2022小美赛赛题的移动云盘下载地址 7 o5 Y! k6 g+ M' L" n0 o# Ihttps://caiyun.139.com/m/i?0F5CJAMhGgSJx : t5 A% ~) M$ {; d( u( R/ i: r, G3 _4 j$ Q
2022 I# z# ~3 t# z l' H! B
Certifificate Authority Cup International Mathematical Contest Modeling 8 g# c: S1 p8 xhttp://mcm.tzmcm.cn1 L$ w4 ^8 G" |3 K8 I+ k
Problem A (MCM)% {# @7 i* C( G6 J+ |5 g, G& D; C
How Pterosaurs Fly / u3 O! d6 C# h* ^Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They/ J, K3 F/ H9 b& t' o' M
existed during most of the Mesozoic: from the Late Triassic to the end of) N% J; E5 c, M$ X) t2 ~9 w" U
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved, _" ~) j; U! C1 [' r1 F3 G. x0 ]
powered flflight. Their wings were formed by a membrane of skin, muscle, and 5 U& n% J7 A: h. W0 Eother tissues stretching from the ankles to a dramatically lengthened fourth+ A- s# H, N: x/ _: H
fifinger[1]. |. |% c" _8 K9 z FThere were two major types of pterosaurs. Basal pterosaurs were smaller% E7 _3 I2 O0 r j
animals with fully toothed jaws and long tails usually. Their wide wing mem 6 \+ O& m) G/ ibranes probably included and connected the hind legs. On the ground, they! J# m9 p3 z [7 E, h. o
would have had an awkward sprawling posture, but their joint anatomy and9 D9 B6 M9 {- K; k
strong claws would have made them effffective climbers, and they may have lived 6 d4 f3 V: A8 Q& z9 ein trees. Basal pterosaurs were insectivores or predators of small vertebrates. 9 K+ S1 x& M3 J: ZLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. , q" ^0 S0 ~: k2 d0 r4 [; E5 mPterodactyloids had narrower wings with free hind limbs, highly reduced tails, 1 w5 s8 k+ _! fand long necks with large heads. On the ground, pterodactyloids walked well on4 o- R+ h" b6 H
all four limbs with an upright posture, standing plantigrade on the hind feet and . X) B) z! P5 }. n% Tfolding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil 5 o9 k6 c5 M5 M) Xtrackways show at least some species were able to run and wade or swim[2].. t) J: l h. M) Z) ?' Y: ?% K! D
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which. B3 M7 D( T/ b( C2 i0 L6 E. T4 @
covered their bodies and parts of their wings[3]. In life, pterosaurs would have $ K. _( a; [& A. fhad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug 3 u; U$ m3 Q) x d! z: p' Bgestions were that pterosaurs were largely cold-blooded gliding animals, de ; g2 O9 I, N4 kriving warmth from the environment like modern lizards, rather than burning& s! ^/ b: e) ^0 p, K2 c
calories. However, later studies have shown that they may be warm-blooded # O' v7 F, L0 C5 b9 }(endothermic), active animals. The respiratory system had effiffifficient unidirec2 m/ G$ H( i* w# M1 x! j
tional “flflow-through” breathing using air sacs, which hollowed out their bones . P6 I& y7 H, r. D( b q- Bto an extreme extent. Pterosaurs spanned a wide range of adult sizes, from ) W8 h W6 }& b5 E% ^2 ^the very small anurognathids to the largest known flflying creatures, including ! v0 h7 g' }5 s; ^3 v8 IQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least, G5 y6 A( {) n7 b1 Z
nine metres. The combination of endothermy, a good oxygen supply and strong 5 c' K* }% t6 Y1muscles made pterosaurs powerful and capable flflyers. ! x: M- _$ Y5 [5 k1 D- dThe mechanics of pterosaur flflight are not completely understood or modeled+ v" d$ [5 ~& M$ ?9 H
at this time. Katsufumi Sato did calculations using modern birds and concluded. [4 Z8 p2 F6 }% L
