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Heating energy performance and part load ratio characteristics of boiler staging in an office building

Frontiers in Energy 2019年第2期13卷 339-353页

作者： Da Young LEE Byeong Mo SEO Yeo Beom YOON Sung Hyup HONG Jong Min CHOI Kwang Ho LEE Graduate School Hanbat National UniversityDaejeon 305-719South Korea College of Design North Carolina State University RaleighNC 27695-7701USA Department of Mechanical Engineering Hanbat National UniversityDaejeon 305-719South Korea Department of Architectural Engineering Hanbat National UniversityDaejeon 305-719South Korea

Commercial buildings account for significant portions of the total building energy in South Korea and thus a variety of research on the boiler operation related to heating energy in office buildings has been carried out thus far. However, most of the researches have been conducted on the boiler itself, i.e., the part load ratio characteristics and the corresponding gas energy consumption patterns are not analyzed in the existing studies. In this study, the part load ratio and the operating characteristics of gas boiler have been analyzed within an office building equipped with the conventional variable air volume system. In addition, the gas consumption among different boiler staging schemes has been comparatively analyzed. As a result, significant portions of total operating hours, heating load and energy consumption has been found to be in a part load ratio range of 0 through 40% and thus energy consumption is significantly affected by boiler efficiency at low part load conditions. This suggests that boiler operation at the part load is an important factor in commercial buildings. In addition, utilizing sequential boiler staging scheme can save a gas usage of about 7%. For annual heating energy saving, applying the sequential control boiler with a 3:7 proportion staging is considered to be the optimal control algorithm for maximum efficiency of boilers.

关键词： EnergyPlus boiler part load ratio gas con-sumption office building boiler staging

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Rheological Behavior for Polymer Melts and Concentrated Solutions——part Ⅶ: A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts

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Journal of Materials Science & Technology 2001年第3期17卷 375-382页

作者： Mingshi SONG, Chen ZHANG and Guixian HU Research Institute of Polymeric Materials, Beijing University of Chemical Technology, Beijing 100029, China E-mail: wangzhchen@*** Res. Inst. of Polymeric Mat. Beijing Univ. of Chem. Technol. Beijing 100029 China

Based on the molecular theory of non-linear viscoelasticity with constrained entanglements in polymer melts, the material functions in simple shear flow were formulated, the theoretical relations between. eta((gamma) over dot), psi (10)((gamma) over dot) and shear rate ((gamma) over dot), and topologically constrained dimension number n ' and a were derived. Linear viscoelastic parameters (eta (0) and G(N)(0)) and topologically constrained dimension number (n ' a and )over bar>) as a function of the primary molecular weight (M-n), molecular weight between entanglements (M-C) and the entanglement sites sequence distribution in polymer chain were determined. A new method for determination of viscoelastic parameters (eta (0), psi (10), G(N)(0) and J(e)(0)), topologically constrained dimension number (n ', a and v) and molecular weight (M-n, M-c and M-e) from the shear flow measurements was proposed. It was used to determine those parameters and structures of HDPE, making a good agreement between these values and those obtained by other methods. The agreement affords a quantitative verification for the molecular theory of nonlinear viscoelasticity with constrained entanglement in polymer melts.

关键词： Rheological Behavior for Polymer Melts and Concentrated Solutions A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts part

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Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides part Ⅱ: TiO_2, V_2O_5 and MoO_3

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Journal of Materials Science & Technology 2000年第1期16卷 5-14页

作者： Tomoki TSUMURA and Michio INAGAKI (Graduate School of Engineering, Hokkaido University Kita-ku, Sapporo, 060-8628, Japan) Graduate School of Engineering Hokkaido University Kita-ku Sapporo 060-8628 Japan NARD Institute Ltd. 2 Nishinagasu Amagasaki 660-0805 Japan Aichi Institute of Technology Yakusa Toyota 470-0392 Japan

Electrochemical insertion/extraction of Li on cathode materials of anatase type TiO_2, quasilayered structure V_2O_5 and layered structure MoO_3 was measured on samples of which structures were well characterized and showed a wide range of crystallinity. On the basis of experimental results on structure, morphology and charge-discharge characteristics, the effect of crystallinity of the cathode materials on electrochemical Li insertion/extraction pedermance was discussed. These three transition metal oxides were classified as one group on the basis of whether the crystallinity of these oxides affects to the performance or not; LiMn_2O_4 and LiCo_(0.5)O_2 belongs to the former group and TiO_2, V_2O_5 and MoO_3 to the latter.

