简介:Thispaperstudiesonlineschedulingofjobswithkindreleasetimesonasinglemachine.Here“kindreleasetime”meansthatinonlinesetting,nojobscanbereleasedwhenthemachineisbusy.EachjobJhasakindreleasetimer(J)≥0,aprocessingtimep(J)>0andadeadlined(J)>0.Thegoalistodetermineaschedulewhichmaximizestotalprocessingtime(∑p(J)E(J))ortotalnumber(∑E(J))oftheacceptedjobs.Forthefirstobjectivefunction∑p(J)E(J),wefirstpresentalowerbound√2,andthenprovideanonlinealgorithmLEJwithacompetitiveratioof3.Thisisthefirstdeterministicalgorithmfortheproblemwithaconstantcompetitiveratio.Whenp(J)∈{1,k},k>1isarealnumber,wefirstpresentalowerboundminf(1+k)/k,2k/(1+k)g,andthenweshowthatLEJhasacompetitiveratioof1+┌k┐=k.Inparticular,whenalltheklengthjobshavetightdeadlines,wefirstpresentalowerboundmax{4=(2+k),1}(for∑p(J)E(J))and4/3(for∑E(J)).ThenweprovethatLEJis┌k┐/k-competitivefor∑p(J)E(J)andweprovideanonlinealgorithmHwithacompetitiveratioof2┌k┐/(┌k┐+1)forthesecondobjectivefunction∑E(J).
简介:Background:Athletes,coaches,sportpsychologypractitioners,andresearcherssuggestthatmentaltoughnessrepresentsanimportantconstructthatisassociatedwithathleticperformance.Unfortunately,theabsenceofreal-worldperformanceasadependentvariablehaslimitedourabilitytosubstantiatethisclaim.Theconcernofalackofecologicallyvalidmeasuresofsportsperformancemightbeaddressedbyexaminingtherelationshipbetweenmentaltoughnessandsportsperformanceusingastandardizedmeasureofpersonalbest(PB)triathlontimeandavalidatedunidimensionalmeasureofmentaltoughness.Methods:Threehundredandsixteentriathletescompletedthe8-itemmentaltoughnessindex(MTI),reportedtheirage,andprovidedaPBOlympicdistancetriathlontimeandthetotalnumberoftriathlonstheyhadcompletedtodate.Giventhatmalesaretypicallyquickerthanfemales,astandardizedtimewascalculatedbydividingthePBbythecurrentOlympicrecordforgender;wealsohypothesizedthatmoreexperiencedtriathleteswouldreportquickerPBtimesbecauseofgreaterfrequencyanddurationoftraining.Oncewehadcontrolledforgenderandexperience,wepredictedthatmentaltoughnesswouldbenegativelyassociatedwithtriathlontimeandthesizeoftherelationshipwouldbeofamoderatemagnitude.Results:Resultsrevealedsmall-tomoderate-sizednegativerelationshipsbetweenbothcompletednumberoftriathlonsandmentaltoughnesswithstandardizedPBtime.Conclusion:ThehierarchicalregressionanalysisshowedthatmentaltoughnessprovidedauniquecontributiontothevariabilityinstandardizedOlympictriathlonPBaftercontrollingforthetotalnumberoftriathlonscompleted.
简介:就是传统儒家那种主张血缘亲情本根至上、坚持血亲情理精神的特殊主义理论架构,而传统儒家的特殊主义血亲情理精神,并且因此根本否定传统儒家主张的血缘亲情本根至上的基本精神
简介:摘要传统节日所承载的文化对于一个民族的精神记忆有着一份独特的价值。中国的传统节日形式多样、内容丰富,是弘扬中华民族优秀传统文化和传承中华传统美德的重要载体。在当今世界多元文化并存、中西方文化交融的环境下,利用好传统节日揭示传统文化的内在价值,弘扬民族精神,加强对小学生的传统文化教育具有十分重要的意义。