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161.
新闻语体的句子应该比其他语体的句子短,这是由新闻的易读性决定的。但是目前的一些新闻语言研究中,统计出的句子比其他语体的句子还要长几倍。一些新闻语言研究中同时以单句和复句为单位。单句和复句在语法结构上不是同一层级的语言单位,同时作为计算单位,是违反逻辑的。语法系统中,小句是基本的句子,是传递信息的基本单位。新闻语言研究中也应以小句为计算单位。  相似文献   
162.
In a recently published note in this journal the need for independent control of the production rate (R) and production time (L) was established in order to adapt the economic production quantity (EPQ) model in JIT settings. In this comment we aim to improve the relevance of EPQ in a JIT environment. We focus on two issues, namely, modelling the production rate as a decision variable and also deriving an expession for the optimal number of batches (n* ) for the raw materials and/or subcomponents needed.  相似文献   
163.
新世纪中国生态批评与生态美学的发展及其问题域   总被引:1,自引:0,他引:1  
20世纪90年代开始,生态美学、生态文艺学、生态批评的研究迅速成为中国文论研究中广受关注的前沿和热点问题之一。在经过了萌发和草创阶段之后,目前已进入了学理的探索、丰富和深化阶段。尽管中国生态批评及其理论形态的生态文艺学、生态美学目前尚未完全发展成熟,但理论上的尝试和建设及争鸣已开启了学科建构的新视角、新观点,极大地推动了学科的发展,中国的生态批评和生态美学研究已初见规模,并必将在新世纪中国文论建设中承担起自己的责任。  相似文献   
164.
网上银行顾客感知服务质量影响因素研究   总被引:1,自引:0,他引:1  
通过文献研究和深度访谈,提炼出可能影响网上银行顾客感知服务质量的19个因素,通过探索性因子分析,将这19个因素归纳为经济性、易用性、履行性、安全性和响应性。通过相关分析和多元回归分析发现,有4类因素与网上银行顾客感知服务质量呈显著正相关,依次是经济性、易用性、履行性和安全性。通过对我国主要网上银行服务质量测评发现,当前我国网上银行服务质量不高,且各家网上银行服务质量存在明显差异。  相似文献   
165.
巴洛克文学曾受到文学批评史的不公正对待已是不争的事实。可是文学史的发展轨迹最终表明巴洛克文学具有多元文化价值、强大的生命力和不容忽视的影响场域。巴洛克文学的多元文化价值表现在:其一,生动再现17世纪欧洲各国的社会生活现实;其二,体现多元化的审美文化追求。巴洛克文学的影响场域表现为后世作家对其思想和艺术手法的借鉴、移植和化用,虽然亦存在着难以融合的断裂感和新异感。另外,这种影响还体现为一种追新逐异、兼收并蓄的"巴洛克精神"的广泛渗透。  相似文献   
166.
Building on recent European studies, we used the Survey of Income and Program Participation to provide the first analysis of fertility differences between groups of US college graduates by their undergraduate field of study. We used multilevel event-history models to investigate possible institutional and selection mechanisms linking field of study to delayed fertility and childlessness. The results are consistent with those found for Europe in showing an overall difference of 10 percentage points between levels of childlessness across fields, with the lowest levels occurring for women in health and education, intermediate levels for women in science and technology, and the highest levels for women in arts and social sciences. The mediating roles of the following field characteristics were assessed: motherhood employment penalties; percentage of men; family attitudes; and marriage patterns. Childlessness was higher among women in fields with a moderate representation of men, less traditional family attitudes, and late age at first marriage.  相似文献   
167.
