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成都地铁换乘及换乘效率评价研究 预览
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作者 何林 何珍 《价值工程》 2019年第29期140-142,共3页
地铁换乘站一经建成,站内各种换乘设施、换乘方式等都已基本确定,无法进行大规模改建。分析成都地铁线网客流、换乘客流、乘客行为特征;研究乘客换乘过程,梳理换乘流线;建立地铁网络换乘效率评价指标体系。通过成都地铁火车南站实例研究... 地铁换乘站一经建成,站内各种换乘设施、换乘方式等都已基本确定,无法进行大规模改建。分析成都地铁线网客流、换乘客流、乘客行为特征;研究乘客换乘过程,梳理换乘流线;建立地铁网络换乘效率评价指标体系。通过成都地铁火车南站实例研究,分析乘客换乘流线,找出存在问题并提出解决措施。 展开更多
关键词 换乘 换乘流线 换乘效率评价
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原油转驳船海上作业定位能力需求分析 预览
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作者 胡开业 丁勇 +2 位作者 王宏伟 熊大鹏 杨笛 《船舶与海洋工程学报:英文版》 CSCD 2019年第2期205-212,共8页
In response to the development of deep-sea oil and gas resources,which require a high degree of cooperation by crude oil transportation equipment,a new type of ship known as the cargo transfer vessel(CTV)has been deve... In response to the development of deep-sea oil and gas resources,which require a high degree of cooperation by crude oil transportation equipment,a new type of ship known as the cargo transfer vessel(CTV)has been developed.To provide a theoretical reference for the design and equipment of the CTV’s dynamic positioning system,in this paper,we take the new deepwater CTVas the study object and theoretically and numerically analyze its operation,wind load,current load,wave load,and navigational resistance in a range of Brazilian sea conditions with respect to its positioning and towing modes.We confirm that our proposed method can successfully calculate the total environmental load of the CTVand that the CTV is able to operate normally under the designed sea conditions. 展开更多
关键词 CARGO TRANSFER VESSEL Wind LOAD Current LOAD Wave LOAD DP CAPABILITY Oil TRANSFER operation
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Ab initio investigation of excited state dual hydrogen bonding interactions and proton transfer mechanism for novel oxazoline compound
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作者 王玉生 贾敏 +2 位作者 张巧丽 宋晓燕 杨大鹏 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期309-314,共6页
Owing to the importance of excited state dynamical relaxation, the excited state intramolecular proton transfer(ESIPT) mechanism for a novel compound containing dual hydrogen bond(abbreviated as "1-enol") is... Owing to the importance of excited state dynamical relaxation, the excited state intramolecular proton transfer(ESIPT) mechanism for a novel compound containing dual hydrogen bond(abbreviated as "1-enol") is studied in this work.Using density functional theory(DFT) and time-dependent density functional theory(TDDFT) method, the experimental electronic spectra can be reproduced for 1-enol compound. We first verify the formation of dual intramolecular hydrogen bonds, and then confirm that the dual hydrogen bond should be strengthened in the first excited state. The photo-excitation process is analyzed by using frontier molecular orbital(HOMO and LUMO) for 1-enol compound. The obvious intramolecular charge transfer(ICT) provides the driving force to effectively facilitate the ESIPT process in the S1 state. Exploration of the constructed S0-state and S1-state potential energy surface(PES) reveals that only the excited state intramolecular single proton transfer occurs for 1-enol system, which makes up for the deficiencies in previous experiment. 展开更多
关键词 excited state INTRAMOLECULAR PROTON TRANSFER potential energy surface INTRAMOLECULAR charge TRANSFER infrared VIBRATIONAL spectra
Comparison between direct repair and human acellular nerve allografting during contralateral C7 transfer to the upper trunk for restoration of shoulder abduction and elbow flexion 预览
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作者 Liang Li Wen-Ting He +3 位作者 Ben-Gang Qin Xiao-Lin Liu Jian-Tao Yang Li-Qiang Gu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第12期2132-2140,共9页
Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct re... Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct repair can only be performed in some selected cases, and partial procedures still require autografts, which are the gold standard for repairing neurologic defects. As symptoms often occur after autografting, human acellular nerve allografts have been used to avoid concomitant symptoms. This study investigated the quality of shoulder abduction and elbow flexion following direct repair and acellular allografting to evaluate issues requiring attention for brachial plexus injury repair. Fifty-one brachial plexus injury patients in the surgical database were eligible for this retrospective study. Patients were divided into two groups according to different surgical methods. Direct repair was performed in 27 patients, while acellular nerve allografts were used to bridge the gap between the contralateral C7 nerve root and upper trunk in 24 patients. The length of the harvested contralateral C7 nerve root was measured intraoperatively. Deltoid and biceps muscle strength, and degrees of shoulder abduction and elbow flexion were examined according to the British Medical Research Council scoring system;meaningful recovery was defined as M3–M5. Lengths of anterior and posterior divisions of the contralateral C7 in the direct repair group were 7.64 ± 0.69 mm and 7.55 ± 0.69 mm, respectively, and in the acellular nerve allografts group were 6.46 ± 0.58 mm and 6.43 ± 0.59 mm, respectively. After a minimum of 4-year follow-up, meaningful recoveries of deltoid and biceps muscles in the direct repair group were 88.89% and 85.19%, respectively, while they were 70.83% and 66.67% in the acellular nerve allografts group. Time to C5/C6 reinnervation was shorter in the direct repair group compared with the acellular nerve allografts group. Direct repair facilitated the restoration of shoulder abduction and elbow flexion 展开更多
关键词 NERVE REGENERATION CONTRALATERAL C7 NERVE root TRANSFER NERVE graft brachial plexus avulsion injury direct REPAIR human acellular NERVE allograft shoulder function elbow function NERVE TRANSFER phrenic NERVE accessary NERVE neural REGENERATION
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Surface-to-bed heat transfer for high-density particles in conical spouted and spout–fluid beds
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作者 Onur Yaman Gorkem Kulaha Murat Koksalb 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第1期35-47,共13页
Bed-to-surface heat transfer experiments from a vertically submerged cylindrical surface were conducted in laboratory-scale (Dc = 25 cm) conical spouted and spout–fluid beds at two different conical angles (31° ... Bed-to-surface heat transfer experiments from a vertically submerged cylindrical surface were conducted in laboratory-scale (Dc = 25 cm) conical spouted and spout–fluid beds at two different conical angles (31° and 66°) in the high particle density range (2500 kg/m3 ≤ρp ≤ 6000 kg/m3). The effects of the bed design parameters (conical angle and inlet diameter of spouting gas entrance) and operating conditions (static bed height, particle size, density, and spouting and fluidization gas flow rates) on the heat transfer characteristics were investigated in detail. The heat transfer coefficients were shown to be dependent on the density and size of the particles. The minimum stable spouting velocities of the denser and larger particles were higher, which led to higher operational spouting velocities and thereby resulted in higher heat transfer coefficients. The positive effect of increasing the particle diameter on heat transfer was more pronounced in the spout and at the spout–annulus interface, whereas this effect was diminished in the annulus region. The heat transfer coefficient increased with increasing spouting gas velocity up to 1.0Ums–1.1Ums, beyond which no significant change was observed regardless of the particle type. The heat transfer coefficient in the annulus decreased with increasing conical angle because of reduced particle circulation. The spout–fluid operation increased the heat transfer coefficient by a maximum of 10% at the expense of a significant increase of the total gas flow rate. This result was attributed to the inability of the fluidizing gas to penetrate the annulus. An empirical correlation for the average heat transfer coefficient in the annulus was also proposed based on the data obtained in this work. 展开更多
