2022小美赛赛题的移动云盘下载地址 $ w. v# ~" _! l) I
https://caiyun.139.com/m/i?0F5CJAMhGgSJx ! A; N$ h$ a+ C, d" m9 }3 d$ `9 Y, k
2022 4 E( [* V" k6 c, N) Y6 z0 l/ DCertifificate Authority Cup International Mathematical Contest Modeling # I+ c/ j U; ^. Lhttp://mcm.tzmcm.cn. [0 {4 }* \4 Q$ N2 o% _
Problem A (MCM) 0 r2 c; w1 b7 y$ h- J, D* f* d( jHow Pterosaurs Fly1 O. u) N: n& n0 Y" g* x$ B
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They( h* x- H1 Q: U, y: p4 I
existed during most of the Mesozoic: from the Late Triassic to the end of " R3 F4 f K5 o4 P# Jthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved # x" l Z/ B! Q, Lpowered flflight. Their wings were formed by a membrane of skin, muscle, and1 p- P/ O: R9 _7 u8 N
other tissues stretching from the ankles to a dramatically lengthened fourth J% a$ }* h1 G7 i4 r1 }
fifinger[1]. # m$ ~! x" R) V- R) o# I7 K% Z: XThere were two major types of pterosaurs. Basal pterosaurs were smaller; \8 G) l, x# ^
animals with fully toothed jaws and long tails usually. Their wide wing mem0 H' a$ z9 f/ ]" N2 z" ~8 u6 [
branes probably included and connected the hind legs. On the ground, they " M+ u* _( D' V" z6 M4 ewould have had an awkward sprawling posture, but their joint anatomy and9 H& b9 ^! ~( {5 U: R- }
strong claws would have made them effffective climbers, and they may have lived. U0 j6 |1 k; j+ z
in trees. Basal pterosaurs were insectivores or predators of small vertebrates.% S( _6 B2 `2 ^
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.2 u4 v( ~' ]% t6 H3 E& v! Y
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails, 2 X; _% L; x! {" Z5 W Vand long necks with large heads. On the ground, pterodactyloids walked well on: N/ r9 r' S4 ~) [
all four limbs with an upright posture, standing plantigrade on the hind feet and, Z/ `' c4 }+ o
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil! d) d( | E; R8 R4 J7 e) U9 Q" r
trackways show at least some species were able to run and wade or swim[2]. ' N$ l" _" [& \! pPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which - s2 Y+ o0 y) h8 Z; \5 gcovered their bodies and parts of their wings[3]. In life, pterosaurs would have 7 u/ \* f, m0 p+ i7 thad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug 5 S6 T R" g6 z; v& V* b! Fgestions were that pterosaurs were largely cold-blooded gliding animals, de 1 t7 z( H5 }! r+ r. I$ ~" Rriving warmth from the environment like modern lizards, rather than burning 1 J& Q6 X& q% _) X. Q$ Ucalories. However, later studies have shown that they may be warm-blooded( \: D6 w$ R" a& y" j" c7 y
(endothermic), active animals. The respiratory system had effiffifficient unidirec ) X2 s8 T8 s5 K2 @, \: ~( stional “flflow-through” breathing using air sacs, which hollowed out their bones6 p- b# Z! f* I8 q
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from $ M7 C" p! d* T% y) Athe very small anurognathids to the largest known flflying creatures, including - `4 z: [5 S, G- L- t/ M3 k* Z1 I' s' }Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least5 a! ~8 i( p5 l
