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A New System to Evaluate Comprehensive Performance of Hard-Rock Tunnel Boring Machine Cutterheads

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 72-84页

作者： Ye Zhu Wei Sun junzhou Huo Zhichao Meng School of Mechanical and Engineering Dalian Jiaotong UniversityDalin 116000China School of Mechanical and Engineering Dalian University of TechnologyDalian 116000China

The accurate performance evaluation of a cutterhead is essential to improving cutterhead structure design and predicting project cost. Through extensive research, this paper evaluates the performance of a tunnel boring machine(TBM) cutterhead for cutting ability and slagging ability. This paper propose cutting efficiency, stability, and continuity of slagging as the evaluation indexes of comprehensive cutterhead performance. On the basis of research of true TBM engineering applications, this paper proposes a calculation method for each index. A slagging efficiency index with a ratio of the maximum di erence between the slagging amount and average slagging is established. And a slagging stability index with a ratio of the maximum slagging fluctuation and average slagging is presented. Meanwhile, a cutting efficiency index by the weighed average value of multistage rock fragmentation of a cutter’s specific energy is established. The Robbins and China Railway Construction Corporation(CRCC) cutterheads are evaluated. The results show that under the same thrust and torque, the slagging stability of the CRCC scheme is worse, but the slagging continuity of the CRCC scheme is better. The cutting ability index shows that the CRCC cutterhead is more efficient.

关键词： Evaluation of cutterhead Cutting ability Slagging ability Rock fragmentation load

Analysis of security protocols based on challenge-response

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Science in China(Series F) 2007年第2期50卷 137-153页

作者： LUO junzhou YANG Ming School of Computer Science and Engineering Southeast University Nanjing 210096 China

Security protocol is specified as the procedure of challenge-response, which uses applied cryptography to confirm the existence of other principals and fulfill some data negotiation such as session keys. Most of the existing analysis methods, which either adopt theorem proving techniques such as state exploration or logic reasoning techniques such as authentication logic, face the conflicts between analysis power and operability. To solve the problem, a new efficient method is proposed that provides SSM semantics-based definition of secrecy and authentication goals and applies authentication logic as fundamental analysis techniques, in which secrecy analysis is split into two parts： Explicit-lnformaUon-Leakage and Implicit-Information-Leakage, and correspondence analysis is concluded as the analysis of the existence relationship of Strands and the agreement of Strand pa- rameters. This new method owns both the power of the Strand Space Model and concision of authentication logic.

关键词： network security protocol analysis challenge-response Strand Space Model

Efficient Location-Aware Data Placement for Data-Intensive Applications in Geo-distributed Scientific Data Centers

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Tsinghua Science and Technology 2016年第5期21卷 471-481页

作者： Jinghui Zhang Jian Chen junzhou Luo Aibo Song School of Computer Science and Engineering Southeast University Nanjing 211189 China

Recent developments in cloud computing and big data have spurred the emergence of data-intensive applications for which massive scientific datasets are stored in globally distributed scientific data centers that have a high frequency of data access by scientists worldwide. Multiple associated data items distributed in different scientific data centers may be requested for one data processing task, and data placement decisions must respect the storage capacity limits of the scientific data centers. Therefore, the optimization of data access cost in the placement of data items in globally distributed scientific data centers has become an increasingly important *** data placement approaches for geo-distributed data items are insufficient because they either cannot cope with the cost incurred by the associated data access, or they overlook storage capacity limitations, which are a very practical constraint of scientific data centers. In this paper, inspired by applications in the field of high energy physics, we propose an integer-programming-based data placement model that addresses the above challenges as a Non-deterministic Polynomial-time（NP）-hard problem. In addition we use a Lagrangian relaxation based heuristics algorithm to obtain ideal data placement solutions. Our simulation results demonstrate that our algorithm is effective and significantly reduces overall data access cost.

关键词： data placement geo-distributed data center Lagrangian relaxation

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不同播期温光条件对籼稻产量和品质的影响

河南农业科学 2024年第2期53卷 17-27页

作者：樊一凡张艳艳王艺媚李俊周杜彦修孙红正彭廷赵全志张静河南农业大学农学院/河南省水稻生物学重点实验室/水稻河南省工程实验室河南郑州450046 贵州大学农学院贵州贵阳550025

为明确豫南稻区籼稻高产优质的温光条件,采用大田试验,以3个籼稻品种(兆优5431、中浙优8号和Y两优900)为试验材料,连续2 a研究不同播期[4月15日(T1)、4月30日(T2)、5月15日(T3)、5月30日(T4)和6月14日(T5)]下籼稻抽穗至成熟的积温、累... 详细信息