关键词 Conical spouted BED Spout–fluid BED Bed-to-surface HEAT TRANSFER Submerged HEAT TRANSFER SURFACE
Transfer matrix method for multibody systems(Rui method) and its applications
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作者 RUI XiaoTing WANG Xun +1 位作者 ZHOU QinBo ZHANG JianShu 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第5期712-720,共9页
The transfer matrix method for multibody systems, namely the 'Rui method', is a new method for studying multibody system dynamics, which avoids the global dynamics equations of the system, keeps high computati... The transfer matrix method for multibody systems, namely the 'Rui method', is a new method for studying multibody system dynamics, which avoids the global dynamics equations of the system, keeps high computational speed, and allows highly formalized programming. It has been widely applied to scientific research and key engineering of lots of complex mechanical systems in 52 research directions. The following aspects regarding the transfer matrix method for multibody systems are reviewed systematically in this paper: history, basic principles, formulas, algorithm, automatic deduction theorem of overall transfer equation, visualized simulation and design software, highlights, tendency, and applications in 52 research directions in over 100 key engineering products. 展开更多
关键词 MULTIBODY system dynamics TRANSFER matrix METHOD for MULTIBODY systems Rui METHOD automatic DEDUCTION THEOREM of overall TRANSFER equation theory computation software APPLICATIONS
Research on the Heat Transfer Characteristics of a Loop Heat Pipe Used as Mainline Heat Transfer Mode for Spacecraft
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作者 WANG Lu MIAO Jianyin +4 位作者 GONG Mingming ZHOU Qiangu LIU Changu ZHANG Hongxing FAN Hanlin 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期736-744,共9页
An experimental research is conducted on the heat transfer characteristics of a loop heat pipe(LHP)used in the"mainline"heat transfer mode for spacecraft platform thermal control.The heat from multiple instr... An experimental research is conducted on the heat transfer characteristics of a loop heat pipe(LHP)used in the"mainline"heat transfer mode for spacecraft platform thermal control.The heat from multiple instruments scattered in different locations is collected by thermal control techniques such as axially grooved heat pipes and then transmitted to the radiant surface for dissipation through the LHP in an unified way.The research contents include the start-up characteristics,the operational stability characteristics,the operational blocking characteristics,the continuous blocking characteristics,the heat transfer capability,the thermal resistance,and the dynamic response characteristics under the change of the heat sink temperature.The results show that the higher the auxiliary starting power is,the easier it is to start the LHP;the higher the input power of the thermoelectric cooler is,the more beneficial it is to speed up the stabilization of the vapor-liquid interface in the condenser;the higher the blocking power,the shorter the blocking time of the LHP;the LHP can be operated stably within the heat sink temperature alteration process;the heat transfer ability is higher than 500 W with a systematic thermal resistance of 0.037℃/W. 展开更多
关键词 LHP mainline HEAT TRANSFER MODE HEAT TRANSFER characteristics
Ethanol extract from Gynostemma pentaphyllum ameliorates dopaminergic neuronal cell death in transgenic mice expressing mutant A53T human alpha-synuclein 预览
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作者 Hyun Jin Park Ting Ting Zhao +4 位作者 Seung Hwan Kim Chong Kil Lee Bang Yeon Hwang Kyung Eun Lee Myung Koo Lee 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期361-368,共8页
