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簡介:IDENTIFYINGELEMENTSOFPOORCONSTRUCTIONSAFETYMANAGEMENTINCHINACMTAMA,,SXZENGA,B,ZMDENGAADEPARTMENTOFBUILDINGANDCONSTRUCTION,CITYUNIVERSITYOFHONGKONG,83TATCHEEAVENUE,KOWLOON,HONGKONGBAETNASCHOOLOFMANAGEMENT,SHANGHAIJIAOTONGUNIVERSITY,SHANGHAI,PRCHINARECEIVED9APRIL2002RECEIVEDINREVISEDFORM23APRIL2003ACCEPTED12MAY2003ABSTRACTCONSTRUCTIONISONEOFTHEMOSTHAZARDOUSINDUSTRIESDUETOITSUNIQUENATUREMEASUREDBYINTERNATIONALSTANDARDS,CONSTRUCTIONSITESAFETYRECORDSINCHINAAREPOORTHISPAPERAIMSTOEXAMINETHESTATUSOFSAFETYMANAGEMENTINTHECHINESECONSTRUCTIONINDUSTRY,EXPLORETHERISKPRONEACTIVITIESONCONSTRUCTIONSITES,ANDIDENTIFYFACTORSAFFECTINGCONSTRUCTIONSITESAFETYTHEFINDINGSREVEALTHATTHEBEHAVIOROFCONTRACTORSONSAFETYMANAGEMENTAREOFGRAVECONCERN,INCLUDINGTHELACKOFPROVISIONOFPERSONALPROTECTIONEQUIPMENT,REGULARSAFETYMEETINGS,ANDSAFETYTRAININGTHEMAINFACTORSAFFECTINGSAFETYPERFORMANCEINCLUDE?POORSAFETYAWARENESSOFTOPMANAGEMENT?,?LACKOFTRAINING?,?POORSAFETYAWARENESSOFPROJECTMANAGERS?,?RELUCTANCETOINPUTRESOURCESTOSAFETY?AND?RECKLESSOPERATIONS?THESTUDYALSOPROPOSESTHATTHEGOVERNMENTSHOULDPLAYAMORECRITICALROLEINSTRICTERLEGALENFORCEMENTANDORGANIZINGSAFETYTRAININGPROGRAMS?2003ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSCONSTRUCTIONOCCUPATIONALACCIDENTSAFETYFACTORANALYSIS1INTRODUCTIONALLOVERTHEWORLD,CONSTRUCTIONISONEOFTHEMOSTHAZARDOUSINDUSTRIESDUETOITSUNIQUENATUREJANNADIANDBUKHAMSIN,2002CONSTRUCTIONSAFETYISALWAYSAGRAVECONCERNFORBOTHPRACTITIONERSANDRESEARCHERSANUMBEROFCAUSESINFLUENCINGSAFETYPERFORMANCEINTHECONSTRUCTIONINDUSTRYHAVEBEENIDENTIFIEDTHATINCLUDECORRESPONDINGAUTHORTEL85227887609FAX85227887612EMAILADDRESSBCTAMCITYUEDUHKCMTAM09257535/SEEFRONTMATTER?2003ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JSSCI200309001SAFETYSCIENCE422004569–581WWWELSEVIERCOM/LOCATE/SSCISTRUCTIONMARKETSANDCONSTRUCTIONINSTITUTIONS,ANDMONITORINGCONSTRUCTIONSAFETYTHEROLEOFTHECENTRALMINISTRYISMIRROREDBYTHEPROVINCIALCONSTRUCTIONDEPARTMENTSANDTHOSEOFTHEINDEPENDENTMUNICIPALITIESTHEYARECHARGEDWITHTHERESPONSIBILITYFORCONSTRUCTIONSAFETYSEEFIG1UNDERPOWERSINTHERELEVANTLEGISLATIONONCONSTRUCTIONSAFETY,SUCHAS?CONSTRUCTIONLAW?,?INSPECTIONSTANDARDSFORCONSTRUCTIONSAFETY?AND?INSPECTIONSTANDARDSFORLABOURPROTECTIONINCONSTRUCTIONENTERPRISES?,THEMINISTRYOFCONSTRUCTIONANNUALLYHIRESABOUT50SAFETYAUDITORSTOCONDUCTNATIONWIDESAFETYAUDITSTHESCOPEOFTHEAUDITSINCLUDESTHESAFETYMANAGEMENTSYSTEMOFTHECONSTRUCTIONFIRMS,LABOURPROTECTIONMEASURES,SAFETYPITFALLSONCONSTRUCTIONSITESANDSOONINDIFFERENTPROVINCESORMAJORCITIES22SAFETYMANAGEMENTSYSTEMOFCONSTRUCTIONFIRMSPROTECTIONOFLABOURFROMOCCUPATIONALDISEASESANDACCIDENTSINTHECONSTRUCTIONINDUSTRYOFCHINAISDEFINEDBYLAWFOREXAMPLE,FORCONSTRUCTIONSITESHAVING50EMPLOYEESORMORE,MAINCONTRACTORSHAVETONOMINATEAFULLTIMESAFETYINSPECTORFORSITESWITHANAREAEXCEEDING10,000M2THEREMUSTBE2–3SAFETYINSPECTORSWHEREVERTHESITEEXCEEDS50,000M2,THEMAINCONTRACTORHASTOESTABLISHASAFETYMANAGEMENTTEAM23CONSTRUCTIONPROJECTSUPERVISORS’INSPECTIONONSAFETYSINCE1989CHINAHASBEGUNADOPTINGTHE?CONSTRUCTIONSUPERVISIONSCHEME?ONEOFTHEPROJECTSUPERVISORENGINEER?SRESPONSIBILITIESISTOMONITORCONSTRUCTIONSAFETYCMTAMETAL/SAFETYSCIENCE422004569–581DEPARTMENTOFCONSTRUCTIONMANAGEMENTMINISTRYOFCONSTRUCTIONDIVISIONOFCONSTRUCTIONMANAGEMENTDEPARTMENTOFCONSTRUCTIONOFPROVINCESANDINDEPENDENTMUNICIPALITIESDIVISIONOFCONSTRUCTIONMANAGEMENTDEPARTMENTOFCONSTRUCTIONOFCOUNTIESANDCITIESCONSTRUCTIONFIRMSCONTRACTORSCONSTRUCTIONFIRMSDIRECTLYLINKEDTOTHECENTRALCONSTRUCTIONFIRMSDIRECTLYLINKEDTOPROVINCESANDINDEPENDENTMUNICIPALITIESFIG1GOVERNANCEHIERARCHYFORCONSTRUCTIONSAFETYMANAGEMENT571
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簡介:BUILDHASABROADERMEANINGINTHISCONTEXT,IMPLYINGCREATIONOFTHEKINDTHAT,INENGLISH,ISSIMPLYCALLEDDESIGNTHEBAUHAUSDEVELOPEDANEWEDUCATIONALPROGRAMTHATATTEMPTEDTOESTABLISHARELATIONBETWEENTHEEMERGINGMODERNISMOFTHEFINEARTSANDABROADRANGEOFDESIGNANDCRAFTFIELDS,INCLUDINGARCHITECTURE,TOWNPLANNING,ADVERTISINGANDEXHIBITIONDESIGN,STAGEDESIGN,PHOTOGRAPHYANDFILM,ANDTHEDESIGNOFOBJECTSINWOOD,METAL,CERAMICS,ANDTEXTILESINSHORT,WHATHASCOMETOBEKNOWNASINDUSTRIALDESIGNTHEBAUHAUSPROGRAMBEGANWITHANINTRODUCTORYYEAROFSTUDIESDEVOTEDTOABSTRACTDESIGNINTWOANDTHREEDIMENSIONS,ANDSTUDIESOFMATERIALS,TEXTURES,ANDCOLORTHATWOULDFORMASOUNDBASISFORLATERSPECIALIZATIONGROPIUSRECRUITEDANEXTRAORDINARYFACULTYTHATINCLUDEDANUMBEROFDISTINGUISHEDMODERNARTISTS,SUCHASPAULKLEE,WASSILYKANDINSKY,ANDLYONELFEININGER,ANDMANYOTHERDISTINGUISHEDTEACHERS,SUCHASJOSEFALBERS,LáSZLóMOHOLYNAGY,ANDMARCELBREUERIN1925ECONOMICANDPOLITICALPROBLEMSLEDTOTHECLOSINGOFTHEBAUHAUSATWEIMARANDITSRELOCATIONTOTHEINDUSTRIALCITYOFDESSAU,INANEWBUILDINGDESIGNEDBYGROPIUS169COMPLETEDIN1926,THEBAUHAUSBUILDINGWASANIMPRESSIVEGROUPINGTHATEMBODIEDBAUHAUSIDEALSINBOTHPLANANDAESTHETICEXPRESSIONTHEMOSTSTRIKINGPARTOFTHECOMPLEXWASAFOURSTORYBLOCKDEVOTEDTOWORKSHOPSWHERESTUDENTSCOULDACTUALLYPRODUCE,ATLEASTINPROTOTYPE,THEOBJECTSTHATTHEYDESIGNEDPRINTEDMATERIALS,WOVENTEXTILES,FURNITURE,CERAMICS,LAMPS,METALOBJECTS,STAGESCENERY,ANDCOSTUMESWEREALLTURNEDOUTINTHEWORKSHOPSAND,WHENEVERPOSSIBLE,MANUFACTURERSWEREPERSUADEDTOTAKEONPRODUCTIONOFBAUHAUSDESIGNSABRIDGEACROSSAPUBLICSTREETCONTAINEDALIBRARYANDOFFICESANDFORMEDALINKTOACLASSROOMBLOCKALOWLINKELEMENTCONTAINEDANAUDITORIUMANDDININGHALLTHISLEDTOASMALLDORMITORYUNITWHEREADVANCEDSTUDENTSHADSTUDIOBEDROOMS,MAKINGITPOSSIBLEFORTHEMTOLIVEFULLTIMEWITHINTHESCHOOLTHESTRIKINGAPPEARANCEOFTHEBAUHAUSBUILDINGRESULTEDFROMTHETHREESTORYHIGHGLASSCURTAINWALLSOFTHESHOPBLOCK,THEAUSTERELYORNAMENTFREEWHITEWALLSOFTHEOTHERWINGSWITHTHEIRLARGERIBBONSOFGLASSWINDOWS,AND,FORTHEDORMITORY,TINYPROJECTINGBALCONIESWITHTUBULARRAILINGSTHEFORMOFTHEBUILDINGWASDERIVEDFROMITSPLANTHEROOFSWEREFLATINACCORDANCEWITHMODERNINDUSTRIALPRACTICETHERESULTINGAPPEARANCEWASSTERNLYFUNCTIONALASSHOCKINGLYDISTURBINGTOTRADITIONALISTSASITWASEXCITINGTOTHENEWGENERATIONOFMODERNISTSTHEBAUHAUSBUILDINGANDALLSIMILARMODERNWORKSWEREDESCRIBEDASBEINGINTHEINTERNATIONALSTYLEBYTHEHISTORIANANDCRITICHENRYRUSSELLHITCHCOCKWHENHEWITHPHILIPJOHNSONORGANIZEDANEXHIBITIONOFSUCHWORKIN1932ATTHEMUSEUMOFMODERNARTINNEWYORKTHETERMREFLECTSTHEFACTTHATMODERNISMWASNOTMARKEDBYTHESTRONGNATIONALDIFFERENCESTYPICALOFEARLIERDESIGNHISTORYASRELATEDWORKBEGANTOAPPEARINFRANCE,ITALY,BRITAIN,ANDTHESCANDINAVIANCOUNTRIES,ITBECAMECLEARTHATSUCHMODERNISMWASTRULYINTERNATIONALINTERIORSATTHEBAUHAUSWEREASSIMPLEANDFUNCTIONALASTHEEXTERIORGROPIUSDESIGNEDAREMARKABLEINTERIORFORTHEDIRECTOR’SOFFICE,ASTUDYINRECTILINEARGEOMETRICFORMFURNITUREANDLIGHTFIXTURESDESIGNEDBYVARIOUSBAUHAUSSTUDENTSANDINSTRUCTORSWEREUSEDWHEREVERPOSSIBLE,WHILETHEUSEOFWHITE,GRAY,ANDPRIMARYCOLORACCENTSSUGGESTEDTHEDESIGNOFTHEDESTIJLMOVEMENTTHEBAUHAUSCAMEUNDERFINANCIALPRESSURESAND,WITHTHEHOSTILITYTOWARDALLAVANTGARDEIDEASTHATMARKEDTHERISINGNAZIMOVEMENT,POLITICALPRESSURESASWELLGROPIUSRESIGNEDIN1928,TOBESUCCEEDEDBYHANNESMEYERAND,IN1930,BYMIESVANDERROHEWHENTHESCHOOLWASFINALLYFORCEDTOCLOSEIN1933,MANYSTUDENTSANDFACULTYMEMBERSLEFTGERMANYASREFUGEESTHEEMERGENCEOFMODERNISM336169WALTERGROPIUS,BAUHAUS,DESSAU,GERMANY,1926INTHEGROUNDFLOORPLANTHEWORKSHOPAREASAPPEARATTHELOWERLEFT,ANDTHELECTUREHALLANDDININGROOMEXTENDTOTHERIGHTABRIDGEATUPPERFLOORLEVELSCONNECTSTOTHECLASSROOMBLOCK,SHOWNABOVEASTREETPASSESUNDERTHEBRIDGEELEMENT,ANDTHEREAREENTRANCESTOTHEBUILDINGONBOTHSIDESC16INDD336C16INDD33611/4/201394315PM11/4/201394315PM
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簡介:本科畢業(yè)設(shè)計外文翻譯外文譯文題目噴油定時對柴油噴油定時對柴油/天然氣雙燃料發(fā)動機排放性影響天然氣雙燃料發(fā)動機排放性影響學院專業(yè)學號學生姓名學生姓名指導教師指導教師日期
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簡介:1本科畢業(yè)設(shè)計論文外文翻譯譯文譯文中國上市公司偏好股權(quán)融資非制度性因素國際商業(yè)管理雜志200910摘要本文把重點集中于中國上市公司的融資活動,運用西方融資理論,從非制度性因素方面,如融資成本、企業(yè)資產(chǎn)類型和質(zhì)量、盈利能力、行業(yè)因素、股權(quán)結(jié)構(gòu)因素、財務(wù)管理水平和社會文化,分析了中國上市公司傾向于股權(quán)融資的原因,并得出結(jié)論,股權(quán)融資偏好是上市公司根據(jù)中國融資環(huán)境的一種合理的選擇。最后,針對公司的股權(quán)融資偏好提出了一些簡明的建議。關(guān)鍵詞股權(quán)融資,非制度性因素,融資成本一、前言中國上市公司偏好于股權(quán)融資,根據(jù)中國證券報的數(shù)據(jù)顯示,1997年上市公司在資本市場的融資金額為9587億美元,其中股票融資的比例是725%,,在1998年和1999年比例分別為726%和723%,另一方面,債券融資的比例分別是178%,249%和251%。在這三年,股票融資的比例,在比中國發(fā)達的資本市場中卻在下跌。以美國為例,當美國企業(yè)需要的資金在資本市場上,于股權(quán)融資相比他們寧愿選擇債券融資。統(tǒng)計數(shù)據(jù)顯示,從1970年到1985年,美日企業(yè)債券融資占了境外融資的917%,比股權(quán)融資高很多。閻達五等發(fā)現(xiàn),大約中國3/4的上市公司偏好于股權(quán)融資。許多研究的學者認為,上市公司按以下順序進行外部融資第一個是股票基金,第二個是可轉(zhuǎn)換債券,三是短期債務(wù),最后一個是長期負債。許多研究人員通常分析我國上市公司偏好股權(quán)是由于我們國家的經(jīng)濟改革所帶來的制度性因素。他們認為,上市公司的融資活動違背了西方古典融資理論只是因為那些制度性原因。例如,優(yōu)序融資理論認為,當企業(yè)需要資金時,他們首先應(yīng)該轉(zhuǎn)向內(nèi)部資金(折舊和留存收益),然后再進行債權(quán)融資,最后的選擇是股票融資。在這篇文章中,筆者認為,這是因為具體的金融環(huán)境激活了企業(yè)的這種偏好,并結(jié)合了非制度性因素和西方金融理論,嘗試解釋股權(quán)融資偏好的原因。二、上市公司的融資成本和股權(quán)融資偏好1關(guān),如果企業(yè)有更無形的資產(chǎn),更多低質(zhì)量的資產(chǎn),這將擁有較低的流動性和較低的資產(chǎn)抵押價值。當這類企業(yè)面臨著很大的金融風險時,就沒有辦法來解決其資產(chǎn)出售的問題。此外,因為對抵押貸款資產(chǎn)轉(zhuǎn)變成現(xiàn)金的能力的關(guān)注,債權(quán)人將提高利率水平,降低金融合約其他項目的債務(wù)人規(guī)則,這些都將提高代理成本和降低公司價值。美國高通公司是無線數(shù)據(jù)和通信服務(wù)供應(yīng)商,它是CDMA的發(fā)明者和用戶,也占據(jù)了HDR技術(shù)。2000年3月底,其股票的市場價值在1120億美元,但長期負債的數(shù)量是零。為什么呢原因可能是有一些在市場上擁有類似技術(shù)的競爭對手和高通公司管理層采取保守態(tài)度的融資活動。但最重要的因素可能是高通公司擁有大量具有較低質(zhì)量的可兌換無形資產(chǎn)將,它沒有足夠的資金來支付其債務(wù)時,公司的價值會下降。在中國,許多上市公司是由國有企業(yè)改造而來的。在轉(zhuǎn)型中,上市企業(yè)接管了國有企業(yè)的高效優(yōu)質(zhì)資產(chǎn),但隨著我國經(jīng)濟的發(fā)展,有些項目未能配合市場供求下降相應(yīng)資產(chǎn)價值。另一方面,新的高科技公司也有許多無形的資產(chǎn)。國有企業(yè)和高科技公司是資本市場的大部分地區(qū)。