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关键词： 消费者信心指数   居民消费   Carroll两步处理法   方向分析  

摘要： 文章基于2001-2011年的季度数据,采用Carroll两步处理法和非参数方向分析分别检验我国消费者信心指数对居民消费的预测作用及其有效性,结果表明:(1)控制变量为可支配收入或历史消费时,消费者信心指数及其分指数对居民总消费和衣着、居住、杂项商品与服务分项消费的变动存在解释能力,对食品、家庭设备用品及服务分项消费几乎无解释能力,对其他分项消费的解释能力随控制变量的不同而不同;(2)消费者信心指数及其分指数可有效预测居民总消费、杂项商品及服务消费等的变动。

关键词： 临床   医学检验   地位和作用  

摘要： 医学检验在临床中十分重要,是确诊疾病、进行治疗的关键所在。本文从临床生物化学检验和微生物学两个方面进行探析其地位和作用,并提出临床和医学检验想结合的措施。

关键词： 计价货币   新开放经济宏观经济学   局部均衡   一般均衡   微观基础  

摘要： 国际贸易中计价货币选择决定因素的研究,多基于新开放经济宏观经济学理论,着眼于计价货币选择的微观基础,以厂商预期利润最大化为目标,采用局部均衡或一般均衡分析法展开论证。既有文献认为,贸易双方影响市场的能力、金融市场的健康完善程度是影响计价货币选择的主要因素。但这些研究在理论假设、研究视野、实证检验及覆盖面等方面仍有缺憾,对发展中国家尤其对中国的情况缺乏深入探讨,亟须后续研究重点突破。

关键词： Linear manifold   Gram matrix   Kernel function   Tikhonov regularization   NEAREST-NEIGHBOR CLASSIFICATION   SUPPORT VECTOR MACHINES   RECOGNITION   KERNEL   CLASSIFIERS  

摘要： A classifier is proposed wherein the distances from samples to linear manifolds (DSL) are used to perform classification. For each class, a linear manifold is built, whose dimension is high enough to pass all the training samples of the class. The distance from a query sample to a linear manifold is converted to the distance from a point to a linear subspace. And a simple and stable formula is derived to calculate the distance by virtue of the geometrical fundamental of the Gram matrix as well as the regularization technique. The query sample is assigned into the class whose linear manifold is the nearest. On one synthetic data set, thirteen binary-class data sets as well as six multi-class data sets, the experimental results show that the classification performance of DSL is of competence. On most of the data sets, DSL outperforms the comparing classifiers based on k nearest samples or subspaces, and is even superior to support vector machines on some data sets. Further experiment demonstrates that the test efficiency of DSL is also competitive to kNN and the related state-of-the-art classifiers on many data sets.

关键词： Breeding soundness evaluation   Bull sperm   Sperm morphology   Transrectal massage   Semen collection   Morphological classification system   ELECTROEJACULATION   SPERM  

摘要： This experiment was conducted to compare the accepted Field system of bull breeding soundness evaluation (BBSE) utilized by veterinarians in Canada with the centralized Swedish (Lab) system. To be classified as a satisfactory potential breeder, both systems require that bulls must have >= 70% morphologically normal sperm; however, minimum progressively motile sperm (>= 60% - Field; >= 30% - Lab) and maximum sperm class abnormalities proportions differ (<20% - Field; <15% - Lab). Semen was collected by transrectal massage (TM) from 54 sexually mature beef bulls. The percent progressively motile sperm was determined within minutes of collection and these data were shared. Sperm morphology was evaluated independently utilizing slide staining and microscopic assessment techniques typically used for the evaluation of bull semen within the respective countries. Mean progressively motile sperm was 45% ( 23.8%). The mean proportion of normal sperm recorded in the Field (83.6 +/- 12.1%) was greater than the Lab (71.1 +/- 18.2%) (P < 0.001) with more sperm head abnormalities recorded in the Lab (13.6 +/- 11.4) than the Field (2.4 +/- 2.8) (P < 0.01). The number of bulls exceeding the >= 70% morphologically normal sperm was 51 (94.4%) in the Field versus 36 (66.7%) in the Lab (kappa = 0.21). Only 13 bulls were classified as satisfactory potential breeders by both systems (kappa = 0.15). Efforts to improve and standardize the evaluation of bull sperm morphology are needed, and the use of >= 30% progressively motile sperm threshold for TM-derived samples is recommended. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Stretch rate   Particle image velocimetry   Flame-vortex interaction   Strained flame speed   Consumption speed   Mode transition   PARTICLE IMAGE VELOCIMETRY   MODEL   INSTABILITY   MECHANISM   VELOCITY  