为明确豫南稻区籼稻高产优质的温光条件,采用大田试验,以3个籼稻品种(兆优5431、中浙优8号和Y两优900)为试验材料,连续2 a研究不同播期[4月15日(T1)、4月30日(T2)、5月15日(T3)、5月30日(T4)和6月14日(T5)]下籼稻抽穗至成熟的积温、累积光照时间、累积光照强度和产量及稻米加工品质、外观品质、营养品质、蒸煮品质,并进行不同播期下温光因子对籼稻稻米品质影响的冗余分析(RDA),通过温光因子的解释率找出影响豫南稻区稻米品质的关键环境因子。结果表明,随着播期的推迟,3个籼稻品种的产量、加工品质和营养品质均呈现先上升后下降的趋势,2 a均表现为T2处理产量最高,加工品质、外观品质和蒸煮品质较好,T5处理产量和品质表现最差。其中,2019年T2处理产量较T5处理提高129.4%,整精米率提高32.1%,垩白度、垩白粒率分别降低69.8%、69.9%,直链淀粉含量降低13.7%;2020年T2处理产量较T5处理提高271.0%,整精米率提高83.9%,垩白度、垩白粒率分别降低85.2%、77.6%,直链淀粉含量降低19.2%。稻米蛋白质含量则是T3处理最高,2019年和2020年T3处理较T5处理分别提高13.6%和20.0%。T2与T3处理间各品质指标差异均不显著。2 a产量均以T2处理下Y两优900最高,且其品质较好。3个品种抽穗到成熟阶段的积温、累积光照时间、累积光照强度均随着播期的推迟呈下降趋势,其中Y两优900的积温和累积光照时间下降幅度最大,兆优5431和中浙优8号下降幅度相当。RDA和解释率分析发现,水稻抽穗至成熟阶段的温光因子是造成稻米品质差异的主要环境因素,抽穗后10~20 d的累积光照时间是影响稻米品质的最主要生态因子。综上,豫南稻区籼稻以4月30日播种产量最高,且品质较好。

关键词：水稻播期温光条件产量品质

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Synthesis of photolabile dUTP analogues and their enzymatic incorporation for DNA labeling

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Science China Chemistry 2014年第2期57卷 322-328页

作者： WU junzhou WANG Jie TANG XinJing State Key Laboratory of Natural and Biomimetic Drugs the School of Pharmaceutical Sciences Peking University State key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences

Two new photolabile nucleotide analogues with furan-fused deoxyuridine were synthesized through Sonogashira *** enzymatic incorporation into DNA was evaluated with two DNA polymerases(Taq and Deep vent exo-)by polymerase chain reaction(PCR).Deep vent exo-recognized both nucleotides as substrates for primer extension,while Taq was much less *** irradiation of PCR products released the amino and carboxyl moieties of *** labeling with fluorescein isothiocyanate for a long DNA construct with F-dUnTP incorporation was successfully achieved.

关键词：核苷酸类似物 DNA标记不稳定酶促合成对光聚合酶链式反应 PCR产物

L183, a Quiescent Core?

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Chinese Journal of Astronomy and Astrophysics 2001年第3期1卷 250-256页

作者： Jian－junzhou Xing－WuZheng 等 UrumqiAstronomyObservatory ChineseAcademyofScienceXingjiang830011 DepartmentofAstronomy NanjingUnive

Some observed results of NH3 (1, 1) and (2,2) line emission in the starless dark cloud L183 are reported. Our observation suggests that the dense core of L183 has a size of ~ 0.16pc x0.1pc with a mass of ~ 12M. A velocity gradient of 4km s-1 pc-1 from the north to the south was detected. The velocity shift corresponds to a central mass of ~ 5M . If it is caused by rotation, the mass would be much less than the value above. This suggests that there may be more mass in the envelope of L183 than in the central region. The analysis of our data and the evidence in the literature about L183 indicate that it may be undergoing a process of collapsing to form a low-mass binary dense core.

