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Sound-Based Fragmentation Detection
No full text[[abstract]]機器的狀態監測長期以來被認為是避免突發的最有效的解決方案，信號處理在狀態監測和故障診斷過程中起著重要作用。許多類型的信號可用於機器的狀態監測，如振動，電氣和聲音信號。以適當的方式處理這些信號對於提取與特定類型故障相關的最顯著特徵至關重要。各種信號處理技術可以實現這一目的，捕獲信號的性質是選擇合適技術的重要因素。本研究的主要重點是監控系統使用聲音感測的方式來監控機器手臂破片的頻率。結果顯示，使用聲音感測的方式來監控頻率是可以有效地檢測正常環境與破片掉落頻率之間的差異。關鍵字：機械手臂、聲音、監控。[[abstract]]Theconditionmonitoringofmachineshaslongbeenacceptedasamosteffectivesolutioninavoidingsudden，Signalprocessingplaysasignificantroleinconditionmonitoringandthefaultdiagnosisprocess.Manytypesofsignalscanbeusedintheconditionmonitoringofmachines,suchasvibration,electricalandsoundsignals.Processingthesesignalsinanappropriatewayiscrucialinextractingthemostsalientfeaturesrelatedtospecifictypesoffaults.Avarietyofsignalprocessingtechniquescanfulfilthispurpose,andthenatureofthecapturedsignalisasignificantfactorintheselectionoftheappropriatetechnique.Themainfocusofthisstudyistomonitorthesystemusingthesoundsensingmodetomonitortherobotarmfragmentsofaudio。Theresultsshowusingthesoundsensingmodetomonitoraudioistheabilitytoeffectivelydetectthedifferencebetweenanormalenvironmentandaforeignmatterdropaudio.Keyword：ROBOT、Sound、Monito
The Study of Enthusiasm and Alertness on Entrepreneurial Intentions : Take the Domestic Apparel Trader as Subjects.
No full text[[abstract]]創業熱情與創業警覺性是創業的關鍵因素，創業熱情是創業者不畏失敗的創業精神，創業警覺性則是面對不確定市場的感知能力，兩者都是影響創業者是否具有創業意圖的指標。因此，探討創業者如何發揮創業熱情與創業警覺性去提高創業意圖，是本研究主要探討議題。本研究主要針對創業熱情與創業警覺性，對創業者創業意圖的影響，並以服飾業者為研究對象，研究採用問卷調查法，實際有效份數為186份。在統計方法上，本研究以描述性統計分析、單因子變異數分析以及相關係數分析，檢測服飾業創業者在創業熱情、創業警覺性與創業意圖上的關係。根據本研究結果顯示，擁有高度的創業熱情，以及積極的創業警覺性的創業家，也會正向影響到該創業者的創業意圖。最後，本研究也根據創業熱情、創業警覺性對創業者的創業意圖，針對服飾業創業者做創業建議。[[abstract]]Entrepreneurialpassionandentrepreneurialalertnessarekeyfactorsinentrepreneurship.Entrepreneurialpassionisfearlessnessoffailureofentrepreneurialspirit,entrepreneurialalertnessistofacetheuncertaintyofthemarket'sability,bothareimportantindexesofentrepreneurialintentions.Therefore,toexplorehowentrepreneursdevelopentrepreneurialpassionandentrepreneurialalertnesstoincreaseentrepreneurialintentionsisthemaintopicofthisstudy.Thisstudyfocusesontheeffectofentrepreneurialpassionandentrepreneurialalertnessonentrepreneurialintention.Theapparelindustryistheresearchobject.Thestudyadoptsthequestionnairesurveyandthenumberofeffectivesamplesis186.Inthestatisticalmethod,thispaperanalyzestherelationshipbetweenentrepreneurialpassion,entrepreneurialalertnessandentrepreneurialintentionbydescriptivestatisticalanalysis,singlefactorvarianceanalysis,andcorrelationcoefficientanalysis.Accordingtotheresultsofthisstudy,withahighdegreeofentrepreneurialpassion,aswellasapositiveentrepreneurialalertness,willpositivelyaffecttheentrepreneurialintentions.Finally,thestudyalsobasedontheresults,givingentrepreneurssomebusinessrecommendations
