Simulation Model of Container Land Terminals

Transcription

1 th Intrnational Journal on Marin Navigation and Safty of Sa Transportation Volum 12 Numbr 2 Jun 218 DOI: / Simulation Modl of Containr Land Trminals A.L. Kuzntsov, A.V. Kirichno & J.J. Eglit Admiral Maarov Stat Univrsity of Maritim and Innr Shipping, St. Ptrsburg, Russia ABSTRACT: Th simulation as a tool for th dsign of port and trminals has mrgd as an answr for th dmand to nhanc th quality and rliability of th projct rsults. Vry high costs of th projct solution implmntation and practically total lac of liquidity of transport infrastructur objcts always inducd th immns commrcial riss in th trminal businss. Latly ths riss hav multiplid significantly du to rapid changs on th global and rgional marts of transport srvics. Today, many prts com to s this volatility as an indicator of th nt phas in dvlopmnt of th global trad systm and th drivativ cargo transportation systm, spcifically th stat of tmporal saturation. Th shift of th global goods volums from quic and stady growth to rlativly small fluctuations around constant valus causs quic oscillations in rdistribution of dmand ovr th ovrsizd supply. This nw businss and conomic nvironmnt sriously affctd th paradigm of transport trminal dsign and dvlopmnt tchniqus. Th nw oprational nvironmnt of trminals put a rqust for th dsignrs to arrang th rsults not in trms of point, but in trms of functions. Evntually it rsultd in dvlopmnt of th modrn objct orintd modl approach. Th wid sprad of this approach witnsss th objctiv dmand for this disciplin, whil in many aspcts it rmains in th intuitiv (pr paradigmal) phas of its dvlopmnt. Th main rason for it is in th problm dfinition itslf, which usually is formulatd as th simulation of a givn trminal. At th sam tim, th tas is to assss th oprational charactristics of th trminal ngagd in procssing of a givn combination of cargo flows. Consquntly, it is not th trminal that should b simulatd, but th procsss of cargo flows handling prformd by this trminal undr invstigation. Anothr problm that rstricts th practical sprad of simulation is in th modl adquacy. A modl which adquacy is not provd has no gnosological valu at all. Th papr dscribs th approach aimd at dvlopmnt of th modls with th faturs discussd abov. 1 INTRODUCTION Th analytical tchniqus for th assssmnt of lmnts paramtrs to big systms with compl functional connctions [1 2]. Th dmands for gtting mor adquat and accurat stimations of charactristics, translatd into slctd critria of th quality of th oprations, fac th stochastic natur both of th valus and th mchanisms of thir intractions. Th ncssity to dal with th stochastic valus of all rfrncd and rsulting paramtrs, along with thir innr transformations, push th practic of th trminal dsign towards th simulation approach. Corrct us of th simulation nabls to study th objct s bhavior (rgardd as th valuation of th paramtr valus ovr tim), which is th rsult of th constituting lmnts intractions through idntifid tis btwn thm. A dtrminat algorithm of this 321

2 procss givs way to an uncontrolld chanc intractions of th objcts in th bullion of softwar nvironmnt slctd for th implmntation of th modl. Th rsult is th rsolving bhavior of th systm s rspons to th rfrnc inputs and intrfring trnal influncs, studid undr diffrnt st of th systm stat paramtrs. Th statistic procssing of th rcivd data nabls to obtain th intgral distribution curvs fully dscribing th paramtrs as stochastic valus. Th dynamics obsrvd in th cours of th simulation primnts nabls to ma th judgmnts ovr th rliability of th stimations. Modrn containr trminals, spcifically dry ports with tndd functionality and complity, by all mans blong to th catgory of objcts, whos bhavior cannot b assssd analytically. This problm is studid by many rsarchrs [3 5], rporting important and