2022小美赛赛题的移动云盘下载地址 ; E; e% p4 g0 o- rhttps://caiyun.139.com/m/i?0F5CJAMhGgSJx 7 Y7 R, n z, y' D7 d# t9 f2 }& |3 y. j$ b# N5 F
2022 2 e: B, s# y* P4 c% vCertifificate Authority Cup International Mathematical Contest Modeling / ^& W2 P5 ?$ T; N' khttp://mcm.tzmcm.cn 5 v2 `/ c- D2 O3 C: W! C' q P& IProblem A (MCM)" d" w. N( H) P% K2 J8 X& t
How Pterosaurs Fly$ X6 c/ k3 {* ^, R1 ]& a
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They ) h/ J2 I \" O5 P% lexisted during most of the Mesozoic: from the Late Triassic to the end of ) \* q- q* i# |2 ithe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved 8 Y: h' n; y! F$ opowered flflight. Their wings were formed by a membrane of skin, muscle, and* b& J! q( J+ j; F, J
other tissues stretching from the ankles to a dramatically lengthened fourth3 I: z G0 r( T& l& s; W
fifinger[1].1 ` K+ N9 z- t: t: U
There were two major types of pterosaurs. Basal pterosaurs were smaller * n+ U( a* J. P0 R, sanimals with fully toothed jaws and long tails usually. Their wide wing mem6 O5 P& w: z: m0 [
branes probably included and connected the hind legs. On the ground, they9 ]2 y/ [4 {' N
would have had an awkward sprawling posture, but their joint anatomy and4 Q7 h& k+ t2 U1 V$ R- e- t4 t U
strong claws would have made them effffective climbers, and they may have lived $ L; r& G5 m8 `6 T# gin trees. Basal pterosaurs were insectivores or predators of small vertebrates. " p) Q6 ]- [+ p6 s; BLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.% v$ E7 I- h- f
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails, # B# ]5 N) z3 g3 @and long necks with large heads. On the ground, pterodactyloids walked well on, v! M7 |9 x6 O1 \. d W0 v
all four limbs with an upright posture, standing plantigrade on the hind feet and# R5 a9 G( S) A/ W6 {9 o
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil , y/ z _4 y4 d( k8 @- c3 \trackways show at least some species were able to run and wade or swim[2]. : j+ X8 |4 g, y3 s9 a; s" XPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which & C, ?" n; L& B( zcovered their bodies and parts of their wings[3]. In life, pterosaurs would have 7 E! X# ^4 B9 S, hhad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug # ]5 u! ~' | O p& {* W1 Z- vgestions were that pterosaurs were largely cold-blooded gliding animals, de9 M8 i6 V1 c- N+ ?0 [
riving warmth from the environment like modern lizards, rather than burning# S& R6 @ y1 U! g$ l
calories. However, later studies have shown that they may be warm-blooded; G' Q! G+ y( S# i# K
(endothermic), active animals. The respiratory system had effiffifficient unidirec ' r0 R+ p% F2 T1 B9 utional “flflow-through” breathing using air sacs, which hollowed out their bones) [4 u1 Y* r) @; u% Q2 t: J
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from 5 @7 Y+ @/ `3 n) ^) i- q& r1 uthe very small anurognathids to the largest known flflying creatures, including7 ~8 B: d8 y& O
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least( H% F- Q0 J6 I' C, {
nine metres. The combination of endothermy, a good oxygen supply and strong , b& ?. @: B$ n: R$ z1muscles made pterosaurs powerful and capable flflyers.8 J) e5 h. K& ]1 H" T+ \/ i6 u
The mechanics of pterosaur flflight are not completely understood or modeled G h0 @/ Y; U0 o; g
