2022小美赛赛题的移动云盘下载地址 - @* C0 m5 e& @: I2 ~6 |1 L
https://caiyun.139.com/m/i?0F5CJAMhGgSJx d' k9 Y0 ^. h" l3 ~9 [
3 V4 W$ n: n; K8 }1 @
2022- Y" S, o. N$ |: C) a
Certifificate Authority Cup International Mathematical Contest Modeling $ w6 i' T3 k2 S; a% A8 N# I- Lhttp://mcm.tzmcm.cn& M6 n1 }5 H3 I& t% L& M. N/ g
Problem A (MCM)5 t$ B* F2 d5 V6 o. z: p( h/ j& Z9 O
How Pterosaurs Fly 2 w1 Q# `5 r$ ^Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They7 j7 k2 H" k. k$ Q
existed during most of the Mesozoic: from the Late Triassic to the end of ' T! u5 A1 e! \' y- A% dthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved 3 L1 t& l2 o; a5 Q4 V$ dpowered flflight. Their wings were formed by a membrane of skin, muscle, and - h( g# B- o( v& jother tissues stretching from the ankles to a dramatically lengthened fourth % Z' I; d2 q" c; ^fifinger[1]. + {6 W% s$ V2 m. _$ a6 TThere were two major types of pterosaurs. Basal pterosaurs were smaller ! F! P" f5 b# m9 y& |; Canimals with fully toothed jaws and long tails usually. Their wide wing mem * P: B: w- R) K2 `8 N' I9 Pbranes probably included and connected the hind legs. On the ground, they, M+ {; b& h; m; ~) ?% x! c
would have had an awkward sprawling posture, but their joint anatomy and 1 D: Q* }! J1 ]$ @strong claws would have made them effffective climbers, and they may have lived ( @- x! o' I y* P2 Xin trees. Basal pterosaurs were insectivores or predators of small vertebrates.7 ~% A5 \2 Y# |
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.7 [! j- A( T( ?1 F. [ E# ?; a3 V
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,( A; y7 Q" a, x1 K- I4 m5 X# |! N
and long necks with large heads. On the ground, pterodactyloids walked well on 2 T' A8 r- w" b: z6 l" xall four limbs with an upright posture, standing plantigrade on the hind feet and ) W/ V2 R% s# ~/ ?1 e8 B7 L; V @ efolding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil 3 H6 H! j5 W: C0 i" I3 Vtrackways show at least some species were able to run and wade or swim[2]. ; y& v E8 p+ M2 k* ^Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which) k O. t% u- Q k$ a" D: K
covered their bodies and parts of their wings[3]. In life, pterosaurs would have 7 [6 v# V) f0 `9 \9 xhad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug - s( V( r4 T, Q2 i5 C3 igestions were that pterosaurs were largely cold-blooded gliding animals, de: ~$ N2 Y# Y. e/ q2 u/ O9 r) {: s. B
riving warmth from the environment like modern lizards, rather than burning % h6 g: Y; \3 f( U: icalories. However, later studies have shown that they may be warm-blooded: T" w9 M, k. C& V' S! F
(endothermic), active animals. The respiratory system had effiffifficient unidirec ( c3 r4 r, X/ D- ]5 Mtional “flflow-through” breathing using air sacs, which hollowed out their bones" z, g4 {: C& [9 U4 ]3 r
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from/ Z) o+ f/ L% p* j- T
the very small anurognathids to the largest known flflying creatures, including5 k6 U2 u v# H5 }* M% G/ M
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 8 b q/ P! }1 f, s" W# G! Z7 A& h5 Anine metres. The combination of endothermy, a good oxygen supply and strong 9 H7 c( m p- V m# R( {1muscles made pterosaurs powerful and capable flflyers./ I$ |8 b- S( j. F
