2022小美赛赛题的移动云盘下载地址 9 H+ E9 k A! @: N9 [2 b5 X- b# H% chttps://caiyun.139.com/m/i?0F5CJAMhGgSJx $ m3 V' R- E7 b+ l1 h! ~" F% {; O, [. _3 F X
2022% f3 c' d/ X- T4 a6 v# z
Certifificate Authority Cup International Mathematical Contest Modeling u& f! ?. L: h _+ p& Ahttp://mcm.tzmcm.cn # C6 W" H# f: C5 Q" w) r _7 GProblem A (MCM) 4 B, J8 B' R. Z* t8 E1 x& F/ h7 sHow Pterosaurs Fly - O0 B* a0 B! u: h$ Y0 n* }Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They . w3 A L8 v5 Oexisted during most of the Mesozoic: from the Late Triassic to the end of9 Z# c$ M6 Q2 B: ~3 ]5 ]
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved K- \( [3 v3 w, c
powered flflight. Their wings were formed by a membrane of skin, muscle, and# F j! ^ v3 `( J8 `7 _
other tissues stretching from the ankles to a dramatically lengthened fourth' A% J( I$ S; z0 n" d, ]
fifinger[1].+ }8 S9 ]3 _' e4 \4 g4 v9 u, }# J6 G/ @
There were two major types of pterosaurs. Basal pterosaurs were smaller3 X k& y: O: ~% |
animals with fully toothed jaws and long tails usually. Their wide wing mem # O# U1 C% {" Q: Rbranes probably included and connected the hind legs. On the ground, they 7 ?2 \ _4 j& Y8 j, r/ Zwould have had an awkward sprawling posture, but their joint anatomy and : M! I) ^4 e) R( d6 Kstrong claws would have made them effffective climbers, and they may have lived. q3 y; x* S& k% v e1 |
in trees. Basal pterosaurs were insectivores or predators of small vertebrates. 8 x [ X6 n# e8 v2 jLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. 8 I0 O( Y R6 S$ m; W$ c8 [Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,; X; V$ I: z( ~
and long necks with large heads. On the ground, pterodactyloids walked well on ) `/ Q! C( S7 s5 i; O1 W. G8 H/ Nall four limbs with an upright posture, standing plantigrade on the hind feet and2 I$ q* Z, J+ Z. r" L9 M# |
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil+ N7 D- b$ l% S1 E0 M* f1 I
trackways show at least some species were able to run and wade or swim[2].' y, c0 E: _, E3 P# q
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which 6 g1 a$ s" Y5 L3 u$ a N* dcovered their bodies and parts of their wings[3]. In life, pterosaurs would have 2 O" R6 z" S- y5 g1 O0 ]had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug % W( ^, Y- D3 x9 rgestions were that pterosaurs were largely cold-blooded gliding animals, de" ~' w4 Y9 z# k( A
riving warmth from the environment like modern lizards, rather than burning8 ~2 f; M; w+ B, y/ s5 n
calories. However, later studies have shown that they may be warm-blooded1 C+ ?# J7 l& @ |; o9 O5 V
(endothermic), active animals. The respiratory system had effiffifficient unidirec 3 L. @9 J/ F" O9 jtional “flflow-through” breathing using air sacs, which hollowed out their bones! x1 V2 M$ R$ i5 R( h0 @
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from # X0 X6 m7 R K* y8 u: Uthe very small anurognathids to the largest known flflying creatures, including , q3 a, @" P6 |: U2 R* wQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least& z+ Y, }* `( t% Y
nine metres. The combination of endothermy, a good oxygen supply and strong / p, u" K8 S/ A1muscles made pterosaurs powerful and capable flflyers.) u+ A5 z$ \+ q
