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Broadcast-Based Spatial Queries

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Journal of Computer Science & Technology 2005年第6期20卷 811-821页

作者： Kwang-jin Park Moon-Bae Song Chong-Sun hwang Department of Computer Science and Engineering Korea University 5-1 Anam-Dong Seongbuk-Ku Seoul 136-701 Korea

Indexing techniques have been developed for wireless data broadcast environments, in order to conserve the scarce power resources of the mobile clients. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, the broadcast-based spatial query processing methods （BBS） are presented for the location-based services. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, a sequential prefetehing and caching scheme is designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

关键词： broadcasting location-aware caching prefetching mobile computing

Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao Lin jin Zhou Shu-Ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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Arabidopsis BAG1 Functions as a Cofactor in Hsc70-Mediated Proteasomal Degradation of Unimported Plastid Proteins

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Molecular Plant 2016年第10期9卷 1428-1431页

作者： Dong Wook Lee Su jin Kim young Jun Oh Bongsoo Choi Juhun Lee Inhwan hwang Division of Integrative Biosciences and Biotechnology Pohang University of Science and Technology Pohang 790-784 Korea

Dear Editor,Eliminating misfolded or mistargeted proteins is crucial for cell viability because these proteins accumulate as non-specific aggregates, which can be toxic to the cell （Lee et al., 2009; Sroka et al., 2009）. Previously, we have shown that in ppi2 （plastid protein import 2） mutant plants, the transcript levels of Hsc70-4 （one isoform of the Hsc70 family） and CHIP （an E3 ligase） were highly upregulated, which ultimately plays crucial roles in proteasomal degradation of unimported plastid proteins （Lee et al., 2009）. We also found that, along with those of Hsc70-4 and CHIP, the transcript level of AtBAG1 （Arabidopsis thaliana Bcl2-associated athanogene 1） in the ppi2 mutant was 2.38-fold higher than that in the wild-type （Lee et al., 2009）.

关键词： ARABIDOPSIS proteins PLASTIDS

Alkaline leaching mechanism of MSWI bottom ash: the pivotal role of Si(Al) chemical bonding environments

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Science China Technological Sciences 2025年

作者： Ningning SHAO Zekun JIAO Weipeng FENG Yu jin Fanlong KONG Zhijun DONG Zuotai ZHANG Institute of Technology for Marine Civil Engineering Shenzhen Institute of Information Technology (SZIIT) Guizhou NASH Ecological Technology Co. LTD School of Environmental Science and Engineering Key Laboratory of Municipal Solid Waste Recycling Technology and Management of Shenzhen City Southern University of Science and Technology (SUSTech)

Municipal solid waste incineration bottom ash(MSWIBA) is a complex assemblage of aluminosilicate materials encompassing diverse solid wastes. Thus, its complexity poses great challenges to their resource utilization. For the sake of the alkali activation use of MSWIBA, this work focused on the characterizations and alkaline leaching experiments of various classified MSWIBA after sorting. Among the different categories of MSWIBA, waste glass(BA-G) and other unidentified slags(BA-O) were identified as potential precursors for alkali activation use. The alkaline leaching experiments proved that alkaline concentration, reaction temperature, reaction time, and raw material classification influenced the leaching process and results. Among these, the Si/Al chemical bonding environments from the material type played a pivotal role. When the materials had Qn(n>2) as the primary bonding structure, steric hindrance by the chain frameworks affected the alkali dissolution process, resulting in gradual disintegration from the outer layers inward. For the materials dominated by Q1frameworks, OH-could penetrate the frameworks, leading to their rapid depolymerization and outward dissolution. Overall, the Si/Al bonding environment played a crucial role in alkaline dissolution, providing theoretical guidance for classifying the alkali-activation utilization of MSWIBA and other aluminosilicate solid wastes.

