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In recent decades India has achieved one of the fastest economic growth rates in the world, yet its progress against both child and adult undernutrition has been sluggish at best. While this Indian variant of the so-called Asian enigma presents many puzzles, one of the puzzles pertains to agriculture’s role. Many researchers and policymakers have high expectations of agriculture’s potential to reduce undernutrition, despite a lack of substantive evidence. In this paper we assess this tenuous evidence base by exploring two key channels by which agricultural production conditions can influence nutritional outomes: a food consumption pathway and a maternal employment–time use pathway. We conclude with an appraisal of some possible entry points for pro-nutrition agricultural policies.  相似文献   
3.
While the realization that AIDS is far more than a health problem has dawned only recently, many development organizations have yet to undertake thorough analyses of what this means for what they do, and how they do it. Even fewer have actually changed their policies and procedures to adjust to these new realities. We know that food and nutrition are fundamentally intertwined with HIV transmission and the impacts of AIDS. Food and nutrition security is fundamentally relevant to all four of the conventional pillars of HIV/AIDS response-prevention, care, treatment, and mitigation-and food aid can be an important weapon in the arsenal. This paper, based on a detailed review of the relevant literature and the findings of a mission to eastern and southern Africa, highlights the implications of the HIV/AIDS pandemic for food aid strategy and programming. By viewing food aid programs through an "HIV/AIDS lens" and in the context of a livelihoods approach, the authors argue that organizations can effectively design interventions that reduce both susceptibility to HIV and vulnerability to AIDS impacts. Though there is little empirical evidence regarding the effectiveness of food aid in responding to HIV/AIDS, the authors argue that this should not constrain action. Using past experience as a guide, organizations can learn by doing, documenting, and continually reassessing their programs using the evolving lens, so as to ensure maximal relevance and impact.  相似文献   
4.
In this mathematical presentation, we examined the significance of Hall current on MHD buoyancy-driven boundary layer flow of a Ti6Al4V-H2O based nanofluid past a vertical surface implanted in a uniform permeable region. The vertical surface is considered to be magnetized and induced magnetic field (IMF) impacts are also considered. The nondimensional flow model is solved with the assistance of the two-term perturbation scheme. Various results are obtained by numerical computation for different significant parameters. These results are presented and analyzed in graphical and tabular form. In the boundary layer domain, the transpiration velocity across the surface tends to diminish the main flow, IMF along the main flow, fluid temperature, and concentration. It is remarkably noted that IMF along the main flow grows for incrementing values of volume fraction coefficient of nanofluid. In the magnetic boundary layer domain, the main flow and IMF along the main flow grow with Hall current. Furthermore, it is seen that for the progressing values of magnetic Prandtl number, the main flow reduces while normal flow and IMF along the main flow is induced in the boundary layer domain.  相似文献   
5.
Axial dispersion coefficients (E) in the liquid phase have been measured by unsteady tracer response methods in a 15 cm internal diameter reciprocating plate bubble column, using air and water in countercurrent and cocurrent flow. The operating variables studied were amplitude (0.6–1.27 cm) and frequency (0–5 Hz) of reciprocation, and the superficial velocities of the liquid and gas phases and the spacing between plates. Three types of plate were studied; conventional Karr-type plates with perforation diameters 1.43 cm, plates with smaller (0.635 cm) perforations, and single-perforation (doughnut) plates with internal diameter 7 cm. Measured values of E ranged from about 1 cm2/s to a maximum of 116 cm2/s. In general, the plates with 0.635 cm perforations gave the smallest values of E while the largest values of E were obtained with the doughnut plates, due to vortex ring shedding. The single liquid phase data for the three types of plate were approximately consistent with the correlation of Stevens and Baird (1990). The gas-liquid flow results were interpreted in terms of several different hydrodynamic effects.  相似文献   
6.
To obtain highly conductive buried layers in InP:Fe, MeV energy Si, S, and Si/ Simplantations are performed at 200°C. The silicon and sulfer implants gave 85 and 100 percent activation, respectively, for a fluence of 8 × 1014 cm−2. The Si/S co-implantation also gave almost 100 percent donor activation for a fluence of 8 × 1014 cm−2 of each species. An improved silicon donor activation is observed in the Si/S co-implanted material compared to the material implanted with silicon alone. The peak carrier concentration achieved for the Si/S co-implant is 2 × 1019 cm3. The lattice damage on the surface side of the profile is effectively removed after rapid thermal annealing. Multiple-energy silicon and sulfur implantations are performed to obtain thick and buried n+ layers needed for microwave devices and also hyper-abrupt profiles needed for varactor diodes.  相似文献   
7.