at this time. Katsufumi Sato did calculations using modern birds and concluded+ |9 o0 K) ^! f/ |% P/ x( L
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,( O7 X4 z+ H5 X
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able9 _! W0 ~% U* P% F
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. * x1 z8 S0 b! C) G, fHowever, both Sato and the authors of Posture, Locomotion, and Paleoecology8 u0 a/ q p7 }3 E; i& g2 D
of Pterosaurs based their research on the now-outdated theories of pterosaurs : G4 `$ h) c" m# l: xbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, 2 Y4 @" U. ^$ v7 \: b" Lsuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that8 T. {3 h$ k4 M' w# O: U$ E
atmospheric difffferences between the present and the Mesozoic were not needed. Q" {9 j0 {& h- G' i2 ^5 v1 H% d
for the giant size of pterosaurs[8].* W; x2 j' y! V
Another issue that has been diffiffifficult to understand is how they took offff. , l3 J' ~/ D h- h! O: EIf pterosaurs were cold-blooded animals, it was unclear how the larger ones0 \: n9 ~7 ?. j3 n1 P9 G e7 V- H% P
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage + I0 W H! U( i, |, Ba bird-like takeoffff strategy, using only the hind limbs to generate thrust for % y2 l* l2 J7 t# H, T8 sgetting airborne. Later research shows them instead as being warm-blooded' J7 N) L! i. C9 Q( g% w: c8 N
and having powerful flflight muscles, and using the flflight muscles for walking as 8 T. f+ d0 A" y; v+ w+ Kquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of; i- z3 ^5 B i9 A! a* |( j
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism! J O2 S/ d% {
to obtain flflight[10]. The tremendous power of their winged forelimbs would5 a! v- `0 e7 H# D$ n+ m$ m7 h
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds/ J2 D, H2 |4 C' w
of up to 120 km/h and travel thousands of kilometres[10].* d7 ?% C: e/ y. u
Your team are asked to develop a reasonable mathematical model of the 0 i# Y& C% g. b* \9 _flflight process of at least one large pterosaur based on fossil measurements and * M- h7 o- a j5 E7 z: U- T. ^! Yto answer the following questions. " a/ B7 W: W B( Q# n0 b0 P. T1. For your selected pterosaur species, estimate its average speed during nor- s5 n/ |5 p- {; z' R4 X3 G1 F: S
mal flflight. : Y5 i/ G) Z% G6 @4 c/ @0 k) l# `2. For your selected pterosaur species, estimate its wing-flflap frequency during - s" @& V, ]( g" B' H' t4 anormal flflight.* h% V+ |0 \# }- y6 h. D% X
3. Study how large pterosaurs take offff; is it possible for them to take offff like # B# A. b' b! }/ Lbirds on flflat ground or on water? Explain the reasons quantitatively.2 X2 G6 c( P+ g1 c z# ?: Y/ o
References( H* ^$ O; H. B- h$ X$ h
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight2 S& M& W$ R: E! L' T/ I. m" Y
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111.( o: [7 C- H1 J6 ]- {9 {) E" {/ q
2[2] Mark Witton. Terrestrial Locomotion.! V# b2 i& O% ]6 j" p% H
https://pterosaur.net/terrestrial locomotion.php9 [2 L/ R, O' z0 ]. [' p% U
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs 0 f9 A( ~1 B ^ W/ SWere Covered in Fluffffy Feathers. https://www.livescience.com/64324- 9 V$ W% K) H7 B. c8 b2 t) X, Ypterosaurs-had-feathers.html; B+ U6 r: n: `) t1 n
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a1 z0 p, l1 j: ?8 g9 Y! W
