全文获取类型
收费全文 | 88篇 |
免费 | 7篇 |
专业分类
电工技术 | 2篇 |
综合类 | 1篇 |
化学工业 | 18篇 |
金属工艺 | 1篇 |
机械仪表 | 3篇 |
建筑科学 | 7篇 |
能源动力 | 2篇 |
轻工业 | 5篇 |
无线电 | 12篇 |
一般工业技术 | 29篇 |
冶金工业 | 3篇 |
原子能技术 | 2篇 |
自动化技术 | 10篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 2篇 |
2016年 | 6篇 |
2015年 | 2篇 |
2014年 | 7篇 |
2013年 | 16篇 |
2012年 | 6篇 |
2011年 | 7篇 |
2010年 | 6篇 |
2009年 | 1篇 |
2008年 | 2篇 |
2007年 | 2篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1980年 | 1篇 |
排序方式: 共有95条查询结果,搜索用时 15 毫秒
1.
Wireless Networks - Though Mobile Cloud Computing (MCC) and Mobile Edge Computing (MEC) technologies have brought more convenience to mobile services over past few years, but security concerns like... 相似文献
2.
A. Abrizah Mohammadamin Erfanmanesh Vala Ali Rohani Mike Thelwall Jonathan M. Levitt Fereshteh Didegah 《Scientometrics》2014,101(1):569-585
This paper analyses the information science research field of informetrics to identify publication strategies that have been important for its successful researchers. The study uses a micro-analysis of informetrics researchers from 5,417 informetrics papers published in 7 core informetrics journals during 1948–2012. The most productive informetrics researchers were analysed in terms of productivity, citation impact, and co-authorship. The 30 most productive informetrics researchers of all time span several generations and seem to be usually the primary authors of their research, highly collaborative, affiliated with one institution at a time, and often affiliated with a few core European centres. Their research usually has a high total citation impact but not the highest citation impact per paper. Perhaps surprisingly, the US does not seem to be good at producing highly productive researchers but is successful at producing high impact researchers. Although there are exceptions to all of the patterns found, researchers wishing to have the best chance of being part of the next generation of highly productive informetricians may wish to emulate some of these characteristics. 相似文献
3.
In traditional approach, failure mode and effects analysis determines the risk priories of failure modes through the risk priority number which is determined by multiplication of three risk factors namely, failure occurrence (O), failure severity (S) and failure detection ability (D). In this approach, different weights of risk factors were not taken into consideration so that the three risk factors were assumed to have the same weight. This may not be realistic in real applications. In this paper we treat the risk factors as fuzzy variables and evaluate them using fuzzy linguistic terms and fuzzy ratings. As a result, fuzzy risk priority numbers (FRPNs) are proposed for prioritization of failure modes. The FRPNs are defined as fuzzy geometric means of the fuzzy ratings for O, S and D and can be computed using alpha-level sets and linear programming models. A numerical example is provided to examine the results of this model. 相似文献
4.
Viscous fingering of reactive miscible flow displacements in a homogeneous porous media is examined. A general model where the two reactants and the chemical product have different viscosities is adopted. The problem is formulated using the continuity equation, Darcy's law, and volume-averaged forms of convection–diffusion–reaction equations for mass balance, and is solved using a pseudo-spectral method. A parametric study was performed to examine the effect of the Peclet number and the log-mobility ratios between the chemical product and the reactants. It is shown that the development and growth of the instability as well as the efficiency of the reaction expressed in terms of the amount of chemical product can be predicted based on the mobility ratio at the initial front between the two reactants and effective mobility ratios between the chemical product and either one of the two reactants. Furthermore, it is reported that larger Peclet numbers lead to slower rates of chemical production. 相似文献
5.
H. R. Shahverdi M. R. Ghomashchi S. Shabestari J. Hejazi 《Journal of Materials Science》2002,37(5):1061-1066
6.
The calculation of the compliance matrix of foundations is an essential first step in the static or dynamic analysis of soil-foundation interaction problems. An effective numerical method is presented for accurate computation of the static compliance of rigid foundations with arbitrary shapes, which rest on an elastic half-space and are subjected to vertical and horizontal loads, as well as tilting and torsional moments. In this method the contacting area is subdivided into a finite number of ‘equivalent’ circular elements, which leads to solutions in a rather simple form that require minimal numerical computations. The results are illustrated by calculating the overall compliances of foundations of various geometries, and these are compared with results obtained by means of another, more elaborate, method. 相似文献
7.
