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1.
An approximate method is presented for predicting the effect of a louvered blind on the centre‐glass thermal performance of a fenestration. The method combines a one‐dimensional heat transfer model with data from a numerical simulation of the window and blind. Sample results for a blind mounted on the indoor surface of a window show the effect of blind slat angle on heat transmission. Both summer and winter conditions are considered. The results show that a louvered blind can improve the U‐value of a standard double‐glazed window by up to 37%. Also, the radiation heat exchange with the room can be dramatically reduced (by up to 60%), which will improve the level of occupant comfort. However, there was found to be a trade‐off between U‐value and occupant comfort; placing the blind closer to the window improves the U‐value, but increases the radiation heat exchange with the room. The predictions from the present simplified method compare well with results from a full two‐dimensional computational fluid dynamics solution of the conjugate blind/window interaction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
2.
Multimedia Tools and Applications - Various technologies have been utilized today for recognizing client or user in the indoor areas. These technologies incorporate RSSI, Bluetooth Low Energy... 相似文献
3.
Muhammad Waseem Rizwan Ahmed Muhammad Irfan Shahid Qamar 《Quantum Information Processing》2013,12(12):3649-3664
We present a scheme for the implementation of three-qubit Grover’s algorithm using four-level superconducting quantum interference devices (SQUIDs) coupled to a superconducting resonator. The scheme is based on resonant, off-resonant interaction of the cavity field with SQUIDs and application of classical microwave pulses. We show that adjustment of SQUID level spacings during the gate operations, adiabatic passage, and second-order detuning are not required that leads to faster implementation. We also show that the marked state can be searched with high fidelity even in the presence of unwanted off-resonant interactions, level decay, and cavity dissipation. 相似文献
4.
Muhammad Rashid Zafar Abbas M. Yaseen Qadeer Afzal Asif Mahmood Shahid M. Ramay 《Journal of Superconductivity and Novel Magnetism》2017,30(11):3129-3136
The full potential linearized augmented plane wave method of density functional theory has been used to investigate the structural, electronic, magnetic and thermoelectric properties of cubic perovskites BaVO3 and LaVO3. The ferromagnetic ground state has been found to be stable by comparing the total energies of non-spin-polarized and spin-polarized calculations performed for optimized unit cells. For both compounds, the bond length and tolerance factor are also measured. From the band structures and density of states plots, it is found that both compounds are half-metallic. We found that the presence of V at the octahedral site of these perovskites develops exchange splitting through p-d hybridization, which results in a stable ferromagnetic state. The observed exchange splitting is further clarified from the magnetic moment, charge and spin of the anion and cations. Finally, we also presented the calculated thermoelectric properties of these materials, which show that half-metallic BaVO3 and LaVO3 materials are potential contenders for thermoelectric applications. 相似文献
5.
Berg Alexander Caroff Philippe Shahid Naeem Lockrey Mark N. Yuan Xiaoming Borgström Magnus T. Tan Hark Hoe Jagadish Chennupati 《Nano Research》2017,10(2):672-682
Ternary Ⅲ-Ⅴ nanowires (NWs) cover a wide range of wavelengths in the solar spectrum and would greatly benefit from being synthesized as position-controlled arrays for improved vertical yield,reprodudbility,and tunable optical absorption.Here,we report on successful selective-area epitaxy of metal-particle-free vertical InxGa1-xP NW arrays using metal-organic vapor phase epitaxy and detail their optical properties.A systematic growth study establishes the range of suitable growth parameters to obtain uniform NW growth over a large array.The optical properties of the NWs were characterized by room-temperature cathodoluminescence spectroscopy.Tunability of the emission wavelength from 870 nm to approximately 800 nm was achieved.Transmission electron microscopy and energy dispersive X-ray measurements performed on crosssection samples revealed a pure wurtzite crystal structure with very few stacking faults and a slight composition gradient along the NW growth axis. 相似文献
6.
This article proposes several two-timescale simulation-based actor-critic algorithms for solution of infinite horizon Markov
Decision Processes with finite state-space under the average cost criterion. Two of the algorithms are for the compact (non-discrete)
action setting while the rest are for finite-action spaces. On the slower timescale, all the algorithms perform a gradient
search over corresponding policy spaces using two different Simultaneous Perturbation Stochastic Approximation (SPSA) gradient
estimates. On the faster timescale, the differential cost function corresponding to a given stationary policy is updated and
an additional averaging is performed for enhanced performance. A proof of convergence to a locally optimal policy is presented.
Next, we discuss a memory efficient implementation that uses a feature-based representation of the state-space and performs
TD(0) learning along the faster timescale. The TD(0) algorithm does not follow an on-line sampling of states but is observed
to do well on our setting. Numerical experiments on a problem of rate based flow control are presented using the proposed
algorithms. We consider here the model of a single bottleneck node in the continuous time queueing framework. We show performance
comparisons of our algorithms with the two-timescale actor-critic algorithms of Konda and Borkar (1999) and Bhatnagar and Kumar (2004). Our algorithms exhibit more than an order of magnitude better performance over those of Konda and Borkar (1999).