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) , Y: j5 S: {& D, b/ V, Cfrom China. Proceedings of the National Academy of Sciences. 105 (6): - d4 m- _" [) G9 |1 O' Y1983-87.' W$ `7 w" g/ ]7 c9 m
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust! @$ y5 T7 E& v
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4): 0 R" m6 p4 }- m7 y" \9 f) t180-84. 5 n8 T S$ d! k/ ]8 l$ g& i" H[6] Devin Powell. Were pterosaurs too big to flfly? : o, s6 n9 M3 m- qhttps://www.newscientist.com/article/mg20026763-800-were-pterosaurs . P5 ]& m- k# V9 K( u! `3 Jtoo-big-to-flfly/ - a' z u0 {+ _1 U1 e[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology . d' X9 |/ Q2 u3 k5 iof pterosaurs. Boulder, Colo: Geological Society of America. p. 60.1 @3 `0 H8 g% [/ g( v, V$ o2 j
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable+ `9 A, `* j8 |7 O/ @$ H
air sacs in their wings. 8 F& s7 s0 a. B, A# lhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur L j- `$ S# r1 p! q" L2 ^$ N( U
breathing-air-sacs# b! H( \+ n4 @: D6 R d7 Z
[9] Mark Witton. Why pterosaurs weren’t so scary after all. + S* T. V1 K/ N _https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils + ~* ]3 b" x1 A; @# {8 ]research-mark-witton4 e) \, b1 Z# f$ k9 l
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 2 f; C- y/ ? thttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs 7 K, C# D# R1 W' j9 H; K3 ]0 Lvault-aloft-like-vampire-bats/ ; g! P8 L) w/ M2 E 3 P9 z0 X# L6 t! }$ Z. C2022 3 g0 o- t( z% r" I# q. RCertifificate Authority Cup International Mathematical Contest Modeling/ Z) T6 M4 Y4 h4 {& z2 W7 @& g
http://mcm.tzmcm.cn/ h) i, i3 M9 U+ h& Q
Problem B (MCM) 0 }( k# l( Y& i4 pThe Genetic Process of Sequences , H: T* H/ t E! N: I. ~) zSequence homology is the biological homology between DNA, RNA, or protein 4 o) K5 i0 f# X L9 Q' hsequences, defifined in terms of shared ancestry in the evolutionary history of( w S3 K+ J; Z& }/ N
life[1]. Homology among DNA, RNA, or proteins is typically inferred from their) Z3 N: S! P: i: J$ X! Y5 o8 C0 i9 i
nucleotide or amino acid sequence similarity. Signifificant similarity is strong1 w: ], e' |1 z8 O7 {# a3 J0 H6 d3 o: g
evidence that two sequences are related by evolutionary changes from a common ) B" d- U1 z4 A" uancestral sequence[2]. + q( K- X" }4 u4 vConsider the genetic process of a RNA sequence, in which mutations in nu( J" X+ Z) T" ~6 i2 F) m
cleotide bases occur by chance. For simplicity, we assume the sequence mutation - D/ k: D- C. v: _/ j/ N& Iarise due to the presence of change (transition or transversion), insertion and + v8 w2 _+ \9 F7 F8 kdeletion of a single base. So we can measure the distance of two sequences by3 T( m5 r+ n8 {4 v, F
the amount of mutation points. Multiple base sequences that are close together- K* V1 X+ X$ M. f) {4 U, [) s
can form a family, and they are considered homologous.8 x* l0 h+ k$ {: G8 n+ `7 ~$ n) t
Your team are asked to develop a reasonable mathematical model to com) K- i- z% L4 v9 j) J& ^
plete the following problems. ; e9 O0 F* e$ _6 L1 B1. Please design an algorithm that quickly measures the distance between. ` G7 B5 `- @2 o, q2 @! D
two suffiffifficiently long(> 103 bases) base sequences. 4 R( b) I \& Z7 i2. Please evaluate the complexity and accuracy of the algorithm reliably, and' g/ B+ `) n" X. b( N