usful partial rsults. At th sam tim, most oftn th objctivs of ths studis ar dclard as th simulation of th trminals, whil th main goal is to simulat th cargo flows on thir ways trough th trminals. For sa containr trminals ths cargo flows and thir functional trajctoris ar rlativly standard, whil th wid spctr of functional profils of dry ports and land distribution cntrs causs th wid varity of th corrspondnt cargo flow structurs. In addition, th collction of statistics, input rfrncs, primnt planning and intrprtation of rsults mt th lac of th unanimity in th trminology concrning primal cargo flows and thir handling on thir routs through th trminal. This study idntifis all possibl cargo flow classs, which dmand diffrnt tchnological rsourcs in diffrnt quantitis for thir handling. For simulation of ths flows handling, a gnralizd univrsal modl of dry port typ containr trminal is introducd. Th structural lmnts of this modl forms a unifid format for th formal dscription of tchnological routs that diffrnt classs of cargo follow on thir way through th trminal. Splitting of all tchnological oprations into indivisibl primal movs provids th possibility of an qually formal dscription of th trminal handling systm in trms of th quipmnt usd for ths oprations. Th simplicity of this dscription significantly rducs th laboriousnss of th simulation primnts, which in its turn nabls to ta tnsiv studis of th wid varity of cargo handling systms and larg sts of possibl cargo flows. Evntually, th discussion of th rsults provids univrsal mthods of paramtr stimations and rcommndations on utilization of th objct orintd simulation as a tool for tchnological dsign of containr trminals. miing with mpty containrs. Strippd from containrs, th bra bul mas th trminal its gnrating point, simultanously turning ladn bos into mptis. Th containr stuffing rvrts ths procsss. At th sam tim, both ladn and mpty containrs ar not calculatd in tons, as wll as th bra bul is not calculatd in tus. Containrs could b countd both in tus and in physical bos. This ambiguousnss of trminology and intrprtation usd for dnoting th most obvious and principally important trminal oprations bcoms a significant problm not only in planning of national and rgional transport systms, analyss of port and trminal fficincy, but also in thir tchnological dsign [6]. Th cargo flows in dry ports by dirction could b dividd into inbound (crossing th trminal boundary inwards in any plac) and outbound (crossing it outwards). This is a principal distinguishing fatur btwn dry and sa ports, sinc in th lattr th flows ar classifid by th dirction of crossing th brth lin (import and port). By th typ of cargo, both inbound and outbound flows could b dividd into bra bul and containr flows. By th man of procssing at th trminal, th bra bul and containr flows could b dividd into straight and convrsing ons. Th straight flows assum only transportation of cargo through trminal and do not imply th transformation of bra bul into containr and othrwis. Th convrsing flows ar rprsntd by two typs: inbound flow of bra bul which is transfrrd into outbound containr flow (th stuffing flow), and inbound containr flow which is transfrrd into outbound bra bul flow (th stripping flow). Loading of bra bul into containrs dmands for th flow of mpty containrs for stuffing. Th stripping of ladn containrs gnrats anothr flow of mpty (unloadd) containrs. Ths to innr trminal flows ar calld concomitant. Th volums of gnratd and consumd mpty containrs could diffr, thus dmanding th dlivry from outsid in cas of th dficit and dispatch from th trminal in cas of th surplus. In addition to th compnsation of this diffrnc, a trminal could prform th function of rpositioning of th mptis btwn stuffing and stripping sits in th hintrland. Anyway, in addition to straight (non convrsd) flows of bra bul and containr, thr appars a sparat flow of th mpty containrs. With all ths considrations taing into account, th gnralizd schm of cargo flows passing th dry port is introducd in Fig METHODS AND MATERIALS 2.1 Static simulation Containrizd cargo displays crtain uniqu faturs unnown in convntional transportation. Bra bul could arriv in port loadd in containrs, bing rgistrd not in tons, but in tus or bos, thus Figur 1. Gnral schm of cargo flows. 322

