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1.
Abstract.  While a large body of research exists on the development and implementation of software, organizations are increasingly acquiring enterprise software packages [e.g. enterprise resource planning (ERP) systems] instead of custom developing their own software applications. To be competitive in the marketplace, software package development firms must manage the three-pronged trade-off between cost, quality and functionality. Surprisingly, prior research has made little attempt to investigate the characteristics of packaged software that influence management information system (MIS) managers' likelihood of recommending purchase. As a result, both the criteria by which MIS managers evaluate prospective packaged systems and the attributes that lead to commercially competitive ERP software products are poorly understood. This paper examines this understudied issue through a conjoint study. We focus on ERP systems, which are among the largest and most complex packaged systems that are purchased by organizations. In a conjoint study, 1008 evaluation decisions based on hypothetical ERP software package profiles were completed by managers in 126 organizations. The study represents the first empirical investigation of the relative importance that managers ascribe to various factors that are believed to be important in evaluating packaged software. The results provide important insights for both organizations that acquire such systems and those that develop them. The results show that functionality, reliability, cost, ease of use and ease of customization are judged to be important criteria, while ease of implementation and vendor reputation were not found to be significant. Functionality and reliability were found to be the most heavily weighted factors. We conclude the paper with a detailed discussion of the results and their implications for software acquisition and development practice.  相似文献   
2.
Abstract. In an increasingly dynamic business environment characterized by fast cycle times, shifting markets and unstable technology, a business organization’s survival hinges on its ability to align IT capabilities with business goals. To facilitate the successful introduction of new IT applications, issues of project risk must be addressed, and the expectations of multiple stakeholders must be managed appropriately. To the extent that users and developers may harbour different perceptions regarding project risk, areas of conflict may arise. By understanding the differences in how users and project managers perceive the risks, insights can be gained that may help to ensure the successful delivery of systems. Prior research has focused on the project manager’s perspective of IT project risk. This paper explores the issue of IT project risk from the user perspective and compares it with risk perceptions of project managers. A Delphi study reveals that these two stakeholder groups have different perceptions of risk factors. Through comparison with a previous study on project manager risk perceptions, zones of concordance and discordance that must be reconciled are identified.  相似文献   
3.
Stochastic models for hardware-software systems are developed and used to study their performance as a function of hardware-software failure and maintenance rates. Expressions are derived for the distribution of time to a specified number of software errors, system occupancy probabilities, system reliability, availability, and average availability. The behavior of these measures is investigated via numerical examples.  相似文献   
4.
By measuring the temperature jump in the presence of a heat flux across niobium disks surrounded by He II, we determined the Kapitza resistance, R k, for different surface roughness and bulk purity. The experiments were conducted from 1.5 K to T , under saturated vapour pressure. The influence of foreign atoms due to the presence of Ti near the interface was also investigated. The importance of R k on the efficiency of superconducting cavities is discussed.  相似文献   
5.
Urinary isolates of Proteus mirabilis, obtained from 49 RA patients and 44 healthy controls, were tested for susceptibility to antibiotics by the disc diffusion method. In addition, P. mirabilis isolates were also tested for proticine production and sensitivity (p/s) typing by the inhibition of growth of each test isolate against 13 reference strains of P. mirabilis. The P. mirabilis isolates from both RA patients and healthy controls were highly susceptible to norfloxacin, ciprofloxacin and trimethoprim, but less to minocycline. The urine of RA patients contained fewer different types of P. mirabilis strains than those isolated from healthy controls. All of the strains found in the RA patients were proticine producers (P < 0.001), mostly of proticine 3 (P < 0.005). The presence of such strains provides evidence of a sub-clinical upper urinary tract infection with P. mirabilis in some RA patients. Therapeutic intervention in RA with relevant antibiotics requires evaluation.  相似文献   
6.
Experimental data available on roton contribution to the growth resistance of helium-4 surfaces from the work of Amrit, Legros and Poitrenaud (ref. 4) are analysed using the quantum kind model of Edwards, Mukherjee and Pettersen (ref. 5). The results are in strong favour of dissipation being due to kink-roton interactions. Further, they also support the idea that the angular anisotropy of the roton growth resistance of rough crystral surfaces is related to the density of steps.  相似文献   
7.
This paper presents a stochastic model for the software failure phenomenon based on a nonhomogeneous Poisson process (NHPP). The failure process is analyzed to develop a suitable meanvalue function for the NHPP; expressions are given for several performance measures. Actual software failure data are analyzed and compared with a previous analysis.  相似文献   
8.
Larval fish were sampled in Long Point Bay each summer in 1971–78 by towing ½– and 1-m diameter plankton nets at about 1 m/s. We report on the analysis of 2,576 tows, giving detailed consideration to sampling problems and statistical methods. The most common larvae were rainbow smelt (Osmerus mordax), caught in about 50% of the tows, and yellow perch (perca flavescens), clupeids, and cyprinids, caught in about 10 to 20% of the tows. Most of the data contained too high proportions of zero catches to be transformed to approximately normal distribution, and were therefore analyzed using the log-linear model rather than by analysis of variance. Except for cyprinids, larval fish seemed to be scarce in surface waters during the day. Small (4 to 10 mm long) smelt and perch larvae were caught more frequently in 526– than in 782–μm mesh nets. Very few perch and cyprinid larvae longer than 10 mm were ever caught. This, and a more rapid decline of daytime than nighttime catches of larval smelt through the mid-summer, suggests that the nets were avoided by at least the larger larvae. If avoidance of sampling gear is substantial, larval fish abundances may be overestimated in years of slow growth when the larvae remain catchable longer. We saw no evidence that the recent industrial development at Nanticoke, Ontario, has affected larval fish abundances so far. As the annual mean densities of larval fish varied 15-fold or more, it would require several years of observation to detect any but drastic future change from the current levels of abundance.  相似文献   
9.
A pulse tube cryocooler (PTC) for future metrological satellites has been developed at one of the lead centers of the Indian Space Research Organisation in Bangalore, India for cooling on-board Infrared (IR) detectors to 80 K.A study has been conducted on the coldfinger of PTC to understand the off-state heat loads on the cooler by varying the value of gravity numerically in ANSYS FLUENT and experimentally by orienting the setup with respect to gravity. The off-state parasitic losses represent a major heat load in on-board applications that include redundant, viz. nonoperating coolers. To find out the amount of off-state parasitic heat losses in a nonoperating coldfinger of the PTC experimentally, transient warm-up technique was used. Various heat loads were applied experimentally on the cryo-tip at temperatures ranging from 80 to 100 K for determining the parasitic losses. The effect of orientation of PTC on the off-state parasitic heat load with respect to gravity is studied and presented in this paper. Enhancement due to free convection heat flow normalized by gas molecular conduction in pulse tube is analyzed using computational fluid dynamics to verify and compare with experimental results. The best orientation angle where the parasitic is low is when the cold end of the coldfinger of pulse tube cryocooler faces down (0°) and high when the cold end of the coldfinger is oriented to 135°.  相似文献   
10.
Journal of Failure Analysis and Prevention - This study involves the failure analysis of carbon steel tubes in a reformed gas boiler feed water preheater unit operating at an ammonia plant. It was...  相似文献   
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