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Benchmarking Java against c and Fortran for scientific applications

cONcURRENcY AND cOMPUTATION-PRAcTIcE & EXPERIENcE 2003年第3-5期15卷 417-430页

作者： Bull, JM Smith, LA Ball, c Pottage, L Freeman, R Univ Edinburgh Edinburgh Parallel Comp Ctr Edinburgh EH9 3JZ Midlothian Scotland

Increasing interest is being shown in the use of Java for scientific applications. The Java Grande benchmark suite was designed with such applications primarily in mind. The perceived lack of performance of Java still deters many potential users, despite recent advances in just-in-time and adaptive compilers. There are, however, few benchmark results available comparing Java to more traditional languages such as c and Fortran. To address this issue, a subset of the Java Grande benchmarks has been re-written in c and Fortran allowing direct performance comparisons between the three languages. The performance of a range of Java execution environments, c and Fortran compilers have been tested across a number of platforms using the suite. These demonstrate that on some platforms (notable Intel Pentium) the performance gap is now quite small. copyright (c) 2003 John Wiley Sons, Ltd.

关键词： Java c Fortran performance benchmarking scientific applications

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SafeOSL: Ensuring memory safety of c via ownership-based intermediate language

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SOFTWARE-PRAcTIcE & EXPERIENcE 2022年第5期52卷 1114-1142页

作者： Yin, Xiaohua Huang, Zhiqiu Kan, Shuanglong Shen, Guohua chen, Zhe Liu, Yang Wang, Fei Nanjing Univ Aeronaut & Astronaut Coll Comp Sci & Technol Nanjing 211106 Peoples R China Collaborat Innovat Ctr Novel Software Technol & I Nanjing Peoples R China Minist Ind & Informat Technol Key Lab Safety Crit Software Nanjing Peoples R China TU Kaiserslautern Dept Comp Sci Kaiserslautern Germany Nanyang Technol Univ Sch Comp Sci & Engn Singapore Singapore Suzhou Univ Sci & Technol Sch Elect & Informat Engn Suzhou Peoples R China

The unsafe features of c make it a big challenge to ensure memory safety of c programs, and often lead to memory errors that can result in vulnerabilities. Various formal verification techniques for ensuring memory safety of c have been proposed. However, most of them either have a high overhead, such as state explosion problem in model checking, or have false positives, such as abstract interpretation. In this article, by innovatively borrowing ownership system from Rust, we propose a novel and sound static memory safety analysis approach, named SafeOSL. Its basic idea is an ownership-based intermediate language, called ownership system language (OSL), which captures the features of the ownership system in Rust. Ownership system specifies the relations among variables and memory locations, and maintains invariants that can ensure memory safety. The semantics of OSL is formalized in K-framework, which is a rewriting-logic based tool. c programs to be checked are first transformed into OSL programs and then detected by OSL semantics. Experimental results have demonstrated that SafeOSL is effective in detecting memory errors of c. Moreover, the translations and experiments indicate that the intermediate language OSL could be reused by other programming languages to detect memory errors.

关键词： c memory errors memory safety ownership system Rust

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Study on creep behavior and microstructure of a Fe-cr-Al-Nb-W ferrtic heat-resistant steel based on c, N and Al element control

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MATERIALS RESEARcH EXPRESS 2020年第5期7卷

作者： Zhang, Shanjun Shen, Junjie Kang, Hui Hu, Fuyong Tianjin Univ Technol Tianjin Key Lab Adv Mechatron Syst Design & Intel Sch Mech Engn Tianjin 300384 Peoples R China Tianjin Univ Technol Natl Demonstrat Ctr Expt Mech & Elect Engn Educ Tianjin 300384 Peoples R China

In this work, the effects of c, N, and Al on the microstructures and creep properties of Fe-cr-Al-Nb-W ferritic alloys were investigated through scanning electron microscopy, x-ray diffractometry, as well as uniaxial creep testing and hardness testing. The results demonstrated that the matrix of the Fe-cr-Al-Nb-W heat-resistant steel was ferrite, while the precipitation phases were Laves phases, M23c6 carbides and MX nitride phases. M23c6 and MX precipitated at grain interior, Laves phases precipitated at grain interior, grain boundary and around MX phases. c, N and Al affected microstructure and creep of heat-resistant steel. As the Al content increased or as N content decreased along with the c increase, the average diameter of the Laves phases, along with M23c6 and MX phase grain interior decrease. Moreover, the unit density increased and the phase spacing decreased, which led to the minimum creep rate decrease and creep rupture time increase. compared to M23c6, Laves and MX phases mainly affected the alloy creep strength. The decrease of Laves phase continuity coefficient (ratio of Laves phase particle spacing and size) on the grain boundary was conducive to the plasticity improvement of heat-resistant steel.

