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131.
While the importance of information technology in reducing soaring healthcare costs and enhancing service quality is increasingly being recognized, significant challenges remain in how it is implemented. Although there are a few studies investigating key IT issues in healthcare in advanced countries, there are virtually none in developing countries. We bridge this gap by investigating the critical information technology issues in healthcare facilities in Turkey. These issues are developed based on the opinions of senior hospital managers. The top ten issues include privacy, quality, security, and the implementation of electronic medical records. Further analyses provide additional insights into the results. 相似文献
132.
Prashant K. Srivastava 《Water Resources Management》2017,31(10):3161-3176
Soil moisture (SM) plays an important role in the water and energy exchanges that occur in the terrestrial surface. Soil moisture can be retrieved at a larger scale by using the visible and InfraRed (IR) bands as well as through the microwave remote sensing. Because of very high importance of SM for variety of applications, there are now two dedicated microwave satellites in the Earth’s orbit for soil moisture retrieval from space. The first, Soil Moisture and Ocean Salinity (SMOS) satellite has been launched by the European Space Agency in November 2009 and second is Soil Moisture Active and Passive (SMAP) launched by the National Aeronautics and Space Administration (NASA) in January 2015. In this review, brief background of soil moisture retrieval algorithms are presented with different applications in the area of water resources. The first section provides the introduction of the soil moisture, presents several in situ techniques for measurement of soil moisture and soil moisture retrieval algorithms from visible/IR and microwave remote sensing. Section 2 describes the satellite soil moisture applications in water resources. 相似文献
133.
A rubber pressure molding (RPM) technique is developed to prepare fiber reinforced plastic components (FRP) using glass fiber and epoxy resin. The technique is based on the matching die set, where the die is made of hard metal like steel and the punch from flexible rubber like materials. The use of flexible rubber punch helps to intensify and uniformly redistribute pressure (both operating pressure and developed hydrostatic pressure due to the flexible rubber punch) on the surface of the product. A split steel die and rubber punch were designed and fabricated to prepare the FRP components. The same split die was also used to cast the rubber punch. Butyl rubber was used to prepare a rubber punch in this investigation. Burn test, coin test, scanning electron microscopy and mechanical tests like interlaminar fracture toughness, interlaminar shear test, tension test, etc were carried out to know the fiber content, void content, presence of delamination, bonding between fiber and resin, microstructure, and mechanical properties of the composite materials. These properties were also compared with FRP components made by the conventional technique to evaluate its performance in the structural applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1095–1102, 2006 相似文献
134.
Peng Song Chi-Wing Fu Prashant Goswami Jianmin Zheng Niloy J. Mitra Daniel Cohen-Or 《Nexus Network Journal》2014,16(1):109-118
This paper presents the detail of our interactive tool for designing reciprocal frame (RF) structures. In general, our tool addresses the RF design problem with three major steps: (1) it supports the design of RF-tessellation by connecting RF patterns and plane tiling; (2) it delivers interactive preview and exploration of RF designs in 3D space through conformal mapping; and (3) it performs a novel optimization method to arrange the rods in the RF-structures, so that we can ensure rod collinear contacts in the structures. This paper supplements our previous work with implementation details, user interface design and operations, as well as a preliminary study and various new results we devised from the tool. 相似文献
135.
