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Experimental study on pore pressure in rock-soil slope during reservoir water level fluctuation

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science China(Technological sciences) 2005年第Z1期48卷 196-208页

作者： LIU Yuewu CHEN Huixin LIU Qingquan GONG Xin ZHANG Dawei LI Lianxiang division of Engineering science Institute of Mechanics Chinese Academy of Sciences Beijing 100080 Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing 100080 Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing 100080 Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing 100080 Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing 100080 Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing 100080

A test system was developed for measuring the pore pressure in porous media, and a new model was devised for the pore pressure testing in both saturated and unsaturated rock-soil. Laboratory experiments were carried out to determine the pore pressure during water level fluctuation. The variations of transient pore pressure vs. time at different locations of the simulated rock-soil system were acquired and processed, and meanwhile the deformation and failure of the model are observed. The experiment results show that whether the porous media are saturated or not, the transient pore pressure is mainly dependent on the water level fluctuation, and coupled with the variation of the stress field.

关键词： landslide, pore pressure, reservoir water level, rock-soil.

Developments in Processing of Functionally Gradient Metals and Metal–Ceramic Composites:A Review

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 825-838页

作者： T.P.D.Rajan B.C.Pai Materials science and Technology division CSIR-National Institute for Interdisciplinary Science and TechnologyIndustrial Estate PO

Functionally gradient/graded materials （FGMs）, an emerging new class of materials, are the outcome of the recent innovative concepts in materials technology. FGMs are in their early stages of evolution and expected to have a strong impact on the design and development of new components and structures with better performance. FGMs exhibit gradual transitions in the microstructure and/or the composition in a specific direction, the presence of which leads to variation in the functional performance within a part. The presence of gradual transitions in material composition in FGMs can reduce or eliminate the deleterious stress concentrations and result in a wide gradation of physical and/or chemical properties within the material. Functionally graded metal-ceramic composites are also getting the attention of the researchers. Among the fabrication routes for FGMs such as chemical vapour deposition, physical vapour deposition, the sol-gel technique, plasma spraying, molten metal infiltration, self propagating high temperature synthesis, spray forming, centrifugal casting, etc., the ones based on solidification route are preferred for FGMs because of their economics and capability to make large size products. The present paper discusses and compares various solidification processing tech- niques available for the fabrication of functionally gradient metals and metal-ceramic composites and lists their properties and possible applications. The other processing methods are briefly described.

关键词： Functionally gradient materials Solidification Aluminium Centrifugal casting Infiltration

A privacy preserving two-factor authentication protocol for the Bitcoin SPV nodes

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science China(Information sciences) 2020年第3期63卷 34-48页

作者： Lu ZHOU Chunpeng GE Chunhua SU division of Computer science University of Aizu College of Computer science and Technology Nanjing University of Aeronautics and Astronautics

In the Bitcoin network, the simplified payment verification protocol(SPV) enables a lightweight device such as a mobile phone to participate in the bitcoin network without needed to download and store the whole Bitcoin blocks. A Bitcoin SPV node initiates and verifies transactions of the Bitcoin network through the Bitcoin wallet software which is deployed on a resource constrained device such as a mobile phone. Thus, the security of the wallet is critical for the SPV nodes as it may affect the security of user’s cryptocurrencies. However, there are some concerns about the security flaws within the SPV nodes which could lead to significant economic losses. Most of these vulnerabilities can be resolved by employing a secure user authentication protocol. Over the years, researchers have engaged in designing a secure authentication protocol. However, most proposals have security flaws or performance issues. Recently, Park et al. proposed a two-party authenticated key exchange protocol for the mobile environment. They claimed that their protocol is not only secure against various attacks but also can be deployed efficiently. However, after a thorough security analysis, we find that the Park et al.’s protocol is vulnerable to user forgery attack, smart card stolen attack and unable to provide user anonymity. To enhance security, we proposed an efficient and secure user authentication protocol for the SPV nodes in the mobile environment which can fulfill all the security requirements and has provable security. Additionally, we provide performance analysis which shows our proposed protocol is efficient for the SPV nodes in the Bitcoin network.