The impact of Indictment or Detention of Accused of chairmen movement on stock price
No full text[[abstract]]本研究探討我國上市上櫃公司之負責人遭刑事起訴、羈押時，該公司所公告之重大訊息，是否影響該公司股票之股價。而研究方法採用事件研究法，討論負責人遭刑事起訴、羈押時股價所呈現之反應（蒐集時間2008/01/01至2017/04/28）。實證研究結果顯示：當負責人遭刑事起訴時，僅在事件日翌日（t=+1），股價將出現顯著之負面效應，惟若負責人遭羈押時，則股價之反應於事件期間中之t=-2至t=+2，均出現顯著之負面效應。[[abstract]]Thispaperstudieswhethertheannouncementsofindictmentsordetentionsofaccusedofchairmenhavetheimpactonstockprice.Usingtheeventstudymethod,thispaperdiscussestheimpactsofindictmentsordetentionsofaccusedofchairmenonstockpricemovementfromJanuary,2008toApril,2017.Thispaperfindsnegativeimpactsonstockpriceonlyonthenexttradingdayofindictmentevents.However,ithasnegativeimpactonstockpricepriortoandaftertwotradingdaysofthedetentioneventsofaccused
Impact of CEO power on Corporate Credit Rating
No full text[[abstract]]本研究為探討CEO權力對企業信用評等之影響，選取台灣上市公司2006年至2015年資料，去除金融控股、保險、銀行等資本結構較為特殊之產業，以10年期間的CEO特性資料，與台灣信用評等指標進行多元迴歸分析。本文設定的CEO權力變數共有五項，分別為結構性權力、所有權權力、專家權力、聲望權力以及薪酬權力，並以台灣信用評等指標，作為衡量企業信評以及模型中的應變數，CEO權力為自變數，探討這些CEO權力對企業信用評等的影響性。研究結果顯示：若CEO特徵愈強烈，例如持有公司股份愈多、曾經歷管理職次數愈多、人脈學識愈廣，則公司會有比較好的信用評等，亦代表公司在這類特徵的CEO經營之下，公司的財務結構及狀況，較其他公司相對良好、安全。[[abstract]]ThisstudyisaimedtoinvestigatetheimpactofCEOpoweroncorporatecreditrating.TheobservationperiodissetduringtheperiodbetweenMarch2006toDecember2015.Thesamplefromfinance,insurance,andbankingindustryareeliminatedbecacsetheyhaveabnormalfinancialstructure.Basesdonamultivariatelinearregressionmodel,theTaiwanCorporateCreditRiskIndex(TCRI)isusedasthedependentvariable.TherearefiveCEOcharacteristicsinexplainingCEOpower,includingstructural,ownership,expertise,reputation,andpayslicepoweraretakenastheproxyofCEOpower.TheempiricalresultsconcludethatthefirmwillobtainabettercreditratingifithasastrongerCEOpower,i.e.,CEOholdsmorestockownership,haingmoremanagementexperience,havingwellconnection,andwithhighereducated,itwillhelpthecompanymoresaferandhavingbetterfinancialstructurethanotherfirms
The Study of Hot Forging Die Design and Process Development for Eye Bolt
No full text[[abstract]]本研究以不銹鋼環首螺栓為研究載具，環首螺栓目前製程方式還是以傳統熱間鍛造製程來生產，因為鍛件體積分佈差異大，製程一般需要進行預成形，可以前擠或鍛粗預形方式來進行設計。前擠預形製程，成形負荷大、材料使用量多；鍛粗預形製程，若下料長徑比過大，則需鍛打多次，使頭部成形，因此開發研究環首螺栓熱間多工位鍛造製程，在預成形上設計前擠預形與拘束鍛粗預形方式，進行探討與製程之開發與實際測試。本研究規劃以?25mm與?11mm棒材下料，藉由不同預成形方式分為兩種製程進行探討。?25mm棒材鍛造製程為前擠預形製程其包含前擠預形、打扁、有毛邊完成鍛、沖孔及切邊；?11mm棒材鍛造製程為拘束式鍛粗預形製程其包含拘束式鍛粗預形、有毛邊完成鍛、沖孔及切邊。藉由金屬成形軟體DEFORM－3D進行熱間鍛造之模擬，探討兩種製程在相同參數下，材料在完成鍛造製程下成形負荷與模具應力與製程設計之差異性。根據模擬結果，進行實體模具之開發與實際測試，建立出較佳之製程參數及數據。