The mechanics of pterosaur flflight are not completely understood or modeled 2 l& n" \; j- M+ Sat this time. Katsufumi Sato did calculations using modern birds and concluded( f+ n! T- m. \5 {9 {
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture, 4 A$ i. F/ n" E8 r! SLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able : }, [( R8 f5 ]( ^+ Uto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. ; n; q! v3 a" LHowever, both Sato and the authors of Posture, Locomotion, and Paleoecology3 `9 L/ S3 C4 H6 u: r6 }' \$ W
of Pterosaurs based their research on the now-outdated theories of pterosaurs * R- h( z0 G$ r$ N$ F% ^being seabird-like, and the size limit does not apply to terrestrial pterosaurs,2 W, _) N4 b, j6 \' V
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that9 g. R! V" d b3 v i8 E \" ~, _4 s
atmospheric difffferences between the present and the Mesozoic were not needed ! k* v7 ?2 p+ d" {5 D( m4 w* c7 y6 y4 xfor the giant size of pterosaurs[8]. 1 [: K% w6 i) w$ N3 r2 U% @+ D; L4 DAnother issue that has been diffiffifficult to understand is how they took offff.! v' F, M# `# O& r* z) f
If pterosaurs were cold-blooded animals, it was unclear how the larger ones $ g1 q# \" O: L! O f/ M% g7 ?of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage" W2 j; W7 v0 H! C$ S' z8 G
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for. W5 K4 N9 W' a, [; _
getting airborne. Later research shows them instead as being warm-blooded! F, N8 J7 }. [2 E
and having powerful flflight muscles, and using the flflight muscles for walking as 4 O3 A$ d' o% o7 y% T. Vquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of/ p( ]( ? ?3 }* S
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism7 B& j% Z; d! J) u) O$ _
to obtain flflight[10]. The tremendous power of their winged forelimbs would 3 M' k5 `1 w* n' D- X, \enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds . C- `6 T Z6 t- p. R, J; bof up to 120 km/h and travel thousands of kilometres[10].: ?# p! C8 `% V4 G9 ]3 ^
Your team are asked to develop a reasonable mathematical model of the E$ `& Q" L4 a" T% [flflight process of at least one large pterosaur based on fossil measurements and ' Y: |) \; `/ c; V/ Z) f3 N) kto answer the following questions. 1 J; A) D* a% O1. For your selected pterosaur species, estimate its average speed during nor; o! q7 E. G) n; {/ n
mal flflight.# j' z: d9 c) b; v% v
2. For your selected pterosaur species, estimate its wing-flflap frequency during& k( y W5 [. R
normal flflight./ m4 N# O" Y3 W4 _5 N
3. Study how large pterosaurs take offff; is it possible for them to take offff like 6 C% q$ W) i" T1 obirds on flflat ground or on water? Explain the reasons quantitatively. ~% h; h5 P! W, O1 i: w9 m3 _References: s: H. l) M# X4 F
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight3 {6 M7 U# d6 A H/ e
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111.' g9 x5 N# O& o; t0 H5 a- ^
2[2] Mark Witton. Terrestrial Locomotion.# M% D' i/ E/ J/ V
https://pterosaur.net/terrestrial locomotion.php; `5 K9 b" _" s& w% x$ c. d2 p
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs ' `0 C. N8 u! m! Z/ cWere Covered in Fluffffy Feathers. https://www.livescience.com/64324- 6 c3 X8 q, W; o3 b' e$ \7 ypterosaurs-had-feathers.html8 r4 ?3 q3 v0 ~