3 Th functional structur of th dry port consists of spac localizd procssing cntrs (lmnts), whos connctions corrspond to diffrnt trminal cargohandling oprations, as Fig. 2 shows. Figur 2. Functional structur and cargo catgoris. In othr words, th cargo flows shown by Fig. 1 actually pass ovr th trminal systm s lmnts displayd on Fig. 2. Consquntly, vry cargo flow from Fig.1 could b dscribd by th squnc of functional lmnts it passs on its tchnological rout ovr th trminal, i.. 1, 2,, I. In its turn,ach pair of adjacnt lmnts from this list i, j dfins on tchnological opration l=(i,j) of cargo handling, dnotd by arrows on Fig. 2. As a rsult, nowing th valu of a partial cargo flow Q ovr a crtain tim intrval mas it possibl to dfin its tchnological laboriousnss Q; 1 1, 2,, I, as wll as to assss th rquird opration volum l=(i,j) for any cargo flow, or Q : i, j. Th nowldg of th total cargo flow structur and volum Q; 1, 2,, I, 1, K nabls to ma a prcption of th rquird opration K volums l=(i,j) for th slctd tim priod, l or Q Q; i, j. 1 In its turn, vry tchnological opration shown on Fig. 2 could b split into indivisibl ʹatom movs [7], prformd by on or svral spcis of cargo handling quipmnt classs (Fig. 3). Evry opration assums its own consqunc of th quipmnt spcis t l 1, t l 2,, t l L, also shown on Fig. l 3. Th rfrncd volum of vry opration Q nabls to assss th rquirmnts for th quipmnt l l l l involvd in this opration Q ; t1, t2,, t L. Summing togthr th dmands for all groups of quipmnt, it is possibl to gain th stimation for th rquird flt. Th sam way th rlvant tchnological rsourcs could b assssd: manning, ful consumption, lctricity, aras, rpair and maintnanc facilitis tc. At th sam tim, th actions discussd abov dscrib so calld static modl, using for th prliminary stimations of th tchnological rsourcs ovr rathr long priods,.g. a sason or a yar. All partial cargo flows, rprsntd by thir volums and tchnological routs, hav on qually important charactristin: th distribution ovr tim intrval. Evry flow could b vnly sprad ovr a priod, condns in a part of it, ovrlap with othr or fall into mpty fragmnts. Morovr, th tchnological rsourcs for partial cargo flows ar rstrictd, which causs th comptition of th flows for th rsourcs. In its turn, it lads to tnsion of th cargo flow procssing, dlays and quus. This particular mchanism is rsponsibl for th stochastic fluctuations of th trminal opration paramtrs, which ruls out th analytical mthods of trminal dsign. Figur 3. Opration dscription in trms of primal movs 323

4 Вход ЖД очередь на 35входе ЖД Выход ЖГФ Вход АМ очередь на входе АМ Выход АМ Вход оп Очередь на входе оп Вход оп Очередь на входе оп Выход оп Выход оп Вход оп вход оп Очередь на входе оп Очередь на входе оп Выход оп Выход оп Figur 4. Th scrnshot of th simulation monitoring In ordr to ma judgmnts ovr th trminal paramtrs intrprtd as stochastic valus, th dynamic or th objct orintd simulation approach is usd. 2.2 Dynamic simulation Th dynamic simulation utilizs th sam functional modl shown on Fig. 2. Th principal distinguishing fatur is that this modl is usd for prmannt rcalculation of all valus dscribing th stat of th systm on vry stp of th simulation procss. This stat dpnds on th input rfrnc at this momnt and th stat of th systm at prvious momnts. This statmnt mas clar that th dscribd paradigm hr is so calld discrt vnt simulation [8]. In ordr to plain this approach lt us considr an ampl of two cargo flows, whos routs through th trminal ar dscribd by th schmata , 2, 5, 7, 6 and , 6, 5, 2, 1. For crtainty, lt us assum that 1 is th rail cargo front, 2 is th prstacing ara for rail oprations, 5 is th containr yard, 6 is th documnt offic and 7 is th truc gat to th trminal. Th rfrncd inputs to th modl ar th train arrivals (flow 1) and truc arrivals (flow 2) to th trminal, gnratd by various probability q pattrns. Th party siz of th arriving cargo is also a stocahstic valu gnratd by a slctd distribution. Evry vnt undr th slctd notation ar ordrd lists q ; 1, 2, 5, 7, 6 and q ; 7, 6, 5, 2, 1. An ampl of this gnration is givn by Tab. 1. At any stp of th simulation, th arrival vnts put th corrspondnt amount of cargo as a job in th quu for handling by an lmnt. If thr is a comptitiv oprational rsourc allocatd for this lmnt at this momnt, it collcts th corrspondnt amount of cargo for handling. Th jobs procssd by th lmnt as th srvr ar dirctd to th nt lmnt in lin dfind by th typ of th cargo flow, i.. by th squncs q ; 1, 2, 5, 7, 6 and q ; 7, 6, 5, 2, 1, constituting th modl logics. Tabl 1. Th sampl of input flows gnration Tim Input 1 Input All ths oprations in th modl ralization ar prformd by th standard componnts quus, srvrs, switchs tc. Th distribution of th l l l quipmnt pool rcourss t1, t2,, t L by oprations is dirctd by th stablishd priory of th flows and factual dmands for thm, dfind by th simulation procdur itslf. Th stat of vry componnt of th modl rflcts th cours of opration prformanc, rlvant dlays and quus (Fig. 4). Fig. 5 as an ampl shows dtaild graphics of th jobs waiting in th quu for transportation from th pr stacing ara to th containr yard. 324

5 Figur 5. An ampl of th paramtr s dynamics rcord Fig. 6 displays th histograms of this paramtr s valus distributions in th simulation primnts with diffrnt prioritis of th rsourcs allocation. 3 RESULTS Th mchanisms for simulation of th intracting cargo flows shown in th prvious sction with th hlp of a simplifid ampl ar implmntd on th spcial objct orintd softwar platform. Th intraction of th cargo flows practically mans thir comptition for diffrnt tchnologic rsourcs of th trminal: cargo fronts, warhous facilitis, functional aras, handling quipmnt, prsonal tc. For th sam cargo flows, th sizs of spcific rsourcs and th algorithms of thir allocation undr dficit ld to diffrnt valus of th trminal paramtrs, rsponsibl for th quality of th rndrd commrcial srvics. By th changing of tchnological paramtrs, rsponsibl for quantitativ and qualitativ charactristics of th trminal, it is possibl to rach th dsird lvl of th srvic quality, commonly masurd by th lngth of th quus, waiting and srvicing tim. On th othr hand, th ownr of th trminal using simulation could build th prcption of th financial input rquird to maintain th quality of srvicing. In this way, th simulation provs out itslf to b an fficint tool to support not only tchnological, but ntrprnur dcisions. 4 DISCUSSION Figur 6. Quu lngth with diffrnt proprity assignmnt (flow 1 : flow 2) a) 25:75 b) 5:5 c) 75:2 Th modrn highly comptitiv transport businss nvironmnt, with gnral dtrioration of profitability and growth of cargo flows volatility, mas th intuitiv approachs for taing capital intnsiv ntrprnur dcisions, basd upon ovrsimplifid analytical mthods, a srious thrat for th trminal businss. Th mthodic of th simulation, promising today so much for th businss, in many cass coms to ralization of a rprsntativ ampl, to a crtain tnt rflcting a possibl variant of a crtain dmonstrativ cargo flow. Th quality of th modl oftn is judgd not by th siz of rprsntativ st, or accuracy and rliability of th rsults, but by th quality of th graphic animation of th modl. Actually, this charactristic is on of th lss important from gnosological point of viw. Th simulation modl whos adquacy is not provd has trifling pragmatic valu as a tool of dsign and dcision support. This postulat is th y ston for th whol approach dscribd in this papr and implmntd in th practically important softwar toolit. Th most important componnt of any dsign projct basd on 325