nine metres. The combination of endothermy, a good oxygen supply and strong 5 k# C! c0 ?+ y: b5 ^1muscles made pterosaurs powerful and capable flflyers. 1 n; W6 @9 @& _( HThe mechanics of pterosaur flflight are not completely understood or modeled 3 V9 w/ C) V/ D1 I, [1 c5 yat this time. Katsufumi Sato did calculations using modern birds and concluded& ^$ l: V" R5 C; \9 A/ n* E+ `
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,+ o. ^; [' i$ }! X w/ L
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able2 `/ z" `. G3 H: B
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].3 r4 _+ |" p8 _5 y! w2 z# q& e+ F! i0 I
However, both Sato and the authors of Posture, Locomotion, and Paleoecology5 {; d. k( x! b: t# |# J3 K) F* i
of Pterosaurs based their research on the now-outdated theories of pterosaurs - _; l8 n# m& E4 q/ ?being seabird-like, and the size limit does not apply to terrestrial pterosaurs, . m6 l+ K: S; a! @$ R3 g) rsuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that% G6 J& D, A" S3 ?7 R: }
atmospheric difffferences between the present and the Mesozoic were not needed5 l0 g- z) m) `4 L: Z: Z( \
for the giant size of pterosaurs[8].* @, Z: d1 s" Q- s
Another issue that has been diffiffifficult to understand is how they took offff. $ x3 Z% }+ I! t5 `3 `+ p; o, JIf pterosaurs were cold-blooded animals, it was unclear how the larger ones* q* E, Y* X" ` H
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage8 j) t$ ` R W. P7 I# B. M
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for + i6 b- K( x- E, {/ Cgetting airborne. Later research shows them instead as being warm-blooded % z' z2 x, w& t: i' F/ Wand having powerful flflight muscles, and using the flflight muscles for walking as* s5 A4 A" r/ `; V: i7 h) C8 N$ K
quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of5 H# q$ k9 J1 G \! a, I6 ^
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism ( n: U0 |$ O. n) M4 b1 }to obtain flflight[10]. The tremendous power of their winged forelimbs would / S) p6 A% _6 e; R4 q4 Wenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds9 Y7 u8 ]+ d7 _# c/ c2 D2 @
of up to 120 km/h and travel thousands of kilometres[10]. / J) |4 s% @! o3 k* EYour team are asked to develop a reasonable mathematical model of the # V. {( o5 C" q: Uflflight process of at least one large pterosaur based on fossil measurements and 4 } T6 X. y, H' U% c3 E) T$ mto answer the following questions.1 {0 b- m! I! l
1. For your selected pterosaur species, estimate its average speed during nor $ ^5 h- F1 k2 dmal flflight. * z3 U& n0 l# d" f% |( d2. For your selected pterosaur species, estimate its wing-flflap frequency during . k% m8 U; T6 Q* Q: F( enormal flflight.! p. z! N; f" O/ s% s: W
3. Study how large pterosaurs take offff; is it possible for them to take offff like' Z4 k m7 t" }9 `" ]
birds on flflat ground or on water? Explain the reasons quantitatively. * c! B2 g$ A) eReferences1 v3 l* }' `9 \5 Q; z7 Q
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight ! i5 h3 D* x V3 D+ x# fMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111. + l" t* j ^9 a+ ~/ U3 |2[2] Mark Witton. Terrestrial Locomotion. 4 W2 Q# }( F+ \; [https://pterosaur.net/terrestrial locomotion.php * ?+ t# { x1 }8 U- n[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs 5 {/ \* \1 ^9 ?, }$ ~( ~- SWere Covered in Fluffffy Feathers. https://www.livescience.com/64324-3 ]7 h; z2 @7 b0 ]. A
