2022小美赛赛题的移动云盘下载地址 " }# f# S9 w% i. \. ]
https://caiyun.139.com/m/i?0F5CJAMhGgSJx 4 d- m5 ~: P; n/ c4 C9 @8 a& }! u. s; M, d% i; q" W
2022 1 h2 ]' q, Z o! m% LCertifificate Authority Cup International Mathematical Contest Modeling , ~8 \6 D- c& s1 Jhttp://mcm.tzmcm.cn 4 S8 @9 Q6 D* u6 yProblem A (MCM)& A# c6 t" K/ |" |5 z3 a2 i* U2 o
How Pterosaurs Fly / `9 s# a X& ^; j$ q" F4 iPterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They + V* r: S* x+ a2 g3 Sexisted during most of the Mesozoic: from the Late Triassic to the end of( _/ \* q6 b; B6 A m- Z
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved+ ?0 u' B R: U3 _
powered flflight. Their wings were formed by a membrane of skin, muscle, and% ~0 M% B) Y7 x0 \
other tissues stretching from the ankles to a dramatically lengthened fourth$ G/ _# `! t7 r7 p
fifinger[1].0 q& z; |' T6 x/ G* A7 M9 S
There were two major types of pterosaurs. Basal pterosaurs were smaller , F6 D7 @: X4 m ~; c# kanimals with fully toothed jaws and long tails usually. Their wide wing mem0 b5 q& X* A) y+ d7 \4 W
branes probably included and connected the hind legs. On the ground, they l) v# a& ?/ C. o( v8 a3 J
would have had an awkward sprawling posture, but their joint anatomy and ! N& |8 e! u }0 z6 fstrong claws would have made them effffective climbers, and they may have lived$ f% p0 Y' ^( X
in trees. Basal pterosaurs were insectivores or predators of small vertebrates. " ~' G" W8 F8 U9 ?' x2 k4 pLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles., w) A$ T0 t' a) R" `
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,! v6 j& ]/ x5 Z F* U7 F k( W
and long necks with large heads. On the ground, pterodactyloids walked well on+ Y9 W. _# ^9 l& N! Z6 ~ b/ _
all four limbs with an upright posture, standing plantigrade on the hind feet and+ h3 [* N6 O( t* T' B
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil* J6 W( d, N z
trackways show at least some species were able to run and wade or swim[2]. # a6 o" u( ~% [# F# k+ k: P0 iPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which : m& x0 \% B9 p* P- icovered their bodies and parts of their wings[3]. In life, pterosaurs would have 1 r7 r& b( F! d0 e/ }had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug1 l9 }: V4 o( t- r' F
gestions were that pterosaurs were largely cold-blooded gliding animals, de , x6 u5 [! u# g kriving warmth from the environment like modern lizards, rather than burning 9 r- Q$ N8 M5 C7 j' M$ N# ^calories. However, later studies have shown that they may be warm-blooded& X( x1 w3 M4 _
(endothermic), active animals. The respiratory system had effiffifficient unidirec; I& \: h% m c ?- A2 @
tional “flflow-through” breathing using air sacs, which hollowed out their bones ! K$ k$ ^9 C, a3 l6 V3 Bto an extreme extent. Pterosaurs spanned a wide range of adult sizes, from9 }4 O* L# H- x4 P/ D
the very small anurognathids to the largest known flflying creatures, including 2 x- Y* q' A( a1 _1 p5 yQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least ' G9 H) t" y6 E/ t6 M# w6 nnine metres. The combination of endothermy, a good oxygen supply and strong ! h7 v4 k, P* R9 x1muscles made pterosaurs powerful and capable flflyers.) @! H( N2 c8 E! I" D, v! n