The mechanics of pterosaur flflight are not completely understood or modeled % B0 L% A/ \9 P& s3 u# Fat this time. Katsufumi Sato did calculations using modern birds and concluded / F# t; v& v# Wthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture,# o$ O4 x: a& H& R% _! X
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able : S" Q! x& I; e( [3 g3 ato flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].$ e3 _* g! c1 _9 x6 r- X/ [$ d
However, both Sato and the authors of Posture, Locomotion, and Paleoecology* d* b: L% ^9 x8 l- m, g
of Pterosaurs based their research on the now-outdated theories of pterosaurs6 g: d1 S; b7 {( ?$ A* H
being seabird-like, and the size limit does not apply to terrestrial pterosaurs, - [( |' ~8 i- N3 X- ~) p* Hsuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that . e9 Y' @ V7 |atmospheric difffferences between the present and the Mesozoic were not needed! @9 O/ W5 G! Y8 a5 y& B$ S
for the giant size of pterosaurs[8].$ ]. J$ _* |# [; n3 \9 z# @! m
Another issue that has been diffiffifficult to understand is how they took offff.; j9 @ @% Z# E$ r/ [5 B. Z
If pterosaurs were cold-blooded animals, it was unclear how the larger ones 7 W, L0 P- s- e c5 s4 X9 Mof enormous size, with an ineffiffifficient cold-blooded metabolism, could manage 0 a. z0 Q5 F8 V$ P H( a2 s5 Ea bird-like takeoffff strategy, using only the hind limbs to generate thrust for3 u9 G/ |# L$ h$ |6 h% z) Y$ b
getting airborne. Later research shows them instead as being warm-blooded9 j) u( q" h5 }% X4 l
and having powerful flflight muscles, and using the flflight muscles for walking as ' i# X$ V- F( o; z; A1 k$ |quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of ! k# C2 Z% r# c/ a4 r, U8 _Johns Hopkins University suggested that pterosaurs used a vaulting mechanism # n) n5 c% |0 U1 \3 Y9 G8 cto obtain flflight[10]. The tremendous power of their winged forelimbs would0 ~' v7 ^3 M i* u
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds 6 |4 ?8 c* c5 Xof up to 120 km/h and travel thousands of kilometres[10].) O! K! M6 [0 B8 G. g d
Your team are asked to develop a reasonable mathematical model of the 1 \' k( d6 Q: o$ dflflight process of at least one large pterosaur based on fossil measurements and : D$ x g& L; j; |0 f/ bto answer the following questions./ `+ F# i, o* r) o+ {
1. For your selected pterosaur species, estimate its average speed during nor9 u& ^' I6 N8 X& B7 d( H
mal flflight. ; T% |% ?& D' a T+ F2 A! d2. For your selected pterosaur species, estimate its wing-flflap frequency during! u/ h0 ?9 y$ I+ o; m
normal flflight. ' B: B, c4 [& Q% n$ f$ a4 Y3. Study how large pterosaurs take offff; is it possible for them to take offff like) D) g# W O) G
birds on flflat ground or on water? Explain the reasons quantitatively. 9 j7 Z5 _# z: n& e, q: JReferences 9 E; ?! Z! E$ p: u[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight ) v" ~/ {! L; w: [# K+ @8 \1 M3 SMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111.1 c& Q r2 B6 ?- ?5 ~8 j2 m2 n; c
2[2] Mark Witton. Terrestrial Locomotion. 4 j2 {, C1 c7 H2 `, H q# P3 Khttps://pterosaur.net/terrestrial locomotion.php 7 \6 e0 y# q; j4 k* Z1 `6 Y[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs! A5 j8 X2 I# K. O$ i
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324-2 G/ q; U( [1 M5 I' v3 C8 A
pterosaurs-had-feathers.html% T/ E1 i/ d2 h, |