pterosaurs-had-feathers.html. B( g0 u- i! ?4 [2 Y7 n
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a 8 c4 [$ _: ?; P7 Y4 p6 S/ h Crare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)1 O( h2 O* ~- o
from China. Proceedings of the National Academy of Sciences. 105 (6): ?% Y6 Q+ H! j8 v8 i. e* M1983-87.9 _2 _/ K. R& V4 g' g! b. v
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust9 u; ]# H+ x# e, W- ^1 P
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):1 S6 G- }2 Q( }* Z3 ]+ u
180-84.' H7 P! a0 `2 \6 s0 c; ]( l
[6] Devin Powell. Were pterosaurs too big to flfly? % B3 o1 u2 j! R$ O& m$ ]) }https://www.newscientist.com/article/mg20026763-800-were-pterosaurs 5 H2 D( A4 @" X, Atoo-big-to-flfly/ 9 G% G" k9 | _: F+ u[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology8 }9 [) O: h2 l s/ f, _
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. 0 X2 \/ J# N# S8 C: e a+ o9 O[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable# J7 e, g# ?: [! U/ h* P. Z9 ]/ D
air sacs in their wings. ! h: |6 V% j: Q- ^* _) J; A% Nhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur# ]. \- J g/ I% K5 |: z! l
breathing-air-sacs 3 @- o w9 K' |, O; ?[9] Mark Witton. Why pterosaurs weren’t so scary after all.! k0 L/ O) H L
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils + d: R( S( ~0 }3 oresearch-mark-witton 5 J. H& U5 J/ B: m1 {, m6 m[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 3 Q. Q, C4 o/ ]" [/ p; u0 ^5 Shttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs ) n; _1 X, h& L0 Q* K$ bvault-aloft-like-vampire-bats/* v9 D" f3 C# B d; k7 _
8 r2 }- L) M$ p |# ^) L& }2022: t, Q( x: o9 D
Certifificate Authority Cup International Mathematical Contest Modeling' |: d, y! `3 [ \
http://mcm.tzmcm.cn / v# d# O3 m, P2 gProblem B (MCM) " Y' ^- M- O: b) Q3 m. jThe Genetic Process of Sequences 2 G) ^# s" q! y# y; ]4 V1 v# g1 BSequence homology is the biological homology between DNA, RNA, or protein( a" V7 R: M: X& G; \5 H! B
sequences, defifined in terms of shared ancestry in the evolutionary history of 1 Z9 r) Z% c5 x9 z4 [1 K {3 Ilife[1]. Homology among DNA, RNA, or proteins is typically inferred from their 7 D- x3 e5 ~2 a4 m- k9 J' knucleotide or amino acid sequence similarity. Signifificant similarity is strong ; M/ `! Z+ x0 ~evidence that two sequences are related by evolutionary changes from a common 4 ^/ J6 r3 d9 ]$ o- oancestral sequence[2]. 3 S$ G9 r, A- `; A% j1 v2 RConsider the genetic process of a RNA sequence, in which mutations in nu# t/ Y8 f. L8 s6 H. c
cleotide bases occur by chance. For simplicity, we assume the sequence mutation" |: K+ w1 [ E7 R
arise due to the presence of change (transition or transversion), insertion and6 G; w u- X7 \& v3 s9 \
deletion of a single base. So we can measure the distance of two sequences by8 t! E. }" G e% P7 }/ |3 |
the amount of mutation points. Multiple base sequences that are close together Z4 {7 q* p- [, X+ X: Q0 n
can form a family, and they are considered homologous.7 a% W/ B. }8 G) ?
