2022小美赛赛题的移动云盘下载地址 . p. |$ F- z7 }% H# B# g
https://caiyun.139.com/m/i?0F5CJAMhGgSJx ! o$ B" [/ g; R1 ]8 `. G 3 [( Y3 d; ~. P5 `: N2022* A; T) f" l4 w& G% J
Certifificate Authority Cup International Mathematical Contest Modeling / ^% D$ Y! s+ f3 K' \, _2 shttp://mcm.tzmcm.cn 2 Z( w$ t5 n* S! l( Y0 t! nProblem A (MCM): s2 ]& z5 R0 v9 d, |+ \6 s
How Pterosaurs Fly ) Z. g3 c* [3 F! h/ P cPterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They: e7 Z; F0 l# q3 S7 q6 a
existed during most of the Mesozoic: from the Late Triassic to the end of / c3 K: n& g! ]( x+ Dthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved Y; V7 E' x1 b9 }; k+ [! ~+ \powered flflight. Their wings were formed by a membrane of skin, muscle, and8 a2 R* M8 t# X+ ?
other tissues stretching from the ankles to a dramatically lengthened fourth ; y9 d; N3 d6 f: N5 p+ efifinger[1]. 4 l- s( b6 }6 ~. r, O8 sThere were two major types of pterosaurs. Basal pterosaurs were smaller7 B$ j# V8 X! @2 O3 H1 l
animals with fully toothed jaws and long tails usually. Their wide wing mem2 s! | o& _: `+ o8 ^2 ]: S: n6 z
branes probably included and connected the hind legs. On the ground, they$ s' t( n& \! a2 g9 k4 x$ X: V
would have had an awkward sprawling posture, but their joint anatomy and 4 v0 {# ^9 w! S( M8 nstrong claws would have made them effffective climbers, and they may have lived$ K5 K1 _* W; f0 @' b
in trees. Basal pterosaurs were insectivores or predators of small vertebrates.3 I4 N- P* R+ d7 o
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.' B! Z! I% o2 J) D2 N# U% {/ d
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,! u z3 `$ I; J9 i1 c
and long necks with large heads. On the ground, pterodactyloids walked well on* U/ c8 k/ @7 R( X/ C! [
all four limbs with an upright posture, standing plantigrade on the hind feet and0 G5 n0 D+ M% k7 _) c3 r7 J
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil0 O6 y8 ?2 |" G' Y j0 a
trackways show at least some species were able to run and wade or swim[2]. 2 Y' o2 X# l6 Z: A4 U7 K8 [- R ePterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which2 W+ p; N* S) z: g3 U: ^7 @
covered their bodies and parts of their wings[3]. In life, pterosaurs would have ) H) o2 j0 N# j* |9 e3 N8 Q4 phad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug u8 p& q/ q+ {! Cgestions were that pterosaurs were largely cold-blooded gliding animals, de . T. o- K4 S$ }' `$ y$ @6 E; X, Qriving warmth from the environment like modern lizards, rather than burning ( C3 O- d9 E' a3 e. m# C( Ocalories. However, later studies have shown that they may be warm-blooded, b' m! V, {' j: f
(endothermic), active animals. The respiratory system had effiffifficient unidirec! W4 h4 D. y9 k% w
tional “flflow-through” breathing using air sacs, which hollowed out their bones3 o( `0 @7 R8 }: Q
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from/ L( V- R6 f' Z
the very small anurognathids to the largest known flflying creatures, including( J3 @$ {4 R: f$ v& N; Y
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least + L- H8 l( D' {3 P; B$ E8 }. Znine metres. The combination of endothermy, a good oxygen supply and strong M* x! x2 M( ~1 b% l
1muscles made pterosaurs powerful and capable flflyers. $ U! {/ Y' H; }+ j5 o4 `The mechanics of pterosaur flflight are not completely understood or modeled5 P# p: K* O$ Z/ }+ H" q
