52 research outputs found

    A Model for Performance Evaluation of Climate-Adaptive Building Envelopes Using Parametric Models and Multi-Criteria Optimization

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    The goal of this research is to enable designers to evaluate the performance of Climate-Adaptive Building Envelopes (CABE) to make better decisions at the conceptual design stage. This goal was accomplished by delivering three contributions to the fields of parametric modeling, building performance simulation, and multi-criteria optimization. There are three main challenges in CABE performance evaluation that cannot be overcome by conventional methods: 1) defining a suitable relationship between environmental factors and their thresholds by focusing on a given condition in CABE behavior control; 2) representing a CABEā€™s time-series behavior by using a single Building Performance Simulation (BPS) model; and 3) managing information related to a CABEā€™s performance and behavior for use in design decisions. To overcome these issues, this research developed a new CABE performance evaluation method called Parametric Behavior Maps (PBM), which makes three key contributions. First, the PBM method is able to generate a CABE operation schedule as an Hourly Behavior of Openness (HBOO) scenario to evaluate CABE performance using a single BPS model. Second, the PBM method produces more reliable outcomes than the conventional process, especially in terms of the time-lag effect of thermal performance. Third, the use of a Function-based Behavior Control System (FBCS) for the CABE efficiently facilitates a multi-criteria optimization process by progressively simulating alternative HBOO scenarios, allowing designers to choose the best scheme. These three contributions offer logical proof that the use of parametric modeling and simulation tools can help designers make better decisions regarding CABE alternatives. The PBM method was validated by investigating several test cases. First, static shading scenarios were developed using the PBM; the amount of incoming solar radiation was then compared with outcomes from the BPS with static shading. Second, indoor temperature profiles were simulated using the PBM method and an HBOO scenario; the results were compared with the outcomes obtained from the existing method, in order to determine the PBMā€™s reliability. Third, the integration of the PBM method and evolutionary multi-objective optimization technique illustrates the usefulness of the FBCS in CABE performance optimization

    A Model for Performance Evaluation of Climate-Adaptive Building Envelopes Using Parametric Models and Multi-Criteria Optimization

    Get PDF
    The goal of this research is to enable designers to evaluate the performance of Climate-Adaptive Building Envelopes (CABE) to make better decisions at the conceptual design stage. This goal was accomplished by delivering three contributions to the fields of parametric modeling, building performance simulation, and multi-criteria optimization. There are three main challenges in CABE performance evaluation that cannot be overcome by conventional methods: 1) defining a suitable relationship between environmental factors and their thresholds by focusing on a given condition in CABE behavior control; 2) representing a CABEā€™s time-series behavior by using a single Building Performance Simulation (BPS) model; and 3) managing information related to a CABEā€™s performance and behavior for use in design decisions. To overcome these issues, this research developed a new CABE performance evaluation method called Parametric Behavior Maps (PBM), which makes three key contributions. First, the PBM method is able to generate a CABE operation schedule as an Hourly Behavior of Openness (HBOO) scenario to evaluate CABE performance using a single BPS model. Second, the PBM method produces more reliable outcomes than the conventional process, especially in terms of the time-lag effect of thermal performance. Third, the use of a Function-based Behavior Control System (FBCS) for the CABE efficiently facilitates a multi-criteria optimization process by progressively simulating alternative HBOO scenarios, allowing designers to choose the best scheme. These three contributions offer logical proof that the use of parametric modeling and simulation tools can help designers make better decisions regarding CABE alternatives. The PBM method was validated by investigating several test cases. First, static shading scenarios were developed using the PBM; the amount of incoming solar radiation was then compared with outcomes from the BPS with static shading. Second, indoor temperature profiles were simulated using the PBM method and an HBOO scenario; the results were compared with the outcomes obtained from the existing method, in order to determine the PBMā€™s reliability. Third, the integration of the PBM method and evolutionary multi-objective optimization technique illustrates the usefulness of the FBCS in CABE performance optimization

    Toll-like receptor 2 contributes to chemokine gene expression and macrophage infiltration in the dorsal root ganglia after peripheral nerve injury

