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1.
Based on the Euler-Maclaurin formula in the spirit of [1], we provide a unified approach to some inequalities of Ostrowski-Grüss type, which include some existing results as special cases. Some illustrative examples are also included.  相似文献   
2.
《Polymer Contents》2005,22(4):221-222
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4.
The incorporation of social issues in software engineering is limited. Still, during the last 20 years the social element inherent in software development has been addressed in a number of publications that identified a lack of common concepts, models, and theories for discussing software development from this point of view. It has been suggested that we need to take interpretative and constructive views more seriously if we are to incorporate the social element in software engineering. Up till now we have lacked papers presenting ‘simple’ models explaining why. This article presents a model that helps us better to understand interpretation, interaction and reality construction from a natural language perspective. The concepts and categories following with the model provide a new frame of reference useful in software engineering research, teaching, and methods development.  相似文献   
5.
DNA was extracted from commercial rice cereal products using modified conventional methods (CTAB, SDS and a commercial kit) in large fragments (>3 kb) and with relatively high yields (1.4–10.7 μg DNA per g of sample) and was used as template for the amplification of a single copy rice gene (i.e. MIPS) fragment (ca. 850 bp) and microsatellite DNAs (ca. 120–400 bp). The cereal products were further discriminated by using six microsatellite markers. The usefulness of DNA analysis was discussed for quality control and authenticity testing of raw rice materials in rice-based food production, and to monitor genetically modified (GM) rice ingredients in commercial food products.  相似文献   
6.
The primary objective of this paper is to develop a simulation model for the fluid–structure interactions (FSI) that occur in pipeline systems mainly due to transient events such as rapid valve closing. The mathematical formulation is based on waterhammer equations, traditionally used in the literature, coupled with a standard beam formulation for the structure. A new finite element formulation, based on flow velocity, has been developed to deal with the valve closure transient excitation problems. It is shown that depending on the relative time-scales associated with the structure, fluid and excitation forces, there are situations where the structural vibration response increases with FSIs. This is in contrast to what is normally accepted in the literature, i.e. FSI reduces the structural displacements.  相似文献   
7.
《Microelectronic Engineering》2007,84(9-10):2251-2254
In this work we present an evaluation and understanding of corona charge measurements on decoupled plasma nitrided (DPN) HfSiOx. Typical corona charge parameters such as equivalent oxide thickness (EOT), density of interface states (Dit) and saturated surface voltage (Vsat) are evaluated. It is shown that especially Dit and Vsat are promising parameters for nitiridation monitoring as they show correlation to DPN parameters within good accuracy. Fundamental explanation is given for the observed behaviour of Vsat by use of a direct tunneling model.  相似文献   
8.
设计了一款造价低,体积小,操作简单,适用性广的抢答器。该抢答器是基于MAX+PLUSII软件,在FPGA芯片上设计的,可实现多人智力竞赛抢答。  相似文献   
9.
In the presence of rate constraints in actuator, design of cascade controller based on the primary controller conditional integration can result into closed-loop system oscillations. Stability analysis, performed by the describing function technique and confirmed by simulation, demonstrates that the solution based on the Anti-Reset Windup Cascade Control System (ARW CCS) structure is successful. Design and tuning of the ARW CCS secondary controller is a standard ARW single-input single-output problem. In the present paper tuning is proposed for the ARW CCS primary controller. For the serial process modeling simple rules are derived and confirmed by experimental results, obtained on a drum type boiler of a 210 MWe lignite coal fired unit. General design of the ARW CCS is based on the parallel process modeling and optimization of the primary controller. Optimization is performed in the frequency domain, under constraints on the maximum sensitivity, multiplicative uncertainty bound and sensitivity to measurement noise. Simulation and experimental results on a laboratory thermal plant demonstrate effectiveness of the proposed optimization.  相似文献   
10.
A novel double suction shaft-less mini pump was developed for heat control of small energy systems in this study.The mini pump impeller with an exit diameter of 40 mm was combined with the motor rotor supported by the hybrid dynamic bearing.The specific speed of the pump was 125 min-1 m3 min-1 m.The hydraulic performance of the pump was investigated experimen-tally under four rotational speeds.From the test results,it was recognized that the pump could provide a flow discharge of 5 L/min and head of 1.5 m,w...  相似文献   
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