空调梯级能源利用的分析与探讨

本方案充分利用发电机余热来达到空调节能的目的,实现能源梯级利用。可大幅度节省运行费用,均衡能源结构,削减夏季电力峰值,填补夏季燃气谷值,减少公用事业投资,属合理用能环保设备,被能源专家大力提倡。     

东莞溺死案多发河段硅藻种群分布及其法医学意义

目的调查东莞溺死案多发河段硅藻种群分布,探讨其在溺死地点推断中的意义。方法于2009年6月至9月收集东莞市东江沙田、道滘、麻涌、石碣、石龙、茶山和企石共7个河段采样点江水样本126份,并收集2例已知落水地点溺死尸体;制作各样本硅藻涂片,计算样本间Sprensen相似系数及弦平方距离(SCD),并进行聚类分析。结果 126份水样中共鉴定出70种硅藻,其中优势度>0.02的优势种群有4种;2个案例样本分别与道滘和石碣河段样本的相似度最高,与实际落水地点基本一致。结论建立区域性溺死多发河段硅藻数据库,利用Sprensen相似系数及SCD值及聚类分析进行落水地点推断具有一定可行性。     

运动神经元病五脏相关性研究

目的 研究运动神经元病患者五脏之间相互影响的规律.方法 从广州中医药大学第一附属医院病案室收集161例运动神经元病患者的中医证候资料,通过SAS软件对五脏各自证型进行典型相关分析.结果 从两脏之间的直接效应看,心与肾、脾与肺的直接通径系数较大,分别是0.853 9和0.740 3,肺与肾、心与肺、脾与肾的直接通径系数次...     

见怪不怪与其怪自败

中国的基尼系数从20世纪80年代的0 25上升到目前的0 458,并且还有进一步扩大的趋势。进入20世纪90年代中期以后,我国城市贫困的状况持续恶化,农村贫困的缓解也面临着极大的困难。即便是按照我们自己制定的非常之低的贫困线来衡量,目前城乡绝对贫困人口的数量也在1亿人上下,如果按照联合国制定的每人每天1美元来衡量,中国的贫困人口总量将达到2 5亿人的规模。     

Science and International Environmental Nonregimes: The Case of Arctic Haze

Dimitrov et al. argue that nonregimes are a worthy object of research attention that can contribute to international regime theory. Case studies, however, are still sparse. In this article, I examine Arctic haze, an issue area where a transnational environmental problem existed but no regime formed. Arctic haze was (re‐)discovered in 1971 but by 2000, the window of opportunity to form a regime had closed. What factors explain why an Arctic haze regime was not formed between 1971 and 2000? I claim science‐based factors play the dominant role. An analytical approach applicable to the science‐policy interface was employed. Using this approach, I conclude that the Arctic haze nonregime is best explained by the absence of scientifically documented and compelling transboundary consequences to ecosystems and humans. This is a product of the unique nature of the Arctic atmosphere.     

A Prototype of Mathematical Treatment of Pen Pressure Data for Signature Verification

A prototype using simple mathematical treatment of the pen pressure data recorded by a digital pen movement recording device was derived. In this study, a total of 48 sets of signature and initial specimens were collected. Pearson's correlation coefficient was used to compare the data of the pen pressure patterns. From the 820 pair comparisons of the 48 sets of genuine signatures, a high degree of matching was found in which 95.4% (782 pairs) and 80% (656 pairs) had rPA > 0.7 and rPA > 0.8, respectively. In the comparison of the 23 forged signatures with their corresponding control signatures, 20 of them (89.2% of pairs) had rPA values < 0.6, showing a lower degree of matching when compared with the results of the genuine signatures. The prototype could be used as a complementary technique to improve the objectivity of signature examination and also has a good potential to be developed as a tool for automated signature identification.     

中国农村居民消费结构分析

运用统计学理论,动态分析中国农村居民的消费结构及影响因素,可为提高农村居民的生活质量提供参考。[1]研究结果表明:1990年以来,农村居民恩格尔系数处于递减的趋势,食品、衣着比例减少,医疗、交通和通讯比例增加,消费结构有所改善,但2005年以后,农村居民在文教娱乐方面的支出比重有下降趋势,此现象值得关注。建议通过提高农民科学素养、拓宽增收渠道等措施增加农民收入,促进消费结构的优化。     

电动两轮车侧翻倒地滑动摩擦系数实验研究

目的两轮车侧翻倒地后的滑行摩擦系数是利用两轮车碰撞后倒地滑行距离进行速度计算的关键参数,论文通过试验研究提出用于道路交通事故速度计算的电动两轮车侧翻倒地滑动摩擦系数。方法在综合分析电动两轮车侧倒滑行摩擦系数影响因素的基础上,利用正交试验设计摩擦系数实验方案,并采用实车牵引的方法,在不同速度条件下,分别在干燥、潮湿的沥青混凝土路面及水泥混凝土路面上进行实验。结果实验所得数据显示,电动两轮车侧翻倒地滑动摩擦系数的范围为0.40～0.60。结论通过对所得数据进行处理,提出适用于电动两轮车交通事故再现的摩擦系数范围。     

Aviation security and terrorism

Abstract

The author asserts that a sophisticated sabotage threat to U.S. international civil aviation has been well known to the U.S. government and air carriers since the early 1980s. He believes that both the U.S. government and air carriers have failed to do enough to counter this sabotage threat. He cites the findings of the President's Commission on Aviation Security and Terrorism (May 1990), and the enactment of the Aviation Security Improvement Act (Nov. 1990) to support his beliefs. The author concludes by providing a recipe for corrective action.     

Individual Camera Identification Using Correlation of Fixed Pattern Noise in Image Sensors

Abstract:  This paper presents results of experiments related to individual video camera identification using a correlation coefficient of fixed pattern noise (FPN) in image sensors. Five color charge-coupled device (CCD) modules of the same brand were examined. Images were captured using a 12-bit monochrome video capture board and stored in a personal computer. For each module, 100 frames were captured. They were integrated to obtain FPN. The results show that a specific CCD module was distinguished among the five modules by analyzing the normalized correlation coefficient. The temporal change of the correlation coefficient during several days had only a negligible effect on identifying the modules. Furthermore, a positive relation was found between the correlation coefficient of the same modules and the number of frames that were used for image integration. Consequently, precise individual camera identification is enhanced by acquisition of as many frames as possible.