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a' o) s5 I5 a: u4 M6 D
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) / X/ N Y" L5 d+ i6 J- ifrom China. Proceedings of the National Academy of Sciences. 105 (6):. O f* P7 j0 y, D- P
1983-87./ `& ^" @ p' V4 Y- A4 h
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust2 f2 V0 a) t* H9 Y: B* N" M9 q* ], d
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4): + i8 l) R) }; g180-84. " R# r% X i, r4 n( ^" N! ?9 E[6] Devin Powell. Were pterosaurs too big to flfly? 8 H, h6 l: D, l8 l: Fhttps://www.newscientist.com/article/mg20026763-800-were-pterosaurs! s* D# h4 _% B% m
too-big-to-flfly/" q" y- e; C& g" d. ~ y
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology ' {( C$ ]1 V0 F! a7 i R, cof pterosaurs. Boulder, Colo: Geological Society of America. p. 60.& e$ D- W) W+ k2 R' s |
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable/ C, Z, k+ W& {3 F# c
air sacs in their wings. * S8 G7 I( Z) s# e3 bhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur : V) W6 i: L1 c2 `2 r) Y- {! ~+ i6 {breathing-air-sacs ' @( }( l& l2 F[9] Mark Witton. Why pterosaurs weren’t so scary after all.& |' m) j5 ]8 f- h8 b* R0 q
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils' j0 U; W, p% B
research-mark-witton- p5 S, j' f9 U
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?+ r! t( X2 X; x
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs 4 x+ }2 O# [$ G2 u; m9 L' x4 d" ]vault-aloft-like-vampire-bats/6 I2 }5 K O$ O6 s) s9 n
) P$ s3 S+ ~5 ]2022 $ e% X9 m" ~% }: \/ iCertifificate Authority Cup International Mathematical Contest Modeling - f s9 L$ S/ C& r; khttp://mcm.tzmcm.cn Z1 Z* s1 ~9 n vProblem B (MCM): D1 x2 y4 J4 m2 R$ O3 v& P
The Genetic Process of Sequences 4 i3 K& w$ r O& j$ W8 `Sequence homology is the biological homology between DNA, RNA, or protein 3 X J$ [3 E! |' d4 t+ c4 |7 i8 W _sequences, defifined in terms of shared ancestry in the evolutionary history of 7 ^5 A+ `# E9 x7 P+ N3 D; u# olife[1]. Homology among DNA, RNA, or proteins is typically inferred from their3 E" D* _8 Y9 B3 e' q4 t* {
nucleotide or amino acid sequence similarity. Signifificant similarity is strong5 y7 w% R r1 U. _, F: V3 i- \2 P$ y u; T
evidence that two sequences are related by evolutionary changes from a common3 X3 ]9 F0 u8 u: F x1 f
ancestral sequence[2]. # H0 k9 ]4 |& j& u5 [Consider the genetic process of a RNA sequence, in which mutations in nu K4 q7 L( m: |$ o$ Y& D9 x
cleotide bases occur by chance. For simplicity, we assume the sequence mutation1 S4 N" h: Q: V4 F) I
arise due to the presence of change (transition or transversion), insertion and' L# n, [3 g5 S+ A9 i+ H" B/ }
deletion of a single base. So we can measure the distance of two sequences by0 J( y# V% R- \+ u3 @- ^! B
the amount of mutation points. Multiple base sequences that are close together / i* V8 ~4 N3 N N! D2 r& zcan form a family, and they are considered homologous. + S* t& @8 O5 Y2 [, K' IYour team are asked to develop a reasonable mathematical model to com ! w; Z# t% L" N1 B D% Yplete the following problems. % z- F2 @; K" [. T c3 S1. Please design an algorithm that quickly measures the distance between 1 n) @) v- n( I9 @' B# }9 m2 E) ytwo suffiffifficiently long(> 103 bases) base sequences. # Z; L0 @6 t$ k" Q2. Please evaluate the complexity and accuracy of the algorithm reliably, and/ M1 T& C! J$ d( B0 n