Gynostemma(G.) pentaphyllum(Cucurbitaceae) contains various bioactive gypenosides. Ethanol extract from G. pentaphyllum(GP-EX) has been shown to have ameliorative effects on the death of dopaminergic neurons in animal... Gynostemma(G.) pentaphyllum(Cucurbitaceae) contains various bioactive gypenosides. Ethanol extract from G. pentaphyllum(GP-EX) has been shown to have ameliorative effects on the death of dopaminergic neurons in animal models of Parkinson’s disease(PD) induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-and 6-hydroxydopamine. PD patients exhibit multiple symptoms, so PD-related research should combine neurotoxin models with genetic models. In the present study, we investigated the ameliorative effects of GP-EX, including gypenosides, on the cell death of dopaminergic neurons in the midbrain of A53 T α-synuclein transgenic mouse models of PD(A53 T). Both GP-EX and gypenosides at 50 mg/kg per day were orally administered to the A53 T mice for 20 weeks.α-Synuclein-immunopositive cells and α-synuclein phosphorylation were increased in the midbrain of A53 T mice, which was reduced following treatment with GP-EX. Treatment with GP-EX modulated the reduced phosphorylation of tyrosine hydroxylase, extracellular signal-regulated kinase(ERK1/2), Bcl-2-associated death promoter(Bad) at Ser112, and c-Jun N-terminal kinase(JNK1/2) due to α-synuclein overexpression. In the A53 T group, GP-EX treatment prolonged the latency of the step-through passive avoidance test and shortened the transfer latency of the elevated plus maze test. Gypenosides treatment exhibited the effects and efficacy similar to those of GP-EX. Taken together, GP-EX, including gypenosides, has ameliorative effects on dopaminergic neuronal cell death due to the overexpression of α-synuclein by modulating ERK1/2, Bad at Ser112, and JNK1/2 signaling in the midbrain of A53 T mouse model of PD. Further studies are needed to investigate GP-EX as a treatment for neurodegenerative synucleinopathies, including PD. This study was approved by the Animal Ethics Committee of Chungbuk National University(approval No. CBNUA-956-16-01) on September 21, 2016. 展开更多
关键词 A53T α-synuclein genetic mice ERK1/2 GYNOSTEMMA pentaphyllum GYPENOSIDES Parkinson’s disease retention transfer LATENCY time
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Computer Multimedia Network File Transfer Security Protection System 预览
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作者 Chunwei Deng 《计算机科学与技术汇刊:中英文版》 2019年第1期10-13,共4页
With the rapid development of Internet technology and the rapid increase of multimedia information, people put forward higher requirements for the security, reliability, stability and efficiency of multimedia file tra... With the rapid development of Internet technology and the rapid increase of multimedia information, people put forward higher requirements for the security, reliability, stability and efficiency of multimedia file transmission. As far as the current network situation is concerned, there are various problems in network security, so how to ensure the safe transmission of files is a very important research topic. In order to improve the security effect of database information, we should also do a good job of classification and archiving storage. Multimedia files must be heavily compressed so that they can be efficiently transmitted over traditional data communication networks. The rapid development of computer networks has made people's lives more and more convenient. In the process of using computer networks, it is necessary to actively strengthen the security control of file transmission on computer networks. Take appropriate measures to avoid network file transmission security risks. 展开更多
关键词 MULTIMEDIA FILE TRANSFER COMPUTER NETWORK
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D-二聚体联合癌胚抗原在非小细胞肺癌远处转移诊断的应用 预览
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作者 孙亚楠 樊鹏鹏 梁晶晶 《临床研究》 2019年第10期24-26,共3页
