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Tgp chi Khoa hoc Trudng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tv nhien, Cdng nghi va Mdi Irudng. 34 (2014): 33^4

Tap chi Khoa hpc Trirdng f)ai hoc Can Thd website: sj.ctu.edu.vn

^^.

PHAN TICH THONG K i D I N H LU TAI TRAM DO CHAU D 6 C TREN S 6 N G ILiU Va van Tai'

' Khoa Khoa hgc Tu nhien, Trudng Dgi hgc Cdn Tha Thong tin chung:

Ngdy nhdn: 14/08/2014 Ngdy chdp nhgn: 30/10/2014 Title:

Statistical analysis crest of a flood at Chau Doc's measuring station on Hau river Tic khda:

Chuoi thdi gian, chuoi thai gian md, dtr bdo, chu ky. lieu chudn AIC

Keywords:

Time series, model forecast, cycle, fuzzy

ABSTRACT

Using historical data crest offload at Chau Doc's measuring station on Hau river (CFCDHR) and basing on the autocorrelation coefficient cmd spectrum analysis, this study considered its cycle. Different models of time series and fuzzy time series were built from the original data, smooth data and frizzy data of CFCDHR. By using statistical criterions in order to find the most appropriate model the CFCDHR to 2020 was then forecasted.

T 6 M TAT

sa dung sd li$u qud khd dinh lU lgi trgm do Chdu Doc tren son^ Hdu (CFCDHR), dua vdo he sd lg- tuang quan, phdn tich pho, bdi viet xem xet chu ky cua no. Tie so li$u goc, so Uiu ldm tran, so li$u md hoa cua CFCDHR, bdi viit xdy dting cdc md hinh khdc nhau cua chuoi thdi gian vd chuoi thdi gian ma. Sic difng cdc tieu chudn thong ki di tim mo hinh thich hgp nhdt, tir do chung toi tiin hdnh dif bdo CFCDHR den ndm 2020.

1 G i d l T H i e U

Dong bing sdng Ciiu Long (DBSCL) la vya lua cua cd nude, vimg sdn xuit trilTcay quaii ttpng b|e nhit ciia qudc gia. Vdi dja hinh bing phdng, nhiiu viing ttiuig, CO nhieu sdng ngdi chang chit hdng ndm DBSCL ludn cd mpt miia lu tii toing 7 din todng 11. Lu mang din nhiiu lpi ich cung nhu ga;y ra nhilu tic hgi ve n^udi va eiia cho viing. Cd toi ndi Ijch su phdt triln kinh tl x i hpi cua viing DBSCL gin liin vdi Ijch sd phdng ching lu lut eiia ngudi dan. Ngdy nay, vifc ddi phd vdi lu gin liln vdi cic cym tir: "kilm sodt lii", "sdng chung vdi lu", tuy nhiin phuong cich dl touc hifn cic phuong cham dd cdn nhilu bin cii khdc nhau. Dl dii phd vdi lu toeo cich ndo, chiing ta diu cdn phdi dy bdo dupe chl dp toiiy van hai con sdng chinh Uong vimg: Sdng Hgu v i sdng Tiln.

Phan tich thong ke dinh lu tgi tram diu nguon sdng Hdu li co sd quan ttpng de dua ra nhiing phdn

tich tai ede vi tri khic ttong viing. Trong phin tich toong ke vifc dy bdo dmh lu, cung nliu xdc dinh chu kj' cda nd Id nhung cdng vifc quan ttpng nhdt.

Nd li ca sd khoa hpc can phai ed ttong qui hogch xay dyng vd phdt Uiln he toing toiiy lpi, sdn xuit ndng nghifp. Nd ciuig la co sd dl m5i dia phuong ldm cdn cu Uong xdy dyng cym tuyln din eu, phit ttiln dd thj,... Chung ta d i chiing kiln sy ling phi va hau qui vd cung tai hai cda nhtbig cdng trmh xiy dyng do khdng dy bao dupe dinh Ifi ciia cic dia phuong Uong vimg eic nim qua. Nghiin cdu ve dinh lu DBSCL tir lau d i dupe Phan vifn khio sit huy qugch Nam Bp, Dai khi tijpng thdy vin khu vye Nam Bd v i nhieu nhd khoa hpc toye hifn ttong cdc giai doan 1996 - 2000, 2000 - 2004, cdc bio cdo vl lu ldn 1984, 1991, 1996, 1997, 2000,... vd rat nhilu bao cdo toudng niln khdc. Cic nghiin ciiu ndy dupe tdng kit ttong [13]. NbOng nghiin eiiu Uin cung da touc hifn dy bao dinh lu, tuy nhien toye te cho thay cic kit qua nay cung chi Id

Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tho Phdn A: Khoa hgc Tu nhiin. Cdng nghi vd Mdi trudng: 34 (2014): 33-44 tiidng tm mang tinh chit toam khio. Vifc dy bio

dinh lii cung nhu xac djnh chu ky eiia nd vdn la bdi toan khd chua cd ldi gidi cudi ciing. Cac phuong phdp todng kl hiln dgi ttong xic djnh chu k^", du bdo chuoi sd lieu todi gian di dupe dp dyng tuang doi tot cho cic bd so lifu khic nhau Uong cac nghien ciiu [2], [3], [4], ...'[9] nhung ehua dugc ip dung d nude ta.

DBSCL la mdt trong nhihig noi chiu dnh hudng n$ng nl nhat cua biln doi khi hdu. Cung vdi cac nhi khoa hpc uin toi gidi, cdc nhi khoa hpc Vift Nam dang gap nit xdy dyng nhung phuong phip dl ling phd vdi sy biln ddi cua khi hau. Bii vilt kit hpp md hitto chudi todi gian md vi khdng md.