关键词： Laves phase ferrtic heat-resistant steel hardness creep strength c N and Al element control

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Finding an optimal core on a tree network with M/G/c/c state-dependent queues

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MATHEMATIcAL METHODS OF OPERATIONS RESEARcH 2019年第1期89卷 115-142页

作者： Moshtagh, Mehrdad Fathali, Jafar Smith, James MacGregor Mahdavi-Amiri, Nezam Shahrood Univ Technol Fac Math Sci Shahrood Iran Univ Massachusetts Dept Mech & Ind Engn Amherst MA 01003 USA Sharif Univ Technol Fac Math Sci Tehran Iran

We consider the stochastic queue core problem on a tree network. Our aim is to find an optimal path on a tree network subject to the average travel time of particles moving along the tree for service given by a server traversing along the optimal path. We assume that particles originating at a node on a tree network request their demands for service randomly and the server is modeled first by an M/M/1 and then by an M/G/1 queue using the FIFO discipline. We consider that all paths along which the particles travel are modeled with an M/G/c/c state-dependent queue with the particles being independent of each other having demands according to the Poisson distribution. Two algorithms are developed for computing the optimal path on a tree network along with the M/M/1 and the M/G/1 queues. The computational complexity of the algorithms and illustrative numerical results obtained by implementations of the algorithms in MATLAB software environment are given.

关键词： Facility location core of a tree network Stochastic queue core M G c c state-dependent queue Queueing theory

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Multi-walled carbon nanotubes induce transgenerational toxicity associated with activation of germline long non-coding RNA linc-7 in c. elegans

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cHEMOSPHERE 2022年 301卷 134687页

作者： Zhao, Yingyue Xu, Ruoran Hua, Xin Rui, Qi Wang, Dayong Nanjing Agr Univ Coll Life Sci Nanjing 210095 Peoples R China Southeast Univ Med Sch Nanjing 210009 Peoples R China

With the increase in application, multi-walled carbon nanotubes (MWcNTs) are potentially bioavailable to environmental organisms. However, the potential transgenerational effect of MWcNTs and underlying mechanisms remains still unclear. Here, we examined transgenerational MWcNT toxicity and the underlying mechanism mediated by germline long non-coding RNAs (lncRNAs) in caenorhabditis elegans. Exposure to 0.1-10 mu g/L MWcNT caused transgenerational toxicity reflected by endpoints of brood size and locomotion behavior. Meanwhile, among germline lncRNAs, expression of 5 lncRNAs were dysregulated by MWcNT exposure. Among these 5 dysregulated lncRNAs, only germline RNAi of linc-7 affected MWcNT toxicity. Increase in germline linc-7 expression was observed transgenerationally, and transgenerational MWcNT toxicity was prevented in linc-7 (RNAi) nematodes. Moreover, germline linc-7 controlled transgenerational MWcNT toxicity by activating downstream DAF-12, a transcriptional factor. Therefore, our data indicated the association between induction of transgenerational MWcNT toxicity and increase in germline linc-7 expression in organisms.

关键词： Multi-walled carbon nanotubes Germline linc-7 Transgenerational toxicity c elegans

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Hepatitis c virus may infect extrahepatic tissues in patients with hepatitis c

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World Journal of Gastroenterology 2000年第6期6卷 805-811页

作者： Fu Ming Yan An Shen chen Fei Hao Xi Ping Zhao chang Hai Gu Li Bin Zhao Dong Liang Yang Lian Jie Hao Department of Infectious Diseases the 161st Central Hospital of Chinese PLAWuhan 430010Hubei ProvinceChina Department of Infectious Diseases Southwest HospitalThird Military Medical UniversityChongqingChina Division of Clinical Immunology Tongji HospitalTongji Medical UniversityWuhanHubei ProvinceChina