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    <p>Abstract</p> <p>Background</p> <p>We have previously reported that nerve injury-induced neuropathic pain is attenuated in toll-like receptor 2 (TLR2) knock-out mice. In these mice, inflammatory gene expression and spinal cord microglia actvation is compromised, whereas the effects in the dorsal root ganglia (DRG) have not been tested. In this study, we investigated the role of TLR2 in inflammatory responses in the DRG after peripheral nerve injury.</p> <p>Results</p> <p>L5 spinal nerve transection injury induced the expression of macrophage-attracting chemokines such as CCL2/MCP-1 and CCL3/MIP-1 and subsequent macrophage infiltration in the DRG of wild-type mice. In TLR2 knock-out mice, however, the induction of chemokine expression and macrophage infiltration following nerve injury were markedly reduced. Similarly, the induction of IL-1Ī² and TNF-Ī± expression in the DRG by spinal nerve injury was ameliorated in TLR2 knock-out mice. The reduced inflammatory response in the DRG was accompanied by attenuation of nerve injury-induced spontaneous pain hypersensitivity in TLR2 knock-out mice.</p> <p>Conclusions</p> <p>Our data show that TLR2 contributes to nerve injury-induced proinflammatory chemokine/cytokine gene expression and macrophage infiltration in the DRG, which may have relevance in the reduced pain hypersensitivity in TLR2 knock-out mice after spinal nerve injury.</p

    Hafnium metallocene compounds used as cathode interfacial layers for enhanced electron transfer in organic solar cells

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    We have used hafnium metallocene compounds as cathode interfacial layers for organic solar cells [OSCs]. A metallocene compound consists of a transition metal and two cyclopentadienyl ligands coordinated in a sandwich structure. For the fabrication of the OSCs, poly[3,4-ethylenedioxythiophene]:poly(styrene sulfonate), poly(3-hexylthiophene-2,5-diyl) + [6,6]-phenyl C61 butyric acid methyl ester, bis-(ethylcyclopentadienyl)hafnium(IV) dichloride, and aluminum were deposited as a hole transport layer, an active layer, a cathode interfacial layer, and a cathode, respectively. The hafnium metallocene compound cathode interfacial layer improved the performance of OSCs compared to that of OSCs without the interfacial layer. The current density-voltage characteristics of OSCs with an interfacial layer thickness of 0.7 nm and of those without an interfacial layer showed power conversion efficiency [PCE] values of 2.96% and 2.34%, respectively, under an illumination condition of 100 mW/cm2 (AM 1.5). It is thought that a cathode interfacial layer of an appropriate thickness enhances the electron transfer between the active layer and the cathode, and thus increases the PCE of the OSCs

    LEED, Its Efficacy and Fallacy in a Regional Contextā€”An Urban Heat Island Case in California

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    The use of energy in the building sector has increased rapidly over the past two decades. Accordingly, various building assessment methods have developed in green building practices. However, the questions still remain in regard to how positively green buildings affect regional surroundings. This study investigates the possible relationship between LEED-certified buildings and urban heat island effect. Using GIS with spatial regression, the study found that constructing an LEED building in a 30-m boundary could possibly lower the temperature of the surrounding environment by 0.35 Ā°C. Also, having a higher certification level, such as Gold or Platinum, increased the lowering effect by 0.48 Ā°C, while a lower certification level, such as Certified or Silver, had a lowering effect of 0.26 Ā°C. Although LEED has gained a substantial amount of interest and skepticism at the same time, the study results could be a potential sign that the Sustainable Sites Credits or energy-efficient materials play a positive role in lowering the temperature

    Microstructural evolution of ZrO 2

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    Effect Of Thermal Treatment On The Chemical Resistance Of Polydimethylsiloxane For Microfluidic Devices

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    We investigated the use of thermally treated polydimethylsiloxane (PDMS) for chemically-resistant microchannels. When the PDMS underwent the thermal treatment at 300 Ā°C, swelling was reduced and the surface of the PDMS microfluidic channel endured well in the extracting media such as dichloromethane. Furthermore, despite the small decrease in size after thermal treatment, both the channel shape and transparency were maintained without showing fluid leakage. The thermally treated PDMS had more hydrophilic properties compared to the untreated PDMS. A single step post-casting process described in this work does not require complex chemical treatments or introduction of foreign materials to the host PDMS substrate, thus expanding the application area of PDMS-based microfluidics. Ā© 2013 IOP Publishing Ltd

    Surface Modification Of Carbon Post Arrays By Atomic Layer Deposition Of Zno Film

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    The applicability of atomic layer deposition (ALD) process to the carbon microelectromechanical system technology was studied for a surface modification method of the carbon post electrodes. A conformal coating of the ALD-ZnO film was successfully demonstrated on the carbon post arrays which were fabricated by the traditional photolithography and subsequent two-step pyrolysis. A significant Zn diffusion into the underlying carbon posts was observed during the ALD process. The addition of a sputter-deposited ZnO interfacial layer efficiently blocked the Zn diffusion without altering the microstructure and surface morphology of the ALD-ZnO film. Ā© 2011 American Scientific Publishers
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