at this time. Katsufumi Sato did calculations using modern birds and concluded y3 z3 K' j3 a" u
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,$ s# Q3 M+ R t! H
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able . |* B+ k) o* d) x: g, }6 zto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. S0 O/ a9 s, h* k/ J8 XHowever, both Sato and the authors of Posture, Locomotion, and Paleoecology n4 [3 N; U; G P0 y& y6 Y; k
of Pterosaurs based their research on the now-outdated theories of pterosaurs / S' X) y: Q+ h; A1 jbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs,8 q$ l& p" }1 h3 l
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that / Z) \5 B" o5 S7 _atmospheric difffferences between the present and the Mesozoic were not needed( W7 }1 Y. A: v& I, R* F6 v1 R$ F
for the giant size of pterosaurs[8].2 X3 K: ~; ^4 m& F5 k0 }6 m
Another issue that has been diffiffifficult to understand is how they took offff. I6 L' e7 ]- e- p3 S8 m/ r- TIf pterosaurs were cold-blooded animals, it was unclear how the larger ones 1 C( E& L8 c* j1 V; D. dof enormous size, with an ineffiffifficient cold-blooded metabolism, could manage& @% u' ?5 z, O% b
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for 9 G2 I; T" r. L8 j9 Sgetting airborne. Later research shows them instead as being warm-blooded2 x+ M3 w2 Z r, P8 i
and having powerful flflight muscles, and using the flflight muscles for walking as * s; A$ V' i8 Y. |8 `) K, j4 Qquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of+ S) I6 r7 P! @5 Q
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism) }5 D, F: {0 b- G& P
to obtain flflight[10]. The tremendous power of their winged forelimbs would " t* b& a* I6 y$ {( | K. E9 Jenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds 2 a# ^3 z2 o( @3 X+ Aof up to 120 km/h and travel thousands of kilometres[10]. 3 H5 e* k3 \- ]9 M* {8 @Your team are asked to develop a reasonable mathematical model of the 8 a4 f, U6 y! H$ g9 cflflight process of at least one large pterosaur based on fossil measurements and8 N7 J& V5 Q8 E" a8 Y1 t
to answer the following questions. * u* t! t7 W$ ?8 K7 y5 W( X1. For your selected pterosaur species, estimate its average speed during nor * ~6 `+ p) B* a' i- smal flflight.9 p5 [4 V k6 L7 B7 C
2. For your selected pterosaur species, estimate its wing-flflap frequency during 8 q! }) c( V/ `/ [normal flflight. 2 ?! U7 [3 J1 f) T3. Study how large pterosaurs take offff; is it possible for them to take offff like 2 }4 r9 F. c5 x7 m/ k% abirds on flflat ground or on water? Explain the reasons quantitatively.9 _5 V" k2 o8 N5 Q1 E
References * K5 X1 [6 B( s; X# Q2 v[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight $ w& e1 v9 h7 {. D" cMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111.) y. ]% \( Y: I) Y
2[2] Mark Witton. Terrestrial Locomotion. - R( Q* ^8 n3 t8 J1 k# Y) ^+ H% fhttps://pterosaur.net/terrestrial locomotion.php 5 R3 i1 c8 O8 w7 O7 ~[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs3 u6 M; V9 S- j
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324-$ A0 p" x: z1 I2 l- v9 T
pterosaurs-had-feathers.html+ f: \' v* K) S( s& d6 F* ?/ t `1 G
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a2 T( [6 u, d0 Y* f* {7 j+ V
