首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   42篇
  免费   2篇
  国内免费   3篇
工业技术   47篇
  2024年   1篇
  2023年   1篇
  2022年   1篇
  2021年   2篇
  2020年   1篇
  2017年   1篇
  2016年   3篇
  2015年   2篇
  2014年   2篇
  2013年   2篇
  2012年   5篇
  2011年   2篇
  2010年   4篇
  2009年   2篇
  2008年   2篇
  2007年   1篇
  2006年   4篇
  2005年   2篇
  2004年   3篇
  2003年   1篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
  1996年   1篇
排序方式: 共有47条查询结果,搜索用时 312 毫秒
1.
In this paper we study two generalizations of the well known unrelated parallel machines scheduling problem under makespan (Cmax) minimization. First, a situation in which not every available parallel machine should be used and it is desirable to employ only a subset of the parallel machines. This is referred to as “Not All Machines” or NAM in short. This environment applies frequently in production shops where capacity exceeds demand or when production capacity can be lent to third companies. Also, NAM can be used to increase production capacity and it is not clear how many additional machines should be acquired. The second studied generalization has been referred to as “Not All Jobs” or NAJ. Here, there is no obligation to process all available jobs. We propose Mixed Integer Programming mathematical formulations for both NAM and NAJ, and it is shown that the latter can be effectively solved with modern commercial solvers. We also present three algorithms to solve the NAM problem. These algorithms are compared with the proposed MIP formulation when solved with IBM ILOG CPLEX 12.1. Comprehensive computational and statistical experiments prove that our proposed algorithms significantly improve the results given by the solver.  相似文献   
2.
Despite a distinguished heritage of learning in the Middle East, the expansion of provision for higher education is currently at an unprecedented scale. The Gulf States, in particular, are seeking to keep up with accelerated population growth and a demographic ‘youth bulge’. Guest-Editor Kevin Mitchell describes the architectural approaches employed in the design of institutions in the region from the first universities in Saudi Arabia to Foster + Partners's ground-breaking sustainable design for the Masdar Institute in Abu Dhabi and future projects.  相似文献   
3.
In this paper, we study the problem of auctioning a kind of continuous homogeneous divisible goods, and present a multi-stage sequential auction mechanism of divisible goods under uniform price. In this mechanism, the auction process is divided into multiple stages, all bidders satisfy the sequential rationality conditions, all bidders are asymmetric, every bidder is allowed to submit a nonincreasing continuous demand function in each round bidding, every bidder’s valuation to per unit of the goods is independent private information, and if a bidder does not obtain the quantity he wants in former stage auction, he still have another opportunity to obtain some quantity in the later stage auction. For this mechanism, we explore the formation process and composition of equilibrium points in each stage auction, and discuss the optimal strategy selection for bidders, then give the detail steps and an application example to show how to implement this multi-stage sequential auction mechanism. The conclusions can be drawn that our auction mechanism is an efficient incentive mechanism, and can effectively reduce many underpricing equilibrium and can yield higher expected income than a single uniform price auction for the auctioneer. It also can avoid the occurrence of failure auction (equilibrium does not exist), and effectively extend and improve the traditional single stage uniform price auction mechanism.  相似文献   
4.
本文介绍非接触式单探头超声波物位检测仪的原理,分析影响检测仪正常使用的因素及其安装要求。  相似文献   
5.
Target design methodologies (DfX) were developed to cope with specific engineering design issues such as cost-effectiveness, manufacturability, assemblability, maintainability, among others. However, DfX methodologies are undergoing the lack of real integration with 3D CAD systems. Their principles are currently applied downstream of the 3D modelling by following the well-known rules available from the literature and engineers’ know-how (tacit internal knowledge).This paper provides a method to formalize complex DfX engineering knowledge into explicit knowledge that can be reused for Advanced Engineering Informatics to aid designers and engineers in developing mechanical products. This research work wants to define a general method (ontology) able to couple DfX design guidelines (engineering knowledge) with geometrical product features of a product 3D model (engineering parametric data). A common layer for all DfX methods (horizontal) and dedicated layers for each DfX method (vertical) allow creating the suitable ontology for the systematic collection of the DfX rules considering each target. Moreover, the proposed framework is the first step for developing (future work) a software tool to assist engineers and designers during product development (3D CAD modelling).A design for assembly (DfA) case study shows how to collect assembly rules in the given framework. It demonstrates the applicability of the CAD-integrated DfX system in the mechanical design of a jig-crane. Several benefits are recognized: (i) systematic collection of DfA rules for informatics development, (ii) identification of assembly issues in the product development process, and (iii) reduction of effort and time during the design review.  相似文献   
6.
Walter Aprile and Stefano Mirti have been engaged as designers, researchers and teachers at Interaction-Ivrea, a technological research institute in northern Italy, since it was established by Telecom Italia and Olivetti in 2001. Here, the two reflect on the series of experiments they have undertaken at the intersection of interactive technology and architecture, analysing their own working systems and the means by which they have chosen to pursue interdisciplinary dialogue. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
7.
LCBll是三相电流差动保护装置,是由美国西屋公司生产的,最早用于广东大亚湾核电站工程。该站的所有40()k和500kV出线的主1保护均是LCBll。后来沙江乙线的主1也是这种保护。ILCBll电流差动的原理简介LCB11电流差动保护可用于两端和三端网络,依靠高频通道将两(三)侧装置联系起来,保护构成示意图如图1。每侧的三相电流被转换成电压,由序网滤波器将这些电压综合成能代表三相电流信息的单相电压VLD(如图2)。序网包括正序、负序和零序网络,均能被独立调节,以使其输出量能最好地代表系统的情况。序网的输出  相似文献   
8.
McLean's Nuggets     
The development of a clean, plentiful and low-cost alternative energy source is the holy grail of the 21st century. Ken Yeang looks into his crystal ball and asks whether the future could lie in nanoenergy and the proliferation of numerous personal nanogenerators - attached to buildings, individuals or under bridges. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
9.
Spinning Reserve is one of the ancillary services which is essential to satisfy system security constraints when the power system faces with a contingency. In this paper, Day Ahead Demand Response Program as one of the incentive-based Demand Response programs is implemented as a source of spinning reserve. In this regard, certain number of demands are selected according to a sensitivity analysis, and simulated as virtual generation units. The reserve market is cleared for Spinning Reserve allocation considering a probabilistic technique. A comparison is performed between the absence and existence of Day Ahead Demand Response Program from both economical and reliability viewpoints. Numerical studies based on IEEE 57 bus test system is conducted for evaluation of the proposed method.  相似文献   
10.
A new alumina-supported, not pyrophoric Raney-type Ni-catalyst   总被引:2,自引:0,他引:2  
Starting with a 50–50 wt.% Al–Ni alloy powder a new process was developed by which an active alumina supported, not pyrophoric Raney-type Ni catalyst is produced. It consists of very finely dispersed nickel of 25–30 wt.% (specific weight of about 1.2). The Ni is not ferromagnetic. The catalyst is applied in all liquid phase hydrogenations where standard Raney-Ni is used, with the same or higher specific activity.

The structure of the catalyst is described using XRD, SAXS, TEM SEM/EDX, and N2-sorption. The catalytic activity measurements were performed in liquid phase hydrogenations at room temperature and atmospheric pressure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号