关键词： SPV nodes secure authentication two-factor Bitcoin

DEVIATIONS FROM BULK MORPHOLOGIES IN THIN FILMS OF BLOCK COPOLYMER/ADDITIVE BINARY BLENDS

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Chinese Journal of Polymer science 2013年第9期31卷 1250-1259页

作者： Xin-yu Wei Wei-yin Gu Xiao-bo Shen Joseph Strzalka Zhang Jiang Thomas P. Russell Department of Polymer science and Engineering University of Massachusetts X-ray science division Argonne National Laboratory

Deviations from bulk morphologies in thin films of binary blends of alkyne-functionalized diblock copolymer poly（ethylene oxide）-bloek-poly（n-butyl methacrylate-random-propargyl methacrylate）（PEO-b-P（nBMA-r-PgMA）） and Rhodamine B azide are reported, where thermal click reaction between the two components leads to microphase separated morphologies. Both in the bulk and in thin films, increasing the azide loading ratio resulted in the u＇ansition from a lamellar microdomain morphology to a hexagonally packed cylindrical mireodomain morphology. However, in thin films the lamellae-cylinder transition was observed at a different azide loading ratio, which was determined by film thickness. As a result, significant deviations from the bulk morphology were observed. These results indicate that surface interactions and confined geometry can play an important role in dictating the morphology in thin films of BCP/additive binary blends.

关键词： Block copolymer Morphology Thin film.

Formal Approach to Workow Application Fragmentations Over Cloud Deployment Models

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Computers, Materials & Continua 2021年第6期67卷 3071-3088页

作者： Hyun Ahn Kwanghoon Pio Kim division of Computer science and Engineering Gyeonggi16227Korea

Workow management technologies have been dramatically improving their deployment architectures and systems along with the evolution and proliferation of cloud distributed computing ***,such cloud computing environments ought to be providing a suitable distributed computing paradigm to deploy very large-scale workow processes and applications with scalable on-demand *** this paper,we focus on the distribution paradigm and its deployment formalism for such very large-scale workow applications being deployed and enacted across the multiple and heterogeneous cloud computing *** propose a formal approach to vertically as well as horizontally fragment very large-scale workow processes and their applications and to deploy the workow process and application fragments over three types of cloud deployment models and *** concretize the formal approach,we rstly devise a series of operational situations fragmenting into cloud workow process and application components and deploying onto three different types of cloud deployment models and *** concrete approaches are called the deployment-driven fragmentation mechanism to be applied to such very large-scale workow process and applications as an implementing component for cloud workow management ***,we strongly believe that our approach with the fragmentation formalisms becomes a theoretical basis of designing and implementing very large-scale and maximally distributed workow processes and applications to be deployed on cloud deployment models and architectural computing environments as well.

关键词： Cloud workows cloud deployment model workow application fragmentations information control net

Surface-Induced Dissociation of Low Energy H_2^(+) Impact on a Carbon Surface: A Monte Carlo Simulation

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Communications in Theoretical Physics 2011年第2期55卷 315-320页

作者： Shakir Ullah A.H.Dogar A.Qayyum Physics division Pakistan Institute of Nuclear Science and Technology

A Monte Carlo simulation based on the classical binary collision approximation is performed to investigate the interaction of W2 ions with the carbon target. The incident H2^＋ ion is characterized by its translational energy, eigenenergy and population of the vibrational state, and orientation of the ion with respect to the target surface. It is shown that experimentally determined energy resolved mass spectrum of H＋ can be nicely reproduced with the help of the proposed model. These simulations predict that translational to vibrational （T → V） energy transfer efficiency increases nonlinearly with translational energy of the incident ion. T → V energy transfer efficiency along with the initial vibrational energy of the incident H＋ ion found to play an important role in dissociation. Our simulations also show that the fraction of absorbed, reflected, and dissociated ions depends on the translational energy. The average vibrational energy of reflected H＋ increases with its initial translational energy. Moreover, average number of collisions required for dissociation varies inversely with the initial translational energy of the H2^＋.

关键词： ion-surface collisions surface-induced dissociation hydrogen molecular ions Monte Carlo simulation

Excessive portal flow causes graft failure in extremely small-for-size liver transplantation in pigs

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World Journal of Gastroenterology 2005年第44期11卷 6954-6959页

作者： Hong-Sheng Wang Nobuhiro Ohkohchi Yoshitaka Enomoto Masahiro Usuda Shigehito Miyagi Takeshi Asakura Hiroo Masuoka Takashi Aiso Keisuke Fukushima Tomohiro Narita Hideyuki Yamaya Atsushi Nakamura Satoshi Sekiguchi Naoki Kawagishi Akira Sato Susumu Satomi division of Advanced Surgical science and Technology Department of Surgery