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Broadband low-frequency sound absorption of multifunctional composite metastructure

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Science China Technological Sciences 2025年

作者： Yilong YANG Shanshan LIU Yan LI Tong GAO Yongdong PAN Yong LI Yabin jin School of Aerospace Engineering and Applied Mechanics Tongji University Institute of Acoustics School of Physics Science and Engineering Tongji University Shanghai Institute of Aircraft Mechanics and Control State International Joint Research Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical University Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power Engineering East China University of Science and Technology

In this study, we fabricated multifunctional metastructures from carbon fiber-reinforced plastic composites using additive manufacturing technology. These metastructures are characterized by their lightweight, load-bearing capacity, and broadband low-frequency sound absorption properties. The metastructure consists of 36 unit cells, and non-local coupling mechanism was considered for designing the sound absorption performance. We developed an acoustic impedance theory tailored for the metastructure, facilitating an analysis of thermal and viscous dissipation mechanisms. It is proven theoretically and experimentally that the proposed composite metastructure can achieve a noise reduction with an average sound absorption coefficient greater than 0.9 across frequencies in the rage of 330–1500 Hz. We also studied the metastructure’s quasi-static and cyclic compression performance, confirming its efficient absorption capabilities after cyclic compression. The proposed design and additive manufacturing method for composite metastructures provides a novel pathway for creating lightweight, multifunctional structures with diverse applications, such as aerospace engineering.

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Effect of nanoclay on properties of porous PVdF membranes

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 141-147页

作者： Hae-young hwang Deuk-Ju KIM Hyung-Jun KIM young-Taik HONG Sang-Yong NAM School of Materials Science and Engineering Engineering Research Institute i-Cube Center Gyeongsang National University Fuel Cell Research Center Korea Institute of Science and Technology Seoul 136-791 Korea Energy Material Research Center Korea Research Institute of Chemical Technology Daejeon 305-600 Korea

The main requirements for battery separators are high porosity which can serve pathways of lithium ion and space for gel electrolytes to impregnate in a membrane and mechanical strength to allow easy handling for battery assembly. Generally, it appears the trade-off relationship between the porosity and mechanical strength of the membrane. PVdF composite membranes containing nano-size clays were used to improve the mechanical strength of the membrane without affecting the membrane porosity. The composite membranes were prepared by phase inversion method controlling the membrane preparation conditions such as retention time. The resultant membranes show increased mechanical properties with similar membrane porosity around 80 % compared to the pristine PVdF membrane. Incorporation of nonoclay can be considered as an effective method to improve the mechanica! strength in porous membrane supports, especially in a separator.

关键词： Li-ion battery separator poly(vinylidene fluoride) nanocomposite

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Thick free-standing electrode based on carbon-carbon nitride microspheres with large mesopores for high-energy-density lithium-sulfur batteries

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Carbon Energy 2021年第3期3卷 410-423页

作者： Hui-Ju Kang Tae-Gyu Lee Heejin Kim Jae-Woo Park Hyun jin hwang Hyeonseok hwang Kwang-Suk Jang Hae jin Kim Yun Suk Huh Won Bin Im young-Si Jun Department of Advanced Chemicals&Engineering Chonnam National UniversityBuk-guGwangjuRepublic of Korea Division of Analytical Science Korea Basic Science Institute(KBSI)Yuseong-guDaejeonRepublic of Korea School of Chemical Engineering Chonnam National UniversityBuk-guGwangjuRepublic of Korea Department of Applied Chemistry Hanyang UniversityAnsanGyeonggi-doRepublic of Korea Department of Biological Engineering Inha UniversityNam-guIncheonRepublic of Korea Division of Materials Science and Engineering Hanyang UniversitySeongdong-guSeoulRepublic of Korea