結果顯示，本研究兩種製程規劃經實際熱間鍛造鍛打，成形狀況與模擬相符。鍛件特徵可完全成形，表面無缺陷。在完成鍛毛邊厚度設計為2mm下，前擠預形製程模擬負荷為134ton，成形負荷為154ton，拘束式鍛粗預形製程模擬負荷為92.9ton，成形負荷為94ton。相較之下，拘束式鍛粗預形製程可以節省約7%材料。在鍛粗時藉由模具設計，可將長俓比5.45:1之材料一次成形，因此工位數較少，進而縮短製造時間、增加材料使用率、降低成本。本研究顯示拘束式鍛粗預形製程為環首螺栓較佳之鍛造製程。[[abstract]]本研究以不銹鋼環首螺栓為研究載具，環首螺栓目前製程方式還是以傳統熱間鍛造製程來生產，因為鍛件體積分佈差異大，製程一般需要進行預成形，可以前擠或鍛粗預形方式來進行設計。前擠預形製程，成形負荷大、材料使用量多；鍛粗預形製程，若下料長徑比過大，則需鍛打多次，使頭部成形，因此開發研究環首螺栓熱間多工位鍛造製程，在預成形上設計前擠預形與拘束鍛粗預形方式，進行探討與製程之開發與實際測試。本研究規劃以?25mm與?11mm棒材下料，藉由不同預成形方式分為兩種製程進行探討。?25mm棒材鍛造製程為前擠預形製程其包含前擠預形、打扁、有毛邊完成鍛、沖孔及切邊；?11mm棒材鍛造製程為拘束式鍛粗預形製程其包含拘束式鍛粗預形、有毛邊完成鍛、沖孔及切邊。藉由金屬成形軟體DEFORM－3D進行熱間鍛造之模擬，探討兩種製程在相同參數下，材料在完成鍛造製程下成形負荷與模具應力與製程設計之差異性。根據模擬結果，進行實體模具之開發與實際測試，建立出較佳之製程參數及數據。結果顯示，本研究兩種製程規劃經實際熱間鍛造鍛打，成形狀況與模擬相符。鍛件特徵可完全成形，表面無缺陷。在完成鍛毛邊厚度設計為2mm下，前擠預形製程模擬負荷為134ton，成形負荷為154ton，拘束式鍛粗預形製程模擬負荷為92.9ton，成形負荷為94ton。相較之下，拘束式鍛粗預形製程可以節省約7%材料。在鍛粗時藉由模具設計，可將長俓比5.45:1之材料一次成形，因此工位數較少，進而縮短製造時間、增加材料使用率、降低成本。本研究顯示拘束式鍛粗預形製程為環首螺栓較佳之鍛造製程。[[abstract]]Thisstudyistoresearchstainlesssteeleyebolts.Theeyeboltsarecurrentlyproducedinthetraditionalhotforgingprocess,becausethebilletvolumedistributionisdifferent.Theprocessdesigngenerallyneedstobepreformedbyextrudingorupsetting.Theextrudingpreformingprocessneedsalargeformingloadandusesmorematerials.Abouttheupsettingpreformingprocess,ifthematerial'sratiooflengthvsdiameteristoolarge,itneedstoforgeseveraltimestoheadforming,Therefore,wedeveloptheeyebolthotmulti-stationforgingprocess.Inthepreforming,thedesignoftheextrudingpreformingandbindingupsettingpreformingtoproceedthisprocess'sdevelopmentandactualtest.Thisstudyisplanningtousediameter?25mmand?11mmbarmaterial,bydifferentpreformingmethodisdividedintotwokindsofprocess,the?25mmbarmanufacturingprocessisextrudingpreformingprocess,whichisincludingextrudingpreforming,flattening,burrstocompleteforging,punchingandtrimming;?11mmbarmanufacturingprocessisbindingupsettingpreformingprocess,whichisincludingbindingupsettingpreforming,burrstocompleteforging,punchingandtrimming.ByusingthemetalformingsimulationsoftwareDEFORM-3Dtosimulateforhotforging.Thentoexploretwoprocessesarebasedonsameparameters,thedifferencebetweeninhotforgingtheformingloadandthediestressandtheprocessdesignwhenthematerialisunderthesameparameters.Accordingtothesimulationresults,thephysicalmolddevelopmentandactualtest,toestablishabetterprocessparametersanddata.Theresultsshowthatthetwomanufacturingprocessesofthisstudyarecarriedoutbytheactualhotforging,andtheformingsituationisinaccordancewiththesimulation.Billetiscompletelyformed,thesurfaceiswithoutdefects.Theburrsthicknessisdesignedfor2mmincompletedforging,theextrudingpreformingprocesssimulatedformingloadis134ton,theformingloadis154ton.Thebindingupsettingpreformingprocesssimulatedloadis92.9tonandtheformingloadis94ton.Incontrast,thebindingupsettingpreformingprocesscansaveabout7%ofthematerial.Inupsettingbythemolddesign,thematerial'sratiooflengthvsdiameterbythe5.45:1canbeformedonce,Sothelessnumberofstationscanreducemanufacturingtime,increasematerialusageandreducecosts.Thisstudyshowsthatthebindingupsettingpreformingprocessisapreferredforgingprocessfortheeyebolts.[[abstract]]Thisstudyistoresearchstainlesssteeleyebolts.Theeyeboltsarecurrentlyproducedinthetraditionalhotforgingprocess,becausethebilletvolumedistributionisdifferent.Theprocessdesigngenerallyneedstobepreformedbyextrudingorupsetting.Theextrudingpreformingprocessneedsalargeformingloadandusesmorematerials.Abouttheupsettingpreformingprocess,ifthematerial'sratiooflengthvsdiameteristoolarge,itneedstoforgeseveraltimestoheadforming,Therefore,wedeveloptheeyebolthotmulti-stationforgingprocess.Inthepreforming,thedesignoftheextrudingpreformingandbindingupsettingpreformingtoproceedthisprocess'sdevelopmentandactualtest.Thisstudyisplanningtousediameter?25mmand?11mmbarmaterial,bydifferentpreformingmethodisdividedintotwokindsofprocess,the?25mmbarmanufacturingprocessisextrudingpreformingprocess,whichisincludingextrudingpreforming,flattening,burrstocompleteforging,punchingandtrimming;?11mmbarmanufacturingprocessisbindingupsettingpreformingprocess,whichisincludingbindingupsettingpreforming,burrstocompleteforging,punchingandtrimming.ByusingthemetalformingsimulationsoftwareDEFORM-3Dtosimulateforhotforging.Thentoexploretwoprocessesarebasedonsameparameters,thedifferencebetweeninhotforgingtheformingloadandthediestressandtheprocessdesignwhenthematerialisunderthesameparameters.Accordingtothesimulationresults,thephysicalmolddevelopmentandactualtest,toestablishabetterprocessparametersanddata.Theresultsshowthatthetwomanufacturingprocessesofthisstudyarecarriedoutbytheactualhotforging,andtheformingsituationisinaccordancewiththesimulation.Billetiscompletelyformed,thesurfaceiswithoutdefects.Theburrsthicknessisdesignedfor2mmincompletedforging,theextrudingpreformingprocesssimulatedformingloadis134ton,theformingloadis154ton.Thebindingupsettingpreformingprocesssimulatedloadis92.9tonandtheformingloadis94ton.Incontrast,thebindingupsettingpreformingprocesscansaveabout7%ofthematerial.Inupsettingbythemolddesign,thematerial'sratiooflengthvsdiameterbythe5.45:1canbeformedonce,Sothelessnumberofstationscanreducemanufacturingtime,increasematerialusageandreducecosts.Thisstudyshowsthatthebindingupsettingpreformingprocessisapreferredforgingprocessfortheeyebolts
Study on the On-Line Monitoring of Punch Failure in Piercing Process
