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排序方式: 共有346条查询结果,搜索用时 31 毫秒
331.
Mokhtar N Gerardo-Abaya J da-Cruz BM Kim SA Iyengar GV 《Archivos latinoamericanos de nutrición》2004,54(1):9-16
The global nutrition community recognizes the usefulness of nuclear and isotopic techniques and especially stable isotopes for accurate measurements in key areas of human nutrition and health. Although progress has been made in many Latin America countries in reducing the absolute number of undernourished people, food policy and public health communities have to face the double burden on health. On one side they have to address the prevention of obesity and on the other side they are trying to reduce undernutrition. However, to be successful in development of sustainable nutrition programs, a combination of relevant scientific knowledge and approaches that are practical is required to assure even a reasonable level of success. The objectives of this review are to highlight the role of isotopic techniques in nutritional studies and to review the role of the International Atomic Energy Agency in supporting nutrition interventions in Latin America countries. 相似文献
332.
The performance characteristics of hydrodynamically lubricated journal bearings are dealt with in this paper, thermal aspects are considered and axial groove and spiral oil inlet feeding conditions are assumed.A finite journal bearing was assumed and, by the aid of numerical solutions, the Reynolds equation coupled with the energy equation in finite difference form could be solved to give an adiabatic solution. A specially devised computer program has been adopted to compute the hydrodynamic pressure and temperature distributions and to predict the performance characteristics under isothermal and thermal conditions.The results indicated that axial oil feeding allows a higher load-carrying capacity at a lower frictional resistance compared with the spiral oil inlet. 相似文献
333.
H Herikstad P Hayes M Mokhtar ML Fracaro EJ Threlfall FJ Angulo 《Canadian Metallurgical Quarterly》1997,3(3):371-372
We conducted a national survey of antimicrobial resistance in human clinical isolates of Salmonella between July 1, 1994, and June 30, 1995. Every tenth nontyphoidal Salmonella isolate received at state public health laboratories in the United States during this period was tested for resistance to 12 antimicrobial agents, including two quinolones, nalidixic acid, and ciprofloxacin. Emerging quinolone resistance was detected; of 4,008 isolates tested, 21 (0.5%) were resistant to nalidixic acid, and one (0.02%) was resistant to ciprofloxacin. Continued surveillance for quinolone-resistant Salmonella is necessary, particularly after the recent approval of a fluoroquinolone for use in animals intended for food in the United States. 相似文献
334.
A one-year prospective study comparing Section 136 patients (39) and the severe Section 2 or 4 patients (29) of the Mental Health Act 1983 in a hospital with inner London catchment areas. The assessments were clinical, nurses' ratings and socio-demographic. The results showed that clinical and nursing ratings did not differentiate the two groups. Most social/demographic data showed similar trends with both groups being disadvantaged but Section 136 patients slightly more so. The differences were smaller than anticipated, suggesting a recent shift of patients admitted under Section 2 or 4 towards a more socially disadvantaged position. In conclusion, police did not overuse Section 136. Our comparison suggests: (a) police may underuse Section 136, and (b) Section 136 acts as a valuable 'back-up' for those patients who would otherwise fail to benefit from the Mental Health Act. 相似文献
335.
Computerized Layout Design: A Branch and Bound Approach 总被引:3,自引:1,他引:2
Mokhtar S. Bazaraa 《IIE Transactions》1975,7(4):432-438
This paper presents a computerized procedure for layout design. The layout problem is formulated as a quadratic set covering problem. A branch and bound method for optimizing the resulting problem is devised. As a result, optimal and suboptimal layouts can be provided to the layout engineer for consideration and modification. 相似文献
336.
Sonia Ben Mokhtar Nikolaos Georgantas Valrie Issarny 《Journal of Systems and Software》2007,80(12):1941-1955
Pervasive computing environments are populated with networked services, i.e., autonomous software entities, providing a number of functionalities. One of the most challenging objectives to be achieved within these environments is to assist users in realizing tasks that integrate on the fly functionalities of the networked services opportunely according to the current pervasive environment. Towards this purpose, we present COCOA, a solution for COnversation-based service COmposition in pervAsive computing environments with QoS support. COCOA provides COCOA-L, an OWL-S based language for the semantic, QoS-aware specification of services and tasks, which further allows the specification of services and tasks conversations. Moreover, COCOA provides two mechanisms: COCOA-SD for the QoS-aware semantic service discovery and COCOA-CI for the QoS-aware integration of service conversations towards the realization of the user task’s conversation. The distinctive feature of COCOA is the ability of integrating on the fly the conversations of networked services to realize the conversation of the user task, by further meeting the QoS requirements of user tasks. Thereby, COCOA allows the dynamic realization of user tasks according to the specifics of the pervasive computing environment in terms of available services and by enforcing valid service consumption. 相似文献
337.
Automatic motion detection features are able to enhance surveillance efficiency and quality. The aim of this research is to
recognize and detect motion automatically around a robot's environment in order to equip a mobile robot for a surveillance
task. The required information is based on the input obtained from a charge coupled device (CCD) camera mounted on the mobile
robot. As the first step toward achieving the goal, it is necessary to have a stationary mobile robot and moving objects.