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) 4 j7 d3 {0 s2 L7 Efrom China. Proceedings of the National Academy of Sciences. 105 (6):( M; r& R# W- J7 _
1983-87.! g( A* O9 F' v9 [" J# Y) U/ [# b* y; q
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust3 d4 U" I3 s( U7 U0 G% b4 @
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):) O% }( h, Z3 E$ B
180-84. : W5 ^* {- m( L[6] Devin Powell. Were pterosaurs too big to flfly? j1 x( \8 s- p6 w% r2 j
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs . Q; |( x' o/ w) f0 ?too-big-to-flfly/ 5 ~# w' q \+ _) k[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology 9 y) `; _* ~4 {# gof pterosaurs. Boulder, Colo: Geological Society of America. p. 60., i$ n. G" e7 p( b: T9 r
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable4 R* R5 T9 c0 V7 Y# V- P% D5 J
air sacs in their wings. 3 T% W: l9 Q; {$ i* ~, s# zhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur1 @; S. v: N) M- Y
breathing-air-sacs( A. Z7 H _5 T3 h. p3 Y! V2 W7 C* i
[9] Mark Witton. Why pterosaurs weren’t so scary after all.2 ? f2 J" E4 h' D- J8 o
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils# L5 s- J8 G; E5 F3 d
research-mark-witton* N0 _ `7 M) ^0 c9 u
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 2 W D" N- { U) Thttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs R& V8 s1 [4 i* w& t
vault-aloft-like-vampire-bats/ & z, q0 x! S# F6 `7 ]3 D( k$ o( G8 n' o) v
2022; t5 q5 u) ^0 p7 T! n8 K" K7 D4 T
Certifificate Authority Cup International Mathematical Contest Modeling+ v# t. V: p7 c7 s
http://mcm.tzmcm.cn * w2 F' S1 q, ^8 EProblem B (MCM) : O, s# n, w1 E, L9 zThe Genetic Process of Sequences! i- a: r6 j" H# a, A8 b, ?9 }
Sequence homology is the biological homology between DNA, RNA, or protein# X! t& S% h9 S5 Y, C
sequences, defifined in terms of shared ancestry in the evolutionary history of ; H+ Q v1 e% ]$ i8 i& O& Z$ Nlife[1]. Homology among DNA, RNA, or proteins is typically inferred from their$ w9 r* l& ^. J; E* U. T
nucleotide or amino acid sequence similarity. Signifificant similarity is strong- E: t6 \2 E' J& B4 x
evidence that two sequences are related by evolutionary changes from a common 7 s" C3 g8 q7 v& }) aancestral sequence[2]. ' M- m8 S4 u, y2 r6 AConsider the genetic process of a RNA sequence, in which mutations in nu3 f4 g3 z0 M; m, V6 T1 }* T" e
cleotide bases occur by chance. For simplicity, we assume the sequence mutation ' f& h ^+ ?: s) r' }& S- H% marise due to the presence of change (transition or transversion), insertion and 7 T: p1 F! ^1 J, |7 udeletion of a single base. So we can measure the distance of two sequences by1 T% c5 j0 }4 V
the amount of mutation points. Multiple base sequences that are close together $ m7 T9 T- j( r# }# K" r' v$ scan form a family, and they are considered homologous. 2 P8 b3 M4 l+ n. W7 }, gYour team are asked to develop a reasonable mathematical model to com8 N8 M9 }" Y2 W% f. j
plete the following problems.) O2 E0 z+ y6 A, z
1. Please design an algorithm that quickly measures the distance between % _ H5 e- Z8 z5 jtwo suffiffifficiently long(> 103 bases) base sequences. . l4 L7 c; h" c1 ^# D& ?# ^ u2. Please evaluate the complexity and accuracy of the algorithm reliably, and: @ }* }( }7 p" i$ Z; }/ Y