design suitable examples to illustrate it. + G! _+ ~$ I) m6 J3. If multiple base sequences in a family have evolved from a common an% m: q8 j9 K* i& s
cestral sequence, design an effiffifficient algorithm to determine the ancestral$ h( D& A8 _! |5 I9 r4 F
sequence, and map the genealogical tree. . O' l* {0 \# P7 z0 n0 ]References K* Z1 K0 k2 J( D L: [
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re 4 |1 T2 ?0 F5 F5 f' ?view of Genetics. 39: 30938, 2005. ?8 N/ ?2 h; T( p# G' F[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, . Q; |2 _4 [. K q3 Yet al. “Homology” in proteins and nucleic acids: a terminology muddle and 5 ^2 g# r3 Y; R( ta way out of it. Cell. 50 (5): 667, 1987. ; C& z) Q5 |9 F) k: ~# {# ]2 g3 N) _5 w6 R& @4 l2 n5 d
20224 V4 U8 s/ n) f
Certifificate Authority Cup International Mathematical Contest Modeling" Q/ I! z7 a- U8 d. i
http://mcm.tzmcm.cn7 |1 M( F3 |1 W1 B1 m! [% m
Problem C (ICM)1 P" q- m3 I) Y# \! `' |) R- R3 W* z
Classify Human Activities # | ]( N2 e* Y6 rOne important aspect of human behavior understanding is the recognition and, e; D& c6 e0 G" [, v
monitoring of daily activities. A wearable activity recognition system can im 4 y: ^2 M0 }; {9 Z9 Eprove the quality of life in many critical areas, such as ambulatory monitor 2 M5 U: M0 {* R% g7 o9 Uing, home-based rehabilitation, and fall detection. Inertial sensor based activ ! t: S1 V6 F% \ S" Zity recognition systems are used in monitoring and observation of the elderly+ V6 ]' ]- x% P
remotely by personal alarm systems[1], detection and classifification of falls[2],3 t7 Z9 N) b# w! N. [/ ^
medical diagnosis and treatment[3], monitoring children remotely at home or in : S' u9 s# f6 w# q' S2 bschool, rehabilitation and physical therapy , biomechanics research, ergonomics,/ t8 E, a# f/ E) d
sports science, ballet and dance, animation, fifilm making, TV, live entertain * i0 C& r& \; L& I. oment, virtual reality, and computer games[4]. We try to use miniature inertial2 O4 x) p2 G( u! f
sensors and magnetometers positioned on difffferent parts of the body to classify . }) I$ ^5 u1 }5 Z9 Xhuman activities, the following data were obtained. + u( I0 t z0 u+ j& _1 PEach of the 19 activities is performed by eight subjects (4 female, 4 male, ) k4 _; H; O; {# @* d. B6 s5 `" x) Q! cbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes, Y8 }5 P/ a" _. A! |- r& P! G
for each activity of each subject. The subjects are asked to perform the activ4 w% H5 {8 B( z( r; E! J
ities in their own style and were not restricted on how the activities should be - H: E2 M$ r6 O/ P4 nperformed. For this reason, there are inter-subject variations in the speeds and 5 o& B; J4 y3 j1 damplitudes of some activities.1 z' f1 z2 W% M* [# f2 [' d
Sensor units are calibrated to acquire data at 25 Hz sampling frequency.& F$ h3 H' n. J3 ~8 u
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal+ A% H3 T6 L# V: d
segments are obtained for each activity. ( c! Y- a% b8 Q8 z; sThe 19 activities are: 1 `2 z5 s3 |% K6 c. @- f- Q. p1. Sitting (A1); 6 d9 s" h5 N! g `; K; M6 q2. Standing (A2); V! j; N; p, ^/ J! `
3. Lying on back (A3);5 H7 N1 H/ C! s; B
4. Lying on right side (A4);! B# I9 g8 V' r2 `% K6 K