目的探讨D-二聚体(D-Dimer)、癌胚抗原(CEA)、铁蛋白(Ferritin)及糖类抗原CA199联合应用在诊断非小细胞肺癌(NSCLC)远处转移的应用价值。方法将2017年4月-2018年6月于本院住院治疗的NSCLC确诊患者98例作为研究对象,其中经医学影像学及... 目的探讨D-二聚体(D-Dimer)、癌胚抗原(CEA)、铁蛋白(Ferritin)及糖类抗原CA199联合应用在诊断非小细胞肺癌(NSCLC)远处转移的应用价值。方法将2017年4月-2018年6月于本院住院治疗的NSCLC确诊患者98例作为研究对象,其中经医学影像学及病理学明确诊断骨或脑组织转移的46例患者定义为观察组,未明确诊断为骨或脑组织转移的52例患者定义为无转移组,并选择同期健康体检者48例为正常对照组。血清CEA、Ferritin及CA199均应用电化学发光法检测;血浆D-Dimer应用免疫比浊法检测;对比三组患者各指标表达差异,分析四指标联合应用诊断NSCLC远处转移的临床效能。结果未转移组和对照组D-Dimer、CEA、Ferritin及CA199表达均明显低于观察组(均P<0.01);当D-Dimer、CEA、CA199、Ferritin四项指标临界值分别为:120(pg/mL)、3.5(μg/L)、35.5(U/mL)、Ferritin[男>380(ng/mL)、女>160(ng/mL)]时,D-Dimer、CEA、CA199、Ferritin联合检测的敏感度95.65、特异性96.04%、准确度95.92%、AUC0.874均明显高于各单项检测结果(均P<0.05或P<0.01)。结论D-Dimer、CEA、CA199、Ferritin四项指标于NSCLC转移患者表达水平升高明显,四指标联合检测可明显提高NSCLC转移的诊断效能,更有助于临床疾病进展监测和治疗。 展开更多
关键词 非小细胞肺癌 D-二聚体 转移 癌胚抗原
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政策演进中的独立学院转设现状及其变革路径探析 预览
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作者 王凤华 《现代教育科学》 2019年第2期10-14,共5页
2008年2月22日教育部颁布《独立学院设置与管理办法》,该法令颁布后独立学院开始了转设发展之路,转设进程虽然缓慢,但每年都有一批独立学院转设成为独立设置的普通本科高校。本文结合相关数据,对独立学院的转设数量、转设地域分布、转... 2008年2月22日教育部颁布《独立学院设置与管理办法》,该法令颁布后独立学院开始了转设发展之路,转设进程虽然缓慢,但每年都有一批独立学院转设成为独立设置的普通本科高校。本文结合相关数据,对独立学院的转设数量、转设地域分布、转设后办学属性选择以及举办者进行了分析,对独立学院规范发展的政策制度设计与推进过程进行了梳理。随着民办教育新法新政的颁布和分类管理的实施,在新一轮高等教育利益格局变革中,独立学院应尽快明确发展道路,把握发展机遇。 展开更多
关键词 独立学院 转设 分类管理
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美沙酮维持治疗门诊转诊后漏服药受治者服药剂量增加及其影响因素
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作者 龚成 刘茵 +1 位作者 卢倩 凌莉 《中华疾病控制杂志》 CAS CSCD 北大核心 2019年第5期588-591,596共5页
目的分析美沙酮门诊间转诊后漏服受治者的剂量变化及其影响因素,为加强受治者转诊后服药剂量管理提供依据。方法收集广东省9家美沙酮维持治疗门诊自2008年1月~2016年12月所有受治者资料,选择其中未按时返回原门诊的转诊记录进行分析。... 目的分析美沙酮门诊间转诊后漏服受治者的剂量变化及其影响因素,为加强受治者转诊后服药剂量管理提供依据。方法收集广东省9家美沙酮维持治疗门诊自2008年1月~2016年12月所有受治者资料,选择其中未按时返回原门诊的转诊记录进行分析。收集转诊时间、转诊剂量等转诊信息、匹配受治者的服药信息及基本信息,以受治者的转诊后首次服药剂量与转诊期间服药剂量相比剂量是否增加为因变量,运用二水平的Logistic模型分析转诊后剂量增加的影响因素。结果本研究共纳入197名受治者合计840人次转诊记录进行分析,其中119(14.26%)人次在转诊后剂量增加,转诊期间美沙酮服药剂量低于60 ml/d(OR=2.88,95%CI:1.85~4.50,P<0.001),转诊天数越长(OR=1.02, 95%CI:1.01~1.03,P<0.001),累计转诊次数少(OR=0.97, 95%CI:0.95~0.99,P=0.004)的受治者越容易在转诊返回后提高美沙酮服用剂量。结论部分漏服药的转诊受治者在返回后首次服药会提高其剂量。各美沙酮门诊应加强对转诊受治者尤其是未按时返回的受治者的监管,对于受治者的剂量调整要求慎重考虑,减少剂量变化,提高美沙酮维持治疗的效果。 展开更多
关键词 美沙酮维持治疗 转诊 漏服药 剂量增加
Transfer function measurement for the SSRF SRF system 预览
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作者 Yang-Yang Xia Zhen-Tang Zhao +5 位作者 Yu-Bin Zhao Xiang Zheng Kai Xu Zhi-Gang Zhang Shen-Jie Zhao Qiang Chang 《核技术:英文版》 SCIE CAS CSCD 2019年第6期129-137,共9页
A digital transfer function measurement system has been embedded in the low-level radio frequency (LLRF) system of the storage ring of the Shanghai Synchrotron Radiation Facility. The measurement results indicate that... A digital transfer function measurement system has been embedded in the low-level radio frequency (LLRF) system of the storage ring of the Shanghai Synchrotron Radiation Facility. The measurement results indicate that the decreased control accuracy at high current is primarily owing to ripples from the high-voltage power supply, the transient beam loading effect, and the digital aliasing effect. The current LLRF algorithm is not able to suppress these disturbances. 展开更多
关键词 TRANSFER function RIPPLES of HVPS TRANSIENT BEAM LOADING effect
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Universally composable oblivious transfer from ideal lattice
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作者 Momeng LIU Yupu HU 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第4期879-906,共28页