design suitable examples to illustrate it.6 P. Y# O4 D5 ~$ C0 q- D% @
3. If multiple base sequences in a family have evolved from a common an" d1 y) z* E: G2 o8 Z. Z% t4 A5 B6 b
cestral sequence, design an effiffifficient algorithm to determine the ancestral7 r6 n/ D, Z8 W7 r! k
sequence, and map the genealogical tree. ) u7 ~% E: {7 }+ ]6 hReferences 3 V4 c e8 |9 B4 R0 V4 A2 d( K[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re: D9 f4 a/ ?3 a
view of Genetics. 39: 30938, 2005. , n2 h Z4 a, X6 |* i! N4 I Q[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,+ O- P' O9 ?' t6 a1 y' Q" R
et al. “Homology” in proteins and nucleic acids: a terminology muddle and3 ^6 a \2 b+ R5 W& W0 w! p
a way out of it. Cell. 50 (5): 667, 1987. # W/ c5 A2 Y" {! ^% X- K% }+ F4 a4 o4 a7 E# J* E
2022 : F g5 r9 A0 S5 g u- U. VCertifificate Authority Cup International Mathematical Contest Modeling ; w) w$ C2 G y* |" N8 A B8 Jhttp://mcm.tzmcm.cn 2 n: e: c- f e, I4 [% ^" YProblem C (ICM) : E, O1 y& |. i _& X5 zClassify Human Activities1 ^9 S& s C5 E3 Q+ m4 p* G
One important aspect of human behavior understanding is the recognition and; c& P0 [: U: W" j5 v5 J
monitoring of daily activities. A wearable activity recognition system can im4 P- r9 R4 Q0 T2 |& c+ d
prove the quality of life in many critical areas, such as ambulatory monitor. i: L! ~1 y" |& N
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ) ` S$ @# b. I' G1 o
ity recognition systems are used in monitoring and observation of the elderly5 r5 g7 e* r8 U4 u# D- @
remotely by personal alarm systems[1], detection and classifification of falls[2],0 ~' ~' t- M2 q0 k2 j3 Q8 k3 ]
medical diagnosis and treatment[3], monitoring children remotely at home or in ! m4 a8 k; G7 k, c3 O* lschool, rehabilitation and physical therapy , biomechanics research, ergonomics, H+ _9 R. C! L% dsports science, ballet and dance, animation, fifilm making, TV, live entertain & h4 X4 ^. T: Q! p7 Sment, virtual reality, and computer games[4]. We try to use miniature inertial . P. n. N5 E; k/ ] usensors and magnetometers positioned on difffferent parts of the body to classify 6 H- e6 J) r& q1 |5 {" zhuman activities, the following data were obtained. " E, f+ ^6 S; \7 z7 ?Each of the 19 activities is performed by eight subjects (4 female, 4 male, 5 s, @" l# d; I/ X. {between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes& A+ S( r: i* b' F( Q8 ]9 f4 s+ [4 m
for each activity of each subject. The subjects are asked to perform the activ L5 l. L2 q" K ]/ z! \7 f8 Xities in their own style and were not restricted on how the activities should be ! y/ t& x/ d; j W& [5 Wperformed. For this reason, there are inter-subject variations in the speeds and) P, Z6 l o# {1 n& P# M' y% b0 i6 `' ^
amplitudes of some activities.. T+ `" E4 B7 S0 Z) D( J
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. ) R5 l8 t- u h3 i5 iThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal 8 W% o2 k+ V2 S6 ~$ Psegments are obtained for each activity. : s* R& D/ v$ GThe 19 activities are: ' @7 A ^$ h* S$ X1. Sitting (A1);4 R/ |. C) e6 Y' |