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a" M. J8 K: E5 ]0 A
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) & ]/ I' V) }1 S; j; q( Y: ifrom China. Proceedings of the National Academy of Sciences. 105 (6): % ?9 Y) T( u) R6 y- ?1983-87. 4 ]9 O8 E/ P3 I* i9 W. n2 P[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust 6 p4 q$ h- V6 b- O# K nskull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):" X7 u; J& i! a, P2 p
180-84.) {* F4 L* K, K
[6] Devin Powell. Were pterosaurs too big to flfly?1 {; s& v) F. {8 n
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs ; j. u, F# M: o8 n, A) P |too-big-to-flfly/3 A: ^ O! I+ Y3 d. N3 w" F
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology 0 ?& T" v8 V' i& s$ e R& Dof pterosaurs. Boulder, Colo: Geological Society of America. p. 60. 0 U! K. p% ]8 s/ Y R* ^[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable& l" M$ g% B* I$ U) {
air sacs in their wings.8 C2 H0 J; l$ u' H
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur) p3 K& D0 W5 X# y/ U
breathing-air-sacs4 z: y; N) z* _ j: g
[9] Mark Witton. Why pterosaurs weren’t so scary after all. * z5 ?& K5 u$ u% bhttps://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils+ c1 q3 u; O, ]3 j: ] Z& m- C3 a+ W
research-mark-witton 0 [, Y0 Q' h; X8 `# B[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?1 L% v0 y# A, R2 }6 b( u
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs* I6 R# n7 V5 T, y* q( z/ U
vault-aloft-like-vampire-bats/ # S% s3 D+ U6 D0 s/ s% M9 W 3 c" E! R* Z8 r: [2022 1 W& X, \1 F" C- Q, X, R7 \8 Y' t; m/ kCertifificate Authority Cup International Mathematical Contest Modeling ( x8 O3 q e. t& ohttp://mcm.tzmcm.cn # X9 F( E/ p' m* ]7 CProblem B (MCM) * {/ }) a0 u1 q+ {7 g) y% gThe Genetic Process of Sequences" ^* s* W/ u# N0 X3 I
Sequence homology is the biological homology between DNA, RNA, or protein8 d( L/ g# a& i. L* D
sequences, defifined in terms of shared ancestry in the evolutionary history of& ^ I2 o {; i# v; K+ @) u6 F
life[1]. Homology among DNA, RNA, or proteins is typically inferred from their) K2 o1 f$ y: v+ L9 o$ e. i
nucleotide or amino acid sequence similarity. Signifificant similarity is strong( w6 Q6 {4 z! t6 L) E4 o
evidence that two sequences are related by evolutionary changes from a common( j2 I+ `# D9 @& e
ancestral sequence[2]. : ~+ }- W' ^" A9 f# m4 {7 @Consider the genetic process of a RNA sequence, in which mutations in nu / S! @$ I M8 N# D6 ^2 H7 ]cleotide bases occur by chance. For simplicity, we assume the sequence mutation 5 G' ]+ |% X; harise due to the presence of change (transition or transversion), insertion and " K' s2 g# s' L+ }deletion of a single base. So we can measure the distance of two sequences by0 p1 C P- A4 E% j% g$ _5 U
the amount of mutation points. Multiple base sequences that are close together5 o* P8 o3 l! i0 u; P& i
can form a family, and they are considered homologous.1 S" J6 Q' y5 n# g
Your team are asked to develop a reasonable mathematical model to com* J% @. p* J/ B
plete the following problems.( V7 W6 J1 B" B" Z- N1 I7 C
1. Please design an algorithm that quickly measures the distance between1 \2 q5 B" u# I. H8 J! D" J