5. Ascending stairs (A5); - E- |7 }, f3 I9 x0 L* r. |16. Descending stairs (A6); 7 b D' C8 w7 e$ x8 y% P0 O# l( M* L0 J7. Standing in an elevator still (A7); ! o" l0 c8 Y# H: h0 ^ q8. Moving around in an elevator (A8);. N/ q. V$ w8 Z& Q
9. Walking in a parking lot (A9);9 f3 s# [4 b/ U9 N B
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg 0 H+ F& i' Q" f% q0 cinclined positions (A10); 6 w3 g- F1 i: X, _8 H. N5 J) k11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions# H W4 v; R( y
(A11); 4 E1 G4 U# R2 E- ^8 k* _: ?% F12. Running on a treadmill with a speed of 8 km/h (A12); & j9 q& R$ H" x/ A/ ]13. Exercising on a stepper (A13);9 A! _1 e4 p7 Z% N6 S' l
14. Exercising on a cross trainer (A14); . M# {7 G$ n( {1 {& l" v9 t. _) K15. Cycling on an exercise bike in horizontal position (A15); 9 X; `9 e$ o% F16. Cycling on an exercise bike in vertical position (A16);9 C( E# f) D" J" W+ k$ @5 X
17. Rowing (A17); 6 w' G" d; B/ g/ h$ ?18. Jumping (A18);$ N0 A( _0 _- m: {
19. Playing basketball (A19). 5 T1 W9 {2 v2 mYour team are asked to develop a reasonable mathematical model to solve: _! |+ O3 {0 f# O* v6 H
the following problems.1 P2 O: `: e+ m
1. Please design a set of features and an effiffifficient algorithm in order to classify" a/ d8 K# T4 @* i0 O( A" J
the 19 types of human actions from the data of these body-worn sensors. 2 a! r' I! K! [; c; ]2. Because of the high cost of the data, we need to make the model have, @1 i/ z5 k: z+ f. _! y I
a good generalization ability with a limited data set. We need to study0 L2 I) P0 F* j4 Q
and evaluate this problem specififically. Please design a feasible method to 1 [; F: t* k5 d2 c7 w9 a1 h. n3 Tevaluate the generalization ability of your model.8 r: d% i6 Y1 h& }$ n
3. Please study and overcome the overfifitting problem so that your classififi- 7 s, q- Y t4 acation algorithm can be widely used on the problem of people’s action 9 E, ~& a- G! L/ k9 w: ]classifification.! D+ R" Q* S4 w7 m9 }0 L, E) E5 D
The complete data can be downloaded through the following link: ; ~: h0 T1 o% T5 t! uhttps://caiyun.139.com/m/i?0F5CJUOrpy8oq 4 W9 @$ H: j' t1 u- Y' F2Appendix: File structure2 e( v, Z1 ^5 `1 T
• 19 activities (a) . F* x9 C) G2 F8 E• 8 subjects (p)$ w" E6 P) D% _1 e# A& Z% u
• 60 segments (s) & K. j$ \# G( M, t: U* a• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left, Q, q9 e E, o' _8 q
leg (LL)6 ]5 @/ V w5 @* s
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z z2 r& L9 w( _$ c |magnetometers)$ \: g" _4 d9 t
Folders a01, a02, ..., a19 contain data recorded from the 19 activities. - m& s* t+ F% \' }0 P: S' y+ w) UFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the9 F3 E% N/ |, S
8 subjects.( A0 o$ G, I. y- U3 b& _0 f) Y
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each 2 I! B' q6 [3 W- d. csegment. 5 p( ~" t1 D" N4 g! X0 TIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 ' v/ t. f/ `- F& M) BHz = 125 rows.( T* @) k& F( M
Each column contains the 125 samples of data acquired from one of the $ c3 g( H4 ?8 z; A7 \1 o8 j$ bsensors of one of the units over a period of 5 sec.4 F0 |& y. r5 {" g
Each row contains data acquired from all of the 45 sensor axes at a particular0 ?1 Z& Z9 N* u- v
sampling instant separated by commas.: [% K$ A: ^. I