No full text[[abstract]]在沖孔製程中，當沖頭磨耗嚴重時，會影響產品品質，此外，沖頭斷裂時，會影響產品合格率。因此，沖孔製程沖頭失效的即時監控也就變得相當重要，然而，世界現有的沖壓製程監控卻相當稀少。本研究的目的是探討沖孔製程中，沖頭損壞的及時監控。本研究藉由在精密沖床裝設負荷計、麥克風與加速規，量測沖頭在精微沖孔生命週期的負載、噪音與振動訊號，並與對應期間沖頭磨耗及板材毛邊建立關聯，作為沖孔製程以感測器線上及時監測沖頭損壞的依據。本研究實驗是以沖頭直徑0.8mm微沖孔加工為例，板材材質為不鏽鋼SUS304，板材厚度0.5mm，沖壓機速度為50rpm。實驗結果顯示，沖頭斷裂前，上模振動訊號在頻率280Hz~500Hz間的峰值明顯變大，下模振動訊號則是在頻率400Hz~750Hz間的峰值有明顯變大，噪音訊號在頻率300Hz~450Hz間的峰值也有變大。在沖切過程，隨著沖切次數增加，沖頭刀刃磨耗逐漸增大，板材毛邊增高，沖切力亦會增加。此外，重現性實驗結果可知，兩次沖頭斷裂時的沖切次數誤差在10%以內。[[abstract]]Inthepiercingprocess,whenthewearofpunchbecomesserious,willaffectthequalityoftheproduct.Inaddition,thebrokenpunchwillaffecttheproductpercentofthepass.Asaresult,theimmediatemonitoringofthepunchfailureinthepiercingprocessbecomesmoreimportant.However,theexistingmonitoringofpunchingprocessisratherscarceintheworld.Thepurposeofthisstudyistoinvestigatetheimmediatemonitoringofpunchdamageinthecuttingprocess.Inthispaper,theload,noise,andvibrationsignalsaremeasuredinthemicroprecisionpunchinglifecyclebytheloadmeter,themicrophoneandacceleratinggagethasetupintheprecisionpunchingmachine.Andassociatedwiththepunchwearandtheburoftheboardduringthecorrespondingperiod.Thepiercingprocessisbasedonthesensortoon-linemonitorthedamageofthepunchintime.Thisstudyisbasedonmicro-punchingprocessingusedthepunchdiameterof0.8mm,theplatematerialforthestainlesssteel(SUS304),sheetthicknessis0.5mm,punchingmachinespeedof50rpm.Theexperimentalresultsshow,beforepunchbroken,thepeakvibrationsignalbetweenthefrequencyof280Hz~500Hzobviouslyincreasedwhenthepunchnearlybroken,thelowermodevibrationsignalisobviouslylargerinthefrequencybetween400Hz~750Hz,thenoisesignalisatthefrequencyof300Hz~450Hzbetweenthepeakalsoincreased.Inthecuttingprocess,withthenumberofpunchingincreased,thewearofcuttingedgeofpunchisgraduallyincreased,burofthesheetisincreased,punchingforcewillincrease.Inaddition,thereproducibilitytestresultsshowthatwhenthepunchbroke,thepunchingtimesofthetwopunchesarelessthan10%
A Watermarking Scheme for Tamper Detection and Recovery of Color Images by Using Arnold's Cat Map and Multilevel Thresholding
No full text[[abstract]]紙本論文延後公開至2022年08月17日止[[abstract]]紙本論文延後公開至2022年08月18日
On-line Tuning Parameters of PID Controller with PSO Approach for Remote Haptics Manipulators
No full text[[abstract]]紙本論文延後公開至2022年08月16日止[[abstract]]紙本論文延後公開至2022年08月16日
Study on tuning the emission color of light emitting diode based on cholesteric liquid crystals
No full text[[abstract]]紙本論文延後公開至2018年08月30日止[[abstract]]紙本論文延後公開至2018年08月30日
A Study on the Fabrication of Chemical Vapor Deposited Graphene from Ethanol Carbon Source
No full text[[abstract]]紙本論文延後公開至2022年08月31日止[[abstract]]紙本論文延後公開至2022年08月31日