two suffiffifficiently long(> 103 bases) base sequences. 7 c' a6 y* x( y7 S# ^2. Please evaluate the complexity and accuracy of the algorithm reliably, and* X3 C# Q. F8 E/ V6 k9 h& Z1 @; y
design suitable examples to illustrate it. / v( N* d6 D0 [% K s, h/ V k3. If multiple base sequences in a family have evolved from a common an & [/ e1 I9 T0 S2 i1 U& ?cestral sequence, design an effiffifficient algorithm to determine the ancestral 3 ^3 O# O$ A7 c8 Z7 Y4 ^# f7 Xsequence, and map the genealogical tree. 5 \+ \$ m2 G3 V Q# C$ H1 k. hReferences( `# s! f" D4 v7 u# T9 Z6 f# p, x
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re ' v+ n Z: m1 b' dview of Genetics. 39: 30938, 2005. 2 d+ t& Q3 N) z3 U' E[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,7 `: G& ]) @" K* f$ T+ O3 b
et al. “Homology” in proteins and nucleic acids: a terminology muddle and ^2 y' u! s1 k; d3 s- C# [
a way out of it. Cell. 50 (5): 667, 1987.9 l2 S% h: E7 c3 b, U# ~
! u& `' {* j F% q
2022 , t9 M8 S. Y+ mCertifificate Authority Cup International Mathematical Contest Modeling * M6 t/ k t( t0 Vhttp://mcm.tzmcm.cn6 B/ _, D q) K( E0 |: j
Problem C (ICM)& R) J, W0 z1 L9 K
Classify Human Activities! T! V& H$ \- g) z k% B
One important aspect of human behavior understanding is the recognition and ! r7 Q; F9 ?* G- a- x# V. Y$ Rmonitoring of daily activities. A wearable activity recognition system can im" @; d3 N& a$ G3 s# m0 y
prove the quality of life in many critical areas, such as ambulatory monitor , ]; m, w9 `2 N+ I0 o6 @ing, home-based rehabilitation, and fall detection. Inertial sensor based activ " @4 Z, A4 n: }! kity recognition systems are used in monitoring and observation of the elderly 5 b, H7 K% Y3 E! f: P* c. A* premotely by personal alarm systems[1], detection and classifification of falls[2], + M! }* m, C4 x& H$ a1 dmedical diagnosis and treatment[3], monitoring children remotely at home or in 6 h, G/ }2 K* [0 @. ^# W" B. jschool, rehabilitation and physical therapy , biomechanics research, ergonomics,* d3 P5 d7 f- ~* z5 j# g
sports science, ballet and dance, animation, fifilm making, TV, live entertain& \- T3 i) L n* R
ment, virtual reality, and computer games[4]. We try to use miniature inertial - i; Y* `3 K) W" M0 U4 osensors and magnetometers positioned on difffferent parts of the body to classify" v0 F# F( f3 Y7 o0 `
human activities, the following data were obtained.1 @$ w+ b# I9 V6 F P; i6 B* f" \
Each of the 19 activities is performed by eight subjects (4 female, 4 male,3 N% N% U9 y- _3 Y/ r) r
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes 4 m0 a3 y/ J1 a n! L/ D- ifor each activity of each subject. The subjects are asked to perform the activ . _3 Z4 i8 h" gities in their own style and were not restricted on how the activities should be( I) x8 P/ a/ b7 @: S3 h" S! H
performed. For this reason, there are inter-subject variations in the speeds and . h; a- q8 _& s1 B' H/ `! oamplitudes of some activities. 0 Q8 R3 O/ z" Z! ~+ ^2 t0 Z1 YSensor units are calibrated to acquire data at 25 Hz sampling frequency. ) h- B1 m3 D" EThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal6 O5 [; u) B. _
segments are obtained for each activity. W" s9 \5 D t% K
The 19 activities are:7 U3 Y7 Y1 l5 ?
