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Domination Number in Graphs with Minimum Degree Two

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Acta Mathematica Sinica,English Series 2009年第8期25卷 1253-1268页

作者： Er Fang SHAN Moo Young SOHN Xu Dong YUAN Michael A. henning Department of Mathematics Shanghai University Shanghai 200444 P. R. China Department of Applied Mathematics Changwon National University 641-773 Changwon Korea Department of Mathematics Guangxi Normal University Guilin 541004 P. R. China School of Mathematical Sciences University of KwaZulu-Natal Pietermaritzburg 3209 South Africa

A set D of vertices of a graph G = （V, E） is called a dominating set if every vertex of V not in D is adjacent to a vertex of D. In 1996, Reed proved that every graph of order n with minimum degree at least 3 has a dominating set of cardinality at most 3n/8. In this paper we generalize Reed＇s result. We show that every graph G of order n with minimum degree at least 2 has a dominating set of cardinality at most （3n ＋IV21）/8, where V2 denotes the set of vertices of degree 2 in G. As an application of the above result, we show that for k ≥ 1, the k-restricted domination number rk （G, γ） ≤ （3n＋5k）/8 for all graphs of order n with minimum degree at least 3.

关键词： graph dominating set domination number restricted domination number

Tunable diameter electrostatically formed nanowire for high sensitivity gas sensing

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Nano Research 2015年第7期8卷 2206-2215页

作者： Alex henning Nandhini Swaminathan Andrey Godkin Gil Shalev Iddo Amit Yossi Rosenwaks Department of Physical Electronics School of Electrical Engineering TeI-Aviv University Ramat-Aviv 69978 Israel

We report on an electrostatically formed nanowire （EFN）-based sensor with tunable diameters in the range of 16 nm to 46 nm and demonstrate an EFN- based field-effect transistor as a highly sensitive and robust room temperature gas sensor. The device was carefully designed and fabricated using standard integrated processing to achieve the 16 nm EFN that can be used for sensing without any need for surface modification. The effective diameter for the EFN was determined using Kelvin probe force microscopy accompanied by three- dimensional electrostatic simulations. We show that the EFN transistor is capable of detecting 100 parts per million of ethanol gas with bare SiO2.

关键词： gas sensing,silicon nanowires, Kelvin probe forcemicroscopy (KPFM), electrostatic confinement,multiple gate transistor

近海应用中土壤-结构界面的亚塑性模型（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第8期19卷 624-637页

作者： Hans henning STUTZ Frank WUTTKE Department of Engineering Aarhus University Institute of Geo-Science Kiel University

目的:研究一种使用连续的土壤模型模拟土壤-结构界面的新方法,并阐述这些模型增强土壤-结构相互作用的建模方法。创新点:1.基于先前的亚塑性模型,通过将晶粒间应变的概念融入模型公式来模拟循环载荷。2.整体性较好的模型具有更好、更精... 详细信息

目的:研究一种使用连续的土壤模型模拟土壤-结构界面的新方法,并阐述这些模型增强土壤-结构相互作用的建模方法。创新点:1.基于先前的亚塑性模型,通过将晶粒间应变的概念融入模型公式来模拟循环载荷。2.整体性较好的模型具有更好、更精确的模拟结果。方法:1.采用一种砂浆接触的力学方法,其中一个表面作为主面,另一个表面作为从属面。2.采用砂浆接触的力学方法并结合用户定义的子程序,对土壤-结构界面进行建模。3.基于先前的亚塑性模型,将晶粒间应变的概念融入模型公式来模拟循环载荷。结论:1.整体性较好的模型具有更好、更精确的模拟结果。2.本文提出的土壤-结构界面建模方法不仅提高了模拟结果,且在某些模拟中提高了数值收敛性。

关键词：亚塑性接触面循环荷载细颗粒和粗粒土

Evaluation of growth and reproduction as indicators of soil metal toxicity to the Collembolan, Sinella curviseta

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Insect Science 2009年第1期16卷 57-63页

作者： Jie Xu Xin Ke Paul henning Krogh Yin Wang Yong-Ming Luo Jing Song Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Department of Terrestrial Ecology National Environmental Research Institute University of Aarhus Vejlsevej 25 DK-8600 Silkeborg Denmark Soil and Environment Bioremediation Research Centre Institute of Soil Sciences Chinese Academy of Sciences Nanjing China

