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CT预测新辅助治疗下胰腺癌切除术后切缘阴性的准确性:系统综述及Meta分析

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国际医学放射学杂志 2021年第4期44卷 490-490页

作者： S.Park j.k.jang j.H.Byun j.H.kim S.S.Lee H.j.kim 孙羽

摘要目的系统评价新辅助治疗后 CT 预测可切除性胰腺导管腺癌(PDAC)切缘阴性(R0)的诊断准确性。方法在Pub Med、EMBASE 和 Cochrane 数据库中检索 2020 年 2 月 24

关键词：新辅助治疗胰腺癌系统综述切除术后

FATIGUE LIVES FOR INDUCTION HARDENED SHAFTS MATERIALS ACCORDING TO THE ENVIRONMENTAL TEMPERATURES

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 585-593页

作者： D.G. Lee k.C. jang j.M. kuk I.S. kim korea Institute of Industrial Technology Gwangju 506-824 Korea Dept. of Mechanical Engineering Mokpo National University Mokpo 534-729 Korea

Rotary bending fatigue tests were carried out with two kinds of materials, S43C and S50C, using the front engine and front drive shaft （FF shaft） of vehicle. The specimens were induction hardened about 1.0mm depth from the specimen surface, and the hardness value on the surface was about HRC56-60. The tested environment temperatures were -30, 25 and 80℃ in order to look over effect of the induction hardening and the environmental temperatures on the fatigue characteristics. The fatigue limit of induction hardened specimens increased more about 45% than non-hardened specimens showing that the endurances of S43C and S50C were 98.1 and 107.9MPa in non-hardened samples, 147.1 and 156.9MPa in hardened samplesrespectably. The maximum tensile and compressive stress on the small circular defect was about ＋250 and -450MPa respectively when circular defect is situated on top and bottom. The fatigue life increased 80, 25 and -30℃ in order regardless of hardening. In comparison of the fatigue lives on the basis of tested result at 25℃, the fatigue lives of non-hardened specimens decreased about 35%, but that of hardened specimens decreased about only 5% at 80℃ more than at 25℃. And fatigue life of non-hardened and hardened specimens were about 110% and 120% higher at -30℃ than that of 25℃. Based on the result of stress distribution near the defect, the tensile and compressive stress repeatedly generated by load direction were the largest on the small circular defect due to the stress concentration.

关键词： induction hardening fatigue test front engine and front drive shaft,fatigue crack fatigue life fatigue life ratio

Iridium oxide fabrication and application: A review

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journal of Energy Chemistry 2020年第7期29卷 152-172,I0005页

作者： Hansaem jang jaeyoung Lee Electrochemical Reaction&Technology Laboratory(ERTL) School of Earth Sciences and Environmental EngineeringGwangju Institute of Science and Technology(GIST)Gwangju 61005Republic of Korea Ertl Center for Electrochemistry and Catalysis GRIGISTGwangju 61005Republic of Korea

Despite the scarcity and cost of iridium oxide,it is still the material of choice in numerous fields of science and applications,including capacitors,electrochromism,sensors,and various oxidation electrocatalysis(e.g.,chlorine evolution reaction,detoxification,and oxygen evolution reaction).Such versatility is attributed to the distinct features of iridium oxides,such as their activity,biocompatibility,conductivity,and *** features and properties of iridium oxides are strongly dependent on the fabrication *** this review,methodologies relating to the synthesis and fabrication of solid-state iridium oxides have been thoroughly collected and *** and crystallization techniques for iridium oxides are also *** the end of the review,the effects of utilizing a certain fabrication method on the characteristics of the iridium oxide product are recapitulated,together with the recommended application of the product in various fields.

关键词： Iridium oxide Iridium dioxide Electrode Electrocatalyst Electrochromism pH sensor Oxygen evolution reaction

The role of host refuge and strong Allee effects in a host-parasitoid system

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International journal of Biomathematics 2023年第5期16卷 111-135页

作者： Xiaochuan Hu Sophia R.-j.jang Vinli Inc. DallasTX75206USA Department of Mathematics and Statistics Teras Tech University LubbockTX 79409USA

We propose and study a discrete host-parasitoid model of difference equations with a spatial host refuge where hosts in the refuge patch are free from parasitism but undergo a demographic strong Allee *** the growth rate of hosts in the non-refuge patch is less than one,a host Allee threshold is derived below which both populations become *** is proven that both populations can persist indefinitely if the host growth rate in the non-refuge patch exceeds one and the maximum reproductive number of parasitoids is greater than *** simulations reveal that the host refuge can either stabilize or destabilize the host-parasitoid interactions,depending on other model parameters.A large number of parasitoid turnover from a parasitized host may be detrimental to the parasitoids due to Allee effects in the hosts within the refuge ***,it is demonstrated numerically that if the host growth rate is not small,the population level of parasitoids may suddenly drop to a small value as some parameters are varied.

关键词： Host refuge strong Allee effect stabilizing and destabilizing Beverton-Holt growth rate Allee threshold maximum reproductive number

Asymptotic dynamics of a modified discrete Leslie-Gower competition system

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International journal of Biomathematics 2017年第6期10卷 1-23页

作者： Yunshyong Chow Sophia R.-j. jang Institute of Mathematics Academia Sinica Taipei 10617 Taiwan Department of Mathematics and StatisticsTexas Tech University Lubbock TX 79409-1042 USA

We propose a modified discrete-time Leslie-Gower competition system of two popula- tions to study competition outcomes. Depending on the magnitude of a particular model parameter that measures intraspecific competition between individuals within the same population, either one or both populations may be subject to Allee effects. The resulting system can have up to four coexisting steady states. Using the theory of planar compet- itive maps, it is shown that the model has only equilibrium dynamics. The competition outcomes then depend not only on the parameter regimes but may also depend on the initial population distributions.

