基于红外通信的数据采集系统

随着红外技术的发展,红外通信已经成为越来越普及的无线通信方式。红外通信是以红外线为载体来传送数据信息,具有操作简单、可靠性高、功耗低、抗干扰能力强、空间接入灵活、无需连接线等优点,所以越来越受到重视。数据采集系统是在多种场合都有着重要应用的系统,现场的某些参数要通过传感器采集后送到前台机的数据接收端进行初步的处理,然后前台机要把这些数据传输给后台机进行更进一步的分析和处理,以便于掌握现场的实际情况并采取进一步的措施。     

中国居民家庭收入代际传递性分析

本文通过对父子收入代际弹性和家庭收入代际弹性的研究,发现子女收入很大程度上受到父亲收入或家庭收入的影响,证明了中国居民收入代际之间存在着较为明显的传递效应,特别是低收入群体。通过内外因分析,可以发现教育成为影响中国居民收入代际传递现象的重要因素。教育是一种重要的代际流动机制,个人教育水平提高和教育环境的公平可以使低收入群体有机会流向更高收入阶层。     

日照港煤码头国内环境分析与竞争力提升策略

在经济全球化、一体化时代,随着船运公司和货主的实力增强,港口之间的竞争日趋激烈,港口已不再像过去那样具有较强的自然垄断力。本文以日照港为例,分析我国北方港口煤码头运输现状,从港口文化、港口战略、生产管理、资源整合、硬件设施、政策因素等六个方面研究提升港口综合竞争力的途径。     

南极磷虾渔业监管体系浅析

渔业监管体系是渔业管理的实施机制,是渔业管理体系不可或缺的组成部分,而有效的渔业监管则是渔业有序发展的重要保障.在渔业管理领域,南极海洋生物资源养护委员会(CCAMLR)一直处于国际前沿,是全球渔业资源管理的典范.论文以CCAMLR与磷虾渔业有关的养护措施、条例、决议及制度等为基础,将磷虾渔业监管体系按监测、管控与监督三个部分进行了系统归纳和分析,以供我国渔业监管参考.     

粮食中伏马毒素B1、B2的免疫亲和净化超高效液相色谱测定

建立了免疫亲和柱净化-超高效液相色谱法快速测定粮食中伏马毒素B1、B2的检测方法.样品经提取后,用免疫亲和柱净化、浓缩,Waters Acquity UPLC BEH C18(50 mm×2.1 mm,1.7 μm)色谱柱分离,以甲醇/磷酸二氢钠溶液(77/23,v/v)为流动相、流速为0.2 mL/min、进样量为1μL,用Acquity荧光检测器激发波长为310nm、发射波长为435 nm处进行检测,无需衍生,伏马毒素B1、B2的保留时间小于6.5 min,从样品前处理到分析整个过程小于45 min.根据3倍信噪比的峰响应值,确定伏马毒素B1、B2的检出限为0.05 ng,在0.25～10.0 ng范围内呈线性相关,相关系数R2值分别为0.9972和0.9999;FB1和FB2在粮食样品中加标回收率分别为70.0％～100.5％和74.8％～96.0％,精密度分别为2.2％～5.5％和4.3％～7.4％.本方法简便快速、灵敏度高、重现性好、溶剂用量少,适用于粮食中伏马毒素B1、B2的快速测定.     

留住核心人才

核心人才是指有着较强的专业技术或技能、丰富的从业经验及杰出的经营管理才能,对企业的生产经营起关键作用的人才。核心人才是企业的精英和骨干,一旦离开,在短时间内很难找到合适的人来取代,同时核心人才的离开也往往伴随着企业核心技术的流失。据美国一项研究,一个人离职可能会使公司损失5万～10万美元。有关调查资料也显示:人才流失以后的置换成本相当高,替换雇员的成本可以高达辞职者工资的150%。因此,企业与其挖空心思招聘人才,不如想办法留住现有人才。一、树立21世纪的科学人才观1.树立“以人为本”的观念。我们知道,在市场上竞争的…     

明清民国时期大陆泽流域县际用水秩序与社会互动

以往研究着重于大陆泽流域县域内以"镰"为中心的水利共同体,而忽视了整个流域内县际之间的水资源分配与用水互动问题。自明代水利兴起以来,这一流域县际之间曾存在数个用水规章,清代国家营田又曾短期强化过县际均水秩序。不过因流域自然地理因素和政区界限的作用,这一流域县际之间用水秩序一直未得到切实而持久的执行。同时,地方士绅与棍徒类豪民因自身利益的不同,不时打破常规,甚至直接掌控闸堰、灌渠,从而加剧了县际用水的矛盾。他们也不再是乡民的代言人和沟通官府的中介,反而是水利社会的蠹虫和令官府头痛的对象。用水纠纷和诉诸官府成为这一地区围绕着水利开发而产生的县际社会互动之主要特征。     

The role of generally accepted reporting methods in the public sector: An empirical test

This study explores the role of standard or generally accepted accounting and reporting methods in the public sector. It differs from prior studies that address public sector accounting issues in that it considers more directly how the political process influences decisions to report financial information. The primary contention is that adopting standard reporting methods reduces costs to public officials that arise from factors that characterize political markets. Empirical evidence based on data from the state governments is consistent with this contention, but theoretical and methodological problems restrict our ability to ascertain which specific factors are relevant.     

Implied Lévy volatility

We study the cause of large fluctuations in prices on the London Stock Exchange. This is done at the microscopic level of individual events, where an event is the placement or cancellation of an order to buy or sell. We show that price fluctuations caused by individual market orders are essentially independent of the volume of orders. Instead, large price fluctuations are driven by liquidity fluctuations, variations in the market's ability to absorb new orders. Even for the most liquid stocks there can be substantial gaps in the order book, corresponding to a block of adjacent price levels containing no quotes. When such a gap exists next to the best price, a new order can remove the best quote, triggering a large midpoint price change. Thus, the distribution of large price changes merely reflects the distribution of gaps in the limit order book. This is a finite size effect, caused by the granularity of order flow: in a market where participants place many small orders uniformly across prices, such large price fluctuations would not happen. We show that this also explains price fluctuations on longer timescales. In addition, we present results suggesting that the risk profile varies from stock to stock, and is not universal: lightly traded stocks tend to have more extreme risks.