ISSN : 0974-7435 Volume 10 Issue 3 Comprehensve evaluaton research of volleyball players athletc ablty based on Fuzzy mathematcal model Shangbn L, Peyu Zhao, Yngshuang Lu, Lxn Wu* Physcal Educaton Department, Harbn Engneerng Unversty, Harbn, 150001, (CHINA) E-mal: wulxn@hrbeu.edu.cn BTAIJ, 10(3), 2014 [621-629] ABSTRACT In the confrontaton process of volleyball, the key to ultmate vctory s athlete s athletc ablty; f we can establsh a comprehensve evaluaton system and model of volleyball players, t helps targeted tranng and sklls mprovement of athletes, and wns more honor for Chnese sports crcle. Ths paper studes the techncal and tactcal characterstcs of volleyball players, starts from the physcal aglty, sklls, psychology and ntellgence four areas n order to establsh a comprehensve evaluaton system of volleyball players and explore the scentfc, reasonable and workable evaluaton methods, and contrbutes to the targeted tranng of athletes. The study gves fuzzy set defnton wth the hundred-mark system and fve evaluaton grades, and provdes algorthm for the quanttatve analyss of each s test results n the system, fnally gves the algorthm steps of volleyball players comprehensve evaluaton based on fuzzy mathematcal model, and provdes a theoretcal bass for the reasonable evaluaton of the athlete. 2014 Trade Scence Inc. - INDIA KEYWORDS Volleyball tactcs; AHP analyss; Judgment matrx; Fuzzy mathematcs; Index quantfcaton. INTRODUCTION After nearly a century of development, the modern volleyball has become one of the projects wdely used n the world, whch s one of the most favorte sports and has the greatest nfluence. Along wth the reform of contemporary volleyball competton system, t makes the sport take the fast change, superb skll and great strength as purposes; t has become the drvng force of the development trend of volleyball, but t does not gnore the mportance of people; the problem here s the ablty of the athlete; only enhancng the comprehensve strength of volleyball players can promote the reform and development of the project more convenently. Ths paper takes volleyball for example, conducts analyss of the athletes physcal ablty, sklls, psychology and ntellgence, explores the core factor that nfluences the athletes athletc ablty, and provdes a bass for the comprehensve evaluaton of athletes. For the research of volleyball players comprehensve evaluaton a lot of people have made efforts; t s these people s efforts that make Chna lead the advanced level of the volleyball world, some people study the evaluaton of athletes from physcal ftness; some people study from the techncal tactcal level, some others study from the physologcal parameters; from whch
622 Comprehensve evaluaton research of volleyball players athletc ablty based BTAIJ, 10(3) 2014 : Yang yang (2013) took three Unverstes n Gansu Provnce for an example to study volleyball players, used lterature, Delph method, mathematcal statstcs and other methods to construct the level system of specal ftness for Gansu college volleyball players, evaluated the volleyball players specalzed physcal ftness, fnally establshed scorng crtera, and provded reasonable suggestons for the upgrade of athletes specal ftness [1] ; Zhang Xao-dan (2013) studed specalzed sports qualty ndcators of the Chnese elte female beach volleyball players based on the lterature and expert questonnare, tested the women s volleyball players that are n actve servce and also the women s volleyball players preparng for the 2008 Olympc, establshed the target structural model of players specfc qualty assessment, and provded a theoretcal bass for the tranng objectves of Chnese women s natonal beach volleyball team [2] ; Guo Yu-je et al (2014) compared the compettve level and dfferences of aerobc, anaerobc capacty for volleyball players at dfferent postons, and explored aerobc, anaerobc capacty characterstcs and laws of excellent women s college volleyball players, provded a theoretcal bass for the athletes functon evaluaton and tranng arrangements before the competton [3]. On the bass of prevous studes, ths paper analyzes the physcal, skll, mental and ntellectual characterstcs of athletes reflected n women s volleyball tournament, extracts the to conduct the comprehensve evaluaton on volleyball players, and establshes a comprehensve evaluaton system; n the late process of the research, t uses the evaluaton method of fuzzy mathematcal model, provdes a theoretcal bass for the comprehensve evaluaton of volleyball players, and provdes gudance drecton for the targeted tranng of athletes. Study object STUDY OBJECT AND METHOD Ths paper takes the20 players n the women s volleyball team as the study object, and the basc stuaton of the players s shown n TABLE 1. TABLE 1: The basc nformaton of the study object Category Number of people Category Number of people Master Sportsmen 9 16~18 years old 7 Frst level athletes 6 18~20 years old 4 Second level athletes 5 20~22 years old 5 14~16 years old 2 22~24 years old 2 Study method Lterature It searches CNKI database and fnds out 30 journal artcles and 9 master s thess on the applcaton of sports tranng theory, volleyball players athletc ablty and fuzzy mathematcs n evaluaton of athletes, provdes a theoretcal