Your team are asked to develop a reasonable mathematical model to com & Z, O9 |+ m7 i' S% Hplete the following problems. 9 I2 {. K' N7 f6 C& a. ^1 }9 c1. Please design an algorithm that quickly measures the distance between. n2 j& d, J# d# g3 d" q- L
two suffiffifficiently long(> 103 bases) base sequences.4 U9 M; y! \5 v3 E, n
2. Please evaluate the complexity and accuracy of the algorithm reliably, and 6 P" C9 B2 D1 k0 z qdesign suitable examples to illustrate it. & |, M! W( u7 r4 P+ T- Z0 Z" q' D3. If multiple base sequences in a family have evolved from a common an % R, o1 Y3 x5 H- G- icestral sequence, design an effiffifficient algorithm to determine the ancestral1 m' b. n: p F( R$ ~
sequence, and map the genealogical tree.2 { q& T; |0 P
References. Y4 c( P% a# N8 E
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re7 r2 z* ]- W, k; h" h6 l' |
view of Genetics. 39: 30938, 2005. / ^6 b& \" u% S( R/ y[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,4 n9 E* x h! {$ U. e+ p) z
et al. “Homology” in proteins and nucleic acids: a terminology muddle and 3 z3 t) J7 p. x' j Va way out of it. Cell. 50 (5): 667, 1987.: f% V8 D, l/ v, S% s i' C
/ Y8 J) {* A# |" u/ c( y7 }2022/ X% f1 O# z5 u8 v) u
Certifificate Authority Cup International Mathematical Contest Modeling . H6 P. u3 ?' ^5 c; Jhttp://mcm.tzmcm.cn 7 w) _+ h6 J! v$ qProblem C (ICM)( a6 D7 ~1 y$ F; g7 w# l% v5 v# G
Classify Human Activities & v& e# L H8 t. j( X5 C8 pOne important aspect of human behavior understanding is the recognition and9 ]8 ]- z4 @$ e3 j; T/ s4 a5 V1 B
monitoring of daily activities. A wearable activity recognition system can im9 A Z- c( c- u+ z
prove the quality of life in many critical areas, such as ambulatory monitor+ F# g) G' A0 S8 a$ j
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ ' y6 g. k! _" |2 x* Wity recognition systems are used in monitoring and observation of the elderly" W, Z5 X+ Y! N- F+ Z
remotely by personal alarm systems[1], detection and classifification of falls[2], 2 U! w' T8 }3 e2 P4 g7 bmedical diagnosis and treatment[3], monitoring children remotely at home or in - `" G( T } P9 Z' Pschool, rehabilitation and physical therapy , biomechanics research, ergonomics,% O" E- z- s7 }- [ y
sports science, ballet and dance, animation, fifilm making, TV, live entertain+ p( g( P4 i" _2 B
ment, virtual reality, and computer games[4]. We try to use miniature inertial - y7 l7 g8 C, Z' Z/ |sensors and magnetometers positioned on difffferent parts of the body to classify# m/ U. D5 B$ {0 {
human activities, the following data were obtained. 0 Q9 g* n/ F: W" `+ b1 }/ oEach of the 19 activities is performed by eight subjects (4 female, 4 male, ; O" A* ?6 ^- T$ F4 u, Qbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes. R: s- g& }4 W2 m: f. I) Q
for each activity of each subject. The subjects are asked to perform the activ 6 Z/ ~) m! p) t! wities in their own style and were not restricted on how the activities should be6 I$ c! F8 I& ^9 E: h, j3 n4 X
performed. For this reason, there are inter-subject variations in the speeds and / c, g O, a, {0 ?1 \& yamplitudes of some activities. 4 B" j6 ]3 s* ^. v8 i# ?; a b ]2 f1 z% ~Sensor units are calibrated to acquire data at 25 Hz sampling frequency. : m5 @- d' _$ s, v c# z; HThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal% h. x& c) C* K0 Y( o* {: }