The mechanics of pterosaur flflight are not completely understood or modeled 9 t9 J. f7 u5 G/ c/ T5 cat this time. Katsufumi Sato did calculations using modern birds and concluded! K) \% {0 u3 k$ U& y
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,, S& K: Q L! C+ t
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able0 m" c! j/ I# F. e: b2 l7 h
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. & r( g( z6 t5 J4 x) ]! D( [However, both Sato and the authors of Posture, Locomotion, and Paleoecology ; d: V* O$ N% M2 `of Pterosaurs based their research on the now-outdated theories of pterosaurs : ^. G' p. p/ f! U/ J7 m" vbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, 4 g$ K( X5 O; M9 W i/ v; wsuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that 6 d# s1 Q& U9 f9 y) katmospheric difffferences between the present and the Mesozoic were not needed/ \+ L6 z) q- e+ ~
for the giant size of pterosaurs[8].6 S0 q* Z) h/ t3 W) R
Another issue that has been diffiffifficult to understand is how they took offff. 8 X' |5 }1 H+ i* N6 \2 xIf pterosaurs were cold-blooded animals, it was unclear how the larger ones# H, ^6 R8 N+ S1 ^, t1 C
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage( M: o9 g% T. j/ X+ C' |1 O
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for ; ? p! z0 Y( ~# P. U8 r: Hgetting airborne. Later research shows them instead as being warm-blooded( U" P! o# V1 N
and having powerful flflight muscles, and using the flflight muscles for walking as# X1 [& I) ?4 x" f( w
quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of + z& e! [% z! Q( n' B: p% EJohns Hopkins University suggested that pterosaurs used a vaulting mechanism 6 q; ?, P3 V# Q9 F3 Tto obtain flflight[10]. The tremendous power of their winged forelimbs would( `! [' ~# D* n" d# f: |! z
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds% U* Q) v$ K/ c. _. X6 {+ S: {
of up to 120 km/h and travel thousands of kilometres[10].% m8 Q7 [, g; g6 c8 n
Your team are asked to develop a reasonable mathematical model of the8 E. t; N4 v6 p
flflight process of at least one large pterosaur based on fossil measurements and + L! K( s% Y' ~) R. vto answer the following questions. 3 p" y' q, {! u/ c9 u9 b6 m1. For your selected pterosaur species, estimate its average speed during nor 5 S: F7 l/ C& } a: vmal flflight.) L1 K5 Z5 S5 W9 {/ S. v& h
2. For your selected pterosaur species, estimate its wing-flflap frequency during 0 o4 l3 B% v" \$ h% T# Z6 @normal flflight. # o% x1 K5 K3 `5 }+ a+ F1 E, n# A3. Study how large pterosaurs take offff; is it possible for them to take offff like 6 s7 v. Y+ P- [7 f9 ? c+ `birds on flflat ground or on water? Explain the reasons quantitatively. $ \3 `- U; F2 d. B BReferences3 I0 L/ L! C: Z
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight - L. ^. K4 l V4 H4 j& ^/ @9 PMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111. $ @( A4 A- A3 g: V: T4 V" {2[2] Mark Witton. Terrestrial Locomotion. 3 a( v! _0 r! ?" J9 {5 I5 ^5 Z1 fhttps://pterosaur.net/terrestrial locomotion.php& m [$ y( ^; i
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs 9 D! b* T, F- @6 b# |: kWere Covered in Fluffffy Feathers. https://www.livescience.com/64324- % R3 n0 K3 Z2 ~& T/ A% { W7 ^9 jpterosaurs-had-feathers.html; e) v' v/ e& B$ m0 E* ]
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a* A! P, t$ \$ K0 L# r( }3 l: F