bass for the comprehensve evaluaton of volleyball players n ths artcle, and provdes the bass for the ndcators extracton n athletes evaluaton system. Expert ntervewng method In order to screen the ndcators, conduct authortatve survey of the establshed system; n order to provde advce for the exstng problems and urgent problems n the teachng, t needs the ntervews of expert; consderng the authorty of the establshed tactcal teachng system, ths paper sets up the expert groups by fve professors, three assocate professors and two coaches. Questonnare method It nvestgates the compettve ablty ndcators of the excellent women volleyball players; n order to ncrease the relablty of the survey, ths study uses resurvey method to test, the tme nterval of two surveys s 15 days; through the statstcs data of the questonnares, the correlaton coeffcent of the groups of data s 0.91, and the sgnfcance level s less than 0.01. Mathematcal statstcs In order to conduct quanttatve analyss of the ndcators, ths paper quantfes the es usng the fuzzy set method of fuzzy mathematcs and data standardza-
BTAIJ, 10(3) 2014 Lxn Wu et al. 623 ton methods, and uses EXCEL software and SPSS statstcal software for data processng. Analytc herarchy process In order to conduct unfed systematc analyss on the quanttatve and qualtatve analyss, the paper adopts AHP analyss, analyzes the mult-objectve and multcrtera comprehensve evaluaton system for the volleyball players. ESTABLISH THE COMPREHENSIVE EVALUATION INDEX SYSTEM OF VOLLEY- BALL PLAYERS Athlete s athletc ablty refers to the athletes ablty to effectvely partcpate n tranng and compettons; Volleyball Players athletc ablty n ths study can be analyzed from athletes physcal ftness, techncal and tactcal ablty, psychologcal qualty, sports ntellgence and other factors; the fve abltes exst dfferent levels of ft and constrants; n the tournament players can lay the foundaton for the fnal vctory only by applyng these qualtes scentfcally and tactfully. The establshment of volleyball players comprehensve evaluaton system can extract from the structure of sportsmen s compettve ablty; by the above analyss the structure of the athletc ablty s consttuted by physcal aglty, skll, ntellgence and psychology four-part; n the followng t extracts the comprehensve evaluaton es of athletes from the above four parts of the structure, conducts expert ntervews on the prmary ndcators after extracton, screens the ndcators n lne wth the prncple of scentfcty, testablty, relatve ndependence, objectvty and smplcty, and ultmately gets the comprehensve evaluaton system for volleyball players; there are four frst level ndcators, eght second level ndcators, sxty-two thrd level ndcators n the evaluaton system. Analyss on factors affectng volleyball player s compettve ablty The structure of athletc ablty s consttuted of the physcal aglty, skll, ntellgence and psychology four components; physcal aglty s manly reflected n the athletes specal physcal ftness, the level of physcal functon and physcal shape characterstcs; sklls are manly reflected n athletes ablty to use volleyball s specal technque and tactc; ntellgence s manly reflected n players tact behavor n tranng and competton; psychology s manly reflected n athletes control ablty to psychology; the followng analyzes the structural components of volleyball players athletc ablty, n order to provde a theoretcal bass for the extracton of athletes comprehensve evaluaton. 1) Physcal aglty As can be seen from the volleyball court, the physcal characterstcs of athletes shows a hgher consstency; from the structures of athletes body shape, the players are all very tall; ths tall body shape can be summarzed as heght, lmb length, short sttng heght, thn cortcal layer, bg physcal densty, small amount of body fat, wde hand, arm length, narrow pelvs, wde and not long foot, arch heght, length of the Achlles tendon and the features of 12 parts; such a body shape helps to mprove the offensve effect of servng; from the perspectve of physologcal functon, n the contest process athletes metabolc mean take the aerobc metabolsm functon as bass, take the anaerobc metabolsm functon as the core, the player need to have a good anaerobc metabolsm ablty; from the perspectve of qualty features, excellent volleyball players have better movement speed, arm swng speed, flexblty, endurance and jumpng ablty, these are the athletes physcal characterstcs; and health level s the bass of these features. 2) Sklls Techncal level of excellent volleyball players s manly reflected from the profcency of basc sklls, sold degree of basc sklls, comprehensve degree of techncal level, accuracy degree of the basc sklls and promnence degree of the characterstcs; n the evaluaton process of volleyball players athletc ablty, sklls lnk s the mportant part that cannot gnore; athletes need contnuous nnovaton n the process of technques and tactcs applcaton, and strve to become a player wth complete skll; techncal ablty s reflected n the grasp stuaton on the varety of techncal movements; and tactcal ablty s manly reflected n the ndvdual and collectve tactcs combnaton, tactcs nnovaton, tactcal theory and many aspects, etc. Therefore specalzed tranng for volleyball players s necessary.
