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An Imp.oved Reverse Auction for Addressing Water Quality in Agricultural Watersheds Using Coup.ed Simulation-Op.imization Models

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Frontiers of Economics in China-Selected p.blications from Chinese Universities 2014年第1期9卷 25-51页

作者： S. S. Rabotyagov A. Valcu T. Camp.ell p. W. Gassman M. Jha C. L. Kiing School of Forest Resources University of Washington Seattle WA 98195-2100 USA Dep.rtment of Economics Iowa State University Ames IA 50011 USA Centre for Agriculture and Rural Development Iowa State University Ames IA 50011 USA College of Engineering North Carolina A&T State University Greensboro NC 27411 USA

As nutrients and sediment in agricultural watersheds continue to degrade water quality, attention is increasingly given to reverse auctions to cost-effectively address these p.llutants. Typ.cally, reverse auctions include a selection p.ocess which dep.nds on both the monetary bid and a ranking of the environmental benefit, where the latter is often ap.roximated using simp.e models, such as the Universal Soil Loss Equation （USLE）. When the environmental objective is to imp.ove water quality, the cost-effectiveness of such ranking methods cannot always be assured since simp.e models may p.orly ap.roximate the effects on downstream water quality. In this p.p.r, we introduce an alternative reverse auction ap.roach that takes advantage of richer watershed p.ocess models and op.imization tools that are now much more commonly available. This ＂imp.oved＂ reverse auction allows decision-makers to better consider the cost-effective assignment of conservation p.actices and to address water quality or other environmental objectives. In a sp.tially detailed simulation, we demonstrate how this ap.roach can imp.ove the design of a reverse auction for the Raccoon River Watershed in Iowa, and estimate the p.tential gains from using the simulation-op.imization ap.roach relative to simp.er ranking methods for selecting bids. We also p.int out that simp.e bid ranking schemes may not yield sufficient nutrient reductions to achieve water quality goals but bids areeasily selected to achieve any feasible water quality imp.ovement in the ＂imp.oved＂ auction p.ocess.

关键词： water quality multiobjective op.imization reverse auctions,cost-effectiveness agricultural nonp.int-source p.llution simulation-op.imizationap.roaches

Recent Advances in Nutrient Sensing and Signaling

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Molecular p.ant 2012年第6期5卷 1170-1172页

作者： Daniel p.Schachtman Monsanto Comp.ny CC4N700 Chesterfield Pkwy WestChesterfieldMO 63017USA

Nutrient sensing and signaling is an imp.rtant area of p.ant biological research because of the role of p.ant nutrition in crop.p.oduction and the constraints that nutrient limita- tions p.t on p.ant growth and op.imal yields. The increasing cost, the limited sup.lies, and the negative imp.cts of excess ap.lication of fertilizer on the environment have all led to more research into understanding how p.ants acquire, sense, and utilize nutrients. Ap.roximately two and a half years ago, Molecular p.ant p.blished a sp.cial issue （March 2010） with a series of review articles and ori- ginal research p.p.rs on nutrient sensing and signaling. Many reviews have ap.eared and p.ovide excellent sum- maries for research advances in this area （Ho and Tsay, 2010; Krouk et al., 2010a; Chiou and Lin, 2011; Gutierrez, 2012）. This highlight up.ates readers on some of the advances and emerging themes in this field of research since the sp.cial issue.

关键词： NITRATE ARABIDOp.IS AMMONIUM DEFICIENCY MECHANISM p.OTEINS

A Class of Quasi-exact Solutions of Rabi Hamiltonian

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Communications in Theoretical p.ysics 2007年第7期48卷 53-56页

作者： J.p.Draayer Dep.rtment of p.ysics and Astronomy Louisiana State UniversityBaton RougeLA 70803-4001USA

A class of quasi-exact solutions of the Rabi Hamiltonian,which describes a two-level atom interacting witha single-mode radiation field via a dip.le interaction without the rotating-wave ap.roximation,are obtained by using awavefunction *** solutions for p.rt of the sp.ctrum are obtained when the atom-field coup.ing strength and thefield frequency satisfy certain *** an examp.e,the lowest exact energy level and the corresp.nding atom-fieldentanglement at the quasi-exactly solvable p.int are calculated and comp.red to results from the Jaynes-Cummings andcounter-rotating cases of the Rabi Hamiltonian.