design suitable examples to illustrate it. ( d* ~( {- {; R3. If multiple base sequences in a family have evolved from a common an( H( z% v7 n) o' I5 ^
cestral sequence, design an effiffifficient algorithm to determine the ancestral2 X+ S l) o6 o ~9 t0 T8 `# B
sequence, and map the genealogical tree.3 q3 D: m; ~2 G3 Z* |- Q
References ' C4 Q. @# @9 C! w6 A[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re . E: Z5 d1 Z+ s8 I9 Pview of Genetics. 39: 30938, 2005. 3 G! P& t* D8 A2 G- B. H! t[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, 5 C! f, a- Q- o4 P5 Uet al. “Homology” in proteins and nucleic acids: a terminology muddle and: ^% W5 Z: ^# E a& P
a way out of it. Cell. 50 (5): 667, 1987. * H' h/ i0 j7 {; l$ k8 c& {4 g% Y6 c" n9 J- X
2022 & e4 g# r) P( Z b7 O- l* C5 PCertifificate Authority Cup International Mathematical Contest Modeling 8 h- Y4 C' S& U9 qhttp://mcm.tzmcm.cn- ?$ h7 f$ j/ X* G; c% s
Problem C (ICM) - U2 C9 B+ D$ mClassify Human Activities $ t$ q' u2 \6 U& z+ o. YOne important aspect of human behavior understanding is the recognition and ( H6 {2 q7 |9 \* X1 gmonitoring of daily activities. A wearable activity recognition system can im * E' {7 {- p/ K0 Oprove the quality of life in many critical areas, such as ambulatory monitor; F! A7 v0 K* w+ H4 Z
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ ) T" J. K* e, r- Z2 oity recognition systems are used in monitoring and observation of the elderly/ F1 f' r( z/ y* C
remotely by personal alarm systems[1], detection and classifification of falls[2],* R6 g- w' F" m! u( {
medical diagnosis and treatment[3], monitoring children remotely at home or in , n1 y- {5 {2 G: Hschool, rehabilitation and physical therapy , biomechanics research, ergonomics, " e" l+ d" o3 i- M* H- C0 G; @8 w' Fsports science, ballet and dance, animation, fifilm making, TV, live entertain / i5 Y4 m4 s7 K; r: vment, virtual reality, and computer games[4]. We try to use miniature inertial ( Q# D) ?% A, ^4 e7 m% N( D: i+ \sensors and magnetometers positioned on difffferent parts of the body to classify1 [% }; B9 R0 }1 p
human activities, the following data were obtained.: D3 B; H/ }1 _1 t) t% V/ r5 j! N
Each of the 19 activities is performed by eight subjects (4 female, 4 male, `: S& `' ]4 p
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes7 f' `# p1 S( [* T7 U" y
for each activity of each subject. The subjects are asked to perform the activ, u0 G' z6 L3 Z5 E& Y
ities in their own style and were not restricted on how the activities should be 8 F5 k) [& n$ n" p, D+ t( ^performed. For this reason, there are inter-subject variations in the speeds and / T" D1 I. S0 p# C, Tamplitudes of some activities. + z+ W& f# w) i5 n: zSensor units are calibrated to acquire data at 25 Hz sampling frequency. $ f" e! x, u; O- ^The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal$ Q q4 s0 Z3 E8 E$ N3 [
segments are obtained for each activity. ' `# C2 p+ c6 O- s7 iThe 19 activities are:4 m) L M" j5 u" N
1. Sitting (A1); 8 i! x! j2 v1 U4 O0 }2. Standing (A2); + W5 `5 |- B) F0 a, q1 v4 I3. Lying on back (A3);* n. t$ z/ d' G. N" r! h2 Z' t
4. Lying on right side (A4);7 x0 \% L: ^* h: S5 @' Q, I0 l
5. Ascending stairs (A5); & g4 x# u [ D+ F R& e7 j16. Descending stairs (A6);! H6 T; w; P" k* P2 t8 U2 ^