Laboratory studies evaluated the sensitivity of Sinella curviseta Brook （Collembola： Entomobryidae） to selected heavy metals （Cu, Pb and Zn）. Survival, reproduction and growth of S. curviseta were determined in a 4-week exposure test in an agricultural soil amended with metals to concentrations of 100, 200, 400, 800, 1 600 and 3 200 mg/kg. Results showed reduction in adult survival and reproductive failure at the highest concentrations （3 200 mg/kg） of Cu and Zn. EC50reproduction values for Cu and Zn were approximately 442 and 2 760 mg/kg, respectively. Application of Pb at all levels resulted in large numbers of progeny and no significant mortality compared to controls. Adult growth rate decreased for all metal treatments compared to the controls, suggesting that metals affect S. curviseta metabolism and result in slower growth. We showed that reproduction is a slightly more sensitive parameter than growth. Since a growth test needs fewer juveniles and takes less time than a reproduction test, we conclude that the two parameters are complementary and could be used for a better ecotoxicological evaluation of contaminant levels. However, relative growth and reproduction sensitivities should be tested with more chemicals before a growth test is accepted as a faster sublethal test than a reproduction test.

关键词： Collembolan copper growth lead reproduction Sinella curviseta soil pollution toxicity testing zinc

Social Choice Meets Graph Drawing: How to Get Subexponential Time Algorithms for Ranking and Drawing Problems

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Tsinghua Science and Technology 2014年第4期19卷 374-386页

作者： henning Fernau Fedor V.Fomin Daniel Lokshtanov Matthias Mnich Geevarghese Philip Saket Saurabh FB 4-Abteilung Informatikwissenschaften Universitt Trier D-54286 TrierGermany the Department of Informatics University of Bergen N-5020 Bergen Norway Max-Planck-Institut fr Informatik D-66123 Saarbrcken Germany the Institute of Mathematical Sciences Chennai - 600113 India

We analyze a common feature of p-Kemeny AGGregation（p-KAGG） and p-One-Sided Crossing Minimization（p-OSCM） to provide new insights and findings of interest to both the graph drawing community and the social choice community. We obtain parameterized subexponential-time algorithms for p-KAGG—a problem in social choice theory—and for p-OSCM—a problem in graph drawing. These algorithms run in time O＊（2O（√k log k））,where k is the parameter, and significantly improve the previous best algorithms with running times O.1.403k/and O.1.4656k/, respectively. We also study natural ＂above-guarantee＂ versions of these problems and show them to be fixed parameter tractable. In fact, we show that the above-guarantee versions of these problems are equivalent to a weighted variant of p-directed feedback arc set. Our results for the above-guarantee version of p-KAGG reveal an interesting contrast. We show that when the number of ＂votes＂ in the input to p-KAGG is odd the above guarantee version can still be solved in time O＊（2O（√k log k））, while if it is even then the problem cannot have a subexponential time algorithm unless the exponential time hypothesis fails（equivalently, unless FPT D M[1]）.

关键词： Kemeny aggregation one-sided crossing minimization parameterized complexity subexponential-time algorithms social choice theory graph drawing directed feedback arc set

Simplified modeling of electromagnets for dynamic simulation of transient effects for a synchronous electric motor

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International Journal of Mechanical System Dynamics 2021年第1期1卷 89-95页

作者： Florian Bechler Julius Kesten Florian Wittemann Frank henning Martin Doppelbauer Peter Eberhard Institute of Engineering and Computational Mechanics University of StuttgartStuttgartGermany Institute of Electrical Engineering Karlsruhe Institute of Technology(KIT)KarlsruheGermany Institute of Vehicle System Technology Karlsruhe Institute of Technology(KIT)KarlsruheGermany

This study aims to show an approach for the dynamic simulation of a synchro-nous *** magnetic forces in the air gap are calculated efficiently using simplified approaches without neglecting important *** the modeling of the magnetic forces,an equivalent magnetic circuit is constructed in which the magnetic saturation and the leakage flux are taken into account and coupled with the electrical circuit at the *** calculated magnetic forces are then passed to a mechanical model of the *** with a predefinable load torque,the resulting motor rotation and the forces in the bearings are *** presented model is then investigated in a small *** novel ap-proach is intended to provide a method of calculating dynamically the forces transmitted from the shaft to the motor housing and to create the basis for evaluating electric motors for vibrations,noise,and harshness under varying loads and input voltages.