Cling vdi nhiing phuang phdp xu ly sd lieu ban diu dl thyc hiln dy bio cu thi dmh lu, xdc djnh chu ky ciia nd tgi ttam ddu nguon Chiu Ddc. Day li nhflng

r(^k) = 1 %^(-^t-^o)(^t+k-^k^ ^ _L."j:^^!ll±kZ^!£k_

n-k t=l sr^s. n-k t=l SnSi^

nghien cihi quan ttpng de nghiin ciiu tdng toe touy van DBSCL phuc vu cho cac quy hoach ngan han ciing nbu ddi hgn Uong xay dung phit triln kinh tl xa hdi todn viing.

2 PHlTONG PHAP XAC © m H CHU KY VA CAC MO HINH DU" BAO ©INH LU

2.1 Phmmg phap sac dinh chu ky dinh lii Xet chudi todi gian dinh lu toeo nam { x , , / = ! . . « } , chiing ta cdn tira chuky A: ciia dinh lu nay, Theo [6], ttong todng kl ta cd 2 phucmg phip chinh de touc hiln: Sii dung him ty tuong quan va phuang phdp phin tich phd.

2.1.1 Su dung hi so tir tuang quan Hf sd ty tuong quan eiia chuoi thdi gian dinh lu dupe xdc dinh bdi cdng toiic:

(I) 1 n-k

--— s

n-k t=l 'k

S x,;x^ = 1. _Xf, S(.

n-k /=A+1

I " ^ ^ — 2

^iXf-XQ) , n-k 1=1

1 ^ — 2

— L (Xf -Xt) k = 1,2,...,m (don vi tinh la nara).

n-kt=k-\-l "

Gii tti k irng vdi r(lc) khi ldn hoac gin bing 1 se dupe xem li eic chu ky ciia chuoi dinh lu.

2.1.2 Sir dung phuang phdp phdn tich pho Mgt dp phd dupe xic djnh nhu sau:

1 m jik 5 ( % ) = - I fi(r)cos—r

" a-r=0 m (2) Trong dd T la budc Uupt ciia ham ty tuong quan (j = 1,2,3,..., ffl); m li so gii ttj hamty

'max Ar

vdi r „ . la tucng quan can ti'nh; m -

budc trupt ldn nhit vd A? la budc todi gian ciia chuoi X,, \ la tin sd mat dp phd cd cdng toiic

27ik 2nk

Phd tinh toin tii sd lieu toye ed toe cd nhihig sai Ifch, nln ngudi ta dimg hdm cua sd dl lam tton

vi gidm dd sai lech niy. Cd nhieu ham cda sd dupe su dung nhu hdm Bartiette, him Hamming, ...

Trong bii viet nay, chung tdi sd dung cua sd la hdm Tukey - Harming:

Dua ham cua sd nay vdo (2), khi dd ta dupe:

S(i^)-2 fi(0)+ S w{T)R{T)a 7lk (3)

Phd chuin hda dupe xic dinh bdi cdng toiic:

six,). s(4) ^{% 7rk}

1+ S M<r)/-(r)cos—r (4) Sii dung tilu chuin Tukey de kilm tta chu ky A cd y nghia todng kl khdng. Trong kiem dinh nay gid tt; tdi ban dupe xac dinh la

Tgp chi Khoa /ipc Trvmg Di/i hpc Can Tha

(„(s,) = sA

^ „ ( m - l ) -

(Sx la trung binh cua m gia tti mat dp tliirc ngtiiem; v la bac tu do;

Phin A: Khoa hoc Tv nhiin. Cong nghi va Moi Iruang: 34 (2014): 11-44 2.2.1 M6 hinh chuSi thai gian khong mi Mo hinh Ur h6i qui bdc p (ARfp)):

p

y , ^ " ' " - " " . Niu i(4)<«„(5,)tW ph6 m

khdng ed ^ nghia hay chudi todi ^an dinh lii khdng cd chu ky k.

2.2 Dy bao bing md hinh chuSi thdi gian Voi sd lifu toeo todi gian, ttong todng kl ed hai phuang phip ca ban thyc hiln vile dy bdo: Sii dyng md hlnb hdi qui vi chudi thdi gian. Vdi sd lifu biln ddi phiic tgp nhu dmh lii sdng Hiu, vile dy bio tiieo phuong phdp hdi qui khdng cho kit qud tdt, vi viy vifc dy bdo d day chi toye hifn theo cdc rad hinh chuoi thdi gian md vd khdr^ rad, Uong dd chd ttpng vile xd ly sd Ufu ban diu (ldm tron, md hda) trudc khi dy bdo.

ttong do ^, Id cic he sd udc lupng cda mo bmh, u, la sd hang dim bao tinh dn tting.

Mo hinh trung binh di dgng bdc q (MAiq)):

y.=^o+T^,"'-'

⁽⁶⁾

trong dd /^ cung li eic hf sd udc lupng cua m6 huihvi w, gidng nhu Uong (6).

M6 hinh ty hii qui v i trung binh di dfng (ARMA(p,q)):

=A +^iyi-i +^2y,-2 + - + ^ p 3 ' , - p + " , + A « M + A " , - 2 + - + ^ , " i - (7) Mpt qua trinh ARMA(p,q) se ed qud ttinh ty hoi

qui bge p va qua trinh trung binh di ddng hie q.

y,=^S + a^y,_, + a , X - 2 + - + ^^^X-p + A + ^ M +- + fig^,-<, + ^ /

Md hinh trung binh di ddng tdng hpp vdi ty hdi qui ARlMA(p,d,q):

(8) trong dd Oj,! = \,,2,...,p la toam sd ty hdi

qui; o, ,,y = l,2,...,9 Id toam so trung binh di dpng; S = p(fiy + fi2+-+fiq)'- M la gid tri Uung binh cua chuoi todi gian; e, li sai so dy bdo {e,=y,-y,= ^h lifu dy bdo - sd lifu toye tl).

2.2.2 Mo hinh chuoi thdi gian ma Abbasov- Mamedova

Mo hinh ehuSi thdi gian md niy gim 6 budc nhu sau:

Budc 1: Xdc djnh tap nln U chiia dogn thdi gian giua cic biln ddi nhd nhat va ldn nhit ttong chudi dii lifu.