关键词： Li Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides part V2O5 and MoO3

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Production of Integrated Automotive part in High Pressure Diecasting Process Using Salt Core

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Journal of Rare Earths 2004年第Z2期22卷 57-60页

作者： Ki-Bae Kim Hyun-Kwang Seok Jun-Su Kim Advanced Materials Research Center Korea Institute of Science and TechnologyP.O.Box 131CheongryangSeoul130-650Korea Advanced Materials Research CenterKorea Institute of Science and TechnologyP.O.Box 131CheongryangSeoul130-650Korea Research & Development CenterTechnology Union Co.Ltd742-1Paeksok-dongChonan-siChungchongnam-do330-220Korea

A new concept of salt core, a melting temperature of which is lower than the solidus temperature of cast alloy,was introduced to produce an integrated casting part having a complicated inner shape or requiring under-cut in high pressure die casting or squeeze casting process. A salt core, named a fusible core in this paper because the salt core can be easily extracted just as holding at a temperature under a solidus temperature of a casting alloy, was developed and applied to produce a fuel control part for automotive GDI engine in high pressure diecasting machine. A different salt material of a lower melting temperature than that of A1 alloy was mixed with a different ceramic particulate to improve a thermo-physical property of fusible core. The thermo-physical property of the fusible core was measured and a weight faction of the ceramic particulate was optimized. The selected core materials were poured in metallic mold by gravity to produce a fusible core for a fuel control part for automotive GDI engine. The fuel control part, which the fusible core was included inside, was successful to fabricate in a conventional diecasting machine with no melting of fusible core during casting.

关键词： salt core high pressure diecasting casting part for automotive fusible core

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Structure of the Intermetallic Compound Ni_3Al Synthesized under Compression of the Powder Mixture of Pure Elements part Ⅱ: Influence of Alloying by Boron on the Phase Composition and the Microstructure of Grains of the Main Phase

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Journal of Materials Science & Technology 2000年第1期16卷 15-18页

作者： M. V.Fedorischeva, V.E.Ovcharenko,O.B.Perevalova and E.V.Kozlov (Institute of Strength Physics and Materials Science, Russian Academy of Sciences, Siberian Branch.Tomsk, Russia) Institute of Strength Physics and Materials Science Russian Academy of Sciences Siberian Branch Tomsk Russian Federation

The Ni_3B phase was formed when boron (0.5 at. pct B) was added to the intermetallic of sto- ichiometric and off-stoichiometric (Ni-24 at. pct Al) compounds. In the alloy of stoichiometric composition the particles of Ni_3B phase has the size around 0.1μm and is located on the grain boundary of the main phase. The decreasing of concentrations of Al in the ofF-stoichiometric alloy leads to increase in the degree of the long-range order parameter, increasing the concen- trations of boron in the solid solution and decreasing its localization on the grain boundary. Microalloying of boron leads to increasing in the fraction of grain monodomains with disloca- tions up to 0.7 in the alloy of the off-stoichiometric composition and up to 1 in the alloy of the stoichiometric composition. It was established the correlation between the degree of the concentration inhomogeneity, average density of the dislocations and the average long range-order parameter.

关键词： Al part Structure of the Intermetallic Compound Ni3Al Synthesized under Compression of the Powder Mixture of Pure Elements Ni

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Geological characteristics,metallogenic background,and genesis of the Tongyu VHMS copper deposit in the west part of the North Qinling,Shaanxi Province

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Science China Earth Sciences 2010年第10期53卷 1460-1485页

作者： Ben Lee LaiMin Zhu GuoWei Zhang Bo Guo HuJun Gong AnPing Yao NW Univ Xian Dept Geol State Key Lab Continental Dynam Xian 710069 Peoples R China

The Tongyu volcanic-hosted massive sulfide(VHMS) copper deposit is located in the west part of the North Qinling(NQL),Shaanxi *** we report geological features and trace elemental characteristics of ores,mineralized rocks,and volcanic host rocks of this *** also conducted in situ zircon U-Pb and Lu-Hf LA-ICP-MS dating and lithogeochemical study of the Meigou granodiorite,which is intruded in the south of the Tongyu mining *** is inferred that the volcanic host rocks of the Tongyu Cu deposit belong to calc-alkaline island arc volcanic rocks,and the volcanic host rocks and the ore-forming materials share common material *** subduction of the Paleo-Qinling oceanic slab at around 472 Ma,high oxygen-fugacity aqueous fluid released by dehydration reaction of the subducting slab rose into the mantle wedge,leached Cu and other metal elements,and triggered partial melting of the mantle *** with the ore-forming materials,the arc calc-alkaline magmas erupted and formed the Tongyu VHMS *** weighted average zircon U-Pb age of the Meigou granodiorite is 439.3±3 Ma,suggesting its genesis is associated with the subduction event of the Paleo-Qinling oceanic plate around 440 *** terms of the granitoid's geochemical characteristics,the Mg#,Ni,and Cr contents are *** show strongly fractionated patterns with unobvious Eu *** contents are high while Y contents are low,resulting in high Sr/Y ***-stage zircon Hf model ages mostly range between 908 and 723 Ma,with εHf(t)>***,we classify Meigou granodiorite as island arc granite with adakitic geochemical *** was generated by interaction between mantle wedge and melt produced by partial melting of the subducted basaltic slab of the Paleo-Qinling *** Tongyu VHMS deposit was formed in the island arc tectonic setting during Ordovician-Silurian between 439.3±3 Ma and 472±11 *** volcanic exhalation-sedimentation,which was contemporaneous with t