6 this mthodic is a strict, consistnt and cohrnt proving of th modl s adquacy to th primal objct, for what th spcially dsignd instrumnts and mthods ar usd. Only aftr a vry carful validation, thorough calibration and sufficint vrification th modl could b usd as a woring tool. Th utilization of th carfully adjustd mchanisms of th objct orintd simulation, rachd in th cours of th adquacy proving procdur and in th procss of rationally plannd movmnt to th clarly statd goal mt vry pctation in svral larg infrastructural projcts daling with dry port containr trminals. Th princ gaind during this study nabld to adjust th prformanc of this dsign mchanism and rctify th mthodic of its application. 5 CONCLUSIONS 1 Traditional approachs dclar th trminal simulation as thir goal, whil it is ncssary to simulat th cargo flows passing through th trminal functional systm. 2 Sa and dry containr trminal diffr cardinally by th structur, contnt and functional dsignation of thir lmnts, which rquirs to dvlop diffrnt modl for thm. 3 A gnralizd univrsal modl structur is introducd, orintd on a wid class of containr trminal of th dry port and distribution cntr typs. 4 A univrsal format for dscription of typical cargo flows passing th trminal along diffrnt tchnological routs and utilizing its functional lmnts in diffrnt way is suggstd. 5 A univrsal format for functional oprations dscription in trms of th ngagd tchnological quipmnt is introducd. 6 Ths univrsal mans of th cargo flows and dscription of th rquird transport and tchnological quipmnt nabl to study various cargo handling systms undr diffrnt scnarios asy and fficintly. 7 Sinc any simulation is only an instrumnt of analyss, th procdur of synthsis should b constructd as a dirctd changing of tchnical paramtrs, with simulation as a tool for th comparativ study of thir valus. 8 This controlld sarch in th rang of possibl solutions tas a form of typical scnario gnration, undr which th simulation primnts ar plannd and prformd to provid th statistical rliability. 9 Th dscribd tchniqus ar implmntd in th form of ddicatd softwar with practical rcommndations on thir us. 1 Th simulation approach for th tchnological dsign discussd in th papr has provd its worthinss by utilization in svral big transport infrastructur projcts. REFERENCES Alnadr L. Kuzntsov. Gnzis agntnogo imitazionnogo modlirovania v hod razvitia mtodov tchnologichsogo protirovania portov I trminalov / Epluatazia vodnogo transporta. N 4(58) 29, c.3 7 Alnadr L. Kuzntsov. Morsaja ontjnrnaja transportno tchnologichslaya systma/ St.Ptrsbur: MANEB print. hous, с. Nvins, M. R., C. M. Macal, R. Lov, and M. J. Brogn Simulation, animation and visualization of saport oprations. SIMULATION 71 (2): Lgato P. A simulation modlling paradigm for th optimal managmnt of logistics in containr trminals. P. Lgato, R. Trunfio // Procdings of th 21st Europan Confrnc on Modlling and Simulation. Pragu, Czch Rpublic. P Najib M. A containr trminal managmnt systm / M. Najib, A. El Fazzii, J. Bouachour // Procdings of th Intrnational Confrnc on Harbour Maritim and Multimodal Logistics M&S, 212. P Alnadr L. Kuzntsov. Evoluzya poazatly haratrisujushih rabotu morsih portov i trminalov // Vstni GUMRF (34). C Alandr Kuzntsov. Classification of modrn containr handling tchnologis / Cargo systms, Jun 29, pp P. Hstr, S. Diallo Towards a Thory of Multimthod M&S Approach: Part I. In Procdings of th 214 Wintr Simulation Confrnc, ditd by A. Tol, S. Diallo, I. Ryzhov, L. Yilmaz, S. Bucly, and J. Millr,