Budc 2: Chia tip U toanh n doan thdi gian ed dp dii bing nhau chda eic gid trj bien ddi tuong ling vdi ty If ting trudng khic nliau ciia dinh lii.

Ddng thdi tinh cae gii Uj trung binh eua tiing dogn ( M ^ , I = l , . . . , w j .

Buac 3: Mo td chdt lupng eua cac gii Ut bien ddi dinh lu ttou Id mdt bien ngdn ngu:, xic djnh cic gid trj tuong Omg ciia biln ngdn ngii ho&c toilt l|p cdc tdp md F(f):

^'=["'<,• ("'•)'"4"'^'^""4^'°''^' ^4-("''^'

1

\c^[u-J„,)\

⁽⁹⁾

^, ., , , • , _ , , chuyen dot cdc gia tn so vao cdc gia Uj raa. Hogt Uon£ dd A la ma hoa cac bien cua nam (; C la *- . L , ^ i . • , ._ . •» x_- uuiifi uu yi la iiiu iiua i-o^, uicu i,ua iioiii , v- va. ^^^^ ^^^ ^^^ pj^^p ^^^^ ^^ ^^ tUOUg ling g i i ttj hing so ty chpn sao cbo //^ (u,) e [0, l ] ; U la djnh lupng hay djnh tinh ciia ^ 11 phat ttiln dinh lu cdc biln ddi eiia timg nam, hogc Ii gii uj tmng tieu bilu ttong gia tti cua hdm quan hi.

binh; w^ la gii trj trung binh ciia timg dogn tod i Buac 5: Lya chpn toam sd w(l < w < w); n Id Buoc 4; Md hda cac dfl lifu diu vdo hoic =^ " ^ ^"^ ^^ ''^" ^^ '^^u ^ « " g *^g v<^ ^""^

35

Tgp chiKhoa hgc Trudng Dgi hgc Can Tho Phan A: Khoa hgc Tu rAiin, Cong nghi vd Mdi Irudng: 34 (2014): 33-44 thdi gian trudc idii sang nam cd Uen quan, tmh toan

cic mdi quan hf md cua ma tran P''{T).

«(0['.y] = o-[/.y]n*:(<)[j]

Hay

R{t) = o"({)%K{i)-

"n "n •

- " 2 1 ^ 2 •

•"il "il •

• hj

• ^-

ttong do i = l,...,w',j^l,...,n.

Budc 6: Giii md kit qua thu ducrc hogc ehuyin ddi cac gii tti md vao cdc gia Uj djnh tinh. Dy bao cho nam tdi

..R,^)...max[R^J,R^J,...,Ry)

, , Xj^,("ih-'m

| . ( . )

⁽¹⁰⁾

Kit qui dy bdo cho nam tod t dupe tfnh toeo cdngtoiic: N{t) = N(t-i}-\-V(t) (11)

trong dd N(t) l i dinh lu eua nam t, V(t) la dinh lu thay ddi td nam t -1 din nam /.

3 XIJ* LY SO LIEU BAN DAU TRONG DU" BAO 3.1 Lam trou so lieu

Lim tton la phuang phap cd diln dl xir ly sd lieu ban dau ttong dy bio, toy nbiln cho din nay nd ciing dupe ip dyng phd bien ttong todng kl, dgc bift cho cae sd lieu phiic tap cua thiiy van.

Theo [5] vd [6] cdc phuong phdp lim tton chii ylu nliu sau:

•3.1. L^ Phucmg phdp trung binh trugt fl. Trimg binh trucrt dan Cdng toiic:

7 - I ' ^ - " ^ V i V + l ^ M,

N

-M

⁽¹²⁾

Trong do M ; li trung binh trupt kep.

L.. Trung binh tru0 trung tdm

Trung binh trupt trung tam ciia todi ky hien tai / dupe liy vdi ed todi ky trudc va sau, ddi xiing qua/.

- Nlu L le thi trung binh truot trung tam dupe tinh bdi:

j ^ ) (14) 2

Trong dd M, la trung binh trupt cda Af thdi ky;

x^Xt-i, ...,x,.N+u cac gii tti cua chudi tai iV todi 1^

vl phia truac.

b. Trung binh trugt kep

Trung binh trupt kep la ttung binh trupt ciia trung binh trupt don, nghia l i tCr tnmg binh ttupt don tmh liy trung buih trupt mdt lan niia. Khi

x' 1 = s^ =at + {l- a)x._, + a(l - a ) x. 2 Ml 1

^tl ^T^\ i ^ i + . . . + x^+... + x

L t-^^ t Trong do J:, la dilm gifla khodng L cdc quan ae.

- Nlu L chan toi ti'nli theo hai budc:

Tinh 2 tnmg binh trupt bao quanh khoang L:

m.^=-{x J ^...+ Xj+... + x j), '^ L t~^\ t ^ M y = - ( i , +„. + :,:,+... + JI; , )

Trong dd A/JJ^, M^^ la cac Uung binh tiirpt don bao quanh khoing L.

Khi dd trung bmh trupt trung tdm ciia chudi dmhiux,li-(_M;|^+Af;j^).

3.1.2 Phucmgphdp hdm mH

Chudi todi gian dinh lu x,+i dupe xdc djnh bdi cdng toiic:

. 2 - f . . . + a ( l - a / - l x , (15)

Tgp chi Khoa hgc Trudng Dgi hgc Can Tho Phan A: Khoa hpc Tu nhiin, Cdng nghi vd Mdi irudng: 34 (2014): 33-444 Trong do a li hang sd ldm uon, a e (0; 1].

Thdng toudng dupe liy tir O.OI den 1.00.

a. Hdm mu dan

Thyc hifn cdng thuc (15) d dgng truy hdi.