关键词： west part of the North Qinling VHMS copper deposit metallogenic background and genesis

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Diffractive-optical processing of temporal signals, part Ⅱ: optical tapped-delay line

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Chinese Optics Letters 2006年第5期4卷 262-264页

作者： Jürgen Jahns Adolf W.Lohmann LG Optical Information Technology University of HagenGermany Lst.Multimedia and Signal Processing University of Erlangen-NürnbergGermany

The topic of this presentation is the utilization of time for optical information processing. As clock rates in computing and communication systems increase and reach the THz border, optical techniques for signal filtering, shaping and clock distribution become attractive. We discuss the use of optics in temporal processing and consider in particular diffractive solutions, in this paper, we describe the use of double diffraction for implementing an ultrafast tapped-delay line.

关键词： optical tapped-delay line Diffractive-optical processing of temporal signals part

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The features of gravity field and deep structure in western part of the South Yellow Sea

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Chinese Science Bulletin 2000年第8期45卷 759-764页

作者： WANG Qianshen1 & AN Yulin1. Institute of Geophysics, Chinese Academy of Sciences, Beijing 100101, China 2. Chinese University of Geology, Beijing 100083, China Institute of Geophysics Chinesc Academy of Sciences Beijing China Chinese University of Geology Beijing China

The gravity data from the sea region to the west of 124° E of the South Yellow Sea have been processed and the feature of gravity fields analyzed. An experience relationship formula on the filter wavelength and corresponding depth has been put forward. Combined with the geological and seismic data, the deep tectonic framework and structural characters as well as possible favourable prospecting district for hydrocarbon in the South Yellow Sea have been discussed and analyzed.

关键词： western part of the South Yellow Sea gravity field deep structure.

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Parallelized deformable part models with effective hypothesis pruning

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Computational Visual Media 2016年第3期2卷 245-256页

作者： Zhi-Min Zhou Xu Zhao Department of Automation Shanghai Jiao Tong University

As a typical machine-learning based detection technique, deformable part models(DPM)achieve great success in detecting complex object categories. The heavy computational burden of DPM,however, severely restricts their utilization in many real world applications. In this work, we accelerate DPM via parallelization and hypothesis pruning. Firstly,we implement the original DPM approach on a GPU platform and parallelize it, making it 136 times faster than DPM release 5 without loss of detection ***, we use a mixture root template as a prefilter for hypothesis pruning, and achieve more than 200 times speedup over DPM release 5, apparently the fastest implementation of DPM yet. The performance of our method has been validated on the Pascal VOC2007 and INRIA pedestrian datasets, and compared to other state-of-the-art techniques.

关键词： deformable part models(DPM) GPU parallel computing hypothesis pruning visual detection

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Evidence for natural fire and climate history since 37 ka BP in the northern part of the South China Sea

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Science China Earth Sciences 2000年第5期43卷 487-493页

作者：孙湘君李逊陈怀成 Institute of Botany Chinese Academy of Sciences Beijing 100093 China Laboratory of Marine Geology Tongji University Shanghai 200092 China

The history of natural fire since 37 kaBP and its relationship to climate for the northern part of the South China Sea are revealed from the statistic study of charcoal particles and associated pollen data from deep sea core 17940 (20° 07’N, 117° 23’E, 1 727 m in water depth). Our study indicates that, during the last glaciation, the concentration of charcoal and the ratio of concentration between charcoal and terrestrial pollen are much higher than that of the Holocene. This can be explained as the relatively high strength and frequency of natural fire during glaciation which is probably due to the drier climate; during the Last Glacial Maximum (LGM), the substantial rising of the concentration of large and medium charcoal particles probably suggests the local source area of the natural fires, i.e. the exposed continental shelf; moreover, the correlation between charcoal concentration with different size and pollen percentage may elucidate different transport dynamics. During the glacial time,

关键词： northern part of South China Sea charcoal natural fire.

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