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)! y6 y9 j. c1 b+ w& U
from China. Proceedings of the National Academy of Sciences. 105 (6): 4 L/ E; U" I, ~' ^1983-87.% G5 ?/ P) Q4 H) b+ e- f( J! T
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust " \/ R6 L3 }" Pskull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4): 9 \" M+ J1 p- a7 q180-84. / @; ?* ?$ \) A: R( s8 J) c0 U[6] Devin Powell. Were pterosaurs too big to flfly?9 C( F2 _2 W) i1 P: }9 x
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs: o, I" x/ o- z
too-big-to-flfly/& m! ?! q8 v: m
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology& l( D1 ^9 k: {( n' \0 v9 \; B- H, F
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60.2 Z! z, K4 R3 n3 h5 R7 N- {
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable . T' `7 a* l- Hair sacs in their wings.$ Q9 @) A( `, _% }1 g
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur# O2 B$ X4 g& [7 E/ u
breathing-air-sacs 3 o. l r; [* L[9] Mark Witton. Why pterosaurs weren’t so scary after all. 1 Q* T0 x# d9 H9 S; r: Fhttps://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils : o. V6 @5 J4 O( J- G8 N7 x0 b$ G* bresearch-mark-witton# k9 w- c* z4 @/ m
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?8 i/ z2 u2 ]& V+ k
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs 7 u% `% e, b' D1 }( L& Ivault-aloft-like-vampire-bats/- F( T2 Z" N% M' V" q6 X
^; F' ~% x* L3 h2022 + r0 Y' s" c9 I! J* Q3 v2 R2 m" ?& yCertifificate Authority Cup International Mathematical Contest Modeling 2 J6 [: S7 j }5 l& yhttp://mcm.tzmcm.cn, y+ V3 s* t T$ @
Problem B (MCM) / M7 {; s: H' c! aThe Genetic Process of Sequences" Y' j: j: N9 z! Y! d
Sequence homology is the biological homology between DNA, RNA, or protein# S/ d3 Z7 C" V# e9 a7 x0 }* z/ f
sequences, defifined in terms of shared ancestry in the evolutionary history of N, O, n# y9 S3 U8 H% h) Ylife[1]. Homology among DNA, RNA, or proteins is typically inferred from their ) m( q5 o6 z; U9 s9 N. ?+ G2 Q3 inucleotide or amino acid sequence similarity. Signifificant similarity is strong + L$ T+ s' A% x6 h9 \4 c9 Fevidence that two sequences are related by evolutionary changes from a common5 S+ C* q( A) \, a
ancestral sequence[2].9 p& }) U! w3 u' E* X6 a
Consider the genetic process of a RNA sequence, in which mutations in nu( Z7 p; B9 K" Y z* P" L
cleotide bases occur by chance. For simplicity, we assume the sequence mutation . `5 G7 V! m- ~5 Narise due to the presence of change (transition or transversion), insertion and 0 ^2 v9 P8 m" }' ideletion of a single base. So we can measure the distance of two sequences by ) W6 H+ H& s. u* B7 Q6 @the amount of mutation points. Multiple base sequences that are close together ! `6 J a" z" Q1 }can form a family, and they are considered homologous., v: f: {, o( d9 {8 z m& K& ~! m
Your team are asked to develop a reasonable mathematical model to com 4 {7 c: y) W' }4 O/ {. a! T; oplete the following problems. + h/ K" F- [' \1. Please design an algorithm that quickly measures the distance between & F3 G) j( X( d8 G ]+ H, {. stwo suffiffifficiently long(> 103 bases) base sequences. 5 Q, U7 q; |+ _( E1 l2. Please evaluate the complexity and accuracy of the algorithm reliably, and 7 ~! z9 _) [( h9 ]) x$ l, B! Rdesign suitable examples to illustrate it. 5 D: P' K% o" O( H3. If multiple base sequences in a family have evolved from a common an! \2 Q. a: G1 X; Y# G* A
