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Study on the risk factors of lymphatic metastasis and the indications of less invasive operations in early gastric cancer

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World Journal of Gastroenterology 2000年第4期6卷 553-556页

作者： Jiang bj Sun RX Lin H Gao YF Shanghai Jing An Cent Hosp Dept Gen Surg Shanghai 200040 Peoples R China

The principle of surgical treatment for gastric cancer is the radical resectioning although the suitable resecting range for different cases of gastric cancer is still being argued upon[1-9]. However, the diagnostic accuracy of early gastric cancer (EGC) without lymphatic metastasis has obviously improved with an improvement in the diagnostic technique and due to the accumulation of knowledge on the biological profiles of EG C[10-17]. The D2 lymph node excision was used as a regular operation to treat the EGC previously. But the concept for the EGC without lymphatic metastasis has gradually changed and the less invasive resections has been applied in some cases[18-20]. This study aimed at investigating the risk factors of lymphatic metastasis in EGC in order to find out the proofs for the suitable indications for less invasive operations such as endoscopic mucosal resectioning (EMR), laparoscopic and laparotomic resectioning.

关键词： stomach neoplasms/diagnosis neoplasm metastasis precancerous conditions risk factors surgery/operative lymphatic metastasis lymph node excision

Computation of Two-Phase Biomembranes with Phase Dependent Material Parameters Using Surface Finite Elements

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Communications in Computational Physics 2013年第2期13卷 325-360页

作者： Charles M.Elliott björn Stinner Mathematics Institute and Centre for Scientific Computing University of WarwickCoventry CV47ALUnited Kingdom

The shapes of vesicles formed by lipid bilayers with phase separation are governed by a bending energy with phase dependent material parameters together with a line energy associatedwith the phase *** present a numericalmethod to approximate solutions to the Euler-Lagrange equations featuring triangulated surfaces,isoparametric quadratic surface finite elements and the phase field approach for the phase ***,the method involves an iterative solution scheme that is based on a relaxation dynamics coupling a geometric evolution equation for the membrane surface with a surface Allen-Cahn *** and grid adaptivity are discussed,and in various simulations the influence of several physical parameters is investigated.

关键词： Biomembrane surface finite elements relaxation dynamics

Use of Standard Operating Procedures for Supporting Cross-Organizational Emergency Management: Challenges and Opportunities Identified from a Tabletop Exercise

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International Journal of Disaster Risk Science 2024年第5期15卷 673-687页

作者： Kristine Steen-Tveit bj?rn Erik Munkvold Kjetil Rustenberg Department of Information Systems Centre for Integrated Emergency ManagementUniversity of Agder

This study investigated the crucial role of formulating and applying standard operating procedures(SOPs) in the context of emergency planning and response. The effective application of SOPs during operations is essential in order to address challenges that surpass individual organizational capacities. A specific focus on fostering efficient information sharing and executing specified actions maximizes the prospect of success. To explore the collective functionality of SOPs across organizations, we conducted a comprehensive tabletop exercise involving 10 organizations spanning tactical, operational,and strategic levels. Our analysis identified six key challenges, primarily related to the structures for information sharing,communication pathways, and the complex integration and application of common SOPs within these diverse organizational contexts. This research contributes insights into the use of SOPs in large-scale, cross-organizational scenarios.

关键词： Cross-organizational emergency management Standard operating procedures Tabletop exercise Team situational awareness

Optimized design and integration of energy storage in Solar-Assisted Ground-Source Heat Pump systems

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Building Simulation 2023年第10期16卷 1933-1948页

作者： maria Ferrara Enrico Fabrizio Department of Energy Politecnico di TorinoTurin10121Italy

The integrated use of multiple renewable energy sources to increase the efficiency of heat pump systems,such as in Solar Assisted Geothermal Heat Pumps(SAGHP),may lead to significant benefits in terms of increased efficiency and overall system performance especially in extreme climate contexts,but requires careful integrated optimization of the different system *** particular,thermal storages take a fundamental role in optimizing the integration of renewable energy sources and the system *** work investigates the potential design optimization of a SAGHP system in a mountain site by exploring many different alternatives to optimize the mutual relationship between the solar field,the geothermal field and the water thermal *** is done through an original simulation-based multi-objective optimization framework considering energy efficiency and economic feasibility,which allows appraising the impact of the different design alternatives on the overall system performance and on the dynamics of the different system *** identify a set of optimized system configurations that optimize the integrated exploitation of the different thermal sources showing a potential increase of the overall system performance leading to 34%lower global cost compared to the initial *** robustness of the optimal design solutions is reported with respect to the current context of high economic uncertainty.