Barium strontium gadolinium bismuth niobate (Ba0.1Sr0.81Gd0.06Bi2Nb2O9, BSGBN) ceramics were prepared by using the conventional solid-state reaction method. The dielectric permittivity, modulus and impedance spectroscopy studies on BSGBN were investigated in the frequency range, 45 Hz–5 MHz and in the temperature range from room temperature (RT) to 570 °C. The dielectric anomaly with a broad peak was observed at 470 °C. Simultaneous substitution of Ba2+ and Gd3+ increases the transition temperature of SrBi2Nb2O9 (SBN) from 392 to 470 °C. XRD studies in BSGBN revealed an orthorhombic structure with lattice parameters a = 5.4959 Å, b/a = 1.000, c = 25.0954 Å. Impedance and modulus plots were used as tools to analyse the sample behaviour as a function of frequency. Cole-Cole plots showed a non-Debye relaxation. Also, dc and ac conductivity measurements were performed on BSGBN. The electric impedance which describes the dielectric relaxation behaviour is fitted to the Kohlrausch exponential function. Near the phase transition temperature, a stretched exponential parameter β indicating the degree of distribution of the relaxation time has a small value.  相似文献   
8.
Various mechanisms for hardening the Linux kernel (for example, enforcing system call policies, device driver failure recovery, protection against exploitation of bugs in code) are proposed in the literature. The main problem with these mechanisms is that, they require changes in the kernel code leading to the possibility of introducing new bugs and hence increasing the testing time. We propose a message filter model as an extension to object‐oriented wrappers for the Linux kernel, to dynamically provide various filtering capabilities to the kernel. This model works as a comprehensive framework for specifying system call policies, handling device driver faults, protecting the kernel against exploits of bugs in code etc, without modifying the existing kernel code. This considerably reduces the possibility of creating new bugs in the kernel code. We have integrated policies for system call interception and device driver failure handling, into the Linux kernel (2.6.9), using message filter model. Our experiments show that the overhead due to our filter objects is very low, making it a useful mechanism for providing filtering capabilities to the Linux kernel. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
9.
Linux is an open‐source operating system, which has increased in its popularity and size since its birth. Various studies have been conducted in literature on the evolution of the Linux kernel, which have shown that there are considerable maintenance problems arising out of the coupling issues in the Linux kernel and this may hamper the evolution of the kernel in future. We propose an object‐oriented (OO) wrapper‐based approach to Linux kernel to provide OO abstractions to external modules. As the major growth of the size of the Linux kernel is in device drivers, our approach provides substantial benefits in terms of developing the device drivers in C++, although the kernel is in C. Providing reusability and extensibility features to device drivers improves the maintainability of the kernel. The OO wrappers provide several benefits to module developers in terms of understandability, development ease, support for OO modules, etc. The design and implementation of C++ wrappers for Linux kernel and the performance of a device driver re‐engineered in C++ are presented in this paper. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
10.
A systematic study on the influence of Nd3+ substitution on structural,magnetic and electrical properties of cobalt ferrite nanopowders obtained by sol–gel auto-combustion routewas reported.The formation of spinel phasewas confirmed by X-ray diffraction(XRD)data,and percolation limit ofNd3?into the spinel lattice was also observed.Fourier transform infrared spectroscopy(FTIR)bands observed ≈580 and ≈390 cm^(-1 ) support the presence of Fe3+ at A andBsites in the spinel lattice.The variation in microstructure was investigated by scanning electronmicroscopy(SEM),and the average grain size varies from 5.3 to 3.3 lm.The substitution of Nd3+ significantly affects the formation of pores and grain size of cobalt ferrite.Room-temperature saturation magnetization and coercivity decrease from 60 to 30 mA·m2·g-1 and 19.9–17.8 mT,respectively,with Nd3+ substitution increasing.These decreases in magnetic properties are explained based on the presence of non-magnetic nature of Nd3+ concentration and the dilution of super-exchange interaction in the spinel lattice.The room-temperature direct-current electrical resistivity increases with Nd3+ concentration increasing,which is due to the unavailability of Fe2+ at octahedral B sites.  相似文献   
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