Columns 1-45 correspond to: 0 @/ ^% Z0 m2 l& F7 s) A7 ]• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, 6 X$ j, q+ e& b; Q% e• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, 0 k: ?1 ~' d1 u• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, $ l( H4 R$ z$ R0 U( p3 E3 S• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, 4 B$ Z2 C: b& ^4 \8 r• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. 9 d/ N% M9 m" h* J# t; QTherefore,! {, j6 I' a/ |6 D3 m/ i3 g
• columns 1-9 correspond to the sensors in unit 1 (T), - b4 b# s4 H( S/ u) K• columns 10-18 correspond to the sensors in unit 2 (RA),5 o8 }1 p( n) j, j
• columns 19-27 correspond to the sensors in unit 3 (LA), . b N) t$ j2 c/ |& y) D+ Q9 W! f• columns 28-36 correspond to the sensors in unit 4 (RL),! t+ k# g5 I4 D0 S1 H5 p
• columns 37-45 correspond to the sensors in unit 5 (LL). 2 a) V, y- }9 a3References- f4 a1 q, Z/ ^" H( Y& x' @
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic , S5 G" F; ]+ U0 C3 _daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. 1 M- }1 \. y$ N) @42(5), 679-687, 20041 E: b! y2 V5 H# N* k4 i
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of 1 w% G8 ^# W1 j1 e2 e s5 E% \low-complexity fall detection algorithms for body attached accelerometers. 5 P9 |. ~9 T* f* UGait Posture 28(2), 285-291, 2008% c m6 G2 ~/ q% y3 |
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag ( [" ~9 G3 y }- R9 o% t7 s+ y$ nnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. , Z: A" w" ^3 V) V, U/ X1 Y, xB. 11(5), 553-562, 2007 - b* A! N* x6 h! o0 ]- g0 s- i[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con 8 u& T; Y0 C/ u3 q0 j% Y8 ctrol of a physically simulated character. ACM T. Graphic. 27(5), 2008 . g5 L! M0 x, @3 S `9 n ( a- g( }& x) P" ~+ T; V) O; v. C2022 + m! y9 r" F8 o' hCertifificate Authority Cup International Mathematical Contest Modeling ) N: s( K- X: f" r) Z+ \http://mcm.tzmcm.cn " @' ]+ z0 l/ q: f. \/ A8 x; qProblem D (ICM)7 y( [, Z `# g7 _6 j7 v( D
Whether Wildlife Trade Should Be Banned for a Long # p, `) I; o, T# ATime ! t' L x6 D' Z& z/ EWild-animal markets are the suspected origin of the current outbreak and the6 B/ U$ ]8 j. Y* |$ y7 M0 H7 j
2002 SARS outbreak, And eating wild meat is thought to have been a source8 [5 ]# U' j( Y L# v1 Z# v2 K) {4 n
of the Ebola virus in Africa. Chinas top law-making body has permanently ! X0 ~3 ?% a; Atightened rules on trading wildlife in the wake of the coronavirus outbreak, u u6 \( @- t6 S, p+ |which is thought to have originated in a wild-animal market in Wuhan. Some - v* {+ b. W1 {& @* y, p; pscientists speculate that the emergency measure will be lifted once the outbreak 4 c, z0 ^5 V Y% ?ends.1 S/ P) p/ y8 g' ~2 ?5 V2 h
How the trade in wildlife products should be regulated in the long term? / b) N! N2 B) B6 MSome researchers want a total ban on wildlife trade, without exceptions, whereas 7 }7 K* N" C3 y0 rothers say sustainable trade of some animals is possible and benefificial for peo ' V% x- J- J. I" g4 U( \ple who rely on it for their livelihoods. Banning wild meat consumption could 4 w% `" c. f+ [; qcost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil+ B/ X1 s1 J8 `- c, e$ P& X