关键词： thermal storage geothermal energy heat pumps building simulation artificial intelligence cost optimization energy flexibility

Construction of Conservative Numerical Fluxes for the Entropy Split Method

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Communications on Applied Mathematics and Computation 2023年第2期5卷 653-678页

作者： björn Sjögreen H.C.Yee Multid Analyses AB GothenburgSweden NASA Ames Research Center Moffett FieldCA 94035USA

The entropy split method is based on the physical entropies of the thermally perfect gas Euler *** Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in J Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et *** J Comp Phys 162:33-81,2000).Sj?green and Yee(J Sci Comput)recently proved that the entropy split method is entropy conservative and ***-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy *** current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux *** to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split ***,the Tadmor entropy conservative(EC)method(Tadmor in Acta Numerica 12:451-512,2003)of the same order requires more operations count than the new *** the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et *** J Comput Phys 150:199-238,1999,J Comp Phys 162:3381,2000;Yee and Sj?green in J Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow *** of the ICOSAHOM09,June 22-26,Trondheim,Norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock ***-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches.

关键词： Finite-difference method Entropy conservation Entropy splitting Shock capturing

NONEXISTENCE OF PSEUDO-SELF-SIMILAR SOLUTIONS TO INCOMPRESSIBLE EULER EQUATIONS

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Acta Mathematica Scientia 2011年第6期31卷 2305-2312页

作者： maria Schonbek Department of Mathematics University of California

In this paper we study a generalization of self-similar solutions. We show that just as for the solutions to the Navier-Stokes equations these supposedly singular solution reduce to the zero solution.

关键词： Euler equations pseudo-self-similar solutions

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Hydro Power in Norway- Development, Political Priorities and Public Opinion ——Lessons learned through mora than 100 years of developments

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Small Hydro Power News 2005年第81期22卷 20-22页

作者： bjφm Wold Norwegian Water Resources and Energy Directorate P.O.Box 5091MJ. N-0301 OSLO Norway.

The production of hydro power from its natural water resources has come to mean more to Norway than to possibly any other country in world. The right to utilize the falling water in the rivers belonged to whoever owned the adjacent ground. The acquisition of water rights is not allowed without a license from the government. Any development is also dependent on a governmental licence. Important conditions such as return of the property to the government without any compensation after 60 years, compulsory delivery of power at production cost and license fees to the local municipalities have been important incentives for the public and political acceptance of hydro power development in Norway during a long period of economic development. Today, Norway is a rich and materially well developed country, and there is no longer any acceptance for further hydro power development. Some of the remaining potential will be utilized for small-scale local developments, but most of it will be incorporated in governmental conservation plans.

关键词： Hydro power licensing public acceptance

Evolution of the ring-like vortices and spike structure in transitional boundary layers

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 514-520页

作者： OLIVEIRA maria Department of Mathematics University of Texas at Arlington Arlington Texas 76010 USA

At the late stage of transitional boundary layers, the nonlinear evolution of the ring-like vortices and spike structures and their effects on the surrounding flow were studied by means of direct numerical simulation with high order accuracy. A spatial transition of the flat-plate boundary layers in the compressible flow was conducted. Detailed numerical results with high resolution clearly represented the typical vortex structures, such as ring-like vortices and so on, and induced ejection and sweep events. It was verified that the formation of spike structures in transitional boundary layers had close relationship with ring-like vortices. Especially, compared to the newly observed positive spike structure in the experiments, the same structure was found in the present numerical simulations, and the mechanism was also studied and analyzed.

关键词： boundary layer transition ring-like vortices spike structure direct numerical simulation

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Single and multiple stressor effect of road deicers and Cu on Atlantic salmon (Salmo salar) alevins from hatching till swim-up

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Journal of Environmental Sciences 2018年第4期30卷 368-378页

作者： Urma Mahrosh bjФrn Olav Rosseland Brit Salbu Hans-Christian Teien Nortuegian Uniuersity of Life Sciences Department of Environmental Sciences N-1432 As Norway National University of Sciences and Technology H-12 Islamabad Pakistan Norwegian University of Life Sciences Department of Ecology and Natural Resource Management N-1432 As Norway

Road salts are frequently used for deicing of roads in the Nordic countries. During snow-melt, the road run-off containing high concentrations of road salt and various metals such as Cu remobilized from sand, silt and dust may negatively influence organisms in downstream receiving water bodies. The present work focuses on the impact of road salt（NaCl） and Cu, separately and in mixtures on Atlantic salmon alevins from hatching till swim-up. The results showed that high road salt concentrations could induce a series of negative effects in alevins such as reduced growth, deformities, delayed swim-up and mortality. For alevins exposed to all tested road salt concentrations（100–1000 mg/L）,mortality was significantly higher compared to control. In exposure to Cu solutions（5–20 μg Cu/L）, no effects on growth, morphology, swim-up or mortality of alevins compared to control were observed. In mixture solutions（road salt and Cu）, ultrafiltration of the exposure water demonstrated that only 20%–40% of Cu was present as positively charged low molecular mass（LMM） Cu species assumed to be bioavailable. When exposed to road salt and Cu mixtures, negative effects in alevins such as reduced growth, deformities,delayed swim-up and mortality were observed. The overall results indicated that the road salt application could seriously affect sensitive life stages of Atlantic salmon, and application of road salt should be avoided during the late winter–early spring period.

关键词： Road deicers Copper Atlantic salmon Alevins Biological effects

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