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921.
McMinn Mark R.; Ruiz Janeil N.; Marx David; Wright J. Brooke; Gilbert Nicole B. 《Canadian Metallurgical Quarterly》2006,37(3):295
What is a professional psychologist to do when a client brings up the concept of sin? To some, sin may seem like a stifling religious relic that has no place in contemporary psychology. But viewing sin from within the Christian faith, and in tandem with the doctrine of grace, can help psychologists understand why sin is such an important concept for many of their Christian clients. Psychologists' misunderstanding of sin and grace may contribute to relatively low rates of referral from Christian leaders to clinical psychologists, and may sometimes hinder therapeutic progress. Two methods of data collection, involving a total of 171 respondents, were used to discern what Christian leaders wish psychologists understood regarding the doctrine of sin. Respondents emphasized the nature and consequences of sin, grace, and the importance of psychologists understanding sin and grace. Implications for professional psychologists are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
922.
This paper presents a 2-D DCT/IDCT processor chip for high data rate image processing and video coding. It uses a fully pipelined
row–column decomposition method based on two 1-D DCT processors and a transpose buffer based on D-type flip-flops with a double
serial input/output data-flow. The proposed architecture allows the main processing elements and arithmetic units to operate
in parallel at half the frequency of the data input rate. The main characteristics are: high throughput, parallel processing,
reduced internal storage, and maximum efficiency in computational elements. The processor has been implemented using standard
cell design methodology in 0.35 μm CMOS technology. It measures 6.25 mm2 (the core is 3 mm2) and contains a total of 11.7 k gates. The maximum frequency is 300 MHz with a latency of 172 cycles for 2-D DCT and 178
cycles for 2-D IDCT. The computing time of a block is close to 580 ns. It has been designed to meets the demands of IEEE Std.
1,180–1,990 used in different video codecs. The good performance in the computing speed and hardware cost indicate that this
processor is suitable for HDTV applications.
This work was supported by the Spanish Ministry of Science and Technology (TIC2000-1289).
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923.
Mutual effects of porosity and reactivity in char oxidation 总被引:8,自引:0,他引:8
The motivation for this review is the need to understand the interdependence of porous structure and reactivity of highly porous carbonaceous materials during oxidation. These materials can be oxidized in three regimes: regime I, kinetically controlled conditions; regime II, partial diffusion-controlled conditions; regime III, diffusion controlled conditions. Since the emphasis here is on the porous structure and its influence on reactivity, conditions where transport processes are dominant were not included for they mask the view of interest. Therefore, the review discusses only physicochemical processes occurring during oxidation of highly porous chars in regime I. Furthermore, reactivity is influenced by many factors, such as catalysis, volatile matter, and water content. To avoid the effect of these factors, highly porous synthetic chars with nothing but elemental carbon and residual hydrogen and oxygen was chosen. Mainly, we discuss a commercial product known as Spherocarb which consists of spherical particles with specific surface area of about 1000 m2 g−1 and porosity of about 0.6. These particles are well defined and reproducible in their properties. They serve well as model materials for various synthetic chars, coal chars, and other carbonaceous materials. The review presents in a systematic manner macroscopic properties and processes that shed light on different aspects of porosity and reactivity. These are presented both from experimental observation as well as modeling view. An attempt was made to present a porous structure model that can reconstruct all available experimental data on these particles during oxidation. In the review the following processes and properties are discussed: shrinkage, fragmentation, and porosity. All are directly connected to porous structure and reactivity. 相似文献
924.
This study evaluates the performance of 12 models to estimate hourly diffuse solar irradiation on inclined surfaces from those measured on horizontal surfaces. Total solar irradiation incident on a tilted surface consists of three components including: beam, diffuse and reflected from the ground. On a semi-hourly basis, the beam component can be calculated by the ratio of the incidence angle to the solar zenith angle. The reflected component has a small effect on calculations and may be calculated with an isotropic model. In contrast, models for estimating the diffuse component show major differences, which justify the validation study that this paper discusses. Twelve models were tested against recorded south- and west-facing slope irradiances at Karaj (35°55′N; 50°56′E), Iran. The following models were included: Badescu [Ba], Tian et al. [Ti], Perez et al. [P9], Reindl et al. [Re], Koronakis [Kr], Perez et al. [P8], Skartveit and Olseth [SO], Steven and Unsworth [SU], Hay [Ha], Klucher [Kl], Temps and Coulson [TC], and Liu and Jordan [LJ].The relative root mean square error (RMSE), for the south-facing surface ranges from 10.16% to 54.89% for the SO and TC models, respectively. For the west-facing surface, RMSE ranges from 30.71% for the P9 model to 63.53% for the TC model. Statistical indices show that all models produce large errors for the west-facing surface. Statistical indices for the south-facing surface show reasonably good agreement with measured data. 相似文献
925.
