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31.
This paper presents an improved model for global sunshine duration estimation. The methodology incorporates geostationary satellite images by including snow cover information, sun and satellite angles and a trend correction factor for seasons, for the determination of cloud cover index. The effectiveness of the proposed methodology has been tested using Meteosat geostationary satellite images in the visible band with a temporal resolution of 1 h and spatial resolution of 2.5 km×2.5 km, for the Brue Catchment in the southwest of England. Validation results show a significant improvement in the estimation of global sunshine duration by the proposed method as compared to its predecessor (R 2 is improved from 0.68 to 0.83, root mean squared error (RMSE) from 2.37 h/d to 1.19 h/d and the mean biased error (MBE) from 0.21 h/d to 0.08 h/d). Further studies are needed to test this method in other parts of the world with different climate and geographical conditions.  相似文献   
32.
This study examined attitudes toward face-to-face (f2f) and online counseling among 228 Korean college students. In addition, it tested a hypothesized model proposing that general propensities (i.e., self-concealment, openness to experience, and loss of face) would influence counseling-specific expectations (i.e., self-stigma and disclosure expectations), which, in turn, would predict attitudes toward f2f and online counseling. Findings mirrored the results of earlier studies revealing that self-concealment was negatively related to attitudes toward both f2f and online counseling, while openness to experience and disclosure expectations were positively related. However, whereas self-stigma was associated with negative attitudes toward f2f counseling, it was not related to attitudes toward online counseling. In addition, disclosure expectations accounted for f2f attitudes more than online attitudes.  相似文献   
33.
Book reviews     
This study examines Black student and parental perceptions of exclusionary practices of Black school principals. I ask why students and parents viewed two Black principals as contributing to abusive and exclusionary school environments that marginalized Black students. After a two-year ethnographic study, it was revealed that exclusionary behaviors toward Black students—which was viewed as “abuse” by students and parents—was a reproduction of the district's racism, and thus adds new considerations for discussions around the value of racially-like (i.e., all Black) educators and students. Parents perceived these two Black principals as dealing more harshly and rigidly with the Black students and their families; moreover, analysis of the interview data revealed that the principals rejected the cultural and social capital, and proclivities of Black students, and blamed Black students for their lower achievement and unique behaviors. I draw significant attention to the larger contexts of White supremacy and racism as I examine how Black principals negotiate their own roles, how they understand their own treatment of urban Black students, and how they are (knowing or unknowingly) reproducing oppressive practices of White supremacy on Black students in school.  相似文献   
34.
This case focuses on enterprise application integration (EAI) in facilitating integrated electronic Government (e-Government) service delivery in a Welsh local authority. Whilst the development of a heterogeneous information technology (IT) infrastructure in the case organisation caused several integration problems, following a non-EAI approach was regarded as satisfactory by the management. The empirical findings illustrate that although the argument for EAI adoption was initially not seen as cost effective, strategically the decision not to implement EAI caused difficulties in the long term for realising integrated e-Government services.  相似文献   
35.
Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.  相似文献   
36.
In this paper, a novel approach for the design of an indirect adaptive fuzzy output tracking excitation control of power system generators is proposed. The method is developed based on the concept of differentially flat systems through which the nonlinear system can be written in canonical form. The flatness-based adaptive fuzzy control methodology is used to design the excitation control signal of a single machine power system in order to track a reference trajectory for the generator angle. The considered power system can be written in the canonical form and the resulting excitation control signal is shown to be nonlinear. In case of unknown power system parameters due to abnormalities, the nonlinear functions appearing in the control signal are approximated using adaptive fuzzy systems. Simulation results show that the proposed controller can enhance the transient stability of the power system under a three-phase to ground fault occurring near the generator terminals.  相似文献   
37.
This article presents a review of the literature on object permanence with an emphasis on research on children with severe disabilities. Object permanence is the realisation that objects continue to exist in time and place even when they are no longer visible. This understanding is achieved across Stages IV(VI of Piaget’s Sensorimotor Period. Children with intellectual disability, physical disabilities, blindness, and autism develop object permanence in a similar sequence although at a slower rate than children without disabilities. Challenges with regulation make it difficult for children with autism to demonstrate object permanence knowledge in Stage VI tasks. There is ample evidence that children with severe disabilities benefit from direct and systematic instruction of object permanence. Assessment‐based instruction, establishment of visual attention, consideration of the characteristics of the object to be hidden (including the impact on differential attention), repeated naming of the object, individually appropriate prompting procedures, and direct reinforcement have been found to support mastery of object permanence in children with disabilities.  相似文献   
38.
Education is the backbone for the development of society. With the advent of technology, it is becoming necessary and being used for the advancement of society. Technology is being used for education as being used in other important fields of life. Usage of technology for education can play a big part in bringing improvement in education For this purpose, this research aims to explore the usage and effects of technology for education. While using the survey method, a questionnaire was constructed for data collection. The sample of the study consists of graduate and postgraduate students from both ODL and regular universities and the sample size would be of 300 respondents (150 from each type of university) who were selected by using simple random sampling. The present study concluded that technology is widely used by both regular and ODL students. This study further concluded that ODL students are more dependent on technology as compared to regular students.  相似文献   
39.
This paper aims to solve the problem of sliding mode control for an uncertain two-dimensional (2-D) systems with states having time-varying delays. The uncertainties in the system dynamics are constituted of mismatched uncertain parameters and the unknown nonlinear bounded function. The proposed problem utilizes the model transformation approach. By segregating the proper Lyapunov–Krasovskii functional in concert with the improved version of Wirtinger-based summation inequality, sufficient solvability conditions for the existence of linear switching surfaces have been put forward, which ensure the asymptotical stability of the reduced-order equivalent sliding mode dynamics. Then, we solve the controller synthesis problem by extending the recently proposed reaching law to 2-D systems, whose proportional part is appropriately scaled by the factor that does not depend on some constant terms but rather on current switching surface’s value, which in turn ensures the faster convergence and better robustness against uncertainties. Finally, the proposed results have been validated through an implementation to a suitable physical system.  相似文献   
40.
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