Experiments in a different environment, such as different movements, size of moving objects, and lighting conditions, have
also been conducted. The “adjacent pixels comparison” is the proposed method to detect motion in this experiment. The results
have verified that the motion detection experiments operate as expected.
This work was presented in part at the 11th International Symposium on Artificial Life and Robotics, Oita, Japan, January 23–25, 2006 相似文献
338.
Ahmed S. Salama Mohamed Amr Mokhtar Mazhar B. Tayel Esraa Eldesouky Ahmed Ali 《计算机、材料和连续体(英文)》2021,68(1):431-446
Assuring medical images protection and robustness is a compulsory necessity nowadays. In this paper, a novel technique is proposed that fuses the wavelet-induced multi-resolution decomposition of the Discrete Wavelet Transform (DWT) with the energy compaction of the Discrete Wavelet Transform (DCT). The multi-level Encryption-based Hybrid Fusion Technique (EbhFT) aims to achieve great advances in terms of imperceptibility and security of medical images. A DWT disintegrated sub-band of a cover image is reformed simultaneously using the DCT transform. Afterwards, a 64-bit hex key is employed to encrypt the host image as well as participate in the second key creation process to encode the watermark. Lastly, a PN-sequence key is formed along with a supplementary key in the third layer of the EbHFT. Thus, the watermarked image is generated by enclosing both keys into DWT and DCT coefficients. The fusions ability of the proposed EbHFT technique makes the best use of the distinct privileges of using both DWT and DCT methods. In order to validate the proposed technique, a standard dataset of medical images is used. Simulation results show higher performance of the visual quality (i.e., 57.65) for the watermarked forms of all types of medical images. In addition, EbHFT robustness outperforms an existing scheme tested for the same dataset in terms of Normalized Correlation (NC). Finally, extra protection for digital images from against illegal replicating and unapproved tampering using the proposed technique. 相似文献
339.
The aim of this article is to conduct the lattice Boltzmann simulation of the magnetohydrodynamic (MHD) natural conjugate heat transfer in an apportioned cavity loaded with a multiwalled carbon nanotube/water nanofluid. The divided cavity is, to some extent, heated and cooled at the upright walls, whereas the horizontal walls are adiabatic. The nanofluid properties are evaluated on the basis of experimental correlations. The parameters ranges in the study are as follows: nanoparticles' volume fraction (%): 0 ≤ ? ≤ 0.5, temperature (°C): T = 27, Rayleigh number (Ra): 103 ≤ Ra ≤ 105, Hartmann number (Ha): 0 ≤ Ha ≤ 90, and the magnetic field inclination angle (γ): 0 ≤ γ ≤ π/2. The current outcomes are observed to be in great concurrence with the numerical results introduced in the literature. The impacts of the aforesaid parameters on local and average heat transfer, entropy generation, and Bejan number (Be) are explored and discussed. Indeed, the transfer of heat increases linearly with ? for a low Ra. As Ra increases, the average Nusselt number decreases for a high value of ?. The increase of nanoparticles' volume fraction leads to a reduction in the entropy generation and an increase in the Bejan number for a high Ra, but at low Ra, these functions remain constant. As the Ha increases, the transfer of heat and the entropy generation decreases, whereas there is an increase in Be. The transfer of heat, total entropy generation, and the Be depends strongly on the direction of the magnetic field. The increase of heater and cooler size has a great influence on the transfer of heat, entropy generation, and Be. 相似文献
340.
Chemical composition and nutritive value of lantana and sweet pepper seeds and nabak seed kernels 总被引:1,自引:0,他引:1
Abstract: Chemical analysis was carried out on lantana (Lantana camara) and sweet pepper (Capsicum annuum L.) seeds and nabak (Zizyphus spina‐christi) seed kernels. The proximate analysis (on dry weight basis) of sweet pepper seeds, lantana seeds, and nabak seed kernels showed the following composition: moisture 70.95%, 17.27%, and 4.22%; ash 4.88%, 1.81%, and 3.51%; fat 19.57%, 11.0%, and 30.19%; crude protein 19.28%, 6.3%, and 38.2%; and carbohydrate 56.3%, 80.9%, and 28.1%, respectively. For minerals, potassium was the most abundant element, followed by phosphorus and sodium. Also, zinc, iron, copper, and manganese were detected. Analysis of amino acids revealed that the first limiting amino acid was valine, for both lantana and sweet pepper seeds, but it was threonine for nabak seed kernels. Antinutritional compounds, including, phytic acid, trypsin inhibitor, and tannins, were detected in all seeds. Results of fatty acid compositions showed that the major fatty acid was oleic acid in both lantana (48.73%) and nabak oils (53.25%), but it was linoleic acid in sweet pepper oil (71.55%). Moreover, the degree of unsaturation of these oils was close to that of common vegetable oils. In all oils, there was absorbance in the ultraviolet (UV)‐B and UV‐C ranges with potential for use as broad spectrum UV protectants. It can be inferred that the seeds investigated are good sources of crude fat, crude protein, ash, carbohydrate, and some minerals. Furthermore, the oil extracts could be useful as edible oils and for industrial applications. Practical Application: The nutritional composition of the investigated seeds suggested that they could be used to meet part of the nutritional requirements of animal feeds. Also, they could be regarded as good sources of food ingredients and as new sources of edible oils. 相似文献