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Frontiers of Medicine 2013年第4期7卷 520-522页

作者： Eric c.h.Lai Department of Surgery Pamela Youde Nethersole Eastern HospitalChai WanHong KongChina

I read with great interest the consensus and guideline of laparoscopic hepatectomy,which was originated from the experts in china[1].This is a significant step forward in minimally invasive liver *** development of minimally invasive liver surgery over the last 2 decades has a great impact on the surgical practice in china,and the other parts of the *** potential advantages of laparoscopic hepatectomy are those of minimal access surgery(Table 1).

关键词： Surgery hepatectomy surgery

Stark-chirped Rapid Adiabatic Passage in Presence of Dissipation for Quantum computation

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communications in Theoretical Physics 2014年第2期61卷 235-240页

作者：石轩 c.h.Oh 韦联福 Quantum Optoelectronics Laboratory School of Physics and Technology Southwest Jiaotong University centre for Quantum Technologies and Department of Physics National University of Singapore State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Science and Engineering Sun Yet-sen University

Stark-chirped rapid adiabatic passage(ScRAP) is an important technique used for coherent quantum controls. In this paper we investigate how the practically-existing dissipation of the system influences on the efficiency of the passage, and thus the fidelities of the ScRAP-based quantum gates. With flux-biased Josephson qubits as a specifical example, our results show clearly that the efficiency of the logic gates implemented by ScRAP are robust against the weak dissipation. The influence due to the non-adiabtic transitions between the adiabatic passages is comparatively significantly small. Therefore, the ScRAP-based logic gates should be feasible for the realistic physical systems with noises.

关键词： adiabatic passage dissipation quantum computation

A novel mathematical morphology based algorithm for shoreline extraction from satellite images

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Geo-Spatial Information Science 2017年第4期20卷 345-352页

作者： c.A.Rishikeshan h.Ramesh National Institute of Technology Karnataka Surathkal India

Shoreline extraction is fundamental and inevitable for several *** the precise spatial location of the shoreline is ***,the need for using remote sensing data to accomplish the complex task of automatic extraction of features,such as shoreline,has considerably *** feature extraction can drastically minimize the time and cost of data acquisition and database *** and fast approaches are essential to monitor coastline retreat and update shoreline ***,we present a flexible mathematical morphology-driven approach for shoreline extraction algorithm from satellite *** salient features of this work are the preservation of actual size and shape of the shorelines,run-time structuring element definition,semi-automation,faster processing,and single band *** proposed approach is tested with various sensor-driven images with low to high *** of the developed methodology has been assessed with manually prepared ground truths of the study area and compared with an existing shoreline classification *** proposed approach is found successful in shoreline extraction from the wide variety of satellite images based on the results drawn from visual and quantitative assessments.

关键词： Feature extraction shoreline detection satellite image processing remote sensing mathematical morphology

A novel twice-interpolation finite element method for solid mechanics problems

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Acta Mechanica Sinica 2010年第2期26卷 265-278页

作者： c. Zheng S. c. Wu X. h. Tang J. h. Zhang State Key Laboratory of hydraulics and Mountain River Engineering Sichuan University 610065 Chengdu China State Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology 430074 Wuhan China Department of Mechanical Engineering Centre for Advanced Computations in Engineering Science (ACES)National University of Singapore Singapore 117576 Singapore

Formulation and numerical evaluation of a novel twice-interpolation finite element method （TFEM） is presented for solid mechanics problems. In this method, the trial function for Galerkin weak form is constructed through two stages of consecutive interpolation. The primary interpolation follows exactly the same procedure of standard FEM and is further reproduced according to both nodal values and averaged nodal gradients obtained from primary interpolation. The trial functions thus constructed have continuous nodal gradients and contain higher order polynomial without increasing total freedoms. Several benchmark examples and a real dam problem are used to examine the TFEM in terms of accuracy and convergence. compared with standard FEM, TFEM can achieve significantly better accuracy and higher convergence rate, and the continuous nodal stress can be obtained without any smoothing operation. It is also found that TFEM is insensitive to the quality of the elemental mesh. In addition, the present TFEM can treat the incompressible material without any modification.