AIM To explore the status of extrahepatichepatitis c virus(HcV)infection and replicationin hepatitis c patients,and its potentialimplication in HcV infection and *** By reverse-transcriptase poly-merase chain reaction(RT-PcR),in situhybridization(ISH)and immunohistochemistry,HcV RNA,HcV replicative intermediate(minus-strand of HcV RNA),and HcV antigens weredetected in 38 autopsy extrahepatic tissuespecimens(including 9 kidneys,9 hearts,9pancreas,5 intestines,2 adrenal glands,2spleens,1 lymph node,and 1 gallbladder)from 9hepatitis c patients,respectively;and thestatus of HcV replication in extrahepatic tissueswas *** By RT-PcR,all 9 patients werepositive for HcV RNA in kidney,heart,pancreas,and intestine,but only 6(66.7%)patients were positive for HcV *** RNA and HcV antigens weredetected in kidney,heart,pancreas,intestine,adrenal gland,lymph node,and gallbladder in 5(55.6%)and 6(66.7%)patients by ISH andimmunohistochemistry,*** RNA and HcV antigens were not detected in theseextrahepatic organs in 3(33.3%)patients,although their livers were positive for *** intermediate detected by RT-PcR wasconsistent with HcV RNA and HcV antigensdetected by ISH and immunohistochemistry(Kappa=0.42-0.75).HcV RNA and HcVantigens were detected in myocardial cells,epithelial cells of intestinal gladular,interstitialcells of kidney,epithelial cells of tubules andglomerulus,pancreas acinar cells and epithelialcells of pancreatic duct,epithelial cells ofmucous membrane sinus of gallbladder,cortexand medulla cells in adrenal gland,andmononuclear cells in lymph *** RNA wasalso detected in bile duct epithelial cells,sinusoidal cells,and mononuclear cells in livertissues by *** HcV can infect extrahepatictissues,and many various tissue cells maysupport HcV replication;extrahepatic HcVinfection and replication may be of'concomitantstate'in most of patients with hepatitis *** extrahepatic

关键词： hepatitis c virus hepatitis c antigens in situ hybridization immunohistochemistry RNA polymerase chain reaction antibodies monoclonal digoxigenin

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c and N turnover in structurally intact soils of different texture

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SOIL BIOLOGY & BIOcHEMISTRY 2003年第6期35卷 765-774页

作者： Thomsen, IK Schjonning, P Olesen, JE christensen, BT Danish Inst Agr Sci Res Ctr Foulum Dept Crop Physiol & Soil Sci DK-8830 Tjele Denmark

The turnover of native and applied c and N in undisturbed soil samples of different texture but similar mineralogical composition, origin and cropping history was evaluated at -10 kPa water potential. cores of structurally intact soil with 108, 224 and 337 g clay kg(-1). were horizontially sliced and N-15-labelled sheep faeces was placed between the two halves of the intact core. The cores together with unamended treatments were incubated in the dark at 20degreesc and the evolution Of cO2-c determined continuously for 177 d. Inorganic and microbial biomass N and N-15 were determined periodically. Net nitrification was less in soil amended with faeces compared with unamended soil. When adjusted for the NO3-N present in soil before faeces was applied, net nitrification became negative indicating that NO3-N had been immobilized or denitrified. The soil most rich in clay nitrified least N and N-15. The amounts of N retained in the microbial biomass in unamended soils increased with clay content. A maximum of 13% of the faeces N-15 was recovered in the microbial biomass in the amended Soils. cO2-c evolution increased with clay content in amended and unamended soils. cO2-c evolution from the most sandy soil was reduced due to a low content of potentially mineralizable native soil c whereas the rate constant of c mineralization rate peaked in this soil. When the pool of potentially mineralizable native soil c was assumed proportional to volumetric water content, the three soils contained similar proportions of potentially mineralizable native soil c but the rate constant of c mineralization remained highest in the soil with least clay. Thus although a similar availability of water in the three soils was ensured by their identical matric potential, the actual volume of water seemed to determine the proportion of total c that was potentially mineralizable. The proportion of mineralizable c in the faeces was simiiar in the three soils (70% of total c), again with a higher rat

关键词： N-15 c decomposition first order kinetics N texture

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Fecl3/c as an efficient catalyst for Ferrier rearrangement of 3,4,6-tri-O-Benzyl-D-glucal

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JOURNAL OF cARBOHYDRATE cHEMISTRY 2020年第5-6期39卷 232-249页

作者： Mei, Yuling Dong, Youxian Li, Juan Zhang, Bo Sun, Guosheng Zhou, Jiafen Si, Wenshuai Han, Yiwen Wu, Zhenliang Zhang, Jianbo East China Normal Univ Sch Chem & Mol Engn 500 Dongchuan Rd Shanghai 200241 Peoples R China

Fecl3/c was used as an efficient and convenient promoter for glycosylation through Ferrier-type rearrangement of 3,4,6-tri-O-benzyl-D-glucal, which is a relatively unreactive substrate for this type of reaction. The method was applicable to a wide range of alcohols, especially phenols. A series of 2,3-unsaturated-O-glucosides were prepared efficiently (47-92%) by this method under mild conditions.

