The effect of counter electrodes on the photodegrading performances of azoic dye using TiO2 nanotubes arrays

Journal of Materials Science: Materials in Electronics - The novelty of this work is to fabricate the double-walled (DW) TiO2 nanotube arrays (TNAs) by an anode oxidation method with NH4F-based...     

Effect of terbium doping in bismuth ferrite nanoparticles for the degradation of organic pollutant under sunlight irradiation

Journal of Materials Science: Materials in Electronics - Herein, we have studied the influence of terbium (Tb) doping in bismuth ferrite (BiFeO3/BFO) nanoparticles towards its photocatalytic...     

典型绿色建筑评价体系室内环境指标对比分析

对典型绿色建筑评价体系的室内环境评价指标进行对比分析,包括对LEED、BREEAM和中国绿色建筑评价体系中室内环境部分的指标内容、权重体系、达标要求的对比。通过对比分析发现,室内空气品质、光环境、热湿环境、声环境是室内环境质量的主要组成部分,其中,室内空气品质在LEED体系的室内环境部分占大部分内容和分值比重,而在中国绿建体系和BREEAM体系中,四类组成部分的指标数量和分值的分布则相对均匀。虽然中国绿建体系不具有LEED的分值体系和BREEAM的一级权重体系,但其相对众多的控制项以及对应不同绿建等级的室内环境达标项数要求却独具特色。此外,通过对比分析出了三类指标体系所共同关注的室内环境评价的重要内容。     

Adaptive interaction support in ambient-aware environments based on quality of context information

Ambient-aware environments are technologically augmented with myriad sensors, devices and other emerging services in order to support users. However, users find it complex in interacting with such environments due to the presence of numerous devices and services. In this situation, providing context-aware implicit or automatic interaction support may help reducing the cognitive load of the users and facilitate easy access of the available devices and services. However, due to the imprecision in context information, implicit interactions performed by the environment often leads to mis-automation. The result of such impaired implicitness causes distrust and dissatisfaction to the user. In order to address this issue, we propose a system that considers quality of information to dynamically adjust the level of implicit interaction and allows a system to operate in different modes such as full-automation, action suggestion, simple notification, or null action. We conduct experiment in a smart home scenario in order to elicit users’ acceptance and trust regarding the proposed system. Our experiment shows that dynamic and alternative mode of interaction not only increases the satisfaction of users but also helps to avoid distrust in automated actions carried out by the environment under varying contexts.     

Application of artificial neural network models to linear and nonlinear RF circuit modeling

Typical RF and wireless circuits comprise a large number of linear and nonlinear components. The complexity of the RF portion of a wireless system continues to increase in order to support multiple standards, multiple frequency bands, the need for higher bandwidth, and stringent adjacent channel specifications. The time required to carry out a virtual prototyping of such complex circuits and their trade‐off analysis with the baseband circuitry can be unacceptably long, because both the circuit simulation and optimization procedures can be very time consuming. Typically, one divides the task into those of designing the nonlinear elements or subcircuits that can be accurately analyzed by using RF simulators, and uses circuit level analysis for simulating the circuits at module level. In this article, we will review some approaches to modeling both the linear RF elements as well as nonlinear subcircuits (amplifiers, mixers, VCOs), and will emphasize on the application of the artificial neural networks (ANNs). Furthermore, we will demonstrate the use of the ANN to the design of RF circuits and illustrate their application to wireless types of problems of practical interest. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 231–247, 2001.     