624 Comprehensve evaluaton research of volleyball players athletc ablty based BTAIJ, 10(3) 2014 3) Intellgence In volleyball confrontaton process, teammates and coaches are not allowed to enter the venue; players need to control the court s envronment and compettve features, athletes need to have a hgher ntellectual level for the confrontaton project that have fast ball speed and more changes; ths ablty allows players be flexble and mprovse, thus the players can deal wth a varety of unexpected complexty n the game; the athletes reacton speed and ntellectual level nfluence the play effect of the sport s technques and tactcs. 4) Psychology Volleyball sports requre a hgher mental qualtes for players; n the confrontaton, when the pont loss, no good fghtng awareness and self-control ablty appear due to the players own techncal movement fault; when the stuatons of these psychologcal characterstcs arse, t wll have a sgnfcant mpact on the competton results; psychologcal qualty characterstcs of volleyball players s reflected n aspects of decsve degree to deal wth the problem, the degree of tact understandng to collaborate wth other team members, the ablty to mutually encourage and ncrease the confdence. Accordng to the relaton between the elements of athletes athletc ablty, t bulds the model structure to reflect the economc capacty, whch s the process to generalze, conclude and abstract athletes athletc ablty; Ths s the only way to reveal the overall level of volleyball players from a deeper level. At the begnnng of establshng the comprehensve evaluaton system of volleyball players, we need to screen the evaluaton ndcators n accordance wth the prncples of the scentfc, testablty, relatve ndependence, objectvty and smplcty. The screenng process and results of volleyball players comprehensve evaluaton Screenng process of ndcators s bult on the bass of the prmary ndcators; the study conducts questonnare survey of 90 prmary sngle ndcators and dvdes the mportance degree of each ndcator nto fve grades; the evaluaton language from excellent to poor are respectvely: very mportant, more mportant, mportant, general and unmportant; and set the weght 1,2,,5 scores of fve grades as n formula (1) below. 1 2 3 4 5 5 4 3 2 1 (1) The correspondng evaluaton language of each sngle ndcator has the above fve grades; each member of the expert group votes the mportance degree of ndcators n accordance wth hs own understandng, and then t conducts the data normalzaton process by row, the number of votes correspondng to s represented by ( 1,2,,90; j 1,2,,5), the n j correspondng evaluaton language level to j, the degree of mportance reduces gradually from 1-5; the score of the s mportance degree s shown n formula (2) below. 5 N nj j1 n1j Mark N 1 2 3 n N 1j 4 n N 1j T 5 n N 1j n1j N Usng ths method the Mark means the mportance degree of ths ; n order to further refne the comprehensve evaluaton system of volleyball athletes, t s dvded nto four frst-level ndcators as physcal aglty, skll, psychology and ntellgence; accordng to the mportance degree of the prmary elected ndcators, t uses the ndcators whose mportance degree s more than 4.0 ponts; the name, the mportance degree and the standard devaton of the fltered second level ndcators are shown n TABLE 2. After screenng there are total ffty-two remanng thrd level ndcators, dvde the symbols accordng to the second level ndcators, ts mportance degree and names are as shown n TABLE 3. Establsh the comprehensve evaluaton system for volleyball players Accordng to the ndcator screenng results n accordance wth the above mportance degree, the study conducts smple treatment on t, and we can draw the volleyball player s comprehensve evaluaton system as shown n Fgure 1. The structure of the comprehensve evaluaton sys- (2)