Ruiz Marc Boitier Fabien Shariati Behnam Layec Patricia Velasco Luis 《Photonic Network Communications》2020,40(2):68-81
Photonic Network Communications - Low-cost low-margin implementation plays an essential role in upgrading optical metro networks required for future 5G ecosystem. In this regard, low-resolution... 相似文献
926.
Sanjay K. Dhurandher Jagdeep Singh Isaac Woungang Raghav Kumar Geetanshu Gupta 《International Journal of Communication Systems》2020,33(8)
Opportunistic networks (OppNets) are composed of wireless nodes opportunistically communicating with each other. These networks are designed to operate in a challenging environment characterized by high delay, intermittent connectivity, and no guarantee of fixed path between the sender and the destination nodes. One of the most vital issues in designing and maintaining practical networks over a time period is the security of the messages flowing in OppNets. This paper proposes a new method called message trust‐based secure multipath routing protocol (MT‐SMRP) for opportunistic networks. Various routing protocols such as ProPHet, Epidemic, and HiBOp, to name a few, have been proposed for OppNets, but none of these have applied a secure multipath routing technique. The proposed MT‐SMRP scheme relays the message to the destination through the disjoint paths, each applying a soft‐encryption technique to prevent message fabrication attacks. Simulations are conducted using the Haggle Infocom'06 real mobility data traces, showing that when time‐to‐live is varied, (1) the proposed MT‐SMRP scheme outperforms D‐MUST by 18.10%, 7.55%, 3.275%, respectively, in terms of delivery probability, messages dropped, and average latency; (2) it also outperforms SHBPR by 21.30%, 7.44%, and 4.85%, respectively, in terms of delivery probability, messages dropped, and average latency. Under similar performance metrics, the performance of MT‐SMRP is also shown to be better than that of D‐MUST and SHBPR when the buffer size (respondents. the message generation interval) is varied. 相似文献
927.
Gas markets are becoming increasingly important around the world and the long-term evolution of these markets is of strategic importance for many countries. This makes it essential to understand how regulation and intervention in these markets affects the long-term prospect for the secure supply of gas. We use Argentina as a case to illustrate some of the issues and consequences of gas regulation. Argentina is a country that has had a significant increase in the use of gas over the years, and where a potential gas deficit looms large in the present and the future. Based on a simulation model developed to understand the supply of gas in Argentina, we discuss how regulation will influence the long-term supply of gas in both Argentina and surrounding countries. Using the model, we develop a series of scenarios to highlight the consequences of different current and possible future interventions in the market by the Regulator. Finally, we discuss short-term regulatory options to reduce the impact of a gas deficit, and the possibility of securing the long-term supply of gas in Argentina. 相似文献
928.
929.
MicroRNAs expression in normal and malignant colon tissues as biomarkers of colorectal cancer and in response to pomegranate extracts consumption: Critical issues to discern between modulatory effects and potential artefacts 下载免费PDF全文
Antonio González‐Sarrías Patricia Casas‐Agustench Francesco Visioli Tamara Monedero‐Saiz Noelia V. García‐Talavera María B. Gómez‐Sánchez Carmen Sánchez‐Álvarez Ana M. García‐Albert Francisco J. Rodríguez‐Gil Miguel Ruiz‐Marín Francisco A. Pastor‐Quirante Francisco Martínez‐Díaz Francisco A. Tomás‐Barberán María Teresa García‐Conesa Juan Carlos Espín 《Molecular nutrition & food research》2015,59(10):1973-1986