Huiyuan Fan Prashant K. Tarun Dachuan T. Shih Seoung Bum Kim Victoria C.P. Chen Jay M. Rosenberger Dan Bergman 《Expert systems with applications》2011,38(12):14899-14906
This paper presents a statistical analysis on the environmental impact of airport deicing activities at Dallas-Fort Worth (D/FW) International Airport. The focus of this paper is on aircraft deicing, which typically uses a spray of aircraft deicing and anti-icing fluids (ADAF). ADAF has a high concentration of ethylene/propylene/diethylene glycol, which shears off airfoil surfaces during takeoff and drips to the runways during taxiing. A significant portion of the glycol runs off and mixes with the airport’s receiving waters during heavy deicing periods, resulting in bacterial growth that causes an increase in chemical oxygen demand (COD) and a subsequent reduction in dissolved oxygen (DO) in the receiving waters. In this study, statistical methods for data mining were employed to evaluate the impact of airport deicing activities on COD and DO in the receiving waters immediately surrounding D/FW Airport. In particular, decision tree models were developed to determine important explanatory variables for predicting levels of COD and DO in the airport’s waterways. The decision tree modeling and analysis of COD determined north–south wind, glycol usage at a specific deicing pad, and monitoring site to be significant explanatory variables. The impact of glycol usage on DO was apparent as every decision tree at least one group with a median DO below 4.0 mg/l, and these low-DO groups were associated with high glycol usage. These results are crucial to D/FW Airport in their goal to minimize the potential adverse impact of deicing activities on the water quality in waterways proximate to the airport. The advantages of data-driven modeling and analysis are its cost-effectiveness due to its potential to be implemented without making major changes in physical systems, ease of application, and usefulness in making future management decisions. 相似文献
136.
137.
In the present investigation, two types (Type A and Type B) of the double-pass packed bed solar air heater under external recycle are investigated theoretically. In Type A, the porous media is considered in the upper channel, whereas in Type B, the porous media is considered in the lower channel. Iron scraps are used as a packed bed material (porous media) to strengthen the convective heat transfer coefficient for air flowing through the packed bed. The mathematical model for these two air heaters operating under forced convection mode is presented. The results revealed that the thermal and thermo-hydraulic efficiencies of Type A are higher as compared to Type B. In order to validate the models, the theoretical results obtained from the conventional model of Type B are compared with the theoretical results obtained from the previous investigation and showed that good agreement is achieved. 相似文献
138.
The objective of this work was to investigate the effect of surface improvement on human hair fiber (HF) based high-density polyethylene (HDPE) reinforced polymer composites. A universal testing machine was used for the characterization of the mechanical behaviors of different types of HF base reinforced HDPE composites, and studies were conducted for the optimization of male/female fiber percentage (15% HF) in polymer composites. The alkali treatment (AT) and acrylic acid treatment (AAT) of HF reinforced HDPE composites showed a remarkable improvement in tensile strength (upto 15.487MPa and 15.638MPa, respectively), which was significantly changed in comparison to the tensile strength of untreated composites. FTIR and SEM test were used to characterize the fiber surface and HF/HDPE reinforced composites. Water absorption kinetics was investigated for the study of diffusion mechanism and kinetics of composites materials, which would be useful to boost the applications of the composite in different areas. 相似文献
139.
Impurities in Cu2ZnSnS4 (CZTS) can alter the electronic and optical properties, which may reduce photovoltaic device efficiency. Phonon dispersion susceptibility can be used to investigate the effects of foreign dopants on pairing between atoms within lattice. In order to investigate the effect of free holes on the optical phonons and asymmetry in the Raman peaks due to impurities, Sb-, Fe-, and Ag-doped CZTS thin films were prepared and systematically studied. Doping with impurities causes a shift in Raman peak frequency as well as linewidth. An investigation has been made based on the reduced mass of the vibrating CZTS lattice that changes due to dopant addition. For polycrystalline Sb-doped CZTS, the predicted wavenumber shift for Raman ‘A’ mode follows a similar trend as evidenced in experiments and can be explained by the square-root relationship between frequency and the vibrating mass. Raman lineshape for Sb-doped CZTS thin films and nanocrystals becomes wider, asymmetric, and moves toward lower vibrational frequency when laser power density increases. Atomic force microscopy was also performed to examine surface properties. 相似文献
140.
Prashant Dhiman 《国际可持续能源杂志》2014,33(4):811-826
In this paper, the thermal performance of double-pass packed-bed solar air heaters is investigated theoretically. A suitable computer program is developed for the analytical solution of the mathematical model which involves the energy balance equations for the different components of the air heaters. Three different characteristics of the double-pass packed-bed solar air heaters are considered for the analysis. The results obtained from the analytical models are compared with the experimental model data obtained from the previous works and showed that good agreement is achieved. 相似文献