BTAIJ, 10(3) 2014 Lxn Wu et al. 625 TABLE 2 : The screenng results of the second level es under the Volleyball Players comprehensve evaluaton frst level Frst level Physcal es aglty-a Skll -B Second level es The correspondng mportance degree of the after screenng Standard devaton of the fndngs Body Shape -A1 4.69 0.947 Body functons -A2 4.38 0.768 Sports qualty -A3 4.77 0.439 Healthy level -A4 4.77 0.599 Techncal capacty -B1 5.00 0.000 Tactcal level -B2 4.58 0.555 Psychology -C Mental ablty -C1 5.00 0.000 Intellgence-D Exercse ntellgence -D1 4.77 0.439 TABLE 3 : The screenng results of the thrd level es for the Volleyball Players comprehensve evaluaton system Index Symbol Index Name Importance degree Index Symbol Index Name Importance degree A11 Heght 4.75 A31 30m 4.65 A12 length of upper lmb 4.69 A32 60m 4.85 A13 length of lower lmb 4.38 A33 V-Movement 4.69 A14 Hand length 4.62 A34 M-movement 4.85 A15 Span - Heght 4.15 A35 Prone and 20m runnng 4.46 A16 Shoulder rotaton dstance 4.00 A36 The touch heght when both Feet take-off 4.46 A17 Achlles tendon length 4.38 A37 Mean value of ten consecutve touch heght 4.85 A18 Foot-shape 4.38 A38 Run-up touch heght 4.77 A19 Body fat ngredent 4.00 A39 Standng long jump 4.46 A21 Mornng Pulse 4.31 A310 Badmnton throw 4.69 A22 Maxmum heart rate 4.77 A311 Deep squat 4.77 A23 Maxmal oxygen uptake 4.54 A312 1mn straght leg st-ups 4.62 A24 Blood testosterone 4.31 A313 30s double rock jump 4.08 A25 Blood lactc acd BLA 4.15 A41 Past medcal hstory 4.08 A26 Hemoglobn 4.54 A42 Sports Injures 4.38 A27 Vson 4.54 B11 Serve Technology 4.92 A28 Body functon 4.38 B12 Passng Technology 4.77 B21 The applcaton of offensve tactcs 4.62 B13 Ball dggng technology 4.92 B22 Ablty to mprovsaton 4.92 B14 Spke Technque 5.00 B23 Defensve and offensve tactcs 4.85 B15 Comprehensveness of techncal grasp 4.85 C11 Competton mood 4.92 B16 Effectveness of techncal sports 4.85 C12 Game motvaton 4.38 B17 Profcency of techncal acton 4.92 C13 Voltonal qualty 4.92 D11 Pay attenton to the qualty 4.15 C14 Self-confdence level 4.85 D12 Intellgence 4.77 C15 Central nervous fatgue 4.08 D13 Cultural level 4.38 C16 Sensory percepton ablty 4.23 D14 Professonal knowledge 4.15
626 Comprehensve evaluaton research of volleyball players athletc ablty based BTAIJ, 10(3) 2014 tem n Fgure 1 shows that the thrd level ndcators after smple treatment changes from the prevous 52 to the remanng 39; so ths study can be smplfed that A1, A2, A3, A4, B1, B2, C1 and D1 as the frst level ndcators, the correspondng thrd-level ndcators are the structure of second level es; accordng to the mportance degree the computng method of weght dstrbuton for the es at all levels are shown n formula (3), the formula (3) takes to the frst level ndcators as an example. Mark Mark A1 Mark A1 A2 D1 1 Mark A1 Mark Mark Fgure 1 : Herarchcal chart of volleyball players comprehensve evaluaton system A2 A2 Mark Mark C1 D1 Mark Accordng to equaton (3) we can calculate the weght dstrbuton condton of the eght frst-level ndcators after the smplcty, smlarly we can obtan the weght dstrbuton condton of each second level under the frst level es; so you can get the weght dstrbuton results of all levels of es as shown n TABLE 4. TABLE 3 shows that there are 42 evaluaton es as heght, arm length, length of lower lmb, spanheght, shoulder rotaton dstance, the Achlles tendon length, foot-shape, body fat ngredent, mornng pulse, heart rate, maxmal oxygen uptake, blood testosterone, blood lactc acd, hemoglobn, vson, body functon, 60m, m-movement, 20m run startng from prone, the run-up touch heght, average value of ten consecutve touch