我們可以得出結(jié)論,上市公司的資產(chǎn)質(zhì)量卻很低。這一點是P/B指數(shù)(股價與賬面價值)支持的,這通常作為可以衡量的上市公司的資產(chǎn)質(zhì)量最重要的指標。據(jù)深圳證券信息公司的統(tǒng)計數(shù)據(jù),截至到2003年11月14日,共有412個公司的P/B小于2,占在中國發(fā)行A股的上市公司的比例的30%,其中,有150家公司的P/B小于153,而股市的加權(quán)平均P/B為242。資產(chǎn)質(zhì)量低意味著債務(wù)資金會帶來更多的成本,并降低上市公司的總價值。因此,在中國進行外部融資是,上市公司更傾向于股權(quán)。四、盈利能力和股權(quán)融資偏好財務(wù)杠桿理論告訴我們,在公司利潤的小變化可能使公司的每股收益發(fā)生巨大變化。就像杠桿,我們可以通過使用它擴增行動。債券融資可以充分利用這個作用,這些公司有較高的盈利水平將得到更高的每股收益水平,因為債券資本產(chǎn)生的利息為股東提供的利潤比股東應(yīng)當支付的更多。相反,這些公司的低盈利率會降低債券的每股盈利水平,因為債券不能產(chǎn)生股東履行清償?shù)睦嫘枨髞頋M足足夠的利潤。1999年,愛迪生國際公司具有穩(wěn)定的客戶量和許多無形的資產(chǎn),這些提供了高層次的盈利能力來獲得債務(wù)資金,其債務(wù)占其總資產(chǎn)的672%。在發(fā)達國家或地區(qū)的上市公司始終有高盈利水平。以美國為例,在美國資本市場有許多
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上傳時間:2024-03-12
頁數(shù): 9
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簡介:外文文獻翻譯材料(2010屆)屆)瑞士社會健康保險共同支付瑞士社會健康保險共同支付學生姓名學生姓名學號院系醫(yī)學院專業(yè)公共事業(yè)管理公共事業(yè)管理衛(wèi)生事業(yè)管理衛(wèi)生事業(yè)管理指導教師指導教師填寫日期填寫日期CHARACTERISTICSOFTHESWISSHEALTHINSURANCESYSTEMINSWITZERLAND,100PERCENTOFTHEPOPULATIONISENROLLEDINTHESTATUTORYBASICHEALTHINSURANCESYSTEMINTHECOMPLEMENTARYPRIVATEINSURANCESECTOR,THEEQUIVALENCEPRINCIPLEHOLDS–THEINSUREDPAYRISKEQUIVALENTPREMIUMSBYCOMPARISON,COMMUNITYRATINGAPPLIESINSOCIALHEALTHINSURANCE,IEEVERYPERSONWITHINASICKNESSFUNDPAYSTHESAMEPREMIUMIRRESPECTIVEOFHIS/HERRISKTHISIMPLIESTHATTHESOCALLEDGOODRISKSPERSONSWHOSEPAYMENTSEXCEEDTHEIREXPECTEDEXPENDISUBSIDIZETHEBADRISKSPERSONSWITHPAYMENTSBELOWTHEEXPECTEDEXPENDITUREWITHTHEGIVENHEALTHCAREEXPENDITUREPROFILES,COMMUNITYRATINGMEANSFORINSTANCETHATTHEYOUNGSUBSIDIZETHEOLDANDTHATMENSUBSIDIZEWOMENINCONTRASTTOGERMANYANDOTHERCOUNTRIES,SWITZERLANDDOESNOTIMPOSEANYSUBSTANTIALINTERREGIONALREDISTRIBUTIONINFINANCINGHEALTHCAREPREMIUMSAREDIFFERENTIATEDACCORDINGTOREGIONALDIFFERENCESINHEALTHCAREEXPENDITUREFURTHERMORE,CONTRIBUTIONSTOHEALTHINSURANCEARENOTPAIDFROMTHEPAYROLLBUTFUNCTIONASINOTHERINSURANCESECTORSEVERYINDIVIDUAL–ADULT,ADOLESCENTORCHILD–THEREFOREPAYSHIS/HEROWNPREMIUMNEVERTHELESS,LOWINCOMEPERSONSRECEIVEASUBSIDYFROMTHELOCALGOVERNMENTASWELLASFROMTHEFEDERALSTATETOPAYFORHEALTHINSURANCETHEAVERAGEHEALTHINSURANCEPREMIUMISAROUND€170PERMONTH
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簡介:畢業(yè)設(shè)計論文外文資料翻譯題目ASPNET概述概述院系名稱院系名稱信息科學與工程學院信息科學與工程學院專業(yè)班級專業(yè)班級計算機科學與技術(shù)計算機科學與技術(shù)05級6班學生姓名學生姓名學號號指導教師指導教師教師職稱教師職稱起止時間起止時間地點附件件1外文資料翻譯譯文;2外文原文。指導教師評語外文資料的選擇與畢業(yè)設(shè)計內(nèi)容密切相關(guān),文章具外文資料的選擇與畢業(yè)設(shè)計內(nèi)容密切相關(guān),文章具有一定的難度,但譯文能夠較好的表達出原文的思想。專業(yè)術(shù)語運用比有一定的難度,但譯文能夠較好的表達出原文的思想。專業(yè)術(shù)語運用比較準確,語句通順,文字數(shù)量符合要求。不足之處在于個別語句的翻譯較準確,語句通順,文字數(shù)量符合要求。不足之處在于個別語句的翻譯缺乏潤色,有些牽強。總之,譯文符合要求,反映出學生具有較好的專缺乏潤色,有些牽強??傊?,譯文符合要求,反映出學生具有較好的專ASPNET概述概述當ASP第一次發(fā)布時,WEB編程還比較困難,因為需要IIS來處理ASP頁。后來,ASPNET20和VISUALSTUDIO?2005通過引入網(wǎng)站開發(fā)模型使一切工作都變得容易了。借助該網(wǎng)站模型,您不必在VISUALSTUDIO中創(chuàng)建新項目,而是可以指向一個目錄并開始編寫網(wǎng)頁和代碼。此外,您還可以使用內(nèi)置的ASPNETDEVELOPMENTSERVER快速測試站點,ASPNETDEVELOPMENTSERVER將ASPNET寄宿在一個本地進程中,并消除了必須安裝IIS才能進行開發(fā)這一先決條件。下面從不同的方面來介紹ASPNET20技術(shù)。1NET類庫類庫ASPNET是微軟NETFRAMEWORK整體的一部分,它包含一組大量編程用的類,滿足各種編程需要。因為VISUALBASIC、JSCRIPT和C這些編程語言的很多功能具有重疊性。舉例來說,對于每一種語言,你必須包括存取文件系統(tǒng)、與數(shù)據(jù)庫協(xié)同工作和操作字符串的方法。此外,這些語言包含相似的編程構(gòu)造。都能夠使用循環(huán)語句和條件語句。即使用VISUALBASIC寫的條件語句的語法和用C的不一樣,程序的功能也是相同的。對于多種語言來說維持這一功能需要很大的工作量。那么對所有的語言創(chuàng)建這種功能一次,然后把這個功能用在每一種語言中豈不是更容易。然而NET類庫不完全是那樣。它含有大量的滿足編程需要的類。舉例來說,NET類庫不僅包含處理數(shù)據(jù)庫訪問的類和文件協(xié)同工作,操作文本和生成圖像,而且還包含更多特殊的類用在正則表達式和處理WEB協(xié)議。此外NETFRAMEWORK,也包含支持所有的基本變量數(shù)據(jù)類型的類,比如字符串、整型、字節(jié)型、字符型和數(shù)組。NETFRAMEWORK是龐大的。它包含數(shù)以千計的類。超過3,400幸運地是,類不是簡單的堆在一起。NETFRAMEWORK的類被組織成有層次結(jié)構(gòu)的命名空間。一個命名空間包含一組邏輯的類。舉例來說,涉及到與文件系統(tǒng)協(xié)同工作的類就集合在SYSTEMIO命名空間中。命名空間被組織成一個層次結(jié)構(gòu)一棵邏輯樹。樹根就是SYSTEM命名空間。這個命名空間包含基本的數(shù)據(jù)類型的所有的類,例如字符串、數(shù)組,還包含提供隨機數(shù)字和日期的類。你通過完整的類的命名空間能唯一識別任何的類在NETFRAMEWORK中的位置。例如,指定找到一個THEFILECLASS類,按如下操作SYSTEMIO文件
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簡介:0南京郵電大學畢業(yè)設(shè)計論文外文資料翻譯學院經(jīng)濟與管理學院專業(yè)學生姓名班級學號外文出處南郵外文數(shù)據(jù)庫附件1外文資料翻譯譯文;2外文原文指導教師評價1.翻譯內(nèi)容與課題的結(jié)合度□優(yōu)√良□中□差2.翻譯內(nèi)容的準確、流暢□優(yōu)√良□中□差3.專業(yè)詞匯翻譯的準確性□優(yōu)□良√中□差4.翻譯字符數(shù)是否符合規(guī)定要求√符合□不符合總評為良。指導教師簽名洪小娟2012年5月3日2定義定義埃德蒙茲2001所界定的復雜性復雜的是,在給定的語言中這難以制定的整體行為,即使給予了相當完整的信息,其原子組件和它們的相互關(guān)系的模型屬性。112112復雜網(wǎng)絡(luò)復雜網(wǎng)絡(luò)網(wǎng)絡(luò)至少早在18世紀已經(jīng)正式出現(xiàn),歐拉在他試圖解決著名的哥尼斯堡橋問題的圖論研究中首先出現(xiàn)。圖論的概念已被廣泛應(yīng)用,因為在這里有一些手段聯(lián)系著實體集的各個學科。調(diào)查這些網(wǎng)絡(luò)結(jié)構(gòu)的特點導致了一系列基礎(chǔ)的分析現(xiàn)代圖理論的解決措施。社會網(wǎng)絡(luò)分析工具的應(yīng)用可以追溯到20世紀初(斯科特,1991),從那以后,社會網(wǎng)絡(luò)分析的規(guī)則SNA成為了網(wǎng)絡(luò)研究涉及的作用物間個人、組織等開發(fā)的一種度量,針對社會角色和相互作用物的不同方面。