AIM： To evaluate the effects of a portocaval shunt on the decrease of excessive portal flow for the prevention of sinusoidal microcirculatory injury in extremely smallfor-size liver transplantation in pigs. METHODS： The right lateral lobe of pigs, i.e. the 25% of the liver, was transplanted orthotopically. The pigs were divided into two groups： graft without portocaval shunt （n = 11） and graft with portocaval shunt （n = 11）. Survival rate, portal flow, hepatic arterial flow, and histological findings were investigated. RESULTS： In the group without portocaval shunt, all pigs except one died of liver dysfunction within 24 h afcer transplantation. In the group with portocaval shunt, eight pigs survived for more than 4 d. The portal flow volumes before and after transplantation in the group without portocaval shunt were 118.2±26.9 mL/min/100 g liver tissue and 270.5±72.9 ml./min/100 g liver tissue, respectively. On the other hand, in the group with portocaval shunt, those volumes were 124.2±27.8 ml./ min/100 g liver tissue and 42.7±32.3 mL/min/100 g liver tissue, respectively （P〈0.01）. As for histological findings in the group without portocaval shunt, destruction of the sinusoidal lining and bleeding in the peri-portal areas were observed afl：er reperfusion, but these findings were not recognized in the group with portocaval shunt. CONCLUSION： These results suggest that excessive portal flow is attributed to post transplant liver dysfunction after extreme small-for-size liver transplantation caused by sinusoidal microcirculatory injury.

关键词： Hyperperfusion syndrome Liver regeneration Portocaval shunt Postoperative liver dysfunction Sinusoidal microcirculatory injury Small-for-size liver transplantation

Population structure and reproductive biology of the mysid Nanomysis siamensis(Crustacea:Mysida)in Songkhla Lagoon system,southern Thailand

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Journal of Oceanology and Limnology 2021年第3期39卷 997-1009页

作者： Rofiza YOLANDA Vachira LHEKNIM division of Biological science Faculty of SciencePrince of Songkla UniversitySongkhla 90112Thailand

Songkhla Lagoon in southern Thailand is a large lagoon with brackish water where the mysid Nanomysis siamensis *** has long been the dominant mysid species in this ***,nothing is known about the biology and ecology of *** for the first time,we provide information about its demographic structure and reproductive biology in the Songkhla Lagoon *** conducted monthly sampling from June 2017 to June 2018 at five stations in Thale Sap and seven stations in Thale Sap *** were classified into six *** monthly mean density ranged 8.44-807.33 inds./100 m^(2) in Thale Sap and 8.81-434.44 inds./100 m^(2) in Thale Sap *** peak occurrence of this species was in May 2018 in Thale *** population composition was as follows:juvenile 10.13%,immature males 13.45%,immature females 10.54%,mature males 26.19%,mature females 21.63%and ovigerous females 18.05%.The proportion of ovigerous females was statistically significant and brooding females in the nauplioid stage were more dominant than embryonic phase and post-nauplioid *** size varied from 1 to 17,the embryo diameter ranging from 0.2 to 0.4 mm and the lengths of the larvae ranged from 0.5 to 1.0 *** was a positive correlation between brood size and brood length with ovigerous female body ***,mature males were predominant over the five population composition types,and reproduction in *** was observed every month.

关键词： brackish water reproductive trait Thale Sap Thale Sap Songkhla

Potential application of high pressure carbon dioxide in treated wastewater and water disinfection:Recent overview and further trends

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Journal of Environmental sciences 2015年第10期27卷 38-47页

作者： Huy Thanh Vo Tsuyoshi Imai Truc Thanh Ho Thanh-Loc Thi Dang Son Anh Hoang division of Urban Infrastructural Engineering Mien trung University of Civil Engineering division of Environmental science and Engineering Yamaguchi University

Recently emerging disadvantages in conventional disinfection have heightened the need for finding a new solution. Developments in the use of high pressure carbon dioxide for food preservation and sterilization have led to a renewed interest in its applicability in wastewater treatment and water disinfection. Pressurized CO2 is one of the most investigated methods of antibacterial treatment and has been used extensively for decades to inhibit pathogens in dried food and liquid products. This study reviews the literature concerning the utility of CO2 as a disinfecting agent, and the pathogen inactivation mechanism of CO2 treatment is evaluated based on all available research. In this paper, it will be argued that the successful application and high effectiveness of CO2 treatment in liquid foods open a potential opportunity for its use in wastewater treatment and water disinfection. The findings from models with different operating conditions（pressure, temperature, microorganism, water content, media …） suggest that most microorganisms are successfully inhibited under CO2 treatment. It will also be shown that the bacterial deaths under CO2 treatment can be explained by many different ***, the findings in this study can help to address the recently emerging problems in water disinfection, such as disinfection by-products（resulting from chlorination or ozone treatment）.

关键词： High pressure CO2 Inactivation effect Inactivation mechanism