cestral sequence, design an effiffifficient algorithm to determine the ancestral) J$ n* c# E6 _
sequence, and map the genealogical tree. $ C* h, P0 W& x! WReferences / C' g7 @+ R9 l[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re4 m9 z2 Q9 A! z, l
view of Genetics. 39: 30938, 2005. $ B9 T$ v, d6 b7 Q! Z[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, 6 t0 G+ l6 Y9 K! @, E: _" eet al. “Homology” in proteins and nucleic acids: a terminology muddle and* O1 z/ n( w/ s" J, S( e- ?* W
a way out of it. Cell. 50 (5): 667, 1987.9 P$ @1 c- P( M- v; d5 l
& w4 s5 m( d: W* s5 B/ w2022# Y! X1 l. @- Z3 T
Certifificate Authority Cup International Mathematical Contest Modeling! K0 ^& i% F7 s ^$ ~4 A
http://mcm.tzmcm.cn* C; Y/ H6 W+ A; F
Problem C (ICM)4 U. `4 k& e/ o6 k* }
Classify Human Activities0 f! B0 [4 ~4 y+ x+ Z
One important aspect of human behavior understanding is the recognition and8 J8 ]8 [+ z& J9 m' Q
monitoring of daily activities. A wearable activity recognition system can im0 ^( y3 `2 s. y0 u3 T% R/ K. L6 \
prove the quality of life in many critical areas, such as ambulatory monitor+ ]: r2 H1 Z: ?7 Q5 t
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ 5 ]& ~" w( _- [+ ~7 I w! Qity recognition systems are used in monitoring and observation of the elderly8 o& A, o" `& n/ @) B3 z0 ^0 T/ u, C
remotely by personal alarm systems[1], detection and classifification of falls[2],( w0 A ]3 f6 d/ x" q/ c
medical diagnosis and treatment[3], monitoring children remotely at home or in f" l2 p" Y' h8 D; g1 `5 A
school, rehabilitation and physical therapy , biomechanics research, ergonomics, 7 `4 Y: N, Z' T8 L7 msports science, ballet and dance, animation, fifilm making, TV, live entertain+ ~7 ~ T P8 I- T) Y
ment, virtual reality, and computer games[4]. We try to use miniature inertial+ N$ ?2 q m' B( g' v
sensors and magnetometers positioned on difffferent parts of the body to classify# @" X. S) S, ^. w4 i7 F: x; O6 h
human activities, the following data were obtained.$ R( r# @: t) l5 i
Each of the 19 activities is performed by eight subjects (4 female, 4 male, ) ~0 p# x W' P: Sbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes- k. `( t( B, L3 `) [3 |0 q1 r
for each activity of each subject. The subjects are asked to perform the activ ( Z" H) ?( b. a( bities in their own style and were not restricted on how the activities should be 2 D2 N, T; V( c% b' f% z& wperformed. For this reason, there are inter-subject variations in the speeds and0 K$ x' {2 M/ ?1 z+ E' ^, ?
amplitudes of some activities.$ W7 b, u0 l" |1 d* O1 V ~
Sensor units are calibrated to acquire data at 25 Hz sampling frequency.! ?$ f3 @0 ~3 E1 e4 e: i9 y
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal6 o3 t' q2 r+ u1 {3 f: \3 E
segments are obtained for each activity." W v) X. o; }$ |4 x' y1 i
The 19 activities are: + v1 Z" I; S8 X R" u0 r1 F: i r1. Sitting (A1);+ _+ Z( Z4 u* H
2. Standing (A2); * w% E. i+ F* \* R: c3. Lying on back (A3);# X3 |; ~5 c" ^, W% A! K
4. Lying on right side (A4); + }$ e- ]6 k( ?1 j# P5. Ascending stairs (A5); 4 N! m" J; w0 s, {1 \4 v) y16. Descending stairs (A6);; `) V i: K4 T
7. Standing in an elevator still (A7); - C1 M$ C% A. J7 d c8. Moving around in an elevator (A8);/ f d/ \. G8 ?: F6 b