关键词： dynamic simulation electromagnet electromagnet modeling magnetomotive forces

Comparison of outcomes between complete and incomplete congenital duodenal obstruction

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World Journal of Gastroenterology 2019年第28期25卷 3787-3797页

作者： Stefan Gfroerer Till-Martin Theilen henning C Fiegel Anoosh Esmaeili Udo Rolle Department of Pediatric Surgery and Pediatric Urology University Hospital Frankfurt Frankfurt 60590 Germany Department of Pediatric Cardiology University Hospital Frankfurt Frankfurt 60590 Germany

BACKGROUND Congenital duodenal obstruction (CDO) can be complete (CCDO) or incomplete (ICDO). To date there is no outcome analysis available that compares both subtypes. AIM To quantify and compare the association between CCDO and ICDO with outcome parameters. METHODS We retrospectively reviewed all patients who underwent operative repair of CCDO or ICDO in our tertiary care institution between January 2004 and January 2017. The demographics, clinical presentation, preoperative diagnostics and postoperative outcomes of 50 patients were compared between CCDO (n = 27;atresia type 1-3, annular pancreas) and ICDO (n=23;annular pancreas, web, Ladd′s bands). RESULTS In total, 50 patients who underwent CDO repair were enrolled and followed for a median of 5.2 and 3.9 years (CCDO and ICDO, resp.). CCDO was associated with a significantly higher prenatal ultrasonographic detection rate (88% versus 4%;CCDO vs ICDO, P<0.01), lower gestational age at birth, lower age and weight at operation, higher rate of associated congenital heart disease (CHD), more extensive preoperative radiologic diagnostics, higher morbidity according to Clavien-Dindo classification and comprehensive complication index (all P≤0.01). The subgroup analysis of patients without CHD and prematurity showed a longer time from operation to the initiation of enteral feeds in the CCDO group (P<0.01). CONCLUSION CCDO and ICDO differ with regard to prenatal detection rate, gestational age, age and weight at operation, rate of associated CHD, preoperative diagnostics and morbidity. The degree of CDO in mature patients without CHD influences the postoperative initiation of enteral feeding.

关键词： Congenital duodenal obstruction Duodenal atresia Duodenal stenosis Prenatal ultrasonographic detection rate Clinical presentation Preoperative diagnostics Adverse events Outcome

Abdominal cocoon in children: A case report and review of literature

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World Journal of Gastroenterology 2021年第37期27卷 6332-6344页

作者： Daniel Keese Andrea Schmedding Kerstin Saalabian Georgy Lakshin henning Fiegel Udo Rolle Goethe-University Frankfurt Department of Paediatric Surgery and Paediatric UrologyUniversity HospitalFrankfurt 60590Germany

BACKGROUND Abdominal cocoon or“encapsulating peritoneal sclerosis”(EPS)is an uncommon and rare cause of intestinal *** a few cases have been reported in paediatric ***,EPS is described as the primary form in young adolescent girls from tropical and subtropical countries because of viral peritonitis due to retrograde menstruation or a history of peritoneal *** patients are asymptomatic or present with abdominal pain,which is likely to occur secondary to subacute bowel *** at imaging,such as ultrasound,computed tomography,and magnetic resonance imaging,are often *** diagnosed,EPS is characterized by total or partial encasement of the bowel within a thick fibrocollagenous membrane that envelopes the small intestine in the form of a cocoon because of chronic intraabdominal fibroinflammatory *** membrane forms a fibrous tissue sheet that covers,fixes,and finely constricts the gut,compromising its *** SUMMARY We present a case of EPS in a 12-year-old boy 8 wk after primary surgery for resection of symptomatic jejunal *** was no history of peritoneal dialysis or drug *** In this report,we sought to highlight the diagnostic,surgical,and histopathological characteristics and review the current literature on EPS in paediatric patients.

关键词： Abdominal cocoon Peritoneal encapsulation Encapsulating peritoneal sclerosis Intestinal obstruction Children Case report

The ethics of creativity

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The ethics of creativity