Ryff’s (1989b) Psychological Well-Being (PWB) scales measure six related constructs of human functioning. The present paper examined the validity of Ryff’s 6-factor PWB model, using data from a life events study (N = 401) and an organisational climate study (N = 679). Previous validation studies, using Confirmatory Factor Analysis (CFA), have identified alternative PWB models, but limitations include the use of shorter scale versions with items relating to a number of life domains within the same PWB factor, and failure to examine the influence of participants’ socio-demographic characteristics on PWB. In this study, Exploratory Factor Analysis (EFA) mostly found consistency in the PWB items and structure between the two studies whereby a 3-factor model delineated between items relating to Autonomy, Positive Relations and a super-ordinate factor comprising the other PWB factors. Using CFA, Goodness of Fit indices reached acceptable levels for the adjusted PWB model identified by the EFA, whilst differences between adjusted models of PWB previously identified in the literature were hardly evident. Post-hoc analysis by gender demonstrated socio-demographic effects on the structure and items that comprise PWB. Further development of PWB measures is needed to reflect its hierarchical and multi-dimensional nature. In the scales’ current form, the construct validation of the PWB factors will continue to be problematic and will fail to adequately evaluate the nature and impact of PWB.  相似文献   
168.
A substantial degree of uncertainty exists surrounding the reconstruction of events based on memory recall. This form of measurement error affects the performance of structured interviews such as the Composite International Diagnostic Interview (CIDI), an important tool to assess mental health in the community. Measurement error probably explains the discrepancy in estimates between longitudinal studies with repeated assessments (the gold-standard), yielding approximately constant rates of depression, versus cross-sectional studies which often find increasing rates closer in time to the interview. Repeated assessments of current status (or recent history) are more reliable than reconstruction of a person's psychiatric history based on a single interview. In this paper, we demonstrate a method of estimating a time-varying measurement error distribution in the age of onset of an initial depressive episode, as diagnosed by the CIDI, based on an assumption regarding age-specific incidence rates. High-dimensional non-parametric estimation is achieved by the EM-algorithm with smoothing. The method is applied to data from a Norwegian mental health survey in 2000. The measurement error distribution changes dramatically from 1980 to 2000, with increasing variance and greater bias further away in time from the interview. Some influence of the measurement error on already published results is found.  相似文献   
169.
Criteria to protect aquatic life are intended to protect diverse ecosystems, but in practice are usually developed from compilations of single‐species toxicity tests using standard test organisms that were tested in laboratory environments. Species sensitivity distributions (SSDs) developed from these compilations are extrapolated to set aquatic ecosystem criteria. The protectiveness of the approach was critically reviewed with a chronic SSD for cadmium comprising 27 species within 21 genera. Within the data set, one genus had lower cadmium effects concentrations than the SSD fifth percentile‐based criterion, so in theory this genus, the amphipod Hyalella, could be lost or at least allowed some level of harm by this criteria approach. However, population matrix modeling projected only slightly increased extinction risks for a temperate Hyalella population under scenarios similar to the SSD fifth percentile criterion. The criterion value was further compared to cadmium effects concentrations in ecosystem experiments and field studies. Generally, few adverse effects were inferred from ecosystem experiments at concentrations less than the SSD fifth percentile criterion. Exceptions were behavioral impairments in simplified food web studies. No adverse effects were apparent in field studies under conditions that seldom exceeded the criterion. At concentrations greater than the SSD fifth percentile, the magnitudes of adverse effects in the field studies were roughly proportional to the laboratory‐based fraction of species with adverse effects in the SSD. Overall, the modeling and field validation comparisons of the chronic criterion values generally supported the relevance and protectiveness of the SSD fifth percentile approach with cadmium.  相似文献   
170.
针对纸机日益高速化、大型化的发展趋势,设计了国内先进的全数字化通信网络传动控制系统。系统采用西门子全集成自动化解决方案,实现造纸生产过程的全线集成控制。高可靠的工业现场总线PROFIBUS—DP和工业以太网相结合的网络结构,有效地实现了数据共享,全面解决了整个工艺过程的控制。文章详细介绍了控制系统的配置和功能,重点阐述了速度链、负荷分配控制、张力控制等主要控制原理。  相似文献   
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