As a fundamental cryptographic primitive, oblivious transfer (OT) is developed for the sake of efficient usability and combinational feasibility. However, most OT protocols are built upon some quantum non-immune crypt... As a fundamental cryptographic primitive, oblivious transfer (OT) is developed for the sake of efficient usability and combinational feasibility. However, most OT protocols are built upon some quantum non-immune cryptosystems by assuming the hardness of discrete logarithm or factoring problem, whose security will break down directly in the quantum setting. Therefore, as a subarea of postquantum cryptography, lattice-based cryptography is viewed as a promising alternative and cornerstone to support for building post-quantum protocols since it enjoys some attractive properties, such as provable security against quantum adversaries and lower asymptotic complexity. In this paper, we first build an efficient 1-out-of-2 OT protocol upon the hardness of ring learning with errors (RLWE) problem, which is at least as hard as some worst-case ideal lattice problems. We show that this 1-out-of-2 OT protocol can be universally composable and secure against static corruptions in the random oracle model. Then we extend it to a general case, i.e., 1-out-of-N OT with achieving the same level of security. Furthermore, on the basis of the above OT structure, we obtain two improved OT protocols using two improved lattice-based key exchange protocols (respectively relying on the RLWE problem and learning with errors (LWE) problem, and both achieving better efficiency by removing the Gaussian sampling for saving cost) as building blocks. To show that our proposed OT protocol indeed achieves comparable security and efficiency, we make a comparison with another two lattice-based OT protocols in the end of the paper. With concerning on the potential threat from quantum computing and expecting on the practical use of OT with high efficiency, an efficient post-quantum OT protocol is pressing needed. As shown in this paper, our proposed OT protocols may be considered as post-quantum OT candidates since they can both preserve provable security relying on lattice problems and enjoy practical efficiency. 展开更多
关键词 oblivious transfer universally COMPOSABILITY lattice-based CRYPTOGRAPHY LEARNING with ERRORS ring LEARNING with ERRORS RANDOM oracle model
Modeling of UAV path planning based on IMM under POMDP framework 预览
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作者 YANG Qiming ZHANG Jiandong SHI Guoqing 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第3期545-554,共10页
In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the PO... In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the POMDP framework. The elements of the POMDP model are analyzed and described. The state transfer law in the model can be described by the method of interactive multiple model (IMM) due to the diversity of the target motion law, which is used to switch the motion model to accommodate target maneuvers, and hence improving the tracking accuracy. The simulation results show that the model can achieve efficient planning for the UAV route, and effective tracking for the target. Furthermore, the path planned by this model is more reasonable and efficient than that by using the single state transition law. 展开更多
关键词 PARTIALLY OBSERVABLE Markov decision process (POMDP) interactive multiple model (IMM) FILTERING path planning target tracking state transfer law
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Effect of Flow Directions on Multiphase Flow Boiling Heat Transfer Enhanced by Suspending Particles in a Circulating Evaporation System 预览
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作者 Feng Jiang Teng Jiang +1 位作者 Guopeng Qi Xiulun Li 《天津大学学报:英文版》 EI CAS 2019年第3期201-213,共13页
A circulating fluidized bed evaporator(including down-flow,horizontal,and up-flow beds) was constructed to study the effect of flow directions on multiphase flow boiling heat transfer.A range of experimental investiga... A circulating fluidized bed evaporator(including down-flow,horizontal,and up-flow beds) was constructed to study the effect of flow directions on multiphase flow boiling heat transfer.A range of experimental investigations were carried out by varying amount of added particles(0-2%),circulation flow rate(2.15-5.16 m^3/h) and heat flux(8-16 kW/m^2).The comparison of heat transfer performance in different vertical heights of the horizontal bed was also discussed.Results reveal that the glass bead particle can enhance heat transfer compared with vapor-liquid