关键词： Twice-interpolation finite element method·Stress smoothing Volumetric locking Mesh distortion

A novel mesh-free poly-cell Galerkin method

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Acta Mechanica Sinica 2009年第4期25卷 517-527页

作者： c. Zheng X. h. Tang J. h. Zhang S. c. Wu State Key Laboratory of hydraulics and Mountain River Engineering Sichuan University State Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology centre for Advanced computations in Engineering Science (AcES) Department of Mechanical EngineeringNational University of Singapore

A novel numerical method is explored and named as mesh-free poly-cell Galerkin method. An improved moving least-square （MLS） scheme is presented, which can avoid the matrix inversion in standard MLS and can be used to construct shape functions possessing delta Kronecher property. A new type of local support is introduced to ensure the alignment of integral domains with the cells of the back-ground mesh, which will reduce the difficult in integration. An intensive numerical study is conducted to test the accuracy of the present method. It is observed that solutions with good accuracy can be obtained with the present method.

关键词： MPG cO-MSL Mesh-free Meshless Voronoi diagram

Photo-induced Synthesis and characterization of Poly(methyl methacrylate) Grafted Sodium Salt of Partially carboxymethylated Guar Gum

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chinese Journal of Polymer Science 2014年第12期32卷 1690-1703页

作者： J.h.Trivedi M.D.Thaker h.c.Trivedi P.G. Department of chemistry Sardar Patel University

Photo-induced graft copolymerization of methyl methacrylate（MMA） onto sodium salt of partially carboxymethylated guar gum（Na-PcMGG, DS = 0.291） was carried out in an aqueous medium using ceric ammonium nitrate（cAN） as photoinitiator to synthesize a novel graft copolymer, Na-PcMGG-g-PMMA, which may find its potential application as a metal adsorbent. The influences of synthesis variables such as concentrations of photoinitiator（cAN）, nitric acid and monomer（MMA） as well as reaction time, temperature and amount of substrate on the grafting yields were studied and the reaction conditions for optimum photo-grafting were evaluated. At optimum concentration, the maximum values of the grafting yields achieved were G = 271.61% and GE = 63.89%. The experimental results were found to be in very good agreement with the proposed kinetic scheme. The photo-graft copolymerization of MMA onto Na-PcMGG（ DS = 0.291） was also carried out in the presence and absence of ultraviolet radiation for studying the efficiency of the photoinitiator. The influence of carboxymethyl groups introduced onto the guar gum molecules with regard to its behavior towards ultra-violet radiation induced grafting with MMA was also investigated. Photo-grafting process was confirmed and the products were characterized with the help of the spectroscopic（1h-NMR and FTIR） and SEM techniques.

关键词： Photo-induced grafting Methyl methacrylate Sodium salt of partially carboxymethylated guar gum Optimum reaction conditions characterization.

Longwall top coal caving design for thick coal seam in very poor strength surrounding strata

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International Journal of coal Science & Technology 2021年第4期8卷 641-658页

作者： h.Jangara c.Atilla Ozturk Mining Engineering Department Faculty of MinesIstanbul Technical UniversityIstanbulTurkey

Alpu lignite field is an important coal deposit with nearly 2 billion tons of coal resources located in the middle of *** mine deposit consists of three main *** thickness of two of them vary from 4 to 30 *** surrounding rock mass is very poor in terms of *** high clay content and weak rock mass make mechanized mining *** this research,applicability of the longwall top coal caving method was *** very weak strength behavior of the coal and the surrounding strata increases the importance of research in the mine site in terms of ground *** aim is to design the mechanized longwall mine based on ground control *** of all,classification of the roof,coal,inter-burden,and floor strata were classified based on geotechnical ***,cavability index,shield,and floor bearing capacity were *** methods were applied to understand the limitations of a mechanized system that is very critical due to the very low strength *** to the main results,roof strata was classified as immediately caving while mining height was calculated as 5-6 ***,the relations among geotechnical characterizations of roof and floor strata,cutting and caving heights,and required shield capacity were presented based on analytical and numerical *** proposed approach can be used as a ground control method for the applicability as well as the limitations of mechanized longwall mining design in weak strata conditions.