Optimum Production and Characterization of Thermostable Amylolytic Enzymes from B. stearothermophilus GRE1

Optimum production of extracellular, thermostable amylolytic enzymes (α and β‐amylase) by a newly isolated bacterium, Bacillus stearothermophilus, was investigated in a batch bioreactor. Starch and lactose at 1.0% and 3.0% (w/v) respectively were found to be optimum for maximum enzyme production. Optimization of cultural conditions (pH 7.0 and temperature 45°C) resulted in high bacterial specific growth rate (0.64 h^?1), yielding 2.20 gL^?1 biomass, 11.43 UmL^?1 α‐amylase and 10.04 UmL^?1 of β‐amylase. Hydrolysis of native starches from wheat, cassava, corn and potato at 60°C using the crude enzyme showed 60‐80% saccharification with potato starch showing the least and wheat starch showing the greatest hydrolysis. The K_m and V_max values of the crude α‐amylase for starch were 4.78 mg starch/mL and 6.67 mg/mL.min respectively.     

Utility based decision support engine for camera view selection in multimedia surveillance systems

Design and implementation of an effective surveillance system is a challenging task. In practice, a large number of CCTV cameras are installed to prevent illegal and unacceptable activities where a human operator observes different camera views and identifies various alarming cases. But reliance on the human operator for real-time response can be expensive as he may be unable to pay full attention to all camera views at the same time. Moreover, the complexity of a situation may not be easily perceivable by the operator for which he might require additional support in response to an adverse situation. In this paper, we present a Decision Support Engine (DSE) to select and schedule most appropriate camera views that can help the operator to take an informed decision. For this purpose, we devise a utility based approach where the utility value changes based on automatically detected events in different surveillance zones, event co-relation, and operator’s feedback. In addition to the selected camera views, we propose to synthetically embed extra information around the camera views such as event summary and suggested action plan to globally perceive the current situation. The experimental results show the usefulness of the proposed decision support system.     

ESR line broadening in Cr3+/MgO at liquid helium temperatures

Line broadening has been observed at 9 GHz in the ESR absorption spectrum of Cr³⁺ in MgO in the liquid helium temperature range, for a range of Cr³⁺ concentrations from 800 7400 ppm. The broadened linewidths at 4.2 K are about two times larger than those at 77 K and depend on polar angle. The lineshapes are Gaussian, in contrast to the Lorentzian lineshape between 293 and 77 K. The broadening is interpreted by the combined effects of strain, due to the charge misfit of Cr³⁺ and the host cation, and temperature which causes both exchange striction and departure from the cubic symmetry to a lower symmetry. Analysis of the linewidth data gives D=(5.25±0.40)×10^–4 cm^–1 and confirms that the total linewidth, H _t, is given by H _t=H ₀+(2D/g) cos _H where H ₀ is the linewidth independent of concentration, temperature and polar angle, _H.     

Service differentiation in multirate wireless networks with weighted round-robin scheduling and ARQ-based error control

The radio link-level delay statistics in a wireless network using adaptive modulation and coding (AMC), weighted round-robin (WRR) scheduling, and automatic repeat request-based error control is analyzed in this letter. WRR scheduling can be used for service differentiation similar to that achievable by using the generalized processor sharing scheduling discipline. The analytical framework presented in this letter captures physical and radio link-level aspects of a multirate multiuser wireless network (e.g., general fading model, AMC, scheduling, error control) in a unified way. It can be used for admission control and cross-layer design under statistical delay constraints. The analytical results are validated by simulations. Typical numerical results are presented, and their useful implications on the system performance are discussed.     

An analytical approach to providing controllable differentiated quality of service in Web servers

Provisioning quality of service (QoS) in Web servers has gained immense importance because Web servers are a major part of the Internet. To deliver the pledged QoS, Web service providers need control over the allocation of the resources in their Web servers. Control is also necessary for reaching the optimal resource allocation through proper service differentiation. In this paper, we propose and investigate an analytic approach that enables the service providers to deploy a differentiated service policy that offers this control. The proposed service policy is configurable by tunable control parameters. We devise the relationships between the performance measures and these parameters by adopting a unique queuing theoretic approach. Once these relationships are established, we describe how these parameters can be set to their most appropriate values depending on the objectives of the service providers. We illustrate the usefulness of our approach by conducting the analysis on a real Web trace.