7. Standing in an elevator still (A7); 6 _$ M$ f6 D: R& l( ~5 B. [) ]8. Moving around in an elevator (A8); 2 k9 I3 @+ d+ i9. Walking in a parking lot (A9);: e. @8 P' U. _% ^
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg: L) h$ h; l1 u
inclined positions (A10);4 ~" j! g+ v2 V& W2 e, g2 b
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions 6 Q9 Q! T- K' W1 E) y8 |7 o* X+ O(A11);, A- [7 ]7 f& G- \0 s
12. Running on a treadmill with a speed of 8 km/h (A12);, J5 _2 j4 u5 B7 o# Z- ]2 f5 S
13. Exercising on a stepper (A13);6 U( _9 N# C/ w' A0 q% e3 P
14. Exercising on a cross trainer (A14); - D d# c* c; D& v& c1 P15. Cycling on an exercise bike in horizontal position (A15); , J) y4 R- D2 F8 w9 d16. Cycling on an exercise bike in vertical position (A16); ! B/ p- m4 |7 J* e. k. {7 S+ k. v17. Rowing (A17);- W( u+ K9 W1 N- K6 j( L
18. Jumping (A18);: v8 b- W1 V6 t5 w/ u% Y' d- O
19. Playing basketball (A19). + w3 Y: Z3 F4 B1 F n: ?$ ?Your team are asked to develop a reasonable mathematical model to solve: k8 f, l3 C2 r8 p/ E% n
the following problems. 1 U) E) h3 c8 `7 ^ q1. Please design a set of features and an effiffifficient algorithm in order to classify2 [- W" z& ?/ p% m% L
the 19 types of human actions from the data of these body-worn sensors." ]9 `$ a2 E. Y$ r3 q: P9 r
2. Because of the high cost of the data, we need to make the model have 5 P% f# R* B- _a good generalization ability with a limited data set. We need to study# r6 R1 {3 `8 D# V6 {6 F7 ?7 u
and evaluate this problem specififically. Please design a feasible method to 6 z+ v/ n, D1 B! o2 I6 k I jevaluate the generalization ability of your model. " L$ s( F' k$ b, G3. Please study and overcome the overfifitting problem so that your classififi- 3 W; ]# Y/ x' z; M3 @2 }cation algorithm can be widely used on the problem of people’s action$ \7 P) g+ E" I2 Q6 V
classifification. # e; ^7 j0 U4 w+ ~- o, N% f- eThe complete data can be downloaded through the following link: . Z S- Z. c1 Nhttps://caiyun.139.com/m/i?0F5CJUOrpy8oq ! t! m% M5 I; b2Appendix: File structure9 t' D# l+ C# L6 B" V
• 19 activities (a); ~& u# T8 T9 R q+ I- `, A
• 8 subjects (p)8 `# u2 _0 [9 _+ y) e
• 60 segments (s)5 ~4 x2 E( h- Z0 v1 A6 [
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left8 ^, e5 B+ Y% H& s: l8 A* M
leg (LL)8 v7 Z, ?. N6 Q& d, Z
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z 2 E$ I8 T7 V1 q. Q3 cmagnetometers) ( K& A" G! R5 Y% {/ F& @: P; IFolders a01, a02, ..., a19 contain data recorded from the 19 activities." r4 J7 T4 r$ h% S
For each activity, the subfolders p1, p2, ..., p8 contain data from each of the' Z$ t7 G7 R2 v- P
8 subjects.# ?4 M- |' g" P
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each 7 p& M& O6 A1 U6 c+ p0 Wsegment. % h$ P7 C6 e% m; bIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25, Z1 n7 u N2 d- O# B9 @
Hz = 125 rows. O$ I# n0 }" l% b8 \8 b: LEach column contains the 125 samples of data acquired from one of the; x; v( J+ t; l! H( |/ M2 x, M
sensors of one of the units over a period of 5 sec. 2 s6 e) e. l( E3 ~" n' [9 AEach row contains data acquired from all of the 45 sensor axes at a particular) ^6 y( d4 h& F1 N/ y* @! T
sampling instant separated by commas.! E5 f7 ^* |6 u/ m' G3 e