lion people out of a job, according to estimates from the non-profifit Society of & b- O3 w' V; g# ]; v, _Entrepreneurs and Ecology in Beijing. 0 B; @8 r* B* iA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology ; a& t* Q! p# S4 din China, chasing the origin of the deadly SARS virus, have fifinally found their $ G% Q! ~# b7 G/ r, ?smoking gun in 2017. In a remote cave in Yunnan province, virologists have . O/ C) s6 t3 I5 y8 Oidentifified a single population of horseshoe bats that harbours virus strains with: C4 ^) D- \ y& Y
all the genetic building blocks of the one that jumped to humans in 2002, killing & Y1 H* Q' i- e* p* e, U! Zalmost 800 people around the world. The killer strain could easily have arisen A3 r+ l/ e) p }3 s0 e1 @* T4 ~
from such a bat population, the researchers report in PLoS Pathogens on 30 ! v- C6 W$ Z3 D- d: KNovember, 2017. Another outstanding question is how a virus from bats in& T% Q, l. F5 Z( a# s8 w2 t1 D
Yunnan could travel to animals and humans around 1,000 kilometres away in ; {' a! S/ |6 @$ c" i: c2 kGuangdong, without causing any suspected cases in Yunnan itself. Wildlife! ?8 p% ^# s1 N% }1 r0 W0 y
trade is the answer. Although wild animals are cooked at high temperature 5 f' A# G5 t8 `4 g7 wwhen eating, some viruses are diffiffifficult to survive, humans may come into contact ' z( k* h, H9 \- f R% J4 G, |, {, Kwith animal secretions in the wildlife market. They warn that the ingredients 8 Q1 L8 ]! s* y. G* Qare in place for a similar disease to emerge again.! ?9 K: W* R5 E3 n7 I# t ]
Wildlife trade has many negative effffects, with the most important ones being: 8 m* A' m+ M* Q9 A) _8 D1Figure 1: Masked palm civets sold in markets in China were linked to the SARS6 Y8 f# a1 A5 s& E, r
outbreak in 2002.Credit: Matthew Maran/NPL ' w, c0 F9 ~7 ~8 V' v6 @) T* M• Decline and extinction of populations 3 N& K+ n" R2 D4 D3 o: W• Introduction of invasive species ! x: I; z/ _* e( ?, U; ?# h• Spread of new diseases to humans 5 i" O2 w: e2 } l/ [3 z: I6 yWe use the CITES trade database as source for my data. This database $ O9 c, W" ?% E/ N- j, Vcontains more than 20 million records of trade and is openly accessible. The. R# n' {4 l7 Z5 h9 R- V! ^
appendix is the data on mammal trade from 1990 to 2021, and the complete % X' h) b# P+ g8 H0 Ldatabase can also be obtained through the following link:+ b+ F1 G8 R0 ~& L) N: I; c
https://caiyun.139.com/m/i?0F5CKACoDDpEJ/ e$ [- _. F# |2 ]
Requirements Your team are asked to build reasonable mathematical mod3 \& e5 l j! K p8 b; o
els, analyze the data, and solve the following problems:7 p& w9 [+ O# ^ X- X
1. Which wildlife groups and species are traded the most (in terms of live o7 e, i2 u( `7 Q9 [! S
animals taken from the wild)? - |0 m8 ?$ f8 u2. What are the main purposes for trade of these animals? 4 k6 T- @$ k# E; j$ C; C3. How has the trade changed over the past two decades (2003-2022)?8 z; Q5 S- k6 u0 w& s' o
4. Whether the wildlife trade is related to the epidemic situation of major . h' _7 }: v" R. M' X1 S6 g' cinfectious diseases?8 S6 _2 K/ s1 ~7 P8 b7 B6 S3 `
25. Do you agree with banning on wildlife trade for a long time? Whether it5 r& x2 Z c. p
will have a great impact on the economy and society, and why?$ ]7 ^" ?3 X/ X* P( \
6. Write a letter to the relevant departments of the US government to explain1 B; e4 w6 m. u. P! _
your views and policy suggestions.9 L- D3 s+ p# I( p$ @
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