相似文献
Shalabh Bhatnagar (Corresponding author)Email: |
7.
Shahid Ud Din Wani Mohammed Iqbal Zargar Mubashir Hussain Masoodi Sultan Alshehri Prawez Alam Mohammed M. Ghoneim Areej Alshlowi H. G. Shivakumar Mohammad Ali Faiyaz Shakeel 《International journal of molecular sciences》2022,23(22)
Silk fibroin (SF), an organic material obtained from the cocoons of a silkworm Bombyx mori, is used in several applications and has a proven track record in biomedicine owing to its superior compatibility with the human body, superb mechanical characteristics, and its controllable propensity to decay. Due to its robust biocompatibility, less immunogenic, non-toxic, non-carcinogenic, and biodegradable properties, it has been widely used in biological and biomedical fields, including wound healing. The key strategies for building diverse SF-based drug delivery systems are discussed in this review, as well as the most recent ways for developing functionalized SF for controlled or redirected medicines, gene therapy, and wound healing. Understanding the features of SF and the various ways to manipulate its physicochemical and mechanical properties enables the development of more effective drug delivery devices. Drugs are encapsulated in SF-based drug delivery systems to extend their shelf life and control their release, allowing them to travel further across the bloodstream and thus extend their range of operation. Furthermore, due to their tunable properties, SF-based drug delivery systems open up new possibilities for drug delivery, gene therapy, and wound healing. 相似文献
8.
Tahreem Fiaz Muhammad Shahid Nadeem Obaid Afzal Abdulmalik S. A. Altamimi Sami I. Alzarea Waleed Hassan Almalki Hafsa Ahmed Khan Iahtisham-Ul-Haq Sharoon Hanook Imran Kazmi Muhammad Mustafa 《International journal of molecular sciences》2022,23(22)
Emotional stress is believed to be associated with increased tumor progression. Stress-induced epigenetic modifications can contribute to the severity of disease and poor prognosis in cancer patients. The current study aimed to investigate the expression profiles along with the prognostic significance of psychological stress-related genes in metastatic breast cancer patients, to rationalize the molecular link between emotional stress and cancer progression. We profiled the expression of selected stress-associated genes (5-HTT, NR3C1, OXTR, and FKBP5) in breast cancer including the stress evaluation of all participants using the Questionnaire on Distress in Cancer Patients–short form (QSC-R10). A survival database, the Kaplan–Meier Plotter, was used to explore the prognostic significance of these genes in breast cancer. Our results showed relatively low expressions of 5-HTT (p = 0.02) and OXTR (p = 0.0387) in metastatic breast cancer patients as compared to the non-metastatic group of patients. The expression of NR3C1 was low in tumor grade III as compared to grade II (p = 0.04). Additionally, the expression of NR3C1 was significantly higher in patients with positive estrogen receptor status. However, no significant difference was found regarding FKBP5 expression in breast cancer. The results suggest a potential implication of these genes in breast cancer pathology and prognosis. 相似文献
9.
为发展创成式的计算机辅助工艺设计,研究了计算机辅助工艺设计系统中工件装夹规划的自动生成算法.基于扩展有向图,建立了零件的公差信息和基准-加工特征关系的数学表示模型,基于公差分析和制造资源能力模型,建立了从单件层到多件层的工件装夹工艺生产算法.该数学模型和算法可自动识别工件的加工特征、装夹基准,并根据制造资源能力和公差分析对装夹进行优化分组,实现装夹分组对工件加工精度的影响最小化,进而生成装夹规程.最后以实例证明了该方法的可行性. 相似文献
10.
Irshad Ahmad Guanglong Zhu Guisheng Zhou Xudong Song Muhi Eldeen Hussein Ibrahim Ebtehal Gabralla Ibrahim Salih Shahid Hussain Muhammad Usama Younas 《International journal of molecular sciences》2022,23(13)
The presence of phyto-hormones in plants at relatively low concentrations plays an indispensable role in regulating crop growth and yield. Salt stress is one of the major abiotic stresses limiting cotton production. It has been reported that exogenous phyto-hormones are involved in various plant defense systems against salt stress. Recently, different studies revealed the pivotal performance of hormones in regulating cotton growth and yield. However, a comprehensive understanding of these exogenous hormones, which regulate cotton growth and yield under salt stress, is lacking. In this review, we focused on new advances in elucidating the roles of exogenous hormones (gibberellin (GA) and salicylic acid (SA)) and their signaling and transduction pathways and the cross-talk between GA and SA in regulating crop growth and development under salt stress. In this review, we not only focused on the role of phyto-hormones but also identified the roles of GA and SA responsive genes to salt stress. Our aim is to provide a comprehensive review of the performance of GA and SA and their responsive genes under salt stress, assisting in the further elucidation of the mechanism that plant hormones use to regulate growth and yield under salt stress. 相似文献