我們將在第2節(jié)討論SNA。1212典型的復雜網(wǎng)絡(luò)和特點典型的復雜網(wǎng)絡(luò)和特點我們目前只是簡要概述了一個典型復雜網(wǎng)絡(luò)的特點和其顯著特征。一個詳盡的文獻是有用的,尤其是BARABáSI(2001年)和瓦茨(2003提供了一個全面的網(wǎng)絡(luò)解釋。121121隨機圖理論隨機圖理論其中最早嘗試研究這些所謂“復雜網(wǎng)絡(luò)”的行為追溯到隨機圖理論的開創(chuàng)性的工作,在20世紀50年代開始的保羅鄂爾多斯和阿爾弗雷德萊利的ER模型,基本ER模型需要通過選擇隨機等,由此產(chǎn)生的網(wǎng)絡(luò)是從空間的N條邊連接N個節(jié)點。在隨機圖(足夠大)圖表中每個節(jié)點有相同概率,給定線路的概率P并不小,隨機的直徑通常是小直徑增加對數(shù),作為一個隨機圖的擴展。122122PARETOPARETO分布及自組織臨界性分布及自組織臨界性假設(shè)使用統(tǒng)計方法,在許多情況下,標準偏差和數(shù)據(jù)分布是已知和穩(wěn)定的。在許多情況下,人們發(fā)現(xiàn),仿真結(jié)果生成的數(shù)據(jù)具有肥尾和薄高峰被稱為LEPTOKURTOSIS特點。其中一個復雜網(wǎng)絡(luò)的特點是外觀的冪律分布在很多地方。非正式的,這意味著大多數(shù)網(wǎng)絡(luò)連接節(jié)點相對很少也相對較小反之亦然。所謂的冪律(S)源于對帕累托分布、專業(yè)化的帕累托原理,命名VIFREDO帕累托維基百科,2005。概率密度分布函數(shù)的定義為巴泰勒米(2003)討論了兩個參數(shù)XM和K作為分布參數(shù),如果形狀(峰度)參數(shù)KI(0,2K值≤1,平均是無限的,而對于K≤2。方差是有限的。圖1顯示了的薄峰度,這是分布的特點。我們在這里的目的是影響,而不是討論提出一種分析性能的分布,可以發(fā)現(xiàn)任何標準的文本在隨機分布。這些特點為進一步的研究基礎(chǔ)模型和現(xiàn)象的的處理提供線索。我們在后面將回到這個問題上。另一個問題就是“如果這些系統(tǒng)是模擬系統(tǒng)平衡市場所描述的經(jīng)濟理論,規(guī)范效用最大化代理商將不支持大的分析分布式系統(tǒng)性能,”。這進一步鼓勵了在統(tǒng)計簽名驗證相關(guān)理論。事實上,更高,更薄的頻率分布與相應(yīng)的正態(tài)分布,即
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簡介:南京理工大學紫金學院畢業(yè)設(shè)計論文外文資料翻譯系系電子工程與光電技術(shù)專業(yè)業(yè)電子信息工程姓名名袁箭陽學號號080401264外文出處外文出處LARGEANDSMALLDATAACQUISITIONSYSTEMSFUSIONENGINEERINGANDDESIGN,199943363369附件件1外文資料翻譯譯文;2外文原文。指導教師評語外文資料翻譯內(nèi)容基本正確,語句較通順,反映了該學生具有一定的外文閱讀能力和理解能力。成績良用外文寫附件1外文資料翻譯譯文用于噴氣機的大小型的數(shù)據(jù)采集系統(tǒng)用于噴氣機的大小型的數(shù)據(jù)采集系統(tǒng)摘要摘要大型和小型的數(shù)據(jù)采集系統(tǒng)在大部分物理實驗中得到應(yīng)用,比如噴氣機。這篇論文描述了集中采集和觸發(fā)系統(tǒng)(CATS),它在診斷學方面提供了同步的高速數(shù)據(jù)采集技術(shù),同時也介紹了基于商業(yè)電腦采集技術(shù)軟件和硬件的許多更小型的噴氣機基礎(chǔ)設(shè)施的集成。相對于嵌入式總線系統(tǒng)來說,這種計算機系統(tǒng)成本更低,程序調(diào)試時間更短。1999噴氣機聯(lián)合企業(yè)。由ELSEVIERSCIENCE出版,版權(quán)所有。關(guān)鍵字關(guān)鍵字數(shù)據(jù)采集系統(tǒng);集中采集和觸發(fā)系統(tǒng);嵌入式總線系統(tǒng)1.引言引言數(shù)據(jù)采集系統(tǒng)通常由總線技術(shù)建立而來,比如計算機輔助測量與控制或VME,這基本上通過嵌入式處理器和工業(yè)模塊實現(xiàn)。這些東西通過總線接口或網(wǎng)絡(luò)集成到中央計算機系統(tǒng)中。這篇論文描述了應(yīng)用在噴氣機上的兩種不同的創(chuàng)新的數(shù)據(jù)采集方法。第一種方法是集中采集和觸發(fā)系統(tǒng)(CATS)。這種系統(tǒng)在近三年內(nèi)得以發(fā)展,如今能夠為大量的先進的采集數(shù)據(jù)提供實時的數(shù)據(jù)選擇和分析。并行處理技術(shù)的應(yīng)用使得寬脈沖的智能觸發(fā)采集系統(tǒng)得以發(fā)展,比如ITER,它有很多的數(shù)據(jù)發(fā)生通道,使得連續(xù)或者在預(yù)定時間窗口內(nèi)記錄數(shù)據(jù)是不可能的。第二種方法是基于DOS或WINDOWS操作系統(tǒng)的標準計算機硬件,它越來越廣泛的應(yīng)用在噴氣機中,且成本比較低,通過使用商業(yè)硬件或軟件,這種方法程序調(diào)試時間短,也更容易維護。一個簡單的、標準的基礎(chǔ)設(shè)施已經(jīng)可以被應(yīng)用在數(shù)據(jù)采集中,它允許數(shù)據(jù)從這些系統(tǒng)到中央數(shù)據(jù)倉庫中。22中央采集和觸發(fā)系統(tǒng)中央采集和觸發(fā)系統(tǒng)在磁流體動力學和其他等離子體現(xiàn)象的研究中,經(jīng)驗表明為數(shù)據(jù)采集設(shè)置固定的時間窗口是不可能的。在單脈沖期間隨機發(fā)生的快速事件以及記錄這個事件
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簡介:688IEEETRANSACTIONSONNEURALNETWORKS,VOL14,NO3,MAY2003FPGAIMPLEMENTATIONOFAPULSEDENSITYNEURALNETWORKWITHLEARNINGABILITYUSINGSIMULTANEOUSPERTURBATIONYUTAKAMAEDAANDTOSHIKITADAABSTRACTHARDWAREREALIZATIONISVERYIMPORTANTWHENCONSIDERINGWIDERAPPLICATIONSOFNEURALNETWORKSNNSINPARTICULAR,HARDWARENNSWITHALEARNINGABILITYAREINTRIGUINGINTHESENETWORKS,THELEARNINGSCHEMEISOFMUCHINTEREST,WITHTHEBACKPROPAGATIONMETHODBEINGWIDELYUSEDAGRADIENTTYPEOFLEARNINGRULEISNOTEASYTOREALIZEINANELECTRONICSYSTEM,SINCECALCULATIONOFTHEGRADIENTSFORALLWEIGHTSINTHENETWORKISVERYDIFFICULTMORESUITABLEISTHESIMULTANEOUSPERTURBATIONMETHOD,SINCETHELEARNINGRULEREQUIRESONLYFORWARDOPERATIONSOFTHENETWORKTOMODIFYWEIGHTSUNLIKETHEBACKPROPAGATIONMETHODINADDITION,PULSEDENSITYNNSYSTEMSHAVESOMEPROMISINGPROPERTIES,ASTHEYAREROBUSTTONOISYSITUATIONSANDCANHANDLEANALOGQUANTITIESBASEDONTHEDIGITALCIRCUITSINTHISPAPER,WEDESCRIBEAFIELDPROGRAMMABLEGATEARRAYREALIZATIONOFAPULSEDENSITYNNUSINGTHESIMULTANEOUSPERTURBATIONMETHODASTHELEARNINGSCHEMEWECONFIRMTHEVIABILITYOFTHEDESIGNANDTHEOPERATIONOFTHEACTUALNNSYSTEMTHROUGHSOMEEXAMPLESINDEXTERMSFIELDPROGRAMMABLEGATEARRAYFPGA,LEARNINGABILITY,NEURALNETWORKSNNS,PULSEDENSITY,SIMULTANEOUSPERTURBATIONIINTRODUCTIONNEURALNETWORKSNNSAREWIDELYUSEDINANUMBEROFAPPLICATIONSINWHICHTHENNSAREUSUALLYIMPLEMENTEDASASOFTWAREPROGRAMONANORDINARYDIGITALCOMPUTERHOWEVER,SOFTWAREIMPLEMENTATIONSCANNOTUTILIZETHEESSENTIALPROPERTYOFPARALLELISMFOUNDINBIOLOGICALNNSINTHISRESPECT,IMPLEMENTATIONOFNNSUSINGHARDWAREELEMENTSSUCHASVERYLARGESCALEINTEGRATIONVLSIISBENEFICIALWHENCONSIDERINGTHEHARDWAREIMPLEMENTATIONOFANNN,REALIZATIONOFTHELEARNINGMECHANISMASAHARDWARESYSTEMISANIMPORTANTANDDIFFICULTISSUE1ASWEWELLKNOW,THEBACKPROPAGATIONMETHODISCOMMONLYUSEDHOWEVER,REALIZATIONOFTHEBACKPROPAGATIONMETHODASANELECTRONICSYSTEMISVERYDIFFICULT,CONSIDERINGWIRINGFORMODIFYINGQUANTITIESTOALLWEIGHTS,CALCULATIONOFTHEDERIVATIVEOFTHESIGMOIDFUNCTION,ANDSOONTHUS,ITISPARTICULARLYDIFFICULTTOIMPLEMENTLARGESCALENNSWITHLEARNINGABILITYVIATHEGRADIENTMETHODBECAUSEOFTHECOMPLEXITYOFTHEMECHANISMTHATDERIVESTHEGRADIENTFROMTHISPOINTOFVIEW,WEMUSTTRYTOFINDALEARNINGRULETHATISEASYTOREALIZETHESIMULTANEOUSPERTURBATIONMETHODWASINTRODUCEDBYSPALL2,3,ALESPECTORETAL4,ANDCAUWENBERGHS5MAEDAALSOINDEPENDENTLYPROPOSEDALEARNINGRULEOFNNSUSINGSIMULTANEOUSPERTURBATIONANDREPORTEDAFEASIBILITYOFMANUSCRIPTRECEIVEDOCTOBER18,2001REVISEDMARCH4,2002ANDJANUARY3,2003THISWORKWASSUPPORTEDINPARTBYKANSAIUNIVERSITYHIGHTECHNOLOGYRESEARCHCENTERTHEAUTHORSAREWITHTHEDEPARTMENTOFELECTRICALENGINEERING,FACULTYOFENGINEERING,KANSAIUNIVERSITY,OSAKA5648680,JAPANDIGITALOBJECTIDENTIFIER101109/TNN2003811357THELEARNINGRULE6–8ATTHESAMETIME,THEMERITOFTHELEARNINGRULEWASDEMONSTRATEDINVLSIIMPLEMENTATIONOFANALOGNNS9,10THEADVANTAGEOFTHESIMULTANEOUSPERTURBATIONOPTIMIZATIONMETHODISITSSIMPLICITYTHEMETHODCANESTIMATETHEGRADIENTUSINGONLYVALUESOFTHEERRORFUNCTIONTHEREFORE,IMPLEMENTATIONOFTHISLEARNINGRULEISRELATIVELYEASYCOMPAREDTOTHATOFOTHERLEARNINGRULES,BECAUSEITDOESNOTHAVETOTAKETHEERRORBACKPROPAGATIONCIRCUITINTOACCOUNTCERTAINPULSETECHNIQUES,SUCHASPULSEWIDTHORPULSESTREAM,HAVEALSOBEENINVESTIGATEDTOIMPLEMENTARTIFICIALNNSFOREXAMPLE,ELMASRYETALREPORTEDANEFFICIENTIMPLEMENTATIONOFARTIFICIALNNSUSINGACURRENTMODEPULSEWIDTHMODULATIONARTIFICIALNN11MOREOVER,MURRAYETALPROPOSEDAVLSINNUSINGANALOGANDDIGITALTECHNIQUES12INPARTICULAR,PULSEDENSITYNNSHAVEFASCINATINGPROPERTIESFOREXAMPLE,PULSESYSTEMSAREINVULNERABLETONOISYCONDITIONSMOREOVER,PULSEDENSITYSYSTEMSCANHANDLEQUANTIZEDANALOGVALUESBASEDONTHEDIGITALCIRCUIT13BASEDONTHESEFEATURES,HIKAWAREPORTEDAFREQUENCYBASEDNNUSINGTHEBACKPROPAGATION14IN14,THEORDINARYBACKPROPAGATIONMETHODISAPPLIEDTOAPULSEDENSITYNNHOWEVER,ITSEEMSDIFFICULTTOEMPLOYTHEBACKPROPAGATIONMETHODFORAPULSEDENSITYSYSTEMACTUALLY,NNSYSTEMDESCRIBEDIN14HASTOCOMPLETETHEERRORPROPAGATIONMECHANISMBASEDONTHEPULSEDENSITY,INWHICHCASETHECIRCUITDESIGNBECOMESCOMPLEXCOMPAREDWITHTHESIMULTANEOUSPERTURBATIONMETHODRECENTLY,FIELDPROGRAMMABLEGATEARRAYSFPGASHAVEBEENUSEDINMANYCOMMERCIALFIELDSBECAUSEOFTHEIRRECONFIGURATIONPROPERTIESANDFLEXIBILITY15FPGASALSOSEEMTOBEPROMISINGDEVICESFORIMPLEMENTINGNNS,INCOMPARISONWITHORDINARYSOFTWAREIMPLEMENTATIONSVHDLISAVERYPOPULARHARDWAREDESCRIPTIONLANGUAGEHDLFORDESCRIBINGORDESIGNINGDIGITALCIRCUITSINTHEFUNDAMENTALDESIGNOFTHISRESEARCH,HDLISUSEDCOMBININGAPULSEDENSITYSYSTEMWITHTHESIMULTANEOUSPERTURBATIONMETHOD,WECANEASILYDESIGNANALOGHARDWARENNSYSTEMSWITHLEARNINGCAPABILITYSOMEOFTHEFEATURESOFAPULSEDENSITYNNSYSTEMUSINGFPGACANBESUMMARIZEDASFOLLOWS1HARDWARECANTAKEADVANTAGEOFPARALLELISM2SIMULTANEOUSPERTURBATIONLEARNINGRULEISVERYSIMPLE3ANALOGNNSYSTEMISREALIZEDBASEDONDIGITALCIRCUITS4DIGITALDESIGNTECHNOLOGYUSEDISSUPPORTEDBYELECTRONICDESIGNAUTOMATIONAND5PULSEDENSITYNNSARENOTAFFECTEDBYNOISYSITUATIONSIISIMULTANEOUSPERTURBATIONLEARNINGRULEDETAILSOFTHESIMULTANEOUSPERTURBATIONMETHODASALEARNINGRULEOFNNSHAVEBEENDESCRIBEDPREVIOUSLY6–9,13ANDAREREITERATEDINTHISSECTION10459227/031700?2003IEEE690IEEETRANSACTIONSONNEURALNETWORKS,VOL14,NO3,MAY2003FIG2WEIGHTUNITFIG3WEIGHTMODIFICATIONPARTUNITANDCARRIESOUTADDITIONORSUB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簡介:1INTRODUCTIONVITAMINCOCCURSINDIFFERENTCONCENTRATIONSINAVARIETYOFNATURALSAMPLESITISADDEDTOSEVERALPHARMACEUTICALPRODUCTSASANESSENTIALINGREDIENT,ASTABILIZERFORVITAMINBCOMPLEX,ANDASANANTIOXIDANTCONSEQUENTUPONITSDESIRABLEEFFECTS,ITISWIDELYUSEDINTHETREATMENTOFCERTAINDISEASESSUCHASSCURVY,COMMONCOLD,ANEMIA,HAEMORRHAGICDISORDERS,WOUNDHEALING,ANDEVENINFERTILITY,TOMENTIONSOMESTARKCASESITISCONSIDEREDESSENTIALFORTHEDEVELOPMENTANDREGENERATIONOFMUSCLES,BONES,TEETHANDSKINTHEINCREASINGUSEOFPHARMACEUTICALSANDOTHERNATURALSAMPLESCONTAININGVITAMINCHASMEANTTHATTHEPRACTICISINGCHEMISTSSHOULDDEVELOPANALYTICALPROCEDURESFORITSDETERMINATIONWHICHARESIMPLETOOPERATE,RAPID,ACCURATE,SENSITIVEANDSELECTIVETHEDESIRETODEVELOPMETHODSWITHIDEALCHARACTERISTICSHASRESULTEDALARGENUMBEROFPROCEDURESWITHVARYINGAPPLICABILITYMANYINSTRUMENTBASEDANALYSESINCLUDINGFLUOROMETRY1–4,HPLC5–10,POLAROGRAPHY11–13ANDENZYMATIC14,15METHODSAREREPORTEDINTHELITERATUREBUTDUETOTHEIRINHERENTLIMITATIONS,THESETECHNIQUESARENOTCOMMONLYUSEDFORROUTINEANALYSESHOWEVER,PHOTOMETRICMETHODSAREPARTICULARLYATTRACTIVEBECAUSEOFTHEIRSPEEDANDSIMPLICITYCONSEQUENTLY,ALARGENUMBEROFSUCHPROCEDURESHAVEBEENDEVELOPEDFORTHEDETERMINATIONOFASCORBICACIDAATHOUGHSOMESHORTREVIEWS16–18HAVEBEENREPORTED,ACRITICALASSESSMENTOFTHESEMETHODSISDESIRABLETOEXAMINETHEIRSALIENTFEATURESANDUTILITYTHISREVIEWISANATTEMPTTOASSESSEXCLUSIVELYTHEEXISTINGSPECTROPHOTOMETRICMETHODSFORTHEDETERMINATIONOFVITAMINCASREGARDSTHEIRSIMPLICITY,RAPIDITY,BEER’SLAWRANGE,SENSITIVITY,SELECTIVITYANDAPPLICABILITYITISPRIMARILYBASEDONTHEINFORMATIONCOLLECTEDTHROUGHTHECHEMICALABSTRACTSFORTHEPERIOD1970TOMID19972RESULTSANDDISCUSSIONSEVERALDYESSUCHAS2,6DICHLOROPHENOLINDOPHENOLDCIP,DIMETHOXYDIQUINONEDMDQ,NINHYDRIN,FASTREDALSALTAND2′,7′DICHLOROFLUORESCEINETCHAVEBEENUSEDFORTHEDETERMINATIONOFVITAMINCAMONGTHESEDYES,DCIPHASBEENMOSTEXTENSIVELYSTUDIEDITISINCLUDEDINTHEOFFICIALTITRIMETRICMETHODSASREPORTEDINDIFFERENTPHARMACOPOEIAS19–21ANDITALSOFORMSTHEBASISOFMANYCOLORIMETRICMETHODSTHEBLUEDYEDCIPISREDUCEDTOTHECOLORLESSFORMONADDITIONOFASCORBICACIDASSHOWNINFIG1,BUTITGIVESAPINKCOLORTOTHEACIDICSOLUTIONSUSINGTHEDYE,ASCORBICACIDPRESENTINHUMANURINE22ANDPROCESSEDPOTATOES23HASBEENDETERMINEDTHEEXCESSDYECANBEEXTRACTEDWITHXYLENEORBUTANOL24MANYSUBSTANCESWHICHARECAPABLEOFREDUCINGTHEDYERESULTINGFROMTHEPREPARATIONANDPROCESSINGOFFOODSAMPLESINTERFEREFLOWDIALYSISPROPOSEDBYGARYETAL25ANDCONTINUOUSFLOWSYSTEMSHAVEBEENUSEDTOMONITORTHEDECREASEINABSORBANCEOFDCIPSUCHAUTOMATEDSYSTEMSAPPEARTOBEJUSTIFIEDONLYWHENROUTINEANALYSISOFALARGEANALYTICALSCIENCESOCTOBER1998,VOL14PHOTOMETRICMETHODSFORTHEDETERMINATIONOFVITAMINCSATYAPARYA?,MEENAKSHIMAHAJANANDPREETIJAINDEPARTMENTOFCHEMISTRY,KURUKSHETRAUNIVERSITY,KURUKSHETRA–136119,HARYANASTATE,INDIATHEIMPORTANCEOFVITAMINCTOTHEHUMANBODYISWIDELYACKNOWLEDGEDTHROUGHOUTTHEGLOBETHEDEFICIENCYOFTHISVITAMINLEADSTOVARIOUSDISEASESINVIEWOFITSIMPORTANCE,NUMEROUSMETHODSINCLUDINGSPECTROPHOTOMETRICONESHAVEBEENDEVELOPEDFORITSDETERMINATIONINPHARMACEUTICALS,FOODSANDBIOLOGICALSAMPLESACOMPREHENSIVEREVIEWOFTHEAVAILABLESPECTOPHOTOMETRICMETHODSFORTHEDETERMINATIONOFASCORBICACIDISPRESENTEDKEYWORDSVITAMINCDETERMINATION,SPECTROPHOTOMETRICMETHOD?TOWHOMCORRESPONDENCESHOULDBEADDRESSEDFIG1THEREDUCTIONOFDCIPWITHASCORBICACIDASCORBICACIDDCIPOXIDIZED,BLUEPINKDEHYDROASCORBICACIDDCIPREDUCED,COLORLESSANDTRINITROBENZENE47INTARTRATEBUFFERWHENSTUDIEDFORITSDETERMINATIONOVERTHECONCENTRATIONRANGES2–50AND0–125ΜGML–1OFASCORBICACIDRESPECTIVELYMETHANOLICSOLUTIONOFRESORCINOL48GIVESAPALEYELLOWCOLORΛMAX425NMWITHASCORBICACIDINHYDROCHLORICACIDMEDIUM,OBEYINGBEER’SLAWFOR80–400ΜGML–14CHLORO7NITROBENZOFURAZANE49FORMSABLUISHGREENCOLOREDSPECIESWITHASCORBICACIDINPRESENCEOF02MSODIUMHYDROXIDETHEABSORBANCEISMEASUREDAT582NMAFTERDILUTINGTHEREACTIONCONTENTSWITH50V/VAQUEOUSACETONESOLUTIONBEER’SLAWISOBEYEDINTHECONCENTRATIONRANGE5–20ΜGML–1THECOLOREDPRODUCTISSTABLEFOR30MINONLYWHENKEPTAWAYFROMDIRECTSUNLIGHTORARTIFICIALDAYLIGHTTHEMETHODISREPORTEDFREEFROMTHEINTERFERENCEOFALLOTHERVITAMINSANDMINERALSPRESENTINMULTIVITAMINPREPARATIONSANDCANBEAPPLIEDTOTHEANALYSISOFPHARMACEUTICALS,FRESHFRUITJUICESANDVEGETABLESHASHMIETAL50PROPOSEDAMETHODBASEDONTHEREACTIONOF2,3,5TRIPHENYLTETRAZOLIUMCHLORIDEWITHASCORBICACIDINALKALINEMEDIUMTHEPINKSOLUTIONISALLOWEDTOSTANDINTHEDARKFOR30MINAT25?CITOBEYSBEER’SLAWOVERTHERANGE5–25ΜGML–1SUGARS15ΜGML–1EXCEPTSUCROSEINTERFEREBYFORMINGASIMILARCOLORTOTHATOFTHEREAGENTRIBOFLAVIN,CYANOCOBALAMINANDFOLICACIDINTERFEREDUETOTHEIROWNCOLORBEUTLERETAL51,52INVESTIGATEDTHEUSEOFMETHYLTHIAZOLYLTETRAZOLIUMSALTINPRESENCEOFASCORBATEOXIDASEENZYMEAND34,5DIMETHYLTHIAZOLYL2YL2,5DIPHENYLTETRAZOLIUMCHLORIDEORBROMIDEINTHEPRESENCEOF5METHYLPHENAZINIUMMETHYLSULFATEELECTRONCARRIERATPH35FORTHEDETERMINATIONOFASCORBICACIDINFOODS,FRUITJUICESANDVEGETABLESJUICESTHESEREACTIONSINVOLVETHEFORMATIONOFFORMAZONΛMAX578NMTHEINTERFERENCEOFSULFURDIOXIDEREQUIRESTREATMENTWITHFORMALDEHYDE,ANDCOLORINTERFERENCEFROMDARKJUICESISREMOVEDBYDECOLORIZATIONWITH1POLYVINYLPOLYPYRROLIDONEBEFOREFILTRATIONSORBITOL,ALCOHOLANDOXALATEINTERFEREWITHTHEASCORBICACIDOXIDASEHOWEVER,THEEFFECT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下載積分: 10 賞幣
上傳時間:2024-03-13
頁數(shù): 10
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簡介:THISISTHEAUTHOR’SVERSIONOFAWORKTHATWASSUBMITTED/ACCEPTEDFORPUBLICATIONINTHEFOLLOWINGSOURCEJAMTSHO,LUNGTENINIOWA–FOREXAMPLE,DOORNINKETAL2003ANDWIPFETAL2003ASIMILARSTUDYONTHEUSAGEOFQUEENSLANDFRWSISONGOINGATTHEQUEENSLANDUNIVERSITYOFTECHNOLOGY,AUSTRALIAADEMONSTRATIONBRIDGECONSISTINGOFTHEFRWDECKANDREINFORCEDCONCRETESLABRCSPAVEMENTWASCONSTRUCTEDWITHINTHEROCKHAMPTONREGIONALCOUNCILRRCJURISDICTION,QUEENSLANDTHESERVICEABILITYLIMITSTATESOFTHEFRWRCSCOMPOSITEDECKSYSTEMISCRITICALASTHEFRWHASHADAHISTORYOFSERVICELOADCYCLESASARAILFREIGHTWAGONWHILSTTHERCSISACASTINSITUNEWCOMPONENTASTHEBRIDGEISSITUATEDINLOWVOLUMETRAFFICROADSNETWORKSINRRCFACTSHEET,2010,FATIGUEWASNOTCONSIDEREDTHEBRIDGEWASTESTEDFORITSPERFORMANCEPERFORMANCELOADTESTSAREGENERALLYCARRIEDOUTUSINGPREDETERMINEDSMALLERLOADSTHATAREWELLBELOWTHEULTIMATELOADLEVELANDHENCEARELOWRISKSMALLERTRUCKSLOADEDWITHAGGREGATE/SANDAREGENERALLYUSEDTHESETESTSAREACLASSOFNONDESTRUCTIVETESTINGANDPROVIDEINSIGHTINTOTHEBRIDGERESPONSETOTHEAPPLIEDLOADSCHAJESETAL2000ANDRYALL,2010ANDTHEDATAMAYALSOBEUSEDTOASSESSTHEDESIGNLOADBEHAVIOURUSINGCALIBRATEDANALYTICAL/NUMERICALMODELSRICHARDETAL2010SUCHTESTSAREPERFORMEDONTHEAGEINGBRIDGESTHATAREINSERVICESARAFANDNOWAK,1998TESTSAREALSOCARRIEDOUTONNEWLYCONSTRUCTEDBRIDGESTHATINCORPORATENOVELCONSTRUCTIONMATERIALSORDESIGNSTALLINGANDYOO,1993BOULLYANDSEMPLE,1997STONEETAL2001ANDJOURNALOFBRIDGEENGINEERINGSUBMITTEDMAY30,2011ACCEPTEDDECEMBER6,2011POSTEDAHEADOFPRINTDECEMBER8,2011DOI101061/ASCEBE194355920000357COPYRIGHT2011BYTHEAMERICANSOCIETYOFCIVILENGINEERS