Xuat phit tii gii trj ban dau 5o, ta cin xic dinh hing sd lam tton a . Gia tri a duac xac dinh sao cho tdng binh phuang sai sd Y.{Xf-x'j) hay

£ {Xf - s._,) nhd nhit. Kit qua cua rang bupt 2 2

ndy cho ta gia tti cua a la a = vdi L li do L + l dai thdi ky lam tran. Ude lupng ban diu so thudng dupe liy bing trung binh sd hpc ciia ci chudi.

b. Ham mU kep (Phuang phdp Brown) Dii vdi chuSi c6 xu the tuyen tinh, gid tti thyc hifn toeo phuang trinh

x P = f l x , + ( l - a ) x J 3 (16)

, ( 2 )

Trong do X, li gid uj ldm tton hdm mu kep; X, Id gia ttj Idm tton him mu don, dupe tinh tiieo (16).

Gii Uj ban diu so dupe titto bdi 1 - a

XQ=a- (2) 2(1 - a ) ^

\x) ' =a b Trong dd a, b Id cie hf so xic djnh toeo hoi qui tuyen tfnh gifla eic gii tti ciia chudi vd ciia thdi gian l:xt = a + bl.

Doi vdi chuSi cd xu toe dudng cong bic hai thi xj^' = oxf ^ + (1 - a)x;_^,', ttong dd xf* li gid Ui ldm tran hdm mu kip, x, va x, Id cic gia trj Idm Uon tinh tiieo (15) vi (16).

Cdc udc lupng ban diu tinb nhu sau:

l - a ^ ( l - a X 2 - a ) ^ -26.,, 2 a ' ( 2 ) _ 2(1-g) ^ 2 ( l - a X 3 - 2 a ) ^ .(3)

xA ' = f l -3 ( 1 - a ) 3 ( l - a X 4 - 3 a ) 2a

26,, Trong do a, bi vd bi Id cic hf sd hdi qui bic hai ciia chudi sd lieu vdi thai gian t:

p nen U trin cic ciia chudi todi Xl = fl + *i^ + bih.

3.2 MIf hda sd lieu

Hiln tai cd nhilu md hinh md hda sd hfu, Uong thyc nghiim ta toudng sii dyng md hinb c ^ Huamg [4], Chen [9], Chen-Hsu [10] va Sin^

[12]. Cic md hinh niy deu gdm 4 budc thyc hiln, Uong dd cd 3 budc diu gidng nhau chi khac nhau d budc cudi ciing: md hoa dd lieu. Ba budc chung cda c ^ md hinh dupe dl nghj nhu sau:

Biwc 1; Xic djnh gia Ui lich sii

gian:U = lD^^-D^;D^-i-D^],tTong 6dD^„, Z>^ lin lupt la gid tri ldn nhit vi nhd nhit cua chudi du lifu, Dl, Dl la cic sd duong thich hpp dupe chpn.

Budc 2: Chia tip t/toinh timg doan toich hpp va deu nhau U.,U-,...,U . Xic dinh cie tip md

1 2 n '^

A^ tucmg ling vdi U^. Nlu A^ li gii trj md hda tgi todi dilm t •va A li gid tri md h6a tgi todi diem t +1 toi id cd mdi quan he md

^i-

Budc 3: Xdc djnh cic nhdm quan hf md.

Budc eudi ciing cua timg md hinh dupe de nghj e\i toi sau:

3.2.1 Mo hinh ciia Chen

Nguyen tdc 1: Nlu A^ li gia trj md hda tgi todi dilm t vd chi cd mdi quan hf md duy nhat li A-^ -> Aj till gia tri dy bio tgi todi diim t +1 la m {m la dilm giiia ciia doan t / ).

Nguyen tdc 2: Nlu A^ la gid ttj md hda tgi tiidi diem t vd cd nhdm mdi quan hf md Id Aj -^ Aj,Aj^,A^,... toi gid trj dy bao tai thdi dilm j^+l li Uung binh cpng ciia 771 ,m^,m,,...

imj,m^,m,y...la dilm gifla eiia doan

Nguyen tdc 3: Nlu 4 la gia Uj md hda tgi tiidi dilm / va khdng tdn tgi mdi quan he md ndo tbi gjA tri dybao tai todi d i l m / + l la m .

Tap chi Khoa hoc Tniang Dgi hpc Cdn Tha Phdn A: Khoa hoc Tu nhiin, Cong nghi va M6i trudng: 14(2014). 13-44

3.2.2 Mo hinh cua Singh k+lla A;^>A:

Voi *: = 3,w,maiquanMm6cuaphJntiJrtva y ^ ;? = 0,S = 0, tinh cac gia tri sau:

^/=N-^-l|-

\,X.=E,+-!-,XK,=E,—'-,Y,=E,+D,,Yr, = E,-D.,P,=E,+—,PP,=E,—'-

\ I ' 2 2 4 4 R+M(Aj)

S+1 2;=^.+2x1)., ag. = £;.-2xDj,G,. = £,.+-i,Gq.=£,—•-,H.^Ei+3xDi,mi = E^-3xDj;Fj

Trong do £,-, £ , _ , , £,._2 ijn lugt la gia tri t^ ^ ' ™ ' + ' •

tk«; ^ : i r „ I . t t ', A A I' I Khi do ta co cac nguyen tic ma hoa diJ lieu thoidiemr, r - 1 , / - 2 ; y 4 , yl lanlu(;rtlagiatn mo . ^^ ^ J ^ to . nhu sau:

t^i th&i di^m t, t +\ ;F. Ia gid trj dir bao tai thai

>R=R + r,,S = S + \;

rrjeUj^R = R+W.,S = S+\;P^eUj=>R = R+Pi,S = S+l;PPjSUj^R = R+PPj.S = S+l;

QieUjSR = R + Q^,S = S + l;QQieUj=>R = R + QQi,S = S + \;GieUj=>R = R + Gi,S = S + i;

GG,.£i7y=>« = R+GGj,S = S + l ; H , e £ / - ^ « = /i+//,.,S = S + l;HH,.eC/.3X = ;! + HH,.,S = S + l 3.2.3 Mo hinh Heuristic

Ta CO gia tn maF(f)c6 nhom quan he maAj--^Ap,A^,A,.,Ag,...vk ham Heuristic h(.x;Ap,Ay,A,.,A„...) = A^^,A^.^,...,A^^Min x = X(t)-X(t-\). Neu x > 0 dii p^,P2,:;Pi^^J, ngugc lai neu x<Q thi p^,P2,...,p^<j. Khi d6, niu j : > 0 flil '*J^^pV^p2--'*pk ™ Pi'Pl'-'Pt^J'

P],P'),—,Pi. ^j- Nguyen tic md hda du heu tuong tu md hinh cua Chen.