1. Sitting (A1); ^3 i4 ~3 m, w2 b6 w7 h2. Standing (A2);% ]" L" W: U. |
3. Lying on back (A3);5 ~: x) k- K$ V A2 Q+ |3 Q* M( y; ^
4. Lying on right side (A4);, q" B% Q* J/ x1 s2 |6 V2 \! A
5. Ascending stairs (A5);2 r' |1 a j$ \
16. Descending stairs (A6); + k: M9 K: ?6 z+ a7. Standing in an elevator still (A7); ! P; m3 a5 s' u+ L g1 {- t' U8. Moving around in an elevator (A8);+ M7 m+ \+ t6 \2 ]1 K
9. Walking in a parking lot (A9); 5 d$ f* D" O4 L3 z( r, `# A0 {10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg , F! i1 B \- \$ X) einclined positions (A10);* a( _' d5 t. M3 E% P1 e. V
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions% C6 r' A& z$ _# P: v
(A11); & |, C- ^' V6 n8 y12. Running on a treadmill with a speed of 8 km/h (A12); 7 U2 g5 j' t6 x4 B" v2 t13. Exercising on a stepper (A13);, o* B% S- Z4 |
14. Exercising on a cross trainer (A14); " q5 w: n: i( L* z3 c! n: o: e15. Cycling on an exercise bike in horizontal position (A15); & N/ ]) o+ H( Z$ v7 V: C16. Cycling on an exercise bike in vertical position (A16);/ I' E( @8 c6 N3 @/ C: R
17. Rowing (A17);# T, D0 S7 k8 r# R7 z
18. Jumping (A18); # w' V8 p' J+ t! B" M; U% ]/ o' _19. Playing basketball (A19).- E5 j+ s. G/ g" C% L
Your team are asked to develop a reasonable mathematical model to solve `! R% e3 M9 U, c1 Pthe following problems. - q0 Q9 R" F1 Q9 ~1 V2 x9 }; D8 J1. Please design a set of features and an effiffifficient algorithm in order to classify7 O: a w6 V8 f- \
the 19 types of human actions from the data of these body-worn sensors. / E z3 {% ?4 q; {% J0 ]2. Because of the high cost of the data, we need to make the model have7 T/ W4 |& \7 b
a good generalization ability with a limited data set. We need to study / [* Y9 e( w0 zand evaluate this problem specififically. Please design a feasible method to ( W9 Y+ ~" W& Levaluate the generalization ability of your model.# ?# B9 E2 t) [& V0 v/ V
3. Please study and overcome the overfifitting problem so that your classififi-( w( z9 n" L- T0 k+ C
cation algorithm can be widely used on the problem of people’s action$ x+ J8 y0 P9 ]' s1 ~0 {
classifification.! U8 \3 E0 V) G4 P6 u
The complete data can be downloaded through the following link: 0 a) [% t+ M1 j: z# ]# ~! w6 Fhttps://caiyun.139.com/m/i?0F5CJUOrpy8oq, R) B4 W& a! c& c: Y
2Appendix: File structure; W+ H+ W' }/ {2 ?+ v) Z, w- @
• 19 activities (a) 6 _0 B- T6 X: I# w' u" ~1 f- M; b• 8 subjects (p) 9 ~, v6 i5 L+ p1 C+ C8 o• 60 segments (s)' V% g6 ?1 ~" {" y0 R
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left ( X& C& I" q; ~: yleg (LL)" [) G; F: Y/ {& F8 T1 E& [
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z' X% U1 J4 y+ D! l$ s; p0 d" G
magnetometers) ' u/ s+ d# y' l& ^3 i* x5 fFolders a01, a02, ..., a19 contain data recorded from the 19 activities. 9 ~3 T5 R) ?1 }8 n7 ~$ R+ \$ C+ HFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the 8 \: Z1 O4 H" n. Q9 p$ A8 subjects. ' C) ]1 v; Y; v7 a2 I/ y- XIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each8 M7 M$ A4 ?3 s) G8 w; m0 U; R
segment.9 ?6 Z% k; x% d4 |/ R
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25& I$ w4 |/ b& z; y9 J& Z: a7 W
Hz = 125 rows.; A m$ X+ a: Z7 n
Each column contains the 125 samples of data acquired from one of the# Y ?0 R0 D1 u7 @