heght, standng long jump, badmnton throwng, deep squats, one mnute straght leg st-up, 30 seconds double shake jump, servng technque, ball dggng technology, passng technques, spkng technque, techncal sports results, compettons mood, game motvaton level, voltonal qualty, confdence level, sensory percepton ablty, central nervous fatgue, health level, the tactcal level and ntellgence level. D1 (3) COMPREHENSIVE ASSESSMENT METHOD OF VOLLEYBALL PLAYERS BASED ON FUZZY MATHEMATICAL MODEL The fuzzy set defnton of volleyball player s evaluaton The fuzzy set s dvded nto fve levels, respectvely very good L1, good L2, general L3, poor L4 and very poor L5; the centesmal system stpulates that the score range of very good s (90-100), the score range of good s (80-90), the score range of general s (70-80), the score range of poor s (60-70), the score range of very poor s below 60 ponts; the to be tested ndcators n ths artcle are dvded nto two types, one s the result of the questonnare survey, one s the result of test data; to quantfy the nvestgated ndcators results, t uses prncples of evaluaton language and correspondng scores, namely the correspondng value to very good s 100 ponts, the correspondng value to good s 90 ponts, the correspondng value to general s 80 ponts, the correspondng value to poor s 70 ponts, the correspondng value to very poor s 60 ponts. The treatment way of measurable ndcators can take the 0.5 tmes standard devaton, sgma, 1.5 tmes standard devaton, 2 tmes standard devaton, 2.5 tmes standard devaton and more than 2.5 tmes standard devaton as the evaluaton crtera; take heght for an example, the heght mean of excellent women volleyball athletes s 175.71cm, the standard devaton s 4.76cm, then the correspondng evaluated language for the athletes wth dfferent heghts s shown n formula (4) below. L1, L2, L L3, L4, L5, X 0.5 S, X 0.5 S X 0.5 S, X S X 0.5 S, X S X 1.5 S, X S X S, X 1.5 S X 2 S, X 1.5 S X 1.5 S, X 2 S (4) X 2.5 S, X 2 S X 2 S, X 2.5 S
BTAIJ, 10(3) 2014 Lxn Wu et al. 627 Frst level A1 A2 TABLE 4 : The weght dstrbuton results of all levels of es accordng to mportance degree Second level Weghts Frst level In formula (4) L represents the correspondng evaluaton language to the data of certan athletes, X means that the average value of the, S means that standard ndcators of test data; there are many ndcators wth hgh prorty, also there are many ndcators wth low prorty; durng volleyball exercse, the mean value heren taken n ths paper s the Second level Weghts Frst level A25 9.25 1.46 A312 47.5 4.5 D12 73.65 17.32 Second level Weghts A11 0.13 A32 0.12 C11 0.21 A12 0.11 A34 0.12 C12 0.20 A13 0.10 A35 0.09 C1 C13 0.23 A14 0.12 A38 0.10 C14 0.18 A15 0.11 A37 0.12 A3 A16 0.10 A39 0.11 A17 0.12 A310 0.08 A18 0.11 A311 0.09 A19 0.10 A312 0.08 A21 0.12 A313 0.10 A22 0.14 B11 0.23 A23 0.13 B12 0.23 A24 0.12 B1 B13 0.16 A25 0.12 B14 0.25 A26 0.11 B16 0.23 A27 0.13 A1 0.09 A28 0.13 A2 0.11 C16 0.18 A3 0.13 A4 0.13 B1 0.14 B2 0.13 C1 0.14 D1 0.13 data mean of the natonal excellent volleyball players; we take these data as a standard to evaluate other athletes, namely we take the data ndcators of elte volleyball players as a reference substance, and take the mean and standard devaton of dfferent multples as boundares of level classfcaton. To dvde the fuzzy level of the test data, ths paper obtans the mean value and standard devaton of each TABLE 5 : The mean and standard devaton of testablty data for excellent women s volleyball athletes Index Mean Standard devaton Index Mean Standard devaton Index Mean Standard devaton A11 175.71 4.76 A26 13.11 0.76 A313 62 3 A12 77.81 1.67 A27 73.14 3.53 B11 8.24 1.22 A13 104.10 4.96 A28 3.25 1.57 B12 9.34 0.34 A14 18.32 0.85 A32 8.52 1.41 B13 8.91 0.58 A15 5.24 2.64 A34 8.64 0.76 B14 9.33 0.32 A17 24.92 2.87 A35 3.44 0.23 B16 8.79 1.07 A19 15.67 3.51 A37 2.98 0.14 C11 52.83 2.67 A21 54.51 4.21 A38 2.96 0.25 C12 7.27 0.65 A22 186.12 6.83 A39 2.42 0.38 C13 38.13 4.21 A23 4.51 0.46 A310 8.32 1.76 C14 8.83 0.95 A24 93.64 5.47 A311 86.07 10.32 D11 55.94 24.60