4 TONG QUAN VIEC THV"C HIEN 4.1 Muc tilu

Sii dung so lifu ciia qua khii vl myc nude cao nhit hdng nam tten Uam diu ngudn ciia sdng Hau (ttgm Chdu Ddc), xdc dinh chu kj dinh lii, tim md hinh chudi todi gian dy bdo thich hpp nhat, tir dd

dy bio dupe raye nude cao nhdt tai trara do ttln cho nhung nam tiep toeo Idm ca co sd cho cdc qui hogch trong xiy dyng, ttong phat triln kinh tl vT md ciia viing.

4.2 So lifu

Sd lieu dupe cung cdp tii Trung tdm dy bio khi tuong khu vyc Nam Bd dit tai Thdnh phd Cdn Tha. Cy toi tai tram do Chiu Ddc, chiing ta sii dung sd lifu muc nude cao nhit ciia 23 nim (giai dogn 1990 - 2012) de thyc hifn vifc nghien ciiu.

Bang 1: CFCDHR giai doan 1990 - 2012 -—r,iTNam:^T^^^-Murc nude

9 9 0 " " ^ ^ 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001

N i m M y c nurdc 386

427 289 309 419 391 454 379 255 384 490 447

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

442 347 402 390 370 356 320 352 377 427 398

Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tho

200 -

O rN ^ U) U C

S^ 8i 8^ 8 3) E

iH 1-1 T- ^TH rH r-

rst ^ ID 00 O M

8 8 8 8 0 0

(M rJ PJ pg rM CN

Hinh 1: Bilu Hh eft CFCDHR giai doan 1990-2012

43 Phinnig phip thyc hifn

Vdi sd lifu Bing 1, nghiin eihi lan lupt thyc hifn nhihig cdng vifc sau:

a) Kilm tra dfl lifu bat toudng toeo nguyin tie 3 xichma.

b) Xic djnh chu ky dinh lii bang phuong phdp hdm ty tuong quan vd phdn ti'ch phd vdi miie y nghia 5%.

c) Tim md hinh tdi uu nhit cho dy bio vi tien hdnli dy bio dinh lu den ndm 2020. Cu tiie cdc budc sau dupe thyc hiln:

i) Ldm tton dfl lifu gdc bing phuang phdp trung binh trupt don, trang binh trupt kep, trung binh trupt trung tim vi phuang phip hdm mu don, ham mu kep. Md hda dfl lifu gdc theo md hinh eua

" B i n g j ^ ^ f s i ty tiwrng quan CFCDHR vdi r ^ = 15

Phdn A: Khoa hgc TV nhien. Cong nghi va Mdi trudng: 34 (2014): 33-44 Chen, Singh, Chen-Hsu v i md hinh Heuristic. Sd dung tieu chuin sai sd tnmg binh be nhdt dl chpn bp sd lieu tdi uu.

ii) Xiy dyng md hbh cua chudi todi gian tii bf so lieu gdc, tir cdc bp sd lifu cua da tiiilt lap Oxjng i). Sii dung tilu chuin AIC [3] dl lya chpn md hmh tdt nhit cho dy bio.

iii) Sii dyng md hinh chudi todi gian md Abbasov-Maraedova de dy bao.

iv) Kit hpp ii) va iii) Ah^ chpn md hinh tdt nhit, tir dd dy bao dinh lu din nim 2020.

Vifc xiy dyng cic md hlnli chudi todi gian cy toi tii sd lifu, cQng nhu vile tinh chi %o AIC cho mdi md hinh dupe thyc hien bing phdn mim todng ke R, philn bdn 2.0.

S KET QUA T H V C HIEN 5.1 Kilm tra dii- Iilu bat thudng sip xip ehuSi sd lieu tiieo tiiii ty tang ddn, qui tic 3 xichma cho ta gid trj cua dfl lifu ttong khoang (216.53; 549.65). Sd lifu qud khii ciia dinh lii sdng Hiu diu ndm trong khoing niy, nhu viy ta khdng cd dfl lifu bat thudng.

5.2 Xic dinh chu kjr dii lifu 5.2.1 Phuong phdp hdm ty: tucmg quan Tu sd lifu ta tinh dupe ;c = 383.09, Var(A) = 3082.54. Vdi ^ , ^ = 1 5 , ;„ = Z^?=L = i5,

A/

A/ = 1 nam, bf sd ty tuong quan r ( r ) theo (1) dupe tinh cu the Uong bing sau:

r

/•.w

r

'iW

1 0.1945 9 -0.1174

2 -0.331 10 0.2397

3 -0.3043 11 0.3826

4 -0.1888 12 -0.2084

5 0.3712 13 -0.4692

6 0.2109 14 -0.118

7 -0.3994 15 0.5718 Bdng 2 cho ta thdy hf sd ty tuong quan cao hon

d cdc chu ky 5 nim, 11 nim vi 15 nam, ttong do eao nhit li chu k)' tuong img r = 15 nam vdi he

so tuong quan 0.5718. Tuy nhien, hi sd tuong quan niy cun§ nhd hon nhilu so vdi 1, nln khdng cd ^ n^Ta todng kl.

Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tv nhiin, Cong nghi vd Mdi Irudng: 34 (2014): 33-44

Hinh 2: Dd thi ty tuong quan cna CFCDHR vdi r kit qua tdng hop sau:

5.2.2 Phuang phdp phdn lich pho Sii dung cic cdng thiic trong phdn 2.1.2, ta cd

Bang 3: Phd chuaa hda vi chu ky dao dfng eua CFCDHR vdi r^^j^ =

sW sW

0.273 0.5461 0.8191 1.0922 1.3652 1.6383 1.9110 2.1843

1.4200 2.0476 1.9294 1.9905 3.6503 4.7230 2.1272 1.3851

23.0000 11.5000 7.6667 5.7500 4.6000 3.8333 3.2857 2.875

9 10 11 12 13 14 15

2.4574 2.7304 3.0035 3.2765 3.5496 3.8226 4.0957

1.2723 1.9822 2.209 1.7906 1.1935 1.2512 1.0238

2.5556 2.3000 2.0909 1.9167 1.7692 1.6429 1.5333

2n-0.5m 2x23-0.5x15 m 15 si =1.9997, ;fjj5(22) = 33.9245 Gid trj nguong trong kiem dinli Tukey la

2 /„(s^) = :rA—= 26.4.

Cdc gid tri ph6 chudn hoa s(..^f.) trong Bang 2 d£u nho hon nguong ciia kiem djnh Tukey. Dieu 66 CO nghia la cac gid tri pho tinh dugc khong co y nghTa thong k6.

Tdm lai: Ca hai phirong phdp thuc hien a tren deu cho ta k^t ludn khong ton tai chu ky ro rang cua dinh lu song Hau.

5.3 Mo hinh tSi uu dir bio dinh lii a. Mo hinh chudi thai gian tir sS lieu gdc Til so lieu Bdng 1, kiem tra ta co so lieu dung o sai phdn bac 3. Qua do thi ham ACF va do thi P/<Cf ta xac dinh du(ic dp t r i p = l , 2 , 3 ; j = 0, 1, 2, 3 , do d6 cac m6 hinh co the cho vi?c dir bao la ARIMA(0,3,1); ARIMA(0,3,2); A1UMA(0,3,3);

ARIMA(1,3,0); ARIMA(1,3,I); AR1MA(1,3,2);

ARIMA(1,3,3); ARIMA(2,3,0); ARIMA(2,3,1);

ARIMA(2,3,2); AR1MA(2,3,3); AR1MA(3,3,0);

ARIMA(3,3,1); ARIMA(3,3,2); ARIMA(3,3,3).

Tinh chi s6 AIC ciia cac mo hinh tren ta c6 bang tong hop sau:

Bang 4; Chi so AIC cac mo hinb dy bao ctia CFCDHR tik sa lieu g6c

Md hinh AIC

ARIMA(0,3,1) AR1MA(1,3,1) ARIMA(2,3,1) ARIMA(3,3,1) AMMA(0,3,2) ARIMA(1,3,2) ARIMA(2,3,2) ARIMA(3,3,2)

252.39 251.44 249.14 250.9 243.67 245.61 250.81 252.22

ARIMAC0,3,3) ARIMA(1,3,3) ARIMA(2,3,3) AMMA(3,3,3) AWMA(1,3,0) ARIMA(2,3,0) ARIMA(3,3,0) AR1MA(0,3,3)

245.49 245.77 246.65 248.27 262.37 255.59 257.42 245.49 Bang 4 cho ta mo hinh ARIMA(0,3,2) co AIC nho nhat, nghia la khi su dung dil lieu goc mo hinh nay toi uu nhdt

b. Mo hinh chuoi thai gian tit so lieu lam tran Tir so lieu gfic, lam tron theo phuong phap trung binh tiuot va ham mu boi cac cong thiJrc trong 3.1, ta tinh duoc bang tdng hop sau:

Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tho Phdn A • Khoa hgc Tu nhien. Cong nghe vd Mdi Iru&ng: 34 (2014): 33-44 Bing 5: So Iilu CFCDHR qua cic

S6 li|u ?6c Nim 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Q(cm) 386 427 289 309 419 391 454 379 255 384 490 447 442 347 402 390 370 356 320 352 377 427 398 ME

phmmg phap lim tron Tnnrtdffn

4 nam

352.75 361.00 352.00 393.25 410.75 369.75 368.00 377.00 394.00 440.75 431.50 409.50 395.25 377.25 379.50 359.00 349.50 351.25 369.00 388.50 39.70 Thuc hien cac buoc nhu dO lieu Bing 6: Chi

Mo hinh ARIMAT(0,

7 nam

382.14 381.14 356.57 370.14 396.00 400.00 407.00 392.00 395.29 414.57 412.57 393.43 375.29 362.43 366.71 370.29 371.00 40.08 goc, ta ct

Triurt Mp 4 nam

364.75 379.25 381.44 385.44 381.38 377.19 394.94 410.81 418.94 419.25 403.38 390.38 377.75 366.31 351.25 369.00 388.5 46.23

7 nim

384.76 386.16 388.18 396.47 402.53 402.16 398.80 392.22 388.60 385.04 378.88 35.19

^ (.^(. m6 hinh co the bai

Truot trun2 tim 4 nam

356.88 356.50 372.63 402.00 390.25 368.88 372.50 385.50 417.38 436.13 420.50 402.38 386.25 378.38 369.25 354.25 350.38 360.13 378.75 34.61 va chi so.

bdng tong hop sau:

7 nim

382.14 381.14 356.57 370.14 396.00 400.00 407.29 392.00 395.29 414.57 412.57 393.43 375.29 362.43 366.71 370.29 371.43

45.21 Himmu

383.09 405.00 347.00 328.00 373.50 382.25 418.13 398.56 326.78 355.39 422.70 434.85 438.42 392.71 397.36 393.68 381.84 368.92 344.46 348.23 362.61 394.81 396.40 23.9 AIC tuong ung dugc cho so AIC cac mo hinh dy bio CFCDHR tir so lifu lam tron theo phunmg phap ham mii 3,1)