two-phase flow for all beds.At a low heat flux(q = 8 kW/m),the heat-transfer-enhancing factor of the horizontal bed is obviously greater than those of the up-flow and down-flow beds.With the increase in the amount of added particles,the heat-transfer-enhancing factors of the up-flow and down-flow beds increase,whereas that of the horizontal bed initially increases and then decreases.However,at a high heat flux(q=16 kW/m),the heat-transfer-enhancing factors of the three beds show an increasing tendency with the increase in the amount of added particles and become closer than those at a low heat flux.For all beds,the heat-transfer-enhancing factor generally increases with the circulation flow rate but decreases with the increase in heat flux. 展开更多
关键词 Heat transfer enhancement CIRCULATING fluidized BED EVAPORATOR FLOW direction DOWN-FLOW BED UP-FLOW BED Horizontal BED
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农村承包地土地经营权出让相关法律问题探析——对《民法典各分编(草案)》第一百二十九条的思考 预览
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作者 周平 《安徽工业大学学报:社会科学版》 2019年第2期35-36,41,共3页
《民法典各分编(草案)》第一百二十九条规定,实行家庭承包的土地承包经营权人依照农村土地承包法的规定,有权出让土地经营权。这是我国首次从立法层面上明确了农户土地经营权可以出让。但与农村土地经营权出让相关法律问题必须明确,相... 《民法典各分编(草案)》第一百二十九条规定,实行家庭承包的土地承包经营权人依照农村土地承包法的规定,有权出让土地经营权。这是我国首次从立法层面上明确了农户土地经营权可以出让。但与农村土地经营权出让相关法律问题必须明确,相关法律规定有待统一修改,以构建农村土地经营权出让法律体系。 展开更多
关键词 土地经营权 出让 “三权”分置制度 法律体系
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An Analysis of Aphasia Phenomenon of Chinese Culture Among Non-English Majors 预览
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作者 居丽萍 《海外英语》 2019年第15期269-270,共2页
Social development in the new era is closely inseparable from good talents,the stress of whose cultivation,in turn,can guarantee solid development of whole society.This paper investigates and analyzes aphasia phenomen... Social development in the new era is closely inseparable from good talents,the stress of whose cultivation,in turn,can guarantee solid development of whole society.This paper investigates and analyzes aphasia phenomenon of Chinese culture among non-English majors to appeal for further inheritance and advancement by means of questionnaire survey plus vocabulary test,and proposes several ways in promoting high-end talent fostering. 展开更多
关键词 aphasia phenomenon of Chinese culture native language transfer high-end personnel training
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Luminescent properties of Ce3+,Er3+ co-doped La3Si6N11
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作者 Yuan Xue Ronghui Liu +5 位作者 Yuanhong Liu Huibing Xu Guantong Chen Xia Zhang Wei Gao Ze Jiang 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第3期248-252,共5页
In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce3+/Er3+ doped La3Si6N11 was designed and firstly prepared via conventional solid-state reac... In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce3+/Er3+ doped La3Si6N11 was designed and firstly prepared via conventional solid-state reactions. The structure and morphology of Ce3+/Er3+ doped La3Si6N11 were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Compared with Er3+ doped La3Si6N11,the emission intensity of the Ce3+, Er3+ co-doped phosphor can be increased more than 5 times.Meanwhile, the mechanism of energy transfer from Ce3+ to Er3+ is confirmed according to the excitation,emission spectra and decay lifetimes curve. Above results suggest that La3 Si6 N11:Ce3+,Er3+ is a promising near-infrared phosphor for blue pumped LEDs(light-emitting diodes). 展开更多
关键词 Solid state reaction Energy transfer NEAR-INFRARED PHOSPHOR La3Si6N11:Ce3+ ER3+ Rare earths
日本大学生汉语第三人称代词习得研究
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作者 《汉语国际传播研究》 2019年第1期1-6,共6页
本文以日本大学生汉语作文语料为基础,考察了日本大学生汉语第三人称代词的习得状况,发现日本大学生在汉语习得过程中存在第三人称代词回避使用现象.通过比较初级汉语教材中第三人称代词的使用状况,本文指出日本大学生汉语第三称代词回... 本文以日本大学生汉语作文语料为基础,考察了日本大学生汉语第三人称代词的习得状况,发现日本大学生在汉语习得过程中存在第三人称代词回避使用现象.通过比较初级汉语教材中第三人称代词的使用状况,本文指出日本大学生汉语第三称代词回避使用现象的存在,不仅是因为受到母语的干扰,还因为受到教材的影响. 展开更多
关键词 第三人称 回避使用 母语干扰 教材的影响 日本大学生
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