sensors of one of the units over a period of 5 sec. 5 c3 j3 o5 a; w/ b, G8 \# wEach row contains data acquired from all of the 45 sensor axes at a particular + s6 G: y+ l9 nsampling instant separated by commas. 4 l8 N; p- e0 L6 {: R4 n( {: NColumns 1-45 correspond to:. ?, Z6 ~' `. y! g8 D( g) G7 a6 V1 _
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,4 Z' }7 x* y( S- G0 r" A9 t
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,# D: w6 h7 N. P* {
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag,$ F- F7 J: V" M" \
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,3 } j; O6 [* C9 |0 X; }$ |. A% [
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.3 \$ D2 `; U$ \5 _9 C
Therefore, ! ], ?, Z C7 m J. I+ r• columns 1-9 correspond to the sensors in unit 1 (T),! c( b3 q5 @. b4 q5 h1 W
• columns 10-18 correspond to the sensors in unit 2 (RA),- K6 H% V9 m- X5 n3 v/ a" h0 }
• columns 19-27 correspond to the sensors in unit 3 (LA), 1 ]2 y9 i5 y8 B! g, }0 R9 D) }! U• columns 28-36 correspond to the sensors in unit 4 (RL), , F7 d0 y, M$ r• columns 37-45 correspond to the sensors in unit 5 (LL).+ f/ {# X% h% P6 Z# D. i
3References & f1 _3 i5 \* A5 }# x% j2 P( E# `3 G[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic % J/ |; e- d# t! t3 Tdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.% U+ B8 C, b, M5 e4 I+ E, }/ F
42(5), 679-687, 2004- s3 L, R2 [; \1 G
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of ! w, M- h7 g- b# H$ [low-complexity fall detection algorithms for body attached accelerometers. / L$ E& Z% g+ n& P- d. r0 x2 |0 H- TGait Posture 28(2), 285-291, 2008$ o9 Z, G1 g& l* F, k3 T. P8 Q
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag% M; D' f# L" N: R; x+ e" I9 G& W
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.2 v {9 r0 g# L" B. n" L; \
B. 11(5), 553-562, 2007; J8 I8 K; k# y' X
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con - V* }0 p U6 X' s% Q6 x$ vtrol of a physically simulated character. ACM T. Graphic. 27(5), 20080 y9 o2 [' f- i- `1 C
, m: ?% i& @; o5 p2022, q$ B( z* G- V9 \
Certifificate Authority Cup International Mathematical Contest Modeling # U# N7 O1 ?9 r& a- g4 l4 Shttp://mcm.tzmcm.cn 9 [% I" G7 C% {+ A oProblem D (ICM)/ D5 A/ Y7 T4 R9 g; z
Whether Wildlife Trade Should Be Banned for a Long 2 O) u. y. T* L2 D7 v4 }Time 7 ~% S' c* _9 \9 {. s) R2 jWild-animal markets are the suspected origin of the current outbreak and the a. T% s: A& ]3 u B- N2002 SARS outbreak, And eating wild meat is thought to have been a source$ f% K( W7 P4 |& U$ ^6 X8 v" n9 F
of the Ebola virus in Africa. Chinas top law-making body has permanently & j7 q7 r4 g3 m, M H$ y8 Utightened rules on trading wildlife in the wake of the coronavirus outbreak, 4 l6 v: S0 a4 \+ S% m/ R, @which is thought to have originated in a wild-animal market in Wuhan. Some : ?- R* a( { _/ J3 P' ~scientists speculate that the emergency measure will be lifted once the outbreak G5 J, e X# d+ `# \3 e; ^
ends. ; v! u7 X6 R4 D. I% SHow the trade in wildlife products should be regulated in the long term? # f' C6 [) A% e$ l7 S+ oSome researchers want a total ban on wildlife trade, without exceptions, whereas + {3 h% m! N, t& Wothers say sustainable trade of some animals is possible and benefificial for peo0 C# y* N: ~+ J: s
ple who rely on it for their livelihoods. Banning wild meat consumption could . N5 c# P& S3 V. T+ ^* r" B% N: _cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil. s U9 `8 L5 M# M+ e' x7 [
lion people out of a job, according to estimates from the non-profifit Society of* T. a+ p- H/ e8 ?1 R