AR1MAT(1,3,1) AR1MA-K2, 3,1) ARIMATC3,3,1) ARIMAT(0,3,2) Ai<lMAT(l,3,2) AR1MAT(2,3,2) AWMAi(3, 3,2)

AIC Mo hinh 216.81 ARIMAi<0,3,3) 218.25 A M M A T ( 1,3,3) 216.74 A]11MAT(2,3,3) 217.87/ ARIMAT(3,3,3) f- 213.22 ARlMAT(i,3,0) 219.44 AR]MAT(2,3,0) 218.75 ARIMAT(3,3,0) 219.94

."-^'

AIC 212.98 213.41 215.14 216.39 226.76 223.71 225.25 Bing tong hpp nay cho ta md hinh tdi uu li

AR1MAT(0,3,2) vi cd chi sd AIC nhd nhit.

c Mo hinh chuoi thai gian lit so li$u ma hoa

Md hda tii du lieu gdc toeo md hinh cua Chen, Singh, Heuristic vd Chen-Hsu ta cd bdng tdng hpp tinh toin sau:

Tgp chi Khoa hgc Trudng Dai hgc Cdn Tho

Bang 7: K i t qua md boa du- Iilu bing i 2012 CFCDHR

Phdn A: Khoa hgc Tunhiin, Cdng nghi vd Mdi trudng: 34(2014): 33-44 3 hinb Chen, Singh, Heuristic va Chen-Hsu giai doan 1990 -

N a m 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 ME

(cm)

500 n 480 460 • 440 420 400 380 • 360 340 320 300 • 280 260 240 -t

1

Gii tri Thirc tl 386 427 289 309 419 391 454 379 255 384 490 447 442 347 402 390 370 356 320 352 377 427 398

—•—Gi'a tri thyc —i

— * — Singh

1

990 1993

. . .

₁₉₉₆

Chen 372.5 349.0 349.0 396.0 349.0 372.5 419.5 372.5 349.0 372.5 419.5 419.5 349.0 396.0 349.0 372.5 372.5 372.5 396.0 372.5 372.5 349 42.45

»"Chen X— Heuristic

*,/ — ^

t Ir/ \

\\.«// ^

iv»

1999 2002 N a m

Singh

320.35 423.25 373.25 469.75 368.50 278.50 362.75 466.50 471.07 425.69 326.75 428.25 380.77 375.77 372.21 335.83 374.17 356.45 408.75 422.94 17.38

2005

Heuristic 419.5 349.0 349.0 396.0 349.0 419.5 419.5 325.5 349.0 419.5 466.5 419.5 349.0 396.0 349.0 419.5 419.5 325.5 396.0 419.5 325.5 419.5 38.30

V U V ^ ^ U *

1 1 1 1 , 1

2008 2011

Chen-Hsu

278.50 325.50 407.75 390.13 466.50 378.38 278.50 378.38 478.25 466.50 431.25 313.75 407.75 390.13 363.69 354.88 313.75 354.88 375.44 431.25 407.75 9.27

Hinh 3: Hinh ve cho so li£u mfr h6a CFCDHR giai do^n 1990 - 2011 theo cic mo hinh ciia Chen, Singh, Chen-Hsu v i Heuristic

Vi s6 lieu CO duoc tir mo hinh Chen-Hsu cho ta ME nh6 nhdt, nen chiing ta sii dung bp da Ii|u nay

cho du bdo. Ciing thuc hien nhu so liSu gfic, ta duoc cac mo hinh co the va chi so AIC nhu sau:

Tap chi Khoa hoc Trucmg Dai hfx Cdn Tha Phdn A' Khoa hoc Tti nhiin. Cong nghi vd Moi Irudng. 14 (2014): 11-44 Bing8:/<rCcacm6 hinh dn bio CFCDHR tir so li^u mo- hoa ciia Chen-Hsu

Mo hinh AIC Mo hinh AIC

AiUMAcH(0,2,l) ARIMACH(0,2,2) A R I M A C H ( 0 , 2 3 ) ARIMACH(1,2,0) AR1MACH(1,2,1) ARIMACH(1,2,2) ARJMACH( 1,2,3) ARIMAt^H(2,2,0)

221.7 221.9 220.76 229.53 223.67 225.5 222.75 229.53

AR1MACH(2,2,I) ARIMACH(2,2,2) ARIMACH(2,2,3) AR1MACH(3,2,0) ARIMACH(3,2,1) ARIMACH(3,2,2) ARIMACH(3,2,3)

223.9 221.49 222.76 229.57 222.51 222.14 221.72 So sdnh AIC ciia cac mo hinh tren ta diay mo

hinh ARIMACH(0,2,3) CO chi s6 AIC bing 220.76 la nho nhit.

i. Mo hinh chuoi thai gian md

Thuc hi^n theo 6 buac cua mo hinh chuSi thai gian mo ciia Abbasov-Mamedova nhu dd trinh bay trong 2.2.2 vdi dff lieu Bang 1, ta co bang tinh toan sau ciing nhu sau:

Bing 9: Ket qua n$i suy mo hinh chuoi thoi gian mo* Abbasov-Mamedova

Nam Binh lu thirc te Dinh Ifi npi suy 1998

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

255 384 490 447 442 347 402 390 370 356 320 352 377 427 398

371.64 245.77 384.87 489.82 440.83 437.52 338.69 399.98 385.18 364.83 351.08 314.17 349.07 373.83 424.60

AIC 28.08

Gid tri AIC tlieo mo hinh Abbasov-Mamedova nho ban so vai cdc mo hinh toi uu dd thiet ldp khi sir dung dH li^u g6c, drt lieu lam tron vd dii lifeu mo hoa.

5.4 D^ bio

Tir cdc mo hinh toi uu da lya chon trong 5.3a, 5.3b, 5.3c va 5.3d, tiln hanh du bao dinh lu tgi tram do Chau D6C din nam 2020, ta co bdng ting hop (Bdng 10).

