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951.
952.
A shop floor control system (SFCS), which is the most important component of any production control system, ff has a direct e ect on the productivity of a tool room. The SFCS presented in this paper aims at streamlining various tool room activities, such as process planning, operations scheduling, loading, progress monitoring, and performance monitoring. The system discussed in this paper is characterized by simplicity and is user friendly. Basic information, consisting of three types of information (order details, process details, and part details), is input through interactive dialogue sessions. On-line updating of the process information is carried out, again through interactive dialogue sessions. The basic input to the system along with the on-line updating enables a number of useful and important reports and documents to be generated ff by the system for e ective control of the shop floor. The reports generated include operations scheduling, process sheet, part list, ffi job card, load pending report, e ciency report, etc. This SFCS is developed for a medium sized tool room in an automotive company and its successful implemention reduced paperwork and improved resource management and has resulted in productivity. It can be said that this system offers a first venture into computer integrated manufacturing (CIM) for a tool room. 相似文献
953.
On-time delivery is the need for customer satisfaction which is a critical factor in the survival of the semiconductor industry. The on-time-delivery performance of the whole semiconductor turnkey service depends on the performance of the back-end factories. Unfortunately, undesirable and inevitable production variations make it difficult to maintain and improve a factory's performance and more objectives such as cycle time, throughput rate and the due-date accuracy need to be simultaneously considered. This paper presents an exception management model in order to compromise the contradicting needs of delivery accuracy, throughput rate and cycle time. The exception model can be divided into three parts: (1) an integrated performance index is proposed to compromise multiple performance measures; (2) an AWDL (available WIP deviation level) determination model is designed to gather proper AWDLs for triggering exceptions and (3) a WIP correction action is proposed to make abnormal WIP levels back to normal levels as soon as possible. To evaluate the proposed WIP exception management model, a simulation model is constructed and experiments are then conducted. The simulation results show that the proposed model helps back-end factories to set proper exception triggering conditions, reduce uncertainty occurrences and achieve better performances on due dates. 相似文献
954.
Agnieszka D. Hunka Mattia Meli Amalie Thit Annemette Palmqvist Pernille Thorbek Valery E. Forbes 《Risk analysis》2013,33(1):68-79
The article closely examines the role of mechanistic effect models (e.g., population models) in the European environmental risk assessment (ERA) of pesticides. We studied perspectives of three stakeholder groups on population modeling in ERA of pesticides. Forty‐three in‐depth, semi‐structured interviews were conducted with stakeholders from regulatory authorities, industry, and academia all over Europe. The key informant approach was employed in recruiting our participants. They were first identified as key stakeholders in the field and then sampled by means of a purposive sampling, where each stakeholder identified as important by others was interviewed and asked to suggest another potential participant for our study. Our results show that participants, although having different institutional backgrounds often presented similar perspectives and concerns about modeling. Analysis of repeating ideas and keywords revealed that all stakeholders had very high and often contradicting expectations from models. Still, all three groups expected effect models to become integrated in future ERA of pesticides. Main hopes associated with effect models were to reduce the amount of expensive and complex testing and field monitoring, both at the product development stage, and as an aid to develop mitigation measures. Our analysis suggests that, although the needs of stakeholders often overlapped, subtle differences and lack of trust hinder the process of introducing mechanistic effect models into ERA. 相似文献
955.
William D. Nordhaus 《商业与经济统计学杂志》2013,31(2):182-187
This note examines an augmented cost-of-living index (ACOLI) for the purpose of accounting for “augmented consumption” in real-income measures. Well-being includes not only conventional consumer purchases but also goods and services provided by employers, by mandated social regulations, and by tax-financed public goods. Because augmented consumption is often provided in ways that raise prices but not market incomes, deflating with conventional price indexes may understate real income growth. An exploratory application of the ACOLI approach to the United States during the 1960–1997 period suggests that the Consumer Price Index has grown about 19% faster than the ACOLI. This correction would reduce the estimated cost-of-living increase by .47% per year over the last 37 years. 相似文献
956.
Likelihood ratio tests for the homogeneity of k normal means with the alternative restricted by an increasing trend are considered as well as the likelihood ratio tests of the null hypothesis that the means satisfy the trend. While the work is primarily a survey of results concerning the power functions of these tests, the extensions of some results to the case of not necessarily equal sample sizes are presented. For the case of known or unknown population variances, exact expressions are given for the power functions for k=3,4, and approximations are discussed for larger k. The topics of consistency, bias and monotonicity of the power functions are included. Also, Bartholomew's conjectures concerning minimal and maximal powers are investigated, with results of a new numerical study given. 相似文献
957.
This study examines the relationship between financial strain and depressive symptoms in later life, and potential psychosocial
mediators of this relationship. Drawing on a sample of 214 low-income Latino older adults, we used structural equation modeling
to test the direct effect of chronic financial strain on depressive symptomatology, and the indirect effects via social support,
negative interaction, and coping styles. Findings indicated that financial strain increased the level of depressive symptoms
among this sample. Avoidance and approach-related coping styles emerged as independent determinants of depressive symptoms
albeit in opposite directions; higher levels of avoidance coping was associated with higher levels of depressive symptoms.
Contrary to previous findings on the general population, findings from the current study indicate that social support and
negative interaction were not directly associated with depressive symptoms. Financial strain mediated the effect of sociocultural
(nativity status, years of U.S. residence) and social status factors (age, education) on depressive symptoms. This study highlights
the differential impact of financial strain and coping styles on psychological well-being, and the potential psychosocial
targets of interventions for older adults with chronic health care conditions. 相似文献
958.
959.
960.
Nicholas T. Longford 《Journal of applied statistics》2009,36(11):1259-1265
This article is concerned with the analysis of a random sample from a binomial distribution when all the outcomes are zero (or unity). We discuss how elicitation of the prior can be reduced to asking the expert whether (and which of) the so-called borderline or equilibrium priors are plausible. 相似文献