下載積分: 10 賞幣
上傳時間:2024-03-13
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簡介:PROCEEDINGSWORLDGEOTHERMALCONGRESS2010BALI,INDONESIA,2529APRIL20101THERMOECONOMICOPTIMIZATIONOFGEOTHERMALFLASHSTEAMPOWERPLANTSMEHDIZEYGHAMIENDOFPOONAKEBAKHTARIBLVD,SHAHRKEGHODS,POBOX14665/517TEHRAN\IRANMZEYGHAMINRIACIRKEYWORDSTHERMOECONOMICMODELING,SINGLEFLASH,DOUBLESFLASH,OPTIMIZATIONABSTRACTFLASHSTEAMPOWERPLANTSARERELATIVELYACOMMONMETHODUSEDTOCONVERTTHEGEOTHERMALENERGYINTOELECTRICITYWHENPRODUCTIONWELLSPRODUCEAMIXTUREOFSTEAMANDLIQUIDINAGEOTHERMALSYSTEMINCOMPARISONTOTHESINGLEFLASHSYSTEM,THEDOUBLEFLASHSTEAMPOWERPLANTGENERATESMOREPOWERFROMGEOTHERMALFLUIDATTHESAMECONDITIONSHOWEVER,ELECTRICITYGENERATIONCOSTSAREHIGHERFORDOUBLEFLASHPLANTSATHERMOECONOMICOPTIMIZATIONMODELISPRESENTEDINTHISPAPERASTHEGENERATIONCOSTSOFSINGLEANDDOUBLEFLASHSTEAMPOWERPLANTSBYCONSIDERINGTHEPRESSURESINTHESEPARATORANDFLASHVESSELONLYINADOUBLEFLASHPLANTASTHEINDEPENDENTVARIABLESINTHEOBJECTIVEFUNCTIONANDUSINGNUMERICALSEARCHMETHODSGOLDENRATIOANDNELDERMEAD,THEMINIMUMPOWERGENERATIONCOSTWASCALCULATEDATDIFFERENTGEOFLUIDCONDITIONSFOREITHERSINGLEORDOUBLEFLASHSTEAMPOWERPLANTSTHEANALYSISWASCARRIEDOUTFORPLANTSIZESFROM5TO150MWTHEECONOMYOFSCALEWASTAKENINTOACCOUNTFORINVESTMENTCOSTSANDOPERATIONMAINTENANCECOSTSTHERESULTSFORMINIMUMGENERATIONCOSTANDNETPOWEROUTPUTUSINGSINGLEANDDOUBLEFLASHGEOTHERMALPOWERPLANTSISPRESENTEDFORDIFFERENTGEOFLUIDTEMPERATURESANDFLOWRATES1INTRODUCTIONGEOTHERMALENERGYISTHENATURALHEATENERGYWITHINTHEEARTHTHISENERGYCANBERECOVEREDINSPECIFICAREASINHOTWATERORSTEAMHYDROTHERMALSYSTEMSARENATURALGEOTHERMALSOURCESINWHICHWATERISHEATEDINCONTACTWITHHOTROCKSBENEATHLAYERSOFTHEEARTHSSURFACEANDTURNSTOSTEAMVAPORDOMINATEDSYSTEMSORHOTWATERLIQUIDDOMINATEDSYSTEMSELWAKIL,1985INHYDROTHERMALSYSTEMS,ITISPOSSIBLETOEXTRACTTHEHOTGEOTHERMALFLUIDBYDRILLINGWELLSTOSUITABLEDEPTHSINPROPERPLACESTHEFLOWCOULDEITHERBENATURALFLOWUNDERITSOWNPRESSUREORPUMPEDTOTHESURFACEINLIQUIDDOMINATEDSYSTEMS,PRESSUREDROPINTHEWELLTURNSSOMELIQUIDSINTOVAPOR,WHICHRESULTSINALOWQUALITY,TWOPHASEMIXTUREATTHEWELLHEADUSINGFLASHSTEAMPOWERPLANTSISONEOFTHECOMMONWAYSTOCONVERTTHEEXTRACTEDHEATTOMECHANICALPOWERANDELECTRICITYSINGLEFLASHSTEAMPOWERPLANTSAREOFTENTHEFIRSTPOWERPLANTSINSTALLEDATNEWLYDEVELOPEDLIQUIDDOMINATEDGEOTHERMALFIELDSDIPIPPO2007THETERM“SINGLEFLASH”INDICATESTHATGEOTHERMALFLUIDUNDERGOESONEFLASHINGPROCESSINTHESYSTEMFLASHINGISAPROCESSOFLOWERINGTHEGEOFLUIDPRESSUREBELOWTHESATURATIONPRESSURECORRESPONDINGTOTHEFLUIDTEMPERATURETOTRANSFORMPRESSURIZEDLIQUIDTOAMIXTUREOFLIQUIDANDVAPORDIPIPPO2007INORDERTOACHIEVEAFLUIDMIXTUREWITHHIGHERQUALITYANDSTEAMFLOWINTHETURBINEINASINGLEFLASHPOWERPLANT,THEGEOTHERMALFLUIDISSUBJECTEDTOACONSTANTENTHALPYTHROTTLINGPROCESSAFTERTHESEPARATIONOFLIQUIDANDVAPORPHASESINASEPARATOR,THEVAPORISUSEDTODRIVEASTEAMTURBINEANDGENERATEMECHANICALPOWERTHELIQUIDPORTIONOFTHEFLOWISREINJECTEDTOTHESOURCEVIAINJECTIONWELLSDUETOHIGHTEMPERATUREANDRELATIVELYLOWQUALITYINTHESEPARATOR,THEEXITINGBRINEHASAHIGHFLOWRATEANDWORKINGPOTENTIALCOMPAREDTOTHESTEAMUSEDTODRIVETHETURBINEELWAKIL,1985INORDERTOUSETHISWASTEDENERGYINADOUBLEFLASHPOWERPLANT,THELIQUIDEXITINGTHESEPARATORISRUNTHROUGHASECONDFLASHINGPROCESSFLASHVESSELANDSEPARATORTHERESULTINGLOWPRESSURESTEAMISSENTTOALOWERSTAGEOFTHETURBINEORANOTHERSTEAMTURBINEATTHESAMEGEOTHERMALFLUIDCONDITIONS,ADOUBLEFLASHSTEAMPLANTCANPRODUCE1525MOREPOWEROUTPUTTHANASINGLEFLASHSTEAMPLANTHOWEVER,THEPLANTISMORECOMPLEX,MORECOSTLY,ANDREQUIRESMOREMAINTENANCEDIPIPPO2007FLASHSTEAMPOWERPLANTSACCOUNTFORASIGNIFICANTSHAREOFALLGEOTHERMALPOWERPLANTSINTHEWORLDACCORDINGTOTHEAVAILABLEDATAPRESENTEDBYDIPIPPO2007,APPROXIMATELY32OFGEOTHERMALPLANTSINTHEWORLDHAVEASINGLEFLASHDESIGN,ANDAPPROXIMATELY14HAVEADOUBLEFLASHDESIGNINASINGLEFLASHPOWERPLANT,SEPARATORPRESSUREHASASIGNIFICANTEFFECTONTHEAMOUNTOFPOWERGENERATEDFROMEXTRACTEDGEOTHERMALFLUIDANDTHEPERFORMANCEOFTHECYCLEFORSPECIFICFLUIDCONDITIONSATTHEWELLHEAD,HIGHERSEPARATORPRESSURESRESULTINGFROMHIGHERFLASHINGPRESSURERESULTINHIGHERPRESSURESTEAMLEAVINGTHESEPARATORTHEREFORE,STEAMATTHETURBINEINLETWOULDHAVEHIGHERWORKINGPOTENTIALHOWEVER,BYREDUCINGTHEFLASHINGPRESSUREANDTHEDEPENDENTSEPARATORPRESSUREINCREASESTHEMIXTUREQUALITYINTHESEPARATOR,WHICHRESULTSINHIGHERSTEAMFLOWRATESATTHETURBINEINLETHOWEVER,THESPECIFICAVAILABLEENERGYEXERGYOFTHESTEAMFLOWWOULDDECLINETHUS,SEPARATORPRESSUREISAKEYDESIGNPARAMETERINSINGLEFLASHPOWERPLANTSANDHASAMAJORINFLUENCEONPOWERGENERATIONSYSTEMPERFORMANCEINDOUBLEFLASHPOWERPLANTS,THEFLASHINGPRESSURESHOULDALSOBECONSIDEREDASANIMPORTANTDESIGNPARAMETERFOREVALUATIONOFFLASHSTEAMPOWERPLANTS,DESIGNPARAMETERSSHOULDBESELECTEDPRECISELYTOACHIEVETHEMAXIMUMPOWERGENERATIONATTHELOWESTGENERATIONCOSTTHEAIMOFTHEPRESENTWORKISTOINTRODUCEATHERMOECONOMICMODELFORGEOTHERMALFLASHSTEAMPOWERPLANTSOPTIMIZATIONOFDESIGNPARAMETERSFORSINGLEANDDOUBLEFLASHPOWERPLANTSBASEDONTHISMODELMAKESITPOSSIBLETOCOMPAREUTILIZATIONOFTHESEPLANTSINSIMILARCONDITIONSTOACHIEVETHISGOAL,NETPOWEROUTPUTFROMFLASHSTEAMPOWERPLANTSWASCALCULATEDATDIFFERENTGEOFLUIDTEMPERATURESBYUSINGTHERMODYNAMICEQUILIBRIUMSANDCYCLESPECIFICATIONSAFTERCONSIDERINGECONOMICFACTORS,THETHERMOECONOMICOBJECTIVEFUNCTIONWASDEFINEDASTHEGENERATIONCOST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下載積分: 10 賞幣
上傳時間:2024-03-14
頁數(shù): 8
大小: 0.45(MB)
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簡介:APDAPD偏壓電路的最佳設(shè)計偏壓電路的最佳設(shè)計孫純生,秦世橋,王興書,朱冬華孫純生,秦世橋,王興書,朱冬華1國防科技大學光電科學與技術(shù)學院,中國長沙4100732海軍工程大學裝備工程部,中國武漢430033本文提出了一種基于溫度補償和負載電阻補償?shù)难┍拦怆姸O管(APD)反向偏壓控制方法,并詳細的分析了背景光和負載電阻對雪崩光電二極管檢測電路的影響。為雪崩光電二極管偏置電路的設(shè)計建立了一種理想的溫度補償和負載電阻補償模型。據(jù)預(yù)測,這種控制方法特別適用于車輛使用的激光測距儀。實驗結(jié)果證實,本文提出的設(shè)計可以很大程度的改善測距儀的性能。雪崩光電二極管(APD)的特點是具有很高的量子效率和教大的內(nèi)部增益,這可以很大程度的降低對前置放大電路性能的要求,并能提高檢測電路的信噪比SNR。因此,它具有很廣泛的用途,如光纖通信、激光測距儀、微弱信號探測器等。為了使檢測電路能獲得最佳檢測性能,APD的外部電壓需要接近最佳倍增因子時的電壓。由于最佳倍增因子是許多因數(shù)的復函數(shù),如外部溫度、背景光通量、放大器噪聲和系統(tǒng)帶寬,因此需要設(shè)計一個復雜的反饋控制電路及時的調(diào)整雪崩光電二極管的偏壓。當然這就增加了開銷。本文介紹了一種簡單的、避免高開銷的方式,就是確保溫度補償?shù)耐瑫r給APD偏置電路選擇一個合適的負載電阻。通過這種方式,背景光對雪崩光電二極管檢測電路造成的不良影響可在一定程度上得到補償,并且檢測電路抗背景光能力得到了改善。在這種方法基礎(chǔ)上為汽車防撞設(shè)計的激光測距儀能很好地滿足系統(tǒng)的要求。APD激光檢測電路的主要噪聲源包括檢測器噪聲、負載電阻噪聲、放大電路前端噪溫度和背景光條件下電路仍能保持最佳的APD倍增因子。目前有幾種偏置電路控制方法恒流偏置,溫度補償和恒虛報警控制。恒流偏置是只適用于不變的背景光或無背景光情況。溫度補償抗背景光的能力較差。恒虛假控制可以保持最佳的倍增因子,但復雜的電路和高成本才換來較高的性能。本文提出了一種新方法,為APD偏壓電路設(shè)計了溫度補償以及串行電阻背景光補償,實現(xiàn)高性能的同時保持低成本。溫度變化對APD偏置電路的影響主要在兩個方面一是溫度變化使負載電阻噪聲發(fā)生變化,因而改變了APD檢測電路的最佳增殖因子;另一方面,溫度變化改變了APD載流子和晶格之間的碰撞頻率和強度,這也改變了APD的倍增因子。以下就是分析這兩個因數(shù)的影響。APD倍增因子M和其反向偏置電壓V之間的關(guān)系可以用下式描述(3)其中V是APD的反向偏置電壓,是某一確定溫度時的擊穿電壓,N介于1和3之BV間,它由半導電材料、半導體摻雜分配和輻射源的波長決定。在方程3中,當M達到最佳值時反向偏置電壓達到最佳。從方程2和3我們能夠得到最優(yōu)偏置電壓OPTMOPTVOPTV、工作溫度和接收到的背景光功率之間的關(guān)系如下BP(4)方程4只包括APD偏置電路的溫度對負載電阻噪聲的影響,例如上文提到過的一個方面。溫度變化對APD倍增因子影響可表示為溫度系數(shù)。以最佳工作電壓為22TC22V℃作為參考點,溫度變化引起的最佳偏置電壓的變化可以描述為(5)1NBVMV???300411NNNOPTBOPTBSBDBIKTFVVMVERPRPIKR??????????????????????312220041295NNBTSBDBIKTFVVVVVCTERPRPIKR????????????????????????????
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簡介:0南京郵電大學畢業(yè)設(shè)計論文外文資料翻譯學院經(jīng)濟與管理學院專業(yè)學生姓名班級學號外文出處南郵外文數(shù)據(jù)庫附件1外文資料翻譯譯文;2外文原文指導教師評價1.翻譯內(nèi)容與課題的結(jié)合度□優(yōu)√良□中□差2.翻譯內(nèi)容的準確、流暢□優(yōu)√良□中□差3.專業(yè)詞匯翻譯的準確性□優(yōu)□良√中□差4.翻譯字符數(shù)是否符合規(guī)定要求√符合□不符合總評為良。指導教師簽名洪小娟2012年5月3日2定義定義埃德蒙茲2001所界定的復雜性復雜的是,在給定的語言中這難以制定的整體行為,即使給予了相當完整的信息,其原子組件和它們的相互關(guān)系的模型屬性。112112復雜網(wǎng)絡(luò)復雜網(wǎng)絡(luò)網(wǎng)絡(luò)至少早在18世紀已經(jīng)正式出現(xiàn),歐拉在他試圖解決著名的哥尼斯堡橋問題的圖論研究中首先出現(xiàn)。圖論的概念已被廣泛應(yīng)用,因為在這里有一些手段聯(lián)系著實體集的各個學科。調(diào)查這些網(wǎng)絡(luò)結(jié)構(gòu)的特點導致了一系列基礎(chǔ)的分析現(xiàn)代圖理論的解決措施。社會網(wǎng)絡(luò)分析工具的應(yīng)用可以追溯到20世紀初(斯科特,1991),從那以后,社會網(wǎng)絡(luò)分析的規(guī)則SNA成為了網(wǎng)絡(luò)研究涉及的作用物間個人、組織等開發(fā)的一種度量,針對社會角色和相互作用物的不同方面。我們將在第2節(jié)討論SNA。1212典型的復雜網(wǎng)絡(luò)和特點典型的復雜網(wǎng)絡(luò)和特點我們目前只是簡要概述了一個典型復雜網(wǎng)絡(luò)的特點和其顯著特征。一個詳盡的文獻是有用的,尤其是BARABáSI(2001年)和瓦茨(2003提供了一個全面的網(wǎng)絡(luò)解釋。121121隨機圖理論隨機圖理論其中最早嘗試研究這些所謂“復雜網(wǎng)絡(luò)”的行為追溯到隨機圖理論的開創(chuàng)性的工作,在20世紀50年代開始的保羅鄂爾多斯和阿爾弗雷德萊利的ER模型,基本ER模型需要通過選擇隨機等,由此產(chǎn)生的網(wǎng)絡(luò)是從空間的N條邊連接N個節(jié)點。在隨機圖(足夠大)圖表中每個節(jié)點有相同概率,給定線路的概率P并不小,隨機的直徑通常是小直徑增加對數(shù),作為一個隨機圖的擴展。122122PARETOPARETO分布及自組織臨界性分布及自組織臨界性假設(shè)使用統(tǒng)計方法,在許多情況下,標準偏差和數(shù)據(jù)分布是已知和穩(wěn)定的。在許多情況下,人們發(fā)現(xiàn),仿真結(jié)果生成的數(shù)據(jù)具有肥尾和薄高峰被稱為LEPTOKURTOSIS特點。其中一個復雜網(wǎng)絡(luò)的特點是外觀的冪律分布在很多地方。非正式的,這意味著大多數(shù)網(wǎng)絡(luò)連接節(jié)點相對很少也相對較小反之亦然。所謂的冪律(S)源于對帕累托分布、專業(yè)化的帕累托原理,命名VIFREDO帕累托維基百科,2005。概率密度分布函數(shù)的定義為巴泰勒米(2003)討論了兩個參數(shù)XM和K作為分布參數(shù),如果形狀(峰度)參數(shù)KI(0,2K值≤1,平均是無限的,而對于K≤2。方差是有限的。圖1顯示了的薄峰度,這是分布的特點。我們在這里的目的是影響,而不是討論提出一種分析性能的分布,可以發(fā)現(xiàn)任何標準的文本在隨機分布。這些特點為進一步的研究基礎(chǔ)模型和現(xiàn)象的的處理提供線索。我們在后面將回到這個問題上。另一個問題就是“如果這些系統(tǒng)是模擬系統(tǒng)平衡市場所描述的經(jīng)濟理論,規(guī)范效用最大化代理商將不支持大的分析分布式系統(tǒng)性能,”。這進一步鼓勵了在統(tǒng)計簽名驗證相關(guān)理論。事實上,更高,更薄的頻率分布與相應(yīng)的正態(tài)分布,即
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