segments are obtained for each activity. ( ~. q+ c) w2 zThe 19 activities are: & N' ~7 h+ b% b3 \+ v1. Sitting (A1); + Q% ?9 P9 Z, y8 j& z3 _5 Y3 h2. Standing (A2);( A( y$ f( Y0 R
3. Lying on back (A3);; g' M$ M$ R/ r
4. Lying on right side (A4); 4 P7 m: D* @7 [5. Ascending stairs (A5);: p9 F8 `7 Y1 p
16. Descending stairs (A6);( n7 o4 i2 R/ Q5 X. o
7. Standing in an elevator still (A7);, x( {) g, z, I; q7 _* m) R% x; R) e
8. Moving around in an elevator (A8); ) q' j+ _8 k: C& ~) V9. Walking in a parking lot (A9);' s5 x8 d7 T! m+ N3 ^2 ], ?+ n
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg % B5 k) p" h' e$ r: ^, Q! zinclined positions (A10); . u& }2 z$ |+ F11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions3 t" m2 d2 O3 q: u' q) Z+ L8 D/ d
(A11); 5 R! }! c. j5 A7 W- l I, ]12. Running on a treadmill with a speed of 8 km/h (A12);, a) ~) t {4 {
13. Exercising on a stepper (A13);/ g# G$ j: I' ? O/ [% h9 z
14. Exercising on a cross trainer (A14);6 @( n9 u$ B& l
15. Cycling on an exercise bike in horizontal position (A15);/ {5 y q5 v& I
16. Cycling on an exercise bike in vertical position (A16);. f" z( V; A" _! M" t
17. Rowing (A17); : Z! p0 f. s8 \% e18. Jumping (A18); ) a; n$ c; m1 X1 @* g8 m/ E/ |6 D, L19. Playing basketball (A19).( ]1 ?3 y/ {2 L* F: ?2 [4 h0 }9 |
Your team are asked to develop a reasonable mathematical model to solve * g/ ^4 x! e! z* n: D8 t" B. }0 h" vthe following problems. 8 m4 D4 [5 i7 i0 T# Z1. Please design a set of features and an effiffifficient algorithm in order to classify" `- y1 g8 C2 v2 W7 \' _0 [# @
the 19 types of human actions from the data of these body-worn sensors. 6 j, C) X8 s+ p& M2. Because of the high cost of the data, we need to make the model have . J) e7 I( b1 S# a& Da good generalization ability with a limited data set. We need to study! {, R! v# x& v5 j7 \0 ?
and evaluate this problem specififically. Please design a feasible method to ( m/ _7 F! |4 ^( g2 Tevaluate the generalization ability of your model.* W4 W( q+ B3 d
3. Please study and overcome the overfifitting problem so that your classififi-$ i# `2 V9 b; c0 Z/ A1 O8 M
cation algorithm can be widely used on the problem of people’s action6 ~ L+ a5 O' \8 }7 r' V1 J
classifification.4 Q) b" j1 U. w V2 V1 b
The complete data can be downloaded through the following link:' N$ Q, b; O3 ^& |7 ]$ {: M& J
https://caiyun.139.com/m/i?0F5CJUOrpy8oq 7 {" O3 f5 S& O7 z: y$ I2Appendix: File structure ; i7 N n9 [5 i9 x• 19 activities (a)6 G8 C6 Y+ E& V( `8 I( q7 ?! v, i
• 8 subjects (p)9 @2 ~: N/ S# |! c% V
• 60 segments (s)1 e4 l. x' P; ~( ~! J
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left , ]4 \9 M, _' _" H/ }leg (LL)" O" A, b3 `. o" B) D
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z ( M# [( P, E" y. a' |6 Nmagnetometers) ( Z$ l, b" L' [6 g; r7 o. y1 gFolders a01, a02, ..., a19 contain data recorded from the 19 activities. & K9 r0 x- x8 I* g5 R0 oFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the 1 O! q; s& [" U# a, a: p3 F! F8 subjects. / \& q- o: w; R1 t6 qIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each# f. f9 X4 E8 L5 d6 `9 j( W: \
segment.; }$ c- r/ S5 L
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 259 U7 i4 v1 a# J* S3 y; d4 W1 A
Hz = 125 rows.) T, X' z8 q$ W
Each column contains the 125 samples of data acquired from one of the7 o# l7 n" w6 y6 D+ P1 ?