9. Walking in a parking lot (A9); 9 E0 s; Q5 I, N1 X10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg! v2 S" O, G- m
inclined positions (A10);% k9 k* b/ T2 N# V1 m
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions9 }6 ^) E, K( C$ e5 F( S4 d, i7 }
(A11); ) C* c3 @8 f# v2 i, w E. ^# L. B12. Running on a treadmill with a speed of 8 km/h (A12); % q7 V: Y) |" h13. Exercising on a stepper (A13); : K; O' |) i4 A6 s1 e0 z N) H14. Exercising on a cross trainer (A14);* u+ h7 d% @% p: `2 I$ G
15. Cycling on an exercise bike in horizontal position (A15); : t$ q: k1 p1 [, ]16. Cycling on an exercise bike in vertical position (A16);# g! _6 X) w, x, C% W' K! G3 c0 ]
17. Rowing (A17); 5 o, M' R8 I5 T- G! x18. Jumping (A18);7 h& s9 Q' |1 F5 q
19. Playing basketball (A19). . x) h: `! I k- e" s1 n( v4 KYour team are asked to develop a reasonable mathematical model to solve+ I! y- y3 J( [1 U2 I3 e& J; L& p
the following problems. + y2 G; J$ G1 t( W0 i* Q5 Y& a1. Please design a set of features and an effiffifficient algorithm in order to classify , ^+ @, I9 \* t. G8 |: S( v8 @8 q8 |" kthe 19 types of human actions from the data of these body-worn sensors. 3 m! m# m1 M2 d2. Because of the high cost of the data, we need to make the model have& e" V1 _7 F$ g. v
a good generalization ability with a limited data set. We need to study$ u2 `/ z5 ~+ d" T& ]* U: Z
and evaluate this problem specififically. Please design a feasible method to J* V- x9 F8 W i Y1 e0 o( {2 P5 Oevaluate the generalization ability of your model.2 G5 @& Y/ X1 I/ l0 V
3. Please study and overcome the overfifitting problem so that your classififi- / b1 h# C7 b1 I1 wcation algorithm can be widely used on the problem of people’s action. C3 H5 X8 }- r5 Z+ u
classifification. , x. k+ P6 Q/ L# H8 WThe complete data can be downloaded through the following link:# J( }4 @$ t4 A# g. X3 J/ b5 B% g
https://caiyun.139.com/m/i?0F5CJUOrpy8oq I- B/ A2 V# n7 R, @
2Appendix: File structure ) k0 V( l$ s: x( g• 19 activities (a)) ^: [+ U8 J. h
• 8 subjects (p) & P0 k. s) y1 H) S+ L• 60 segments (s) ) J# c9 R& A# g! P3 A• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left- t2 I# g) a. M9 g n% w- l% e3 a
leg (LL)9 L7 k+ W( V+ K$ B
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z; |0 T1 ]* R( y
magnetometers) - S" z [5 \ TFolders a01, a02, ..., a19 contain data recorded from the 19 activities. * w+ x4 P' _; g0 W/ w! p" x \8 QFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the : \% Q F& m6 Q+ G8 subjects.( w6 R* e5 \+ `9 c5 U5 N; h* r
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each 0 B5 B0 X) _$ t _1 [+ C @segment.$ s4 V5 n% G0 } l
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25/ Z r) R3 N1 W3 `
Hz = 125 rows.- ^+ I h$ \$ ~2 F# D
Each column contains the 125 samples of data acquired from one of the ' x5 ~9 a0 ?0 ~; r9 k% a3 H( lsensors of one of the units over a period of 5 sec. + g' _# E- A* C- y9 K4 A6 n# jEach row contains data acquired from all of the 45 sensor axes at a particular0 X' L- z2 P( P2 ~* G; [! ?4 H
sampling instant separated by commas.. ]- n( y0 R. _$ r ^* F: H7 m2 l+ m7 A
Columns 1-45 correspond to: & I: `( A& `1 F6 ]- G• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,7 B \; A! H5 D' \2 L8 u