关键词： Competition saddle points Allee effects.

Metabolic Plasticity of Nitrogen Assimilation by Porphyra umbilicalis(Linnaeus) kützing

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journal of Ocean University of China 2012年第4期11卷 517-526页

作者： jang k.kim George P.kraemer Charles Yarish Departments of Ecology and Evolutionary Biology and Marine Sciences University of Connecticut1 University PlaceStamfordCT 06901USA Department of Environmental Studies Purchase College735 Anderson Hill RoadPurchaseNY 10577USA

The physical stresses associated with emersion have long been considered major factors determining the vertical zona- tion of intertidal seaweeds. We examined Porphyra umbilicalis （Linnaeus） kiitzing thalli from the vertical extremes in elevation of an intertidal population （i.e. upper and lower intertidal zones） to determine whether Porphyra thalli acclimate to different vertical elevations on the shore with different patterns of nitrate uptake and nitrate reductase （NR） and glutamine synthetase （GS） activities in response to different degrees of emersion stress. We found that the nitrate uptake and NR recovery in the emersed tissues took longer in lower intertidal sub-population than in upper intertidal sub-population; and GS activity was also significantly affected by emersion and, interestingly, such an activity was enhanced by emersion of thalli from both upper and lower intertidal zones. These results sug- gested that intta-population variability in post-emersion recovery of physiological functions such as nutrient uptake and NR activity enables local adaptation and contributes to the wide vertical distribution ofP. umbilicalis. The high GS activity during periodic emer- sion stress may be a protective mechanism enabling P umbilicalis to assimilate nitrogen quickly when it again becomes available, and may also be an evidence ofphotorespiration during emersion.

关键词： emersion glutamine synthetase nitrate reductase nitrogen assimilation Porphyra

Schottky barrier modulation of bottom contact SnO_(2) thin-film transistors via chloride-based combustion synthesis

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journal of Materials Science & Technology 2023年第17期148卷 199-208页

作者： Bongho jang junhee Lee Hongki kang jaewon jang Hyuk-jun kwon Department of Electrical Engineering and Computer Science DGISTDaegu 42988South Korea School of Electronic and Electrical Engineering Kyungpook National UniversityDaegu 41566South Korea School of Electronics Engineering Kyungpook National UniversityDaegu 41566South Korea Convergence Research Advanced Centre for Olfaction DGISTDaegu 42988South Korea

The enhanced carrier flow at the interface between Au and SnO_(2)semiconductors,which initially form Schottky contacts,is realized using chloride-based combustion ***-based combustion sys-tems can achieve chlorine(Cl)doping effects as well as conversion to crystalline SnO_(2)films at clearly lower temperatures(∼250℃)than conventional *** to the Cl doping effect,the high carrier concentration can induce thin potential barriers at the metal/semiconductor(MS)junctions,resulting in carrier injection by *** a result,compared to conventional SnO_(2)thin-film transistors,the de-vices fabricated by combustion synthesis exhibit significantly improved electrical performance with field-effect mobility of 6.52 cm 2/Vs(∼13 times),subthreshold swing of 0.74 V/dec,and on/offratio of∼10^(7)below 300℃.Furthermore,because of the enhanced tunneling carriers induced by the narrowed barrier width,the Schottky barriers are significantly reduced from 0.83 to 0.29 eV(65%decrease)at 250℃and from 0.42 to 0.17 eV(60%decrease)at 400℃.Therefore,chloride-based combustion synthesis can con-tribute to developing SnO_(2)-based electronics and flexible devices by achieving both high-quality oxide films and improved current flow at the MS interface with low-temperature annealing.

关键词： SnO_(2) Combustion Sol-gel Schottky contact Thin-film transistors

Cooperative hunting in a discrete predator-prey system

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International journal of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow Sophia R-j.jang Hua-Ming Wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Department of Mathematics and Statistics Texas Tech University LubbockTX 79409USA Department of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We propose and investigate a discrete-time predator-prey system with cooperative hunting in the predator *** model is constructed from the classical Nicholson-Bailey host-parasitoid system with density dependent growth rate.A sufficient condition based on the model parameters for which both populations can coexist is derived,namely that the predator’s maximal reproductive number exceeds *** study existence of interior steady states and their stability in certain parameter *** is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is *** cooperative hunting,however,may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

关键词： Cooperative hunting discrete predator-prey system predator persistence Neimark-Sacker bifurcation

Experimental and finite element analysis for fracture of coating layer of galvannealed steel sheet

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 111-116页

作者： S.I.kIM j.U.HER Y.C.jang Y.LEE Sheet Products and Process Research Group POSCO Techology Research Laboratory Department of Mechanical Engineering Chung-Ang University

Mechanical properties of galvannealed (GA) steel sheet used for automotive exposed panel and predicted failure phenomenon of its coating layer were evaluated using finite element method. V-bending test was performed to understand better the fracture of coating layer of GA steel sheet during plastic deformation. Yield strength of the coating layer was calculated by using a relative difference between hardness of coating layer measured from the nano-indentation test and that of substrate. To measure shearing strength at the interface between substrate and coating layer, shearing test with two specimens attached by an adhesive was carried out. Using the mechanical properties measured, a series of finite element analyses coupled with a failure model was performed. Results reveal that the fracture of coating layer occurs in an irregular manner at the region where compressive deformation is dominant. Meanwhile, a series of vertical cracks perpendicular to material surface are observed at the tensile stressed-region. It is found that 0.26-0.28 of local equivalent plastic strain exists at the coating and substrate at the beginning of failure. The fracture of coating layer depends on ductility of the coating layer considerably as well.

关键词： galvannealed steel sheet fracture simulation coating layer finite element analysis, failure model