关键词： coal Geotechnics Ground control Longwall mining Numerical methods

cO_2 laser-micro plasma arc hybrid welding for galvanized steel sheets

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Transactions of Nonferrous Metals Society of china 2011年第A01期21卷 47-53页

作者： c.h.KIM Y.N.AhN J.h.KIM Advance Welding & Joining Research Group Korea Institute of Industrial Technology Incheon 406-840 South Korea

A laser lap welding process for zinc-coated steel has a well-known unsolved problem-porosity formation. The boiling temperature of coated zinc is lower than the melting temperature of the base metal, which is steel. In the autogenous laser welding, the zinc vapor generates from the lapped surfaces expels the molten pool and the expulsion causes numerous weld defects, such as spatters and blow holes on the weld surface and porosity inside the welds. The laser-arc hybrid welding was suggested as an alternative method for the laser lap welding because the arc can preheat or post-beat the weldment according to the arrangement of the laser beam and the arc. cO2 laser-micro plasma hybrid welding was applied to the lap welding of zinc-coated steel with zero-gap. The relationships among the weld quality and process parameters of the laser-arc arrangement, and the laser-arc interspacing distance and arc current were investigated using a full-factorial experimental design. The effect of laser-arc arrangement is dominant because the leading plasma arc partially melts the upper steel sheets and vaporizes or oxidizes the coated zinc on the lapped surfaces. compared with the result from the laser-TIG hybrid welding, the heat input from arc can be reduced by 40%.

关键词： galvanized steel cO2 laser micro plasma hybrid welding

Analysis of electron energy distribution function in a magnetically filtered complex plasma

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chinese Physics B 2013年第4期22卷 324-329页

作者： M K Deka h Bailung N c Adhikary Physical Sciences Division Institute of Advanced Study in Science and Technology Vigyan Path Paschim Boragaon Garchuk Guwahati-781035 Assam India

The electron energy distribution function （EEDF） for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ～ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter.

关键词： dusty plasma magnetic filter electron energy distribution function

Laser additive manufacturing of biodegradable Mg-based alloys for biomedical applications: A review

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Journal of Magnesium and Alloys 2022年第4期10卷 915-937页

作者： c.L.Wu W.J.Xie h.c.Man Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Metallic implants are widely used in internal fixation of bone fracture in surgical *** are mainly used for providing mechanical support and stability during bone reunion,which usually takes a few months to *** implants made of stainless steels,Ti-based alloys and cocrMo alloys have been widely used for orthopedic reconstruction due to their high strength and high corrosion *** metallic implants will remain permanently inside the body after implantation,and a second surgery after bone healing is needed because the long-term presence of implant will lead to various *** implant removal surgery not only incurs expenditure,but also risk and psychological *** a consequence,studies on the development of biodegradable implants,which would degrade and disappear in vivo after bone reunion is completed,have drawn researchers’*** this connection,Mg-based alloys have shown great potentials as promising implant materials mainly due to their low density,inherent biocompatibility,biodegradability and mechanical properties close to those of ***,the high degradation rate of Mg-based implants in vivo is the biggest hurdle to *** from materials selection,a fixation implant is ideally tailor-made in size and shape for an individual case,for best surgical ***,laser additive manufacturing(LAM),with the advent of sophisticated laser systems and software,is an ideal process to solve these *** this paper,we reviewed the progress in LAM of biodegradable Mg-based alloys for biomedical *** effect of powder properties and laser processing parameter on the formability and quality was thoroughly *** microstructure,phase constituents and metallurgical defects formed in the LAMed samples were *** mechanical properties,corrosion resistance,biocompatibility and antibacterial properties of the LAMed samples were summarized and compared with samples fabricated by

关键词： Laser additive manufacturing Magnesium alloys Implant Biomedical applications Mechanical properties Biodegradability