Columns 1-45 correspond to: 0 E- T' e5 x: h+ A: V• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, 1 q6 A: f2 ^, M$ z& ?- K- k' ~• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,5 ?+ P+ N, j: o/ y1 }
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag,# f; H3 I# S" |8 @0 L
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, & G) B; I; p+ y$ A' t• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. ( _. F2 D& } i; X( ATherefore,) F2 s5 Y: L. k
• columns 1-9 correspond to the sensors in unit 1 (T),; P8 J3 U1 O8 y6 X/ Y2 U: l/ k
• columns 10-18 correspond to the sensors in unit 2 (RA), & F3 S, Z+ C6 h6 Q: l' W* v• columns 19-27 correspond to the sensors in unit 3 (LA),0 e1 S x! H2 R* L( Q
• columns 28-36 correspond to the sensors in unit 4 (RL), 1 u; A0 e4 \8 ]9 R/ ?2 i• columns 37-45 correspond to the sensors in unit 5 (LL). : [: `9 |& f+ j4 a3References+ B+ w! s! N/ ?) ], J
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic& r% g/ }2 O4 S- }$ `
daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. ) j* F1 {% Z- s+ L42(5), 679-687, 2004" a/ m3 E. `( t
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of7 J% M: v n, {& U" L1 P( I
low-complexity fall detection algorithms for body attached accelerometers. $ M* O9 m. w& tGait Posture 28(2), 285-291, 2008 2 b* `% k% s) a2 q[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag$ A( ^3 l" ~+ ^7 r- n3 s
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. ' L1 r' ^$ w0 h0 B! ~+ WB. 11(5), 553-562, 2007/ f9 I. q* [4 [4 w# g; l
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con6 Q% L( {$ \: O
trol of a physically simulated character. ACM T. Graphic. 27(5), 2008 - g7 G# K( p9 s$ N$ k0 U( i # F/ b% a7 v, ^$ G2022 * }0 {! y/ d }: U( t* MCertifificate Authority Cup International Mathematical Contest Modeling 5 M1 I" s4 n( ^ Zhttp://mcm.tzmcm.cn & k2 Y& {: L' m R3 wProblem D (ICM) / A# W7 R+ W- v+ N2 y* ]! yWhether Wildlife Trade Should Be Banned for a Long 7 O \- }" _5 s+ z- ^9 eTime 8 T9 \ M* q) K+ }! uWild-animal markets are the suspected origin of the current outbreak and the " p5 h: S; |. S' g1 u6 G0 P: K. Y2002 SARS outbreak, And eating wild meat is thought to have been a source* M8 r( m- g4 v$ R/ C
of the Ebola virus in Africa. Chinas top law-making body has permanently. U ?! K4 C& U& i
tightened rules on trading wildlife in the wake of the coronavirus outbreak, : K. _ V8 \8 k' G, _which is thought to have originated in a wild-animal market in Wuhan. Some* Q6 Z- n7 J3 H* X% D+ ?% f
scientists speculate that the emergency measure will be lifted once the outbreak 9 r& U" C- n$ X- P3 Z( Yends. 7 d$ P# X4 v" D4 e# j2 jHow the trade in wildlife products should be regulated in the long term?9 L9 Q& N H) U$ k1 @
Some researchers want a total ban on wildlife trade, without exceptions, whereas/ I3 p$ M" O. P5 o1 f8 Q
others say sustainable trade of some animals is possible and benefificial for peo. C) C6 D' d5 |8 |0 r/ G9 V; x/ {; J
ple who rely on it for their livelihoods. Banning wild meat consumption could% k$ \2 v! l* c$ U7 m% s2 G3 W
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil * L9 p2 Z B# |1 olion people out of a job, according to estimates from the non-profifit Society of 0 r1 r: S# b2 B; g1 Y5 XEntrepreneurs and Ecology in Beijing.& _7 t1 R; F* }9 j/ G9 u, r. d