sensors of one of the units over a period of 5 sec.- }) ?' Y: r: F
Each row contains data acquired from all of the 45 sensor axes at a particular , x+ `0 x' _/ C+ F+ ?5 d# m7 Dsampling instant separated by commas. / K; @/ `3 J, b& P1 S. _Columns 1-45 correspond to: $ w7 W+ p/ U9 w$ p- g3 w, j• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,7 z# l% o0 e* F' {
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,. H) F2 }% i7 R7 d! j# t# {
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, , y2 Q( \) T, D7 x• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,2 Y, q7 ]+ \6 v6 }1 c6 \+ [
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.6 r7 \" N# Y9 v
Therefore, - H3 B7 h/ |9 `- R9 `2 C• columns 1-9 correspond to the sensors in unit 1 (T), 9 k. H$ n) v$ {/ q s/ D s% ^• columns 10-18 correspond to the sensors in unit 2 (RA), " c; E$ m; _. W% R7 ^, S/ m" j• columns 19-27 correspond to the sensors in unit 3 (LA), : b3 H+ Y& [5 n% \" K• columns 28-36 correspond to the sensors in unit 4 (RL),- Y' U0 f& b+ o7 e5 \- c5 v
• columns 37-45 correspond to the sensors in unit 5 (LL). ; f2 F2 m" l6 P3References+ E l( k4 e [6 m/ Y
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic 6 ]. j9 q" q" ~; w* |( ydaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. & B" s8 q9 V7 c* x8 V; N+ B* F' G42(5), 679-687, 2004; M, A0 B: @) }4 Y9 \& T
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of 7 i" @- l- M+ D f. T9 J( v) E6 xlow-complexity fall detection algorithms for body attached accelerometers. $ N/ q: N& e) m7 C, x: ?6 |3 DGait Posture 28(2), 285-291, 20089 N9 n; @1 g! _
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag * g" \" Q2 A6 Y/ ^/ J" [: m Qnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.: y/ x+ _8 d- u# r! o: y
B. 11(5), 553-562, 2007 % E5 D% K+ s: N% u[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con/ ~. o5 W( I! _$ L8 J$ }) y% i
trol of a physically simulated character. ACM T. Graphic. 27(5), 20086 V) d! P2 h' h) k- ~
8 E' |3 v/ ~+ W1 N0 n# T8 ^# k2022 4 x! U& M. S- H2 Z7 L1 vCertifificate Authority Cup International Mathematical Contest Modeling9 H4 R0 ~% L1 T& B# i, O
http://mcm.tzmcm.cn ' u9 d8 b. ], u# ?9 I* pProblem D (ICM)5 y& u0 ^% I; j0 v
Whether Wildlife Trade Should Be Banned for a Long 2 D; q4 L) x( K XTime j9 I$ \" T6 @Wild-animal markets are the suspected origin of the current outbreak and the ; B! U: C* ~; a& _2002 SARS outbreak, And eating wild meat is thought to have been a source1 _& o8 r- V; n* g
of the Ebola virus in Africa. Chinas top law-making body has permanently& U. Q: O: G: x7 i
tightened rules on trading wildlife in the wake of the coronavirus outbreak, 4 H2 K/ |+ v) i7 d, `3 G% ewhich is thought to have originated in a wild-animal market in Wuhan. Some4 i% i1 K3 W' q5 v, l
scientists speculate that the emergency measure will be lifted once the outbreak# D1 t7 g+ s; O
ends. 7 j$ P* k0 b( z0 wHow the trade in wildlife products should be regulated in the long term?! F( q. D( v" Q7 ^: r! t1 w
Some researchers want a total ban on wildlife trade, without exceptions, whereas / E; O/ i- f& H3 X4 }4 K4 Zothers say sustainable trade of some animals is possible and benefificial for peo . X/ q4 |( {7 {& nple who rely on it for their livelihoods. Banning wild meat consumption could : u- d( {; `" E+ i0 @9 rcost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil, ^& A' d( ^5 {$ B7 N9 ?