628 Comprehensve evaluaton research of volleyball players athletc ablty based BTAIJ, 10(3) 2014 testablty data for excellent women s volleyball athletes as shown n TABLE 5. Fuzzy evaluaton step STEP1 Accordng to formula (4) the fuzzy evaluaton grade of the test data can be obtaned; STEP2 Accordng to the survey results the fuzzy evaluaton grade of the nvestgatve can be obtaned; STEP3 Conduct assgnment on to be measured ndcators n accordance wth the standard of formula (5); 100, L1 90,L2 Mark 80,L3 70,L4 60,L5 STEP4 Accordng to equaton (6) calculates the score of volleyball player s hgher level ; G Mark 1 Mark 2 Mark n 1 2 n And so we eventually obtan the volleyball player s comprehensve evaluaton scores n turn, and then need to compare the number of athletes, or the evaluaton grade of ndvdual athletes provdes reference for targeted tranng of athletes. CONCLUSIONS 1) Ths paper frst analyzes the requred sklls, character and qualtes of volleyball players n the confrontaton process, sums up the characterstcs of four aspects as physcal aglty, skll, psychology and ntellgence, provdes a bass for the extracton of athletes comprehensve evaluaton. 2) By analyzng the four aspects of physcal aglty, skll, psychology and ntellgence, ths paper obtans the prmary second level es and thrd level es under the four frst level es, and screens the prmary ndcators accordng to the mportance degree of the survey data obtaned n ntervews wth experts, and then uses smple prncples to conduct a secondary screenng for the (5) (6) ndcator system, obtans eght frst level ndcators and thrty-nne second level ndcators, and through analyss there are total forty-seven measurable ndcators; durng ths perod also obtans correspondng weghts dstrbuton of each, and provdes a bass for the rear fuzzy evaluaton. 3) It gves fuzzy set defnton wth the hundred-mark system and fve evaluaton grades, and provdes algorthm for the quanttatve analyss of each s test results n the system, fnally gves the algorthm steps of volleyball players comprehensve evaluaton based on fuzzy mathematcal model, and provdes a theoretcal bass for the reasonable evaluaton of the athlete. 4) Key content of ths study s the analytcal method on the system establshment, data quanttatve method and quanttatve es of volleyball players compettve evaluaton; the quantzaton process of ndcators can be dvded nto the ndcator quantzaton process of measurable data type and survey ndcators; the quantzaton process of measurable data uses the 0.5 tmes standard devaton as the way of level nodes, and combnes the data wth the hundred-mark system; and fnally by assocatng the data after quantzaton wth the prevous weght allocaton results, we can calculate the fnal score of players, and then we evaluate the athletes accordng to the range of the score. Advantages of ths paper s to extract the and establsh the system takng the nstance as object, and provdes a method for the establshment of athletes comprehensve evaluaton system, dvdes the quantfcaton process of ndcators nto two categores, and gves the comprehensve evaluaton algorthm based on the fuzzy mathematcal model. ACKNOWLEDGMENT The central unversty basc scentfc research busness specal fund, project number:heucf131602. REFERENCES [1] Sun Chun-feng, Yang Xao-yun; The Prncples of Mechancs for Spn Servce and Non-spn
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