2. Standing (A2); ' D: N9 D: c# H# b# ]2 g3. Lying on back (A3); 6 q4 K" W) @6 P- @4. Lying on right side (A4); - s% w' x, X/ H( u, v$ N5 g5. Ascending stairs (A5); ( n; W$ N8 L9 y. a+ A+ z16. Descending stairs (A6); 6 m# w u" `! u, ^0 q: Z7. Standing in an elevator still (A7); : {5 _& C* g/ }8. Moving around in an elevator (A8); 4 ^; P5 ^1 y- R3 d) q1 ?+ [; s ^9. Walking in a parking lot (A9);+ a7 s( u5 h( B+ b: T) T
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg 3 a+ p7 n! Q3 Q' Oinclined positions (A10);5 f& A' n! \6 t9 }& ^
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions 6 c `/ B' P5 `: G1 \(A11);! O' a4 \+ h. b7 `3 G; S2 h4 S. N
12. Running on a treadmill with a speed of 8 km/h (A12);. U2 p( b$ X x! O; F7 ]
13. Exercising on a stepper (A13); 7 X: O4 j, P- s; ]" w14. Exercising on a cross trainer (A14);3 K- {/ [! n3 k( P9 ]9 v7 X
15. Cycling on an exercise bike in horizontal position (A15);3 m4 u, X# g9 {. M! P5 q
16. Cycling on an exercise bike in vertical position (A16);: S' z2 u) O% b/ n6 c3 K2 s5 s
17. Rowing (A17); 9 u5 W1 T8 a4 W4 _, @' s0 d18. Jumping (A18);- m: [( l8 H2 o
19. Playing basketball (A19). 1 J. t8 I6 ~ R6 U& T6 z! l1 q5 _Your team are asked to develop a reasonable mathematical model to solve1 H0 s( r- W& V% Y- b4 r" E
the following problems.$ u& S. }: P$ d- |
1. Please design a set of features and an effiffifficient algorithm in order to classify G& N5 H: e s b8 ~/ r, othe 19 types of human actions from the data of these body-worn sensors. 1 @! V1 S9 q/ j3 [7 w5 e2. Because of the high cost of the data, we need to make the model have2 H* o6 n" o) ? e
a good generalization ability with a limited data set. We need to study3 B' f5 R# N; @ {3 g1 n: e
and evaluate this problem specififically. Please design a feasible method to " g- l) g3 T+ c8 w0 w$ a L; Eevaluate the generalization ability of your model. 1 l7 g7 |0 i" }5 C* h; g' u ~6 P3. Please study and overcome the overfifitting problem so that your classififi-1 s) V, I3 Q4 @# k# U# W
cation algorithm can be widely used on the problem of people’s action 9 {( l# n5 o3 U; Gclassifification. ( W' n' u$ s5 |The complete data can be downloaded through the following link:" w% k; h) \) l) W" v3 Q
https://caiyun.139.com/m/i?0F5CJUOrpy8oq % t/ @6 a y! c0 |8 Z5 a2Appendix: File structure8 l4 A& H+ W5 u) B
• 19 activities (a)& A6 Z. h5 p+ G2 e/ M; P
• 8 subjects (p) % ]/ t- K: T9 h- ?6 O• 60 segments (s)( g" c0 j3 T! i: T9 H' b1 H1 i& \
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left # V' q- K) _8 ]' `: K6 {8 Nleg (LL)9 O+ D" _0 C6 l
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z, {$ _+ Y$ ~# i$ o' t c2 P
magnetometers) , F$ O3 O: w+ SFolders a01, a02, ..., a19 contain data recorded from the 19 activities. ! w9 H' u( ]1 c1 p9 g- DFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the6 E/ S! I N5 G9 J' C
8 subjects. * F2 U3 x* ?3 Q) M. g+ j7 L% j/ i) QIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each% w1 s" ]* r( }% n. `+ h7 q" \4 x( g; s
segment. 8 I$ |* o% M/ |/ HIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 9 n( V. ~; X aHz = 125 rows.' ^$ S) z3 B8 p' u+ d
Each column contains the 125 samples of data acquired from one of the 4 l3 K* ?& d! @9 e7 C: l |sensors of one of the units over a period of 5 sec.) T6 e# }6 U6 ]
Each row contains data acquired from all of the 45 sensor axes at a particular$ n# s# ~# g# a# x( d( I