The development of sulfur cathodes with high areal capacity and high energy density is crucial for the practical application of lithium-sulfur batteries(LSBs).LSBs can be built by employing(ultra)high-loading sulfur cathodes,which have rarely been realized due to massive passivation and ***,microspheres of a carbon-carbon nitride composite(C@CN)with large mesopores are fabricated via molecular cooperative *** the C@CN-based electrodes,the effects of the large mesopores and N-functional groups on the electrochemical behavior of sulfur in LSB cells are thoroughly investigated under ultrahigh sulfur-loading conditions(>15 mgS cm^(-2)).Furthermore,for high-energy-density LSBs,the C@CN powders are pelletized into a thick free-standing electrode(thickness:500^m;diameter:11 mm)via a simple briquette process;here,the total amount of energy stored by the LSB cells is 39 mWh,corresponding to a volumetric energy density of 440 Wh L-1 with an areal capacity of 24.9 and 17.5 mAh cm^(-2) at 0.47 and 4.7 mA cm^(-2),respectively(at 24mgS cm^(-2)).These results have significantly surpassed most recent records due to the synergy among the large mesopores,(poly)sulfide-philic surfaces,and thick *** developed strategy with its potential for scale-up successfully fills the gap between laboratory-scale cells and practical cells without sacrificing the high areal capacity and high energy density,providing a solid foundation for the development of practical LSBs.

关键词： briquette process carbon nitride free-standing electrode high energy density lithium-sulfur batteries mesopores

Diagnosis parameters of mold filling pattern for optimization of a casting system

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China Foundry 2012年第4期9卷 376-380页

作者： Jun-Ho Hong young-Sim Choi Ho-young hwang e-Design Center Korea Institute of Industrial Technology e-Design Center Korea Institute of Industrial TechnologyIncheonKorea

For optimal design of a gating system,the setting of diagnosis parameters is very *** this study,the permanent mold casting process was selected because most of the other casting processes have more complicated factors that influence the mold filling pattern compared to the permanent mold casting process,such as the surface roughness of mold,gas generation from the mold wash and binder of sand mold,and the gas permeability through a sand mold,*** diagnosis parameters(flow rate difference and arrival time difference) of molten metal flow pattern in the numerical simulation are suggested for design of an optimum casting system with a permanent *** results show that the arrival time difference can be used as one important diagnosis parameter of the complexity of the runner system and its usefulness has been verified via making aluminum parts using permanent mold casting(Fig.9).

关键词： mold filling pattern optimum casting system diagnosis parameter permanent mold casting process

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Hydrangea serrata extract exerts tumor inhibitory activity against hepatocellular carcinoma HepG2 cells via inducing p27/CDK2-mediated cell cycle arrest and apoptosis

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Asian Pacific Journal of Tropical Biomedicine 2024年第2期14卷 65-72,I0002-I0005页

作者： Ye-eun Kim Jeonghye hwang Ki-young Kim Graduate School of Biotechnology Kyung Hee UniversitySeocheonGiheungYonginGyeonggi-do 446-701Republic of Korea Department of Genetics and Biotechnology College of Life SciencesKyung Hee UniversitySeocheonGiheungYonginGyeonggi-do 446-701Republic of Korea

Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying ***:The effects of Hydrangea serrata extract on growth inhibition of tumor cells and spheroids were assessed using MTT and 3D culture *** real-time PCR and Western blot analyses were employed to investigate the changes in mRNA and protein expression levels of molecules related to cell cycle and ***:Hydrangea serrata extract effectively inhibited the growth of both tumor cells and *** extract also significantly upregulated p27 mRNA expression and downregulated CDK2 mRNA expression,leading to cell cycle ***,increased BAX/Bcl-2 ratio as well as caspase-9 and-3 were observed after treatment with Hydrangea serrata extract,indicating the induction of tumor cell ***:Hydrangea serrata extract has the potential to alleviate tumors by effectively modulating cell-cycle-related gene expressions and inducing apoptosis,thereby inhibiting tumor growth.

关键词： Hydrangea serrata Hepatocellular carcinoma Liver cancer Anticancer Cell cycle arrest Apoptosis