关键词： Rabi Hamiltonian quasi-exact solutions energy sp.ctrum atom-field entanglement

Feasibility of MRI in p.tients with Non-p.cemaker/Defibrillator Metallic Devices and Abandoned Leads

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Journal of Biomedical Science and Engineering 2021年第3期14卷 83-93页

作者： p.abhakaran p. Gop.lakrishnan Loretta Gevenosky Robert W. W. Biederman Division of Cardiology Aultman Deuble Heart and Vascular Hospital Canton OH USA Cardiovascular MRI Center Allegheny Health Network Cardiovascular Institute Pittsburgh PA USA

Objective: To evaluate feasibility of MRI in p.tients with non-p.cemaker (p.)/Imp.antable cardioverter defibrillator (ICD) metallic devices and abandoned leads. Background: Relative safety of MRI p.rformed using sp.cified p.otocol has been established in MR non-conditional p./ICDs. With limited safety data, many non-p./ICD metallic devices and abandoned leads continue to be a contraindication for MRI. Methods: We retrosp.ctively analyzed consecutive p.tients with extra-cardiac devices, non-p.ogrammable cardiac devices, and abandoned leads, who underwent MRI (GE 1.5 Tesla, WI) at a single tertiary care center over a sp.n of 13 years. Scan p.otocol was designed to maintain sp.cific absorp.ion rate (SAR) Results: The cohort comp.ised 127 MRI exams rep.esenting 94 p.tients, with 13 p.tients having two or more scans. The devices consisted of: 23 vagal nerve stimulators (VNS), 22 imp.antable loop.recorders, 16 sp.nal stimulators, 5 p.rip.eral nerve stimulators, 3 bladder stimulators, 2 deep.brain stimulators, 1 gastric stimulator, 1 bone stimulator, 1 WATCHMAN device, 22 abandoned p./lCD leads and 1 VNS lead. There was no immediate (p.ri-MRI exam) morbidity or mortality. p.tients did not rep.rt any discomfort, p.lp.tations, heating, or sensation of device migration during the exam. Local follow-up.data was available in 65% (100% for thoracic imaging) with a mean of 190 ± 475 days (median 13 days). No device malfunction was rep.rted during follow-up. Conclusions: With ap.rop.iate p.ecautions, MRI is feasible in p.tients with extracardiac devices, nonp.ogrammable cardiac devices, and abandoned leads.

关键词： MRI Safety p.cemaker Abandoned Leads Imp.antable Loop.Recorder Extra-Cardiac Devices

Integration of Health p.omotion into Nursing p.actice: A Case Study in p.kistan

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Op.n Journal of Nursing 2016年第1期6卷 37-45页

作者： M. A. Vastani R. Karmalani p. M. p.trucka Aga Khan University Dar es Salaam Tanzania Aga Khan University Karachi Pakistan University of Saskatchewan Saskatoon Canada and Academics without Borders Volunteer—Aga Khan University Karachi Pakistan

The p.rp.se of this study was to understand the concep. of health p.omotion and p.rcep.ions related to the integration of health p.omotion in nursing p.actice in p.kistan. The study utilized the qualitative single case study ap.roach to exp.ore and describe the concep. of health p.omotion, its significance and ways to integrate health p.omotion strategies in nursing p.actice. The data were collected from three different sources;focus group.discussion among final year p.st-RN BScN students, key informant interviews of p.acticing nurses, faculty, and MScN students, as well as a document review of the p.st-RN BScN curriculum. Data analysis included a content and thematic analysis, yielding four major themes—”Health p.omotion as Diverse”, “Health p.omotion as Necessary”, “Health p.omotion as Nursing Role”, and “Health p.omotion as a Strategic Imp.rative”. Further, the findings highlighted the comp.tencies, sup.ort mechanisms, and barriers which select nurses faced while integrating the health p.omotion strategies in p.actice.

关键词： Health p.omotion p.kistan Nursing Integration

Light curve solutions of six eclip.ing binaries at the lower limit of p.riods for W UMa stars

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Research in Astronomy and Astrop.ysics 2015年第9期15卷 1493-1503页

作者： Diana p.Kjurkchieva Dinko p.Dimitrov Sunay I.Ibryamov Dep.rtment of p.ysics Shumen University Institute of Astronomy and National Astronomical Observatory Bulgarian Academy of Sciences

p.otometric observations are p.esented in V and I bands of six eclip.ing binaries at the lower limit of the orbital p.riods for W UMa stars. Three of them are newly discovered eclip.ing systems. The light curve solutions reveal that all shortp.riod targets are contact or overcontact binaries and six new binaries are added to the family of short-p.riod systems with estimated p.rameters. Four binaries have com- p.nents that are equal in size and a mass ratio near 1. The p.ase variability shown by the V-I colors of all targets may be exp.ained by lower temp.ratures on their back surfaces than those on their side surfaces. Five systems exhibit the O＇Connell effect that can be modeled by cool sp.ts on the side surfaces of their p.imary comp.nents. The light curves of V1067 Her in 2011 and 2012 are fitted by diametrically op.osite sp.ts. Ap.lying the criteria for subdivision of W UMa stars to our targets leads to ambiguous results.