摘要： In this paper, we experimentally investigate the combustion dynamics in lean premixed flames in a laboratory scale backward-facing step combustor in which flame-vortex driven dynamics are observed. A series of tests was conducted using propane/hydrogen/air mixtures for various mixture compositions at the inlet temperature ranging from 300 K to 500 K and at atmospheric pressure. Pressure measurements and high speed particle image velocimetry (PIV) are used to generate pressure response curves and phase-averaged vorticity and streamlines as well as the instantaneous flame front, respectively, which describe unsteady flame and flow dynamics in each operating regime. This work was motivated in part by our earlier study where we showed that the strained flame consumption speed S-c can be used to collapse the pressure response curves over a wide range of operating conditions. In previous studies, the stretch rate at which S-c was computed was determined by trial and error. In this study, flame stretch is estimated using the instantaneous flame front and velocity field from the PIV measurement. Independently, we also use computed strained flame speed and the experimental data to determine the characteristic values of stretch rate near the mode transition points at which the flame configuration changes. We show that a common value of the characteristic stretch rate exists across all the flame configurations. The consumption speed computed at the characteristic stretch rate captures the impact of different operating parameters on the combustor dynamics. These results suggest that the unsteady interactions between the turbulent flow and the flame dynamics can be encapsulated in the characteristic stretch rate, which governs the critical flame speed at the mode transitions and thereby plays an important role in determining the stability characteristics of the combustor. (c) 2013 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

关键词： 融资租赁   租赁物   资产信用   租赁协议   行政许可   无效行为   恶意串通   赔偿损失   交易方式   审批机关  

摘要： 经济的快速发展扩大了对融资的需求,也催生了各种各样的资金融通方式,融资租赁即为其中最为独特的一种。它是指出租人根据承租人对出卖人、租赁物的选择,向出卖人购买租赁物,提供给承租人使用,承租人向出租人支付租金的行为。融资租赁集借贷、租赁、买卖于一体,是将融资与融物结合在一起的交易方式。基于融资租赁产品独具"融资+融物"优势,以"资产信用"为基础,能有效地控制资金走向。

关键词： 跨界活动   企业间知识利用   边缘知识  

摘要： 服务外包活动形成的企业间合作,是为了实现跨越组织边界的知识利用。但在合作初期因为发包企业和接包企业之间欠缺合作经验与共享知识,尚未建立有效的治理机制,会阻碍外包项目的顺利实施,进而影响建立面向长期的双边关系。基于企业间知识管理的视角,从服务外包活动中双边合作关系以及知识转移和利用的特殊性出发,文章分析认为,通过跨越组织边界和知识边界实施的跨界活动,接包企业项目管理者能承担起任务导向和情绪纽带的功能,"粘合"这种松散耦合的企业间关系,从而促进双方传递边缘知识、协调整合运营活动、识别问题和解决冲突,提高项目合作绩效。实证结果也支持了个体跨界者通过促进企业间知识利用效率对外包活动绩效产生正向影响的基本假设。

关键词： 自然辩证法   整体分析   检验结果   疾病诊断  

摘要： 检验医学在疾病预防、诊断、疗效和预后的判断、健康状况的评价等方面发挥着巨大的作用。进入21世纪以来,随着科学技术的飞速发展,检验诊断技术日新月异,全自动化、智能化、集成化、网络化仪器相继问世,为临床提供了更多的诊断依据,70%～85%的诊断和治疗决策都依据检验结果。对于检验结果在疾病诊断中的作用,需要一分为二地看。