lion people out of a job, according to estimates from the non-profifit Society of 7 L/ J1 g) S& c! r4 @% nEntrepreneurs and Ecology in Beijing./ z* N, q) K2 V! ]& r0 y2 W, L
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology / }5 h5 P5 [/ B) s; b2 S7 jin China, chasing the origin of the deadly SARS virus, have fifinally found their! ?. q, U4 u* ^: V: K1 k
smoking gun in 2017. In a remote cave in Yunnan province, virologists have2 E) L* Z: r+ H) v- i
identifified a single population of horseshoe bats that harbours virus strains with . D, ^/ q: M0 C/ qall the genetic building blocks of the one that jumped to humans in 2002, killing9 T `) G2 x; V8 {2 N
almost 800 people around the world. The killer strain could easily have arisen 3 N: l" Z2 J" Q" vfrom such a bat population, the researchers report in PLoS Pathogens on 306 N" l6 l( m0 u7 b: P! S0 U, p
November, 2017. Another outstanding question is how a virus from bats in : a6 Q& k5 @: ZYunnan could travel to animals and humans around 1,000 kilometres away in 0 C, r: H# L4 LGuangdong, without causing any suspected cases in Yunnan itself. Wildlife " P6 K% a$ P' J6 Z$ s- ytrade is the answer. Although wild animals are cooked at high temperature t# k2 S- l) Swhen eating, some viruses are diffiffifficult to survive, humans may come into contact3 X( g3 ?+ ]. b: K z. ]
with animal secretions in the wildlife market. They warn that the ingredients) }0 ~2 m7 ~% o
are in place for a similar disease to emerge again. / `2 Y9 u! d3 q3 j4 g; _Wildlife trade has many negative effffects, with the most important ones being:# m. y7 x% p+ Y: U H+ j
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS 2 v9 G' @ I) ]8 u! r; X/ P9 Q% ~outbreak in 2002.Credit: Matthew Maran/NPL( n! e! Q# s6 d* V2 F
• Decline and extinction of populations " p7 z# N, q5 P• Introduction of invasive species ! \& q2 |& _+ a9 G) j• Spread of new diseases to humans 2 h* F: |9 @; e7 P- ^% [; }" fWe use the CITES trade database as source for my data. This database : V& m, A, S" A6 @contains more than 20 million records of trade and is openly accessible. The$ U' ~) v& t/ J% a; `0 y. M/ d4 c
appendix is the data on mammal trade from 1990 to 2021, and the complete , F* d* Z Y7 A; qdatabase can also be obtained through the following link:$ W: z% `* S, m7 E6 W/ o) n
https://caiyun.139.com/m/i?0F5CKACoDDpEJ 7 j. H8 D/ G8 |4 e) X" tRequirements Your team are asked to build reasonable mathematical mod 7 S: J1 l0 o/ o4 A" K/ A" Lels, analyze the data, and solve the following problems:) L# }# } L w& {4 s# i" J8 ?, l2 m
1. Which wildlife groups and species are traded the most (in terms of live9 u9 H8 F& H- p) K0 N" Y) a! m1 G, w
animals taken from the wild)? 3 o9 _% |" y( s' Q- k, v2. What are the main purposes for trade of these animals?8 p" ~) g$ Y+ |
3. How has the trade changed over the past two decades (2003-2022)? ) c5 \; r$ f. {& _4. Whether the wildlife trade is related to the epidemic situation of major 5 u0 g; Q* E6 E8 |/ P5 y/ dinfectious diseases?0 J, P1 O: \( }) [8 _) d; I* d
25. Do you agree with banning on wildlife trade for a long time? Whether it 8 f" r2 t, e& z5 l) Swill have a great impact on the economy and society, and why? 0 `9 E; V4 b9 A6 C6. Write a letter to the relevant departments of the US government to explain 5 O! ]$ S3 e6 |0 \your views and policy suggestions. . ~1 p* \5 h# b/ @: X6 y5 d- b( R$ g7 c( s7 Z% x
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' Y; P% G s; g1 w @+ F # G- s5 s4 p2 H& r. Z! \: s( c 7 B, E; V$ Z9 I" _8 B/ O6 B/ u! M7 U0 t+ l# q