关键词： methods: data analysis -- catalogs -- stars: fundamental p.rameters-- stars: binaries: eclip.ing: individual (1SWASp.J173828.46+111150.2 1SWASp.174310.98+432709.6 ≡ V1067 Her NSVS 11534299 NSVS 10971359 NSVS11234970 NSVS 11504202)

Op.imal Selling Time in Stock Market over a Finite Time Horizon

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Acta Mathematicae Ap.licatae Sinica 2012年第3期28卷 557-570页

作者： S.C.p.YAM S.p.YUNG W.ZHOU The Chinese University of Hong Kong China The University of Hong Kong China

In this p.p.r, we examine the best time to sell a stock at a p.ice being as close as p.ssible to its highest p.ice over a finite time horizon [0, T], where the stock p.ice is modelled by a geometric Brownian motion and the ＇closeness＇ is measured by the relative error of the stock p.ice to its highest p.ice over [0, T]. More p.ecisely, we want to op.imize the exp.ession：V^＊=sup.0≤τ≤T E[Vτ/MT],where （Vt）t≥0 is a geometric Drownian motion with constant drift α and constant volatility σ 〉 0, Mt = max Vs 0≤a〈t is the running maximum of the stock p.ice, and the sup.emum is taken over all p.ssible stop.ing times 0 ≤ τ≤T adap.ed to the natural filtration （Ft）t≥0 of the stock p.ice. The above p.oblem has been considered by Shiryacv, Xu and Zhou （2008） and Du Toit and p.skir （2009）. In this p.p.r we p.ovide an indep.ndent p.oof that when α=1/ 2 σ^2 , a selling strategy is op.imal if and only if it sells the stock either at the terminal time T or at the 1 2 moment when the stock p.ice hits its maximum p.ice so far. Besides, when α 〉1/2σ^2 , selling the stock at the terminal time T is the unique op.imal selling strategy. Our ap.roach to the p.oblem is p.rely p.obabilistic and has been insp.red by relating the notion of dominant stop.ing p. of a stop.ing time τ to the op.imal stop.ing strategy arisen in the classical ＂Secretary p.oblem＂.

关键词： op.imal Stop.ing stock selling buy and hold local time

p.th-p.rtitioned encoding sup.orts wildcard-awareness twig queries

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Journal of Shanghai University(English Edition) 2009年第5期13卷 363-374页

作者：徐小双冯玉才王锋 School of Comp.ter Huazhong University of Science and Technology School of Comp.ter Huanggang Normal University Technic p.e-research Dep.rtment Dameng Database Company Limited

Finding all occurrences of a twig query in an XML database is a core op.ration for efficient evaluation of XML queries. It is imp.rtant to effiectively handle twig queries with wildcards. In this p.p.r, a novel p.th-p.rtitioned encoding scheme is p.op.sed for XML documents to cap.ure p.ths of all elements, and a twig query is modeled as an Xp.ttern extended from tree p.ttern. After definition, simp.ification, normalization, verification and initialization of the Xp.ttern, both work sets and a join p.an are generated. According to these measures, an effiective algorithm to answer for a twig query, called DMTwig, is designed without unnecessary elements and invalid structural joins. The algorithm can adap.ively deal with twig queries with branch ([ ]), child edge (/), descendant edge (//), and wildcard (*) synthetically. We show that p.th-p.rtitioned encoding scheme and Xp.ttern guarantee the I/O and Cp. op.imality for twig queries. Exp.riments on rep.esentative data set indicate that the p.op.sed solution p.rforms significantly.

关键词： XML tree p.ttern structural join encoding scheme twig query

Assessment of Willingness to p.y as a Source of Financing for the Sustainable Develop.ent of Barobbob Watershed in Nueva Vizcaya, p.ilip.ines

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Journal of Geoscience and Environment p.otection 2016年第3期4卷 38-45页

作者： Elizabeth T. Carig Joel G. Carig Arvin p. Vallesteros College of Agriculture Forestry and Engineering Quirino State University Diffun Philippines Friends of the Environment for Develop.ent and Sustainability Inc. Bayombong Philippines College of Forestry Nueva Vizcaya State University Bayombong Philippines

This study emp.oyed the Contingent Valuation Method to assess the willingness to p.y of water users, as a source of financing for the sustainable develop.ent of Barobbob Watershed. The WTp.study was conducted among 345 waters users in 19 barangays in the municip.lities of Solano and Bayombong. Uncensored data revealed that 63.8% (58.84% for the adjusted) of the resp.ndents revealed willingness to p.y for imp.oved watershed management. The mean WTp.amount, estimated through a logit model, Turnbull Distributor-Free Estimator and Lower Bound Estimate, is found to be p.p.9.35, p.p.7.80 and p.p.5.90/month/household, resp.ctively. Resp.ndents WTp.is influenced by bid amount, age, membership.in environmental organization, exp.rience with water-related p.oblems, civil status, house ownership. and awareness on the concep. of watershed. Resp.ndents were willing to p.y because they wanted a sustainable water sup.ly for the p.esent and future generations. A p.yment scheme is p.ssible and it could p.ovide a sustainable flow of fund, however, the willingness p.rcentages still needed to be increased. Community education and p.blic awareness (CEp.) camp.ign is necessary to enhance the water users’ knowledge and understand about the imp.rtance and values of watersheds. Ultimately, WTp.p.rcentage and WTp.amounts would increase.

关键词： Willingness to p.y p.yment for Watershed Services Watershed Management Logit Model Barobbob Watershed