关键词： ISM: clouds - Stars: formation - Stars: low-mass

播期和施氮量对中籼杂交稻群体质量、产量及氮素吸收利用的影响

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河南农业科学 2024年第4期53卷 37-46页

作者：张永泽王瑞刚王艺媚王梓豪李俊周杜彦修孙红正彭廷赵全志张静河南农业大学农学院/河南省水稻生物学重点实验室/水稻河南省工程实验室河南郑州450046 贵州大学农学院贵州贵阳550025

以中籼杂交稻Y两优900为试验材料,研究播期[4月15日(D1)、4月30日(D2)、5月15日(D3)、5月30日(D4)、6月14日(D5)]和施氮量[0 kg/hm^(2)(N0)、150 kg/hm^(2)(N150)和300 kg/hm^(2)(N300)]对中籼杂交稻群体质量、产量和氮素吸收利用的影响,以期探寻豫南稻区最适播期和施氮量。结果表明,播期和施氮量对中籼杂交稻产量的影响均达到显著水平,产量随播期推迟先升高后降低,以D2播期最高,D5播期最低,D2播期产量较D5播期提高126.42%。D2播期产量随着施氮量的增加而升高。整体来看,D2N300处理产量最高,其次是D1N300、D2N150处理。总叶面积指数和高效叶面积指数均随播期推迟先升高后降低,总叶面积指数和低效叶面积指数均随着施氮量的增加而增加。整体来看,总叶面积指数以D3N300处理最高,其次是D4N300、D2N300处理;高效叶面积指数以D3N300处理最高,其次是D4N300、D1N300处理;低效叶面积指数以D2N300处理最高,其次是D4N300、D3N300处理。粒数叶比和粒质量叶比均随着播期的推迟而降低,且随着施氮量的增加而降低。整体来看,粒数叶比以D1N0处理最高,其次是D2N0、D3N0处理;粒质量叶比以D1N0处理最高,其次是D3N0、D2N0处理。D1、D2、D3播期抽穗期和成熟期茎叶氮含量分别较D5播期增加12.81%、14.77%、13.02%和10.64%、25.08%、30.40%,且各个播期抽穗期和成熟期茎叶氮含量均随着施氮量增加而增加。抽穗期和成熟期穗氮含量表现为D1、D2播期显著高于D3、D4、D5播期,且各个播期N150、N300处理穗氮含量总体上均高于N0处理。氮素籽粒生产效率随着播期推迟先升高后下降,N150和N300处理均以D2播期最高,D5播期最低,且N150处理氮素籽粒生产效率明显高于N300处理。综上,播期和施氮量通过调节叶面积、粒叶比、植株氮含量和氮素籽粒生产效率影响产量,中籼杂交稻Y两优900在豫南地区丰产高效的适宜播种期是4月30日(D2),适宜施氮量为150~300 kg/hm^(2)。

关键词：中籼杂交稻播期施氮量群体质量产量氮素吸收利用

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Two New Monoterpene Diglycosides from Winchia calophylla ***

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Chinese Chemical Letters 2003年第10期14卷 1029-1032页

作者： WeiMingZHU BinGuiWANG WenYiKAN.G XmHONG junzhou XiaoJiangHAO DepartmentofChemistry YunnanNormalUniversityKunming650092 TheStateKeyLaboratoryofPhytochemistryandPlantResourcesinWestChina KunmingInstituteofBotanyChineseAcademyofSciences.Kunming650204

Two new monoterpene diglycosides, wincaloside A (1) and wincaloside B (2), along with loganin (3) were isolated from the stem barks of Winchia calophylla A. DC. The structures of 1 and 2 were established by spectrosco... 详细信息

关键词： Winchia calophylla Apocynaceae monoterpene diglycosides wincaloside.

An Active De-anonymizing Attack Against Tor Web Traffic

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Tsinghua Science and Technology 2017年第6期22卷 702-713页

作者： Ming Yang Xiaodan Gu Zhen Ling Changxin Yin junzhou Luo School of Computer Science and Engineering Southeast University Nanjing 211189 China

Tor is pervasively used to conceal target websites that users are visiting. A de-anonymization technique against Tor, referred to as website fingerprinting attack, aims to infer the websites accessed by Tor clients by passively analyzing the patterns of encrypted traffic at the Tor client side. However, HTTP pipeline and Tor circuit multiplexing techniques can affect the accuracy of the attack by mixing the traffic that carries web objects in a single TCP connection. In this paper, we propose a novel active website fingerprinting attack by identifying and delaying the HTTP requests at the first hop Tor node. Then, we can separate the traffic that carries distinct web objects to derive a more distinguishable traffic pattern. To fulfill this goal, two algorithms based on statistical analysis and objective function optimization are proposed to construct a general packet delay scheme. We evaluate our active attack against Tor in empirical experiments and obtain the highest accuracy of 98.64%, compared with 85.95% of passive attack. We also perform experiments in the open-world scenario. When the parameter k of k-NN classifier is set to 5, then we can obtain a true positive rate of 90.96% with a false positive rate of 3.9%.

关键词： traffic analysis active website fingerprinting anonymous communication Tor