sampling instant separated by commas. 0 M: _3 ~3 B$ I' bColumns 1-45 correspond to: 1 L3 R7 s3 C" ?$ M• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, # d* l6 j" _: y1 A$ H' E& [• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,+ F6 F6 C7 \2 k5 V
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag," z+ H) `0 P# h+ l
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,8 L8 V W7 C) @" K& d5 b5 F
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.# d! O( t* E4 t0 ]( N( n1 l
Therefore,4 C+ S6 F7 Y9 R* }
• columns 1-9 correspond to the sensors in unit 1 (T), # z* N. P1 Z# q6 f- a- p* x• columns 10-18 correspond to the sensors in unit 2 (RA), 7 S) g: f% P1 e/ a& G8 J• columns 19-27 correspond to the sensors in unit 3 (LA),* O0 ?, U6 c5 _# n* }6 o4 i
• columns 28-36 correspond to the sensors in unit 4 (RL), ) X7 K U. L7 C8 @" |• columns 37-45 correspond to the sensors in unit 5 (LL). 9 B# `' a7 N. D% {3References B( g9 U! ^8 f- D9 C
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic+ `' U4 l: A, B8 e
daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.3 V4 S6 M; [* Z3 j1 y
42(5), 679-687, 2004 % ~- G$ G2 }' A& b; `[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of/ f- P2 ^8 i k" T5 Y( N# Y! a
low-complexity fall detection algorithms for body attached accelerometers.: }( L7 U2 s4 O
Gait Posture 28(2), 285-291, 2008; _1 l f, b# s- r
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag $ Q2 H" \8 K0 ]# l; t: knosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.4 f3 K+ I8 n6 Z
B. 11(5), 553-562, 2007 * S0 `: u+ E. [[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con ; } Y2 n; v" o$ Ntrol of a physically simulated character. ACM T. Graphic. 27(5), 2008 $ z/ I( u/ E4 e' {% r7 i! b$ w, J ~4 ]! Y8 n- p2 i* m6 [; Z
2022 + f/ X7 @7 f, j( C; t: rCertifificate Authority Cup International Mathematical Contest Modeling9 N$ j" {' v$ T( m$ [
http://mcm.tzmcm.cn 6 O& {5 c/ R0 ?2 y9 E) dProblem D (ICM) 9 I# f: Z7 i; o/ i; { G, w* bWhether Wildlife Trade Should Be Banned for a Long- c1 ]$ C8 A" q; t$ u* @
Time * K ]% U4 U1 QWild-animal markets are the suspected origin of the current outbreak and the / d2 x0 l5 g5 t: j! F- E0 j2002 SARS outbreak, And eating wild meat is thought to have been a source 5 l3 s3 Y& e* Mof the Ebola virus in Africa. Chinas top law-making body has permanently( i% Z6 ]; ^2 l3 {% }' j
tightened rules on trading wildlife in the wake of the coronavirus outbreak,3 T) ?$ `4 z/ k4 s0 ^
which is thought to have originated in a wild-animal market in Wuhan. Some9 D$ z. C+ g0 ?) t
scientists speculate that the emergency measure will be lifted once the outbreak3 {/ J4 k) |' G
ends.9 c5 S- Z$ H+ e2 G) _% B0 ^ W
How the trade in wildlife products should be regulated in the long term? % W1 I. S4 E. R7 TSome researchers want a total ban on wildlife trade, without exceptions, whereas# e' l, M) Z( z/ K/ Y2 X, `: |8 c
others say sustainable trade of some animals is possible and benefificial for peo # v3 `% J" A4 O3 V% Y( J& A; Iple who rely on it for their livelihoods. Banning wild meat consumption could) l0 W! V) Q# m- M, Y
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil : ^3 Z4 Q- \0 e1 Z# D1 Ulion people out of a job, according to estimates from the non-profifit Society of ! T3 B+ f7 t L) V: F# HEntrepreneurs and Ecology in Beijing.: L; p) _) Y4 t" D