Entrepreneurs and Ecology in Beijing.6 s0 h8 t* i& H7 @& H! P/ C
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology# O2 w" g' P0 k: W4 v2 v$ L
in China, chasing the origin of the deadly SARS virus, have fifinally found their 9 x' a4 v/ o" z) ?5 L) P# j2 {smoking gun in 2017. In a remote cave in Yunnan province, virologists have% x+ X8 R1 z+ H2 l; @0 x; ~/ _
identifified a single population of horseshoe bats that harbours virus strains with& ]( Z* G" ~( V: T: ~7 x/ D4 C
all the genetic building blocks of the one that jumped to humans in 2002, killing, V4 x4 D( X3 M, w* e4 K0 n
almost 800 people around the world. The killer strain could easily have arisen0 ^; k! l4 B# P! B# U0 F8 o
from such a bat population, the researchers report in PLoS Pathogens on 30& y' d: e2 o$ N. W
November, 2017. Another outstanding question is how a virus from bats in % ^' A1 m5 w* J4 yYunnan could travel to animals and humans around 1,000 kilometres away in & P" s L0 E# f6 t9 vGuangdong, without causing any suspected cases in Yunnan itself. Wildlife % b @& y! S9 U" L# h% y5 H+ R: C! Ptrade is the answer. Although wild animals are cooked at high temperature0 i0 @" J3 ~7 W: P/ B
when eating, some viruses are diffiffifficult to survive, humans may come into contact 9 j9 N z8 H0 E8 M$ N1 `2 Iwith animal secretions in the wildlife market. They warn that the ingredients8 V+ y7 j' U# q) N
are in place for a similar disease to emerge again. + t: t9 \8 w5 v. A; iWildlife trade has many negative effffects, with the most important ones being:4 C7 e4 p3 z, V0 w; r; T( ?7 ]3 X
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS8 K! M: f; g4 W: h
outbreak in 2002.Credit: Matthew Maran/NPL . U2 V+ s. b4 B, Y2 ~, G5 d• Decline and extinction of populations8 E8 D# H* _8 V* x# ?6 A
• Introduction of invasive species8 Z( C% i. Y$ ^7 k: S/ g
• Spread of new diseases to humans* z7 i6 b) @7 \* P2 t2 b" [6 z
We use the CITES trade database as source for my data. This database * |3 i2 e k4 ~contains more than 20 million records of trade and is openly accessible. The - `/ O# k; }1 S+ f& Happendix is the data on mammal trade from 1990 to 2021, and the complete $ G- I3 M8 q1 K, P3 n: Edatabase can also be obtained through the following link:) o6 e6 ^2 P% o7 ]# ^
https://caiyun.139.com/m/i?0F5CKACoDDpEJ % {2 ]- B2 P; c" D1 i9 |: h& xRequirements Your team are asked to build reasonable mathematical mod 4 S, d3 V% B1 fels, analyze the data, and solve the following problems:8 Q9 v) i( A, w0 \, h% _. {/ j. G
1. Which wildlife groups and species are traded the most (in terms of live 4 T' U0 J3 k' W9 z0 |animals taken from the wild)?/ G/ C' w0 ]1 f# {1 |7 ~- B) ^
2. What are the main purposes for trade of these animals? : u: R# ~, J( |7 q) @4 k3. How has the trade changed over the past two decades (2003-2022)? ' P5 b8 g: F0 c- u4. Whether the wildlife trade is related to the epidemic situation of major7 f6 ]8 F* a: w
infectious diseases? K2 p) `' @7 X D
25. Do you agree with banning on wildlife trade for a long time? Whether it' v$ D, U" Z, T _/ K, R6 r9 g
will have a great impact on the economy and society, and why? ' k. R' A# F7 e" v$ I( @) M o$ j' Y6. Write a letter to the relevant departments of the US government to explain " k; J( E0 Q" m9 i* Oyour views and policy suggestions.4 d# C8 T: x# W4 S
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