Ta c6 nhitng nhdn xet sau ttr viec xay dung md hinh t6i iru va kit qua du bao dinh lii cua cac m6 hinh nay nhu sau:

- Chi so AIC cOa cac mo hinh toi uu xdy dung tu dir lieu ldm Iron, dG lieu ma h6a, chudi thdi gian ma nlio hon so vol mo hinh xay dung tir s6 li^u goc. Cu thi AIC tdng ddn theo thijr tir: Ch6i thoi gian mo (mo hinh Abbasov-Mamedova), dfl lieu lam tran, diJ liSu mo hda, dfl li^u g6c.

Kit qud du bdo dmh lu giai doan 2013 - 2014 tCr cdc mo hinh toi uu c6 su khdc biet. D6i vdi mo hinh chudi thai ^ian md va mo hinh chudi thdi gian xdy dung tit sd li«u md hda thi dinh lu cd chi^u di xudng. Hai rnd hmh chudi thdi gian dugc xdy dung tir sd lieu gdc va sd lieu lam Iron dy bdo"

dinh lu CO khuynh hudng tang nhung tdc dp tang khdng nhiSu.

Bang 10: Dir bio CFCDHR giai doan 2013 - 2020 theo cic mo hinh tk u Nim

2013 2014 2015 2016 2017 2018 2019 2020

ARIMA((IA2) ARIMAT-H(0.3.31 ARIMAr-„mj3) Chudi thMTiUn^ir 306? 5o7Ti '1 B 396.2

395.08 394.63 394.84 395.73 397.29 399.52 402.42

386.31 383.39 381.02 379.18 377.89 377.14 376.93 377.27

337.62 353.73 348.31 342.88 337.46 332.04 326.61 321.19

419.03 414.48 409.98 404.50 400.00 395.50 391.00 386.50

Tgp chiKhoa hgc TrudngDgi hgc Cdn Tho Phdn A: Khoa hgc Tu nhiin, Cdng nghi vd Mdi trudng- 34 (2014): 33-44

4 3 0 4 1 5 4 0 0

— 3 8 5

£ 3 7 0 355 340 325 310

-So lieu gdc - S d l i l u l a m tron - S 6 l i | u mdhoa -Chu6i thdi gian md

2013 2014 2015 2016 2017 2018 2019 2020 Hinh 4: Hinh ve du bio CFCDHR

6 KETLUi^N

M§c dCi, hi sd tuang quan cung nhu phd cua cic chu ky 5 nim, 11 nim vi 15 nam cao hon d cic chu k j khic nhung chdng cung khdng cd y nghia todng kl. Kit lu^n chu ky dinh lu sdng Hdu khdng cd chu ky phii hpp vdi thuc t l cdc nim qua.

Dya vao md hinh chu§i thdi gian md vd khdng md, vdi d& li^u goc, dft lieu lim uon, dtt lipu md hda, bii vilt da xiy dung md hinh tdi uu dinh lu s6ng H|u cho tCrng trudng hpp. Trong cac md hinh xay dyng, chl sd AIC cda md hinh chu6i todi gian md nhd nhit. Dy bio thiiy vdn ndi chung vd dy bdo dinh lu ndi rieng li bii todn phdc tg.p, sy chinh xac eiia cic mo hinh cin phdi cd thdi gian dl kilm chdng, tuy nhiin ket qud dy bdo tu cac phuong phap todng kl hi$n d^ii trong bdi viit cd toi dupe sd dung nhu mOt kinh toam khio quan trpng.

Cac md hiito vd cdch lam nliu da thyc hien cho dy bio dinh Iii sdng H§u Uong bii viit niy, cd tiii dupe thyc hi$n toeo cich tuong ty cho nhiiu dng dyng khic cda toye ti. ^^^^^

TAI Up] THAM ^^^^^'^^'^^^

1. A.M. Abbasov etal, 2002. Fuzzy relational model for knowledge processing and decision making. Advances in Matoematics.

I: 1991-223.

2. A.M. Abbasov and M.H. Mamedova, 2003.

Application of fiiz^ time series to population forecasting, Vienna University of Technology. 12: 545-552.

3. H.Bozdogan, 2000. Akaike's mformation criterion and recent developments in information complexity. Joumai of matoematical jjsycbology. 44:62-91.

giai doan 2013-2020 tu- cac md hinh tdi iru 4. K. Huamg, 2001. Huamg models of fiizzy

time series for forecasting. Fuzzy Sets and Systems. 123:369-386.

5. NguyenThanhSon, 2003. Tmh todn toiiy van. Nha xudt bdn Dai hpc Qudc gia Ha Ndi. H i Npi. 187 ti-ang.

6. Phan Van Tin, 2005. Cdc phucmg phap thdng ke Uong khi hiu. Nhi xuit bin Dai hpc Qudc gia Hd Npi. Hd N6i. 162 Uang.

7. Q. Song and B.S. Chisom, 1993. Forecasting eiuolknents wito fiizzy time series (Part I), Fuzzy Sets and Systems. 54: 1-9.

8. Q. Song and B.S. Chisom, 1994. Forecasting enrollments with fijzzy time series (Part II), Fuzzy Sets and Systems. 62: 1-8.

9. S.M.Chen, 1996. Forecasting enrollments based on fiizzy time series. Fuzzy Sets and Systems. 81:311-319.

10. S.M. Chen and C.C.Hsu, 2004. A New metood to forecast emollments using fuzzy time series. Intemational Journal of Applied Science and Engineering, 12:234-244.

11. S.R. Singh, 2008. A computational metood of forecasting based on fiizzy time series.

Matoematics and Computers in Simulation.

79: 539-554.

12. S.R. Smgh, 2009. A computational metood of forecasting based on high-order fiizzy time series. Expert Systems with Apphcations. 36:10551-10559.

13. Td Van Trudng, 2005. Phuang phap vd cdng n^be dy bdo lu Ddng bang sdng Cihi Long de tai cap nha nude, MS: MS:KT-08- 14. Phan vien khao sat qui hoach tody lpi.

112 ttang.