Scientometrics - This paper reports on book impact assessment using bibliometrics, usage metrics and altmetrics. The objective of the study is to investigate the citation, usage, reach and... 相似文献
8.
Response surface modeling is a well-grounded method to identify empirical relationships between factors involved in engineering experiments. This paper presents a novel mathematical/statistical approach to design an optimal predictive model to evaluate hardness by eddy current method. A new approach has been presented to find an optimal frequency in eddy current testing which maximizes detectability and accuracy of the measured values. In order to determine the hardness values of AISI D2 tool steel during tempering, the eddy current tests were conducted by applying different values of operating frequency in the range 50–1000 Hz. Unknown heat treatment conditions estimated from eddy current tests creates a link that provides hardness estimation. The results showed that coupling the eddy current method to the proposed model acts as a high accurate hardness measuring system for the samples with unknown heat treatment conditions. 相似文献
9.
F. Hejazi M. Dalili Shoaei A. Tousi M. S. Jaafar 《Computer-Aided Civil and Infrastructure Engineering》2016,31(5):381-399
By now, many civil engineering researchers have extensively studied the application of earthquake energy dissipation systems in seismic‐resistant buildings. Earthquake energy dissipation systems play an important role in enhancing the sustainability of structures against seismic excitation. Frame buildings are strengthened by installing damper devices as supplemental structural members. This article presents the finite‐element‐based development of an analytical model for a viscous wall damper (VWD) device, an alternative to other earthquake energy dissipation systems, which can diminish the effect of earthquakes on structures and improve the seismic performance of multistory buildings subjected to ground motion. The constitutive law of VWDs has been formulated and integrated to develop a finite element model of VWD compatible with the reinforced concrete (RC) structure analytical model. Then, the finite element algorithm has been developed for inelastic analysis of RC buildings equipped with VWD devices capable of detecting damage to both structural members and damper connections under dynamic loading. Based on the developed system, the special finite element program was codified and verified by applying it to a real model of a RC building with supplementary VWD devices. Influence of VWDs on seismic performance of the RC building during earthquake excitation was evaluated. The proposed analytical model for VWD is verified by using experimental test data and analysis result proved that this energy dissipation system succeeds by substantially diminishing and dissipating a structure's induced seismic responses. Also the parametric study indicated that the damping coefficient is very effective on performance of VWD. 相似文献
10.
Sayyed Mahdi Hejazi Mohammad Sheikhzadeh Sayyed Mahdi Abtahi Ali Zadhoush 《Iranian Polymer Journal》2013,22(1):15-24
A soft material is defined as a substance that its mechanical properties depend on ambient conditions, e.g. external stresses, temperature, etc. Since composite structures with soft-material matrix do not have adequate pullout resistance with flat-type reinforcements such as fibers, there are a large number of cases where reinforcements with passive resistance are used in conjunction with ordinary fibers. Randomly distributed loop-formed fiber (RDLFF) is a novel idea to reinforce these types of composite materials. Therefore, the main aim of this paper is to use polyethylene RDLFF elements in soft-matrix composites. First, shear behavior of polyethylene RDLFF-reinforced composite was modeled with the use of force-equilibrium method, and then it was compared with that of flat-polyethylene fiber. In the next step, a set of laboratory direct shear tests was conducted on different samples including the neat treatment, polyethylene RDLFF and polyethylene fiber-reinforced composites. Thus, it was shown that through the shearing, a loop-formed fiber has two reinforcing effects including the “fiber effect” and the “loop effect”. The “loop effect” is the main advantage of using RDLFF to ordinary fibers at the same orientation and it is also the major difference in using the two kinds of fibers. The proposed model also indicated that the number of looped-form fibers, fiber diameter, coefficient of friction between fiber and matrix, loop dimension, tensile modulus of fiber, shearing zone and vertical compressive stress determine the shear resistance of RDLFF-reinforced composite. Therefore, the proposed model adequately predicts the shear behavior of soft-matrix composites reinforced with fibers and/or loop-formed fibers. 相似文献