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,8 K/ ^# j5 S' S+ n+ G7 S3 y' W
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag,4 o: y$ r: t0 r1 f2 b2 f8 T% ^ O. q
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, 2 C+ e& W2 y5 G, h• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.& c' Z9 I8 ~4 `) y
Therefore, , Q9 f0 o1 ~5 J0 b# H. b$ F6 G* b• columns 1-9 correspond to the sensors in unit 1 (T), 6 c1 N, J+ v. o% \, ~& {5 z• columns 10-18 correspond to the sensors in unit 2 (RA), 3 J1 [ I2 ]" z• columns 19-27 correspond to the sensors in unit 3 (LA), " N* R& x# l5 q- V7 x• columns 28-36 correspond to the sensors in unit 4 (RL),0 f1 {3 @) j4 J3 ~. |/ c
• columns 37-45 correspond to the sensors in unit 5 (LL). 9 x" m! o5 k: Q" k3References( O( D; P! W8 ?' {
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic + x4 |4 o8 S1 m/ p6 _1 X0 [3 r9 rdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.) h" K: z' b( M! ]6 N4 F3 }2 R
42(5), 679-687, 2004 . w3 }9 |4 _4 w2 Y[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of4 S$ \8 ^# q+ i/ k9 j0 x
low-complexity fall detection algorithms for body attached accelerometers. 0 j2 e( L3 i/ r# n. N7 PGait Posture 28(2), 285-291, 2008 . [/ ]. T0 q! T' s& L+ w; Q& |" H[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag 8 Q7 w4 [4 @: h8 gnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.9 a* V$ K8 x/ u! a9 W( o- v
B. 11(5), 553-562, 2007 ' P9 B9 ?5 c k, o[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con . C4 T8 T s4 @$ Z8 i$ X6 v/ t) b+ ktrol of a physically simulated character. ACM T. Graphic. 27(5), 2008) g( ~9 H& `. A( T+ f K
y: `* c2 A1 W: E2 ^4 }' X; p2022. x: f8 u1 v5 O/ `
Certifificate Authority Cup International Mathematical Contest Modeling 3 k% m F, o6 O9 Qhttp://mcm.tzmcm.cn , C" r; w. U ^- {9 ZProblem D (ICM) ; L8 u& g+ G2 J }2 LWhether Wildlife Trade Should Be Banned for a Long ! c5 g( |# [6 C- }4 {. G, n$ MTime ; Z9 Q( V3 Y0 R' K0 w" V- X6 C% `' OWild-animal markets are the suspected origin of the current outbreak and the- P0 D+ y* o- X$ k& Y
2002 SARS outbreak, And eating wild meat is thought to have been a source/ l, Y" @# D) [3 c
of the Ebola virus in Africa. Chinas top law-making body has permanently* I; Z, }) f3 ]& p: a$ n& t
tightened rules on trading wildlife in the wake of the coronavirus outbreak,) s5 p* Z9 _. p' y7 R3 i# w- k6 h) M
which is thought to have originated in a wild-animal market in Wuhan. Some) G" e3 u: h4 |' W
scientists speculate that the emergency measure will be lifted once the outbreak 8 |) @' g0 E+ V! Q rends. ' m- h% A# K0 B3 _How the trade in wildlife products should be regulated in the long term? & @0 s8 `1 Z# l8 m3 ISome researchers want a total ban on wildlife trade, without exceptions, whereas* Z) O" l5 ^5 @4 Q
others say sustainable trade of some animals is possible and benefificial for peo9 G6 t5 [! ~; M! r- n9 {/ F$ B. F }
ple who rely on it for their livelihoods. Banning wild meat consumption could - z: X# M" }/ i0 }' h$ rcost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil + c; p, j5 [' [. T! S) k3 elion people out of a job, according to estimates from the non-profifit Society of 4 `8 L- m/ ]2 Y" N4 iEntrepreneurs and Ecology in Beijing., F& k/ ^5 J& I+ z( l
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology: t/ f1 v% W, Z: {! h1 d8 j# P
