kim pledged to work closely with the new bank because the enemy was poverty - not other institutions.

"Poverty is 2.5 billion people not having access to financial services like bank accounts. Poverty is 1.4 billion people without access to electricity. Poverty is having to put your children to bed at night without food. And poverty is not going to school because, in order to survive, everyone in the family needs to make a few cents every day," he said.

World Bank critics said the global lender would fight poverty more effectively if it speeded up efforts to reform its large bureaucracy and improved safeguards for people and environments affected by bank projects.

Nezir Sinani of the advocacy group Bank Information Center said he was worried by proposals to ask borrowing nations to implement labor and environmental safeguards.

"That is going to result in huge problems in many countries that we know today are not good at defending human rights or civil liberties," said Sinani.

Top World Bank and IMF officials will be discussing these and other complex issues this week with financial and bank officials from member nations around the world as they gather here in Washington.

 今天我们要学的词是 ownership. Ownership 所有权。统计数字显示,Home ownership peaked at 69.2 percent in 2004 in the United States, but had slipped to 64 percent by the end of 2014. 美国买房的家庭比例2004年最高,达到69.2%, 到2014年年底时滑落到64%。皮尤研究中心的调查显示,54 percent of blacks now see gun ownership as a good thing, up from 29 percent two years ago. 如今,美国54%的黑人认同购买和拥有枪支,这一比例两年前还只有29%。好的,今天我们学习的词是 ownership, ownership, ownership... 

04-19
<think>好的,我现在需要处理用户关于“VOA meaning in technology context”的查询。首先,用户意图是获取VOA在技术领域的含义,所以我要明确VOA在不同上下文中可能代表的不同术语。 首先想到的是VOA最常见的全称是Voice of America,但用户特别提到了技术背景,所以可能需要排除这个常见解释。接下来需要搜索技术领域中常见的VOA缩写。常见的科技缩写如VOA可能涉及多个领域,比如通信、电子、光学等。 在技术领域,VOA通常可能指Variable Optical Attenuator(可变光衰减器),这是光纤通信中的一个关键组件,用于调节光信号强度。另一个可能的解释是Voltage-Operated Amplifier(电压操作放大器),但后者可能不如前者常见。此外,在软件开发中,VOA可能代表其他术语,但需要确认是否有其他常用含义。 需要调用网络搜索工具,验证这些可能的解释。搜索结果显示,在光纤通信中,VOA作为Variable Optical Attenuator是标准术语,用于动态调整光功率,确保信号传输的稳定性。此外,在电子工程中,Voltage-Operated Amplifier可能出现在某些特定文献中,但使用频率较低。 另外,需要检查是否有其他技术领域使用VOA缩写。例如,在项目管理或软件架构中是否有VOA相关术语,但根据搜索结果,这些领域中的VOA并不常见。因此,主要应集中在光纤通信中的Variable Optical Attenuator和可能的电子工程中的Voltage-Operated Amplifier。 还需要考虑用户可能的背景,如果他们从事网络或通信工作,Variable Optical Attenuator会是更相关的解释。而如果他们涉及电子电路设计,可能会遇到Voltage-Operated Amplifier,但需要进一步确认是否该缩写被广泛使用。 总结,技术上下文中VOA的主要含义是Variable Optical Attenuator,其次是可能的Voltage-Operated Amplifier。需要将这些信息整理成清晰的回答,分点说明,并附上相关应用和公式示例。同时,确保遵循格式要求,如数学公式使用$符号包裹,代码块使用三个反引号等。 最后,生成相关问题时要基于用户的问题和回答内容,可能涉及VOA的技术应用、工作原理,或与其他缩写对比的问题。例如,询问VOA在光纤网络中的作用,如何调节光信号,以及与固定光衰减器的区别等。</think>在技术领域中,**VOA** 通常指 **Variable Optical Attenuator**(可变光衰减器),是光纤通信系统中的关键组件。以下是具体解释和应用场景: --- ### 1. **技术定义与功能** VOA 通过动态调节光信号的功率强度,确保光纤网络中的信号平衡。其核心原理基于机械、热光或电光效应调整光路损耗,数学上可表示为: $$ P_{out} = P_{in} \times 10^{-A/10} $$ 其中 $A$ 为衰减值(单位:分贝 dB),$P_{in}$ 和 $P_{out}$ 分别为输入/输出光功率。 --- ### 2. **应用场景** - **波分复用系统(WDM)**:均衡不同波长通道的光功率,避免接收端过载。 - **光放大器控制**:防止掺铒光纤放大器(EDFA)因输入功率波动导致的非线性失真。 - **光模块测试**:校准光器件性能时精确控制输入功率。 --- ### 3. **实现类型** ```python # 示例:基于 MEMS 的 VOA 控制代码(简化逻辑) def set_attenuation(voltage, target_dB): current_dB = read_current_attenuation() while abs(current_dB - target_dB) > 0.1: adjust_voltage(voltage) current_dB = read_current_attenuation() return "Attenuation set to {} dB".format(target_dB) ``` - **机械式**:通过移动挡片物理遮挡光路。 - **热光式**:利用材料折射率随温度变化的特性(如硅基波导)。 - **电光式**:施加电压改变晶体折射率(如铌酸锂器件)。 --- ### 4. **关键参数** - 衰减范围(如 0–30 dB) - 响应时间(通常 <10 ms) - 波长依赖性(如 1520–1620 nm) ---
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