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology / D. |) O3 h. b4 h2 Zin China, chasing the origin of the deadly SARS virus, have fifinally found their u6 D" d( Q; N+ M
smoking gun in 2017. In a remote cave in Yunnan province, virologists have . k4 ^0 @7 y m% v& c5 c# xidentifified a single population of horseshoe bats that harbours virus strains with# ], b _6 t& A7 d, T' v# X
all the genetic building blocks of the one that jumped to humans in 2002, killing% k" P# X1 }2 B+ {
almost 800 people around the world. The killer strain could easily have arisen8 T% x# { k" @ J" g5 ^' F/ o
from such a bat population, the researchers report in PLoS Pathogens on 30 6 J( N L" w& {0 y' v+ _1 SNovember, 2017. Another outstanding question is how a virus from bats in ' D+ U, R* H* g* [0 \" nYunnan could travel to animals and humans around 1,000 kilometres away in 8 E1 C, u: M! c3 p6 I9 FGuangdong, without causing any suspected cases in Yunnan itself. Wildlife / H. q0 }8 ?0 q r( vtrade is the answer. Although wild animals are cooked at high temperature$ g J0 b" C& c# R, G0 P
when eating, some viruses are diffiffifficult to survive, humans may come into contact& X# |& Q* t. x1 X
with animal secretions in the wildlife market. They warn that the ingredients . a$ h7 T, D0 _1 P- a$ Zare in place for a similar disease to emerge again.; q' i: c9 J6 w; ]
Wildlife trade has many negative effffects, with the most important ones being:' V% m0 S8 O9 i' N+ x$ r7 r% y
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS+ H$ d. B. v$ h6 z( p4 j- @
outbreak in 2002.Credit: Matthew Maran/NPL - T% r) X9 e U. u* s• Decline and extinction of populations ! ?! O; e% X/ D• Introduction of invasive species( z5 a. E& `2 S4 F9 z- d+ d
• Spread of new diseases to humans ) ?4 t! i2 I. n7 rWe use the CITES trade database as source for my data. This database0 @0 K* _9 _5 p0 G$ U9 v$ i) G3 x' s
contains more than 20 million records of trade and is openly accessible. The - b" {( y2 D' @2 g1 yappendix is the data on mammal trade from 1990 to 2021, and the complete4 l& o* \. e5 W% V
database can also be obtained through the following link:/ G$ s G6 U& F! b
https://caiyun.139.com/m/i?0F5CKACoDDpEJ/ V- `4 Y# L3 t7 z
Requirements Your team are asked to build reasonable mathematical mod 4 P) w) K' k- g, Qels, analyze the data, and solve the following problems: . ]% f9 }/ J2 w1. Which wildlife groups and species are traded the most (in terms of live6 {! M0 t( m9 W+ A% ^
animals taken from the wild)?9 l7 n7 @* Z) L J+ n
2. What are the main purposes for trade of these animals?+ h& q# j9 W' i( h1 F
3. How has the trade changed over the past two decades (2003-2022)? : j( ?9 M/ P8 y% a& M% n4. Whether the wildlife trade is related to the epidemic situation of major$ L" G4 J3 H1 ~( P+ K3 [- H
infectious diseases? 4 C0 V0 E. k$ `) ~25. Do you agree with banning on wildlife trade for a long time? Whether it + T! [$ b; D) `+ A6 s' b4 K$ B8 cwill have a great impact on the economy and society, and why? ) g% y! P( ^; p3 F, @& `: Z6. Write a letter to the relevant departments of the US government to explain 4 Z# a6 B2 E f4 ^* }/ L yyour views and policy suggestions.0 E+ O0 W' K3 _' z2 a4 e6 _% E
' I; G2 x) T/ N9 t3 G, [ ( @! J3 {% y$ E( _6 S7 `! U# @- a" b4 v; |" H. T
2 C( l% A! t' ^$ O) X
8 a, l' @% d; `+ D+ W# Z* \2 E