in China, chasing the origin of the deadly SARS virus, have fifinally found their : n& t" D. X0 K1 D5 C( \% r% Asmoking gun in 2017. In a remote cave in Yunnan province, virologists have! j' }2 r n" O" r* {
identifified a single population of horseshoe bats that harbours virus strains with 1 G. x: |$ I. v- Z" T& K9 X" a7 Mall the genetic building blocks of the one that jumped to humans in 2002, killing r; D0 ?1 T0 i: n" H5 V" g
almost 800 people around the world. The killer strain could easily have arisen + c8 k/ b1 Q% X' z/ xfrom such a bat population, the researchers report in PLoS Pathogens on 30 X$ J5 ` Y" b0 Q: X: z
November, 2017. Another outstanding question is how a virus from bats in 8 ?) a, D# f. mYunnan could travel to animals and humans around 1,000 kilometres away in 8 X# h( \$ v: O% ]Guangdong, without causing any suspected cases in Yunnan itself. Wildlife / e, f+ |* ~( [# V$ c# O& i$ u1 P" atrade is the answer. Although wild animals are cooked at high temperature ) n- q' R$ O6 ]- K' @; [3 y$ ?when eating, some viruses are diffiffifficult to survive, humans may come into contact 2 Z, W, M, S6 c" |- _with animal secretions in the wildlife market. They warn that the ingredients' h3 _5 L# \+ U6 J0 o( ?+ I9 D
are in place for a similar disease to emerge again.% L" c. i1 P: J5 T# U; t1 _5 o! M. ?
Wildlife trade has many negative effffects, with the most important ones being: . O9 R# d1 x t: n. c2 s1Figure 1: Masked palm civets sold in markets in China were linked to the SARS- I; G, K6 p& h% o
outbreak in 2002.Credit: Matthew Maran/NPL- z) V' U7 o# y8 H
• Decline and extinction of populations: u( P. ]; W7 ?& Y
• Introduction of invasive species6 ]' T; f0 q6 B* z
• Spread of new diseases to humans0 Y, @+ j5 s5 \* W$ n
We use the CITES trade database as source for my data. This database7 ?! r/ B+ B' @* _! J8 d
contains more than 20 million records of trade and is openly accessible. The+ ]/ ~# i' Q7 d# M: e! {* v
appendix is the data on mammal trade from 1990 to 2021, and the complete 7 P# g8 }: ]" } [5 K$ R2 ddatabase can also be obtained through the following link: J) |# h* m2 Z7 z+ Dhttps://caiyun.139.com/m/i?0F5CKACoDDpEJ - v' }, O3 r9 z- q! W) H5 e; iRequirements Your team are asked to build reasonable mathematical mod1 U) A2 w# A; Z7 l
els, analyze the data, and solve the following problems: , P! P" |& }; Y9 x* a1. Which wildlife groups and species are traded the most (in terms of live8 I7 W' i( l; ~2 J0 Q5 O/ B' |: i1 @1 D
animals taken from the wild)?5 ~, _6 I5 C ?6 Y
2. What are the main purposes for trade of these animals? ' u( J1 K9 |& _+ h' Z3. How has the trade changed over the past two decades (2003-2022)?; d, V7 i5 y. i! e: K3 e
4. Whether the wildlife trade is related to the epidemic situation of major # F, o0 y' ~& \$ dinfectious diseases? " y3 H( w5 n/ d1 t25. Do you agree with banning on wildlife trade for a long time? Whether it; W* a. J; i: I( U o/ f( G
will have a great impact on the economy and society, and why? + U. S8 Z4 o b1 q2 N& s0 Y6. Write a letter to the relevant departments of the US government to explain - S( f& u7 |# D6 c( \) Y6 ]your views and policy suggestions. A0 o/ r( z, R: L $ L" E$ m n$ i; x 9 l6 O' F% P5 H$ y, m z5 a g3 v& Q- y/ y* {: Q# a
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