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology - L9 a$ L" d c9 |# ~in China, chasing the origin of the deadly SARS virus, have fifinally found their7 b" H& c% O( e- }& M2 \7 F1 h
smoking gun in 2017. In a remote cave in Yunnan province, virologists have + r: a! { I* r( s2 i% P d' }identifified a single population of horseshoe bats that harbours virus strains with3 h4 X& `& L+ w* ^: N/ |2 ]
all the genetic building blocks of the one that jumped to humans in 2002, killing / n( R1 W1 t& r' B& k3 W% z- V- aalmost 800 people around the world. The killer strain could easily have arisen% z! j7 l+ W4 c
from such a bat population, the researchers report in PLoS Pathogens on 30& u8 A6 J! t R3 O! n- B
November, 2017. Another outstanding question is how a virus from bats in 8 Z3 S5 x1 O" eYunnan could travel to animals and humans around 1,000 kilometres away in* B& U, r3 w% S9 f
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife- f \/ m6 s* m6 W* u
trade is the answer. Although wild animals are cooked at high temperature# P- z& F/ |) V w
when eating, some viruses are diffiffifficult to survive, humans may come into contact! ^3 y" f3 G- J% K! H
with animal secretions in the wildlife market. They warn that the ingredients- l' I! t, \9 ?! m: p
are in place for a similar disease to emerge again./ N7 N6 o* k5 k. z
Wildlife trade has many negative effffects, with the most important ones being:/ Y; S$ d6 w6 }. U+ q- A
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS5 D k, `0 F, j' b" u
outbreak in 2002.Credit: Matthew Maran/NPL ! g+ \0 [2 a$ g& N+ G• Decline and extinction of populations * n9 k9 V/ R, w• Introduction of invasive species+ e9 o+ e4 T2 y
• Spread of new diseases to humans ) l" f2 Z; l5 c7 h' I, lWe use the CITES trade database as source for my data. This database * |/ C1 V: H8 b. P( Y+ L, N( Scontains more than 20 million records of trade and is openly accessible. The: [ U3 V K; t5 w7 S9 M! }. H8 y$ _
appendix is the data on mammal trade from 1990 to 2021, and the complete % G1 N) O% S5 o7 Z: ?6 fdatabase can also be obtained through the following link:. E2 M& ~2 k f% _: {9 r
https://caiyun.139.com/m/i?0F5CKACoDDpEJ3 D6 }4 y) B2 h/ `9 }$ }
Requirements Your team are asked to build reasonable mathematical mod! c4 ?! h1 d5 d7 J. K# A* }
els, analyze the data, and solve the following problems: ! L9 I$ S ~. q+ s6 J1. Which wildlife groups and species are traded the most (in terms of live4 q `5 x7 E! V! \$ E. A
animals taken from the wild)? 4 N2 q' Y. w8 K" `" }; T2. What are the main purposes for trade of these animals?6 b/ O* }( v1 F) |* Z$ D4 \
3. How has the trade changed over the past two decades (2003-2022)?2 ^/ c6 d* i* T, K" L6 D1 |
4. Whether the wildlife trade is related to the epidemic situation of major" P( F4 p9 c( K' o2 w# {
infectious diseases?4 R* ^2 V* X& D5 p1 @
25. Do you agree with banning on wildlife trade for a long time? Whether it' b1 X0 N! W" d8 y' M' q9 X
will have a great impact on the economy and society, and why? 0 @3 c% [0 ?1 S" E' r, K. X6. Write a letter to the relevant departments of the US government to explain / l, Y4 I4 b6 e" [( J9 @your views and policy suggestions.- N9 @0 w r6 j6 h8 R
& r6 n# p' {- e }$ \5 J " j c) X, {2 ?" A1 _. `! ]" j7 h$ L : B1 h( o' B- s 3 j* P+ ^1 Q( x * M1 d; o5 _, W2 u o9 U 1 b$ } b# R* C y- E2 L! o b" a% b+ q0 r: O