关键词： Fecl3 c Ferrier rearrangement promoter glycosylation 346-tri-O-benzyl-D-glucal

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Fabrication of porous Sic nanostructured coatings on c/c composite by laser chemical vapor deposition for improving the thermal shock resistance

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cERAMIcS INTERNATIONAL 2022年第9期48卷 12450-12459页

作者： Wang, chongjie Guo, Bingjian Lu, Pengjian Xu, Qingfang Tu, Rong Kosinova, Marina Zhang, Song Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc 122 Luoshi Rd Wuhan 430070 Peoples R China Chem & Chem Engn Guangdong Lab Chaozhou Branch Chaozhou 521000 Peoples R China Wuhan Univ Technol Sch Mat Sci & Engn 122 Luoshi Rd Wuhan 430070 Peoples R China Zhejiang MTCN Technol Co Ltd 59 Luhui RdTaihu St Changxing 311103 Zhejiang Peoples R China Wuhan Tuocai Technol Co Ltd 147 Luoshi Rd Wuhan 430070 Peoples R China Russian Acad Sci Siberian Branch Nikolaev Inst Inorgan Chem 3 Acad Lavrerntiev Pr Novosibirsk 630090 Russia

Recently, fabricating one-dimensional (1D) nanomaterials on c/c composite has been recognized effective to improve the thermal shock resistance of the coated composites. However, the remaining metal catalyst in cVD process and the week bond of 1D nanomaterials with substrate limit the strengthening effect. Herein, laser chemical vapor deposition (LcVD) was proposed for fabricating porous Sic nanostructured coating on c/c composite without metal catalyst. The laser heating resulted in a temperature gradient between the top and bottom of the coating, providing an external driving force for the vertical growth of whiskers with side-branches, forming a porous network nanostructure. The porous nanostructure was beneficial to reduce cTE and effectively relieve thermal stress. After 10 times of thermal shock test from RT to 1723 K, the porous Sic nanostructured coating remained intact. This work provides a novel methodology to produce functional coating on c/c composite with outstanding thermal shock resistance.

关键词： Sic coating Laser chemical vapor deposition (LcVD) c c composite Porous nanostructure Thermal shock resistance

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Torsion and flexural-torsional coupled mechanical properties of different c/Sic torque tubes at room and elevated temperatures

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cERAMIcS INTERNATIONAL 2023年第10期49卷 14989-14996页

作者： Liu, Xiaochong Wang, Dongying Su, Yangzhi Guo, Hongqiang Li, Longbiao Liu, chidong Northwestern Polytech Univ Sch Mat Sci & Engn Xian 710072 Peoples R China Xian Xinyao Ceram Composite Mat Co Ltd Xian 710117 Peoples R China Nanjing Univ Aeronaut & Astronaut Coll Civil Aviat 29 Jiangjun Ave Nanjing 211106 Peoples R China

In this paper, the torsion and flexural-torsional coupled mechanical properties of different c/Sic torque tubes were investigated for the testing condition at room and elevated temperatures. Effects of fiber types, fiber preforms, and small hole during fabrication process on torsion mechanical properties were investigated. Flexural -torsional coupled mechanical tests for c/Sic torque tubes with different external diameter and wall thickness were conducted at room and elevated temperatures. The torsion and flexural moments and corresponding shear and flexural strength were obtained. The fracture surface and cracks propagation path were observed and analyzed. The torque and shear strength in T300TM-3k torque tube were much higher than those of T300TM-1k torque tube. Among 3D needled (3DN), 2D plain-woven [0 degrees /90 degrees] and [+/- 45 degrees] c/Sic torque tubes, the density, torque, and shear strength of 3DN-c/Sic torque tube were the highest. For the c/Sic torque tubes with small hole, the small hole not only increased the densification and uniformity (axial and radial) of the torque tube, but also has the potential to make the damage cracks more zigzag, which improved the fracture toughness of the torque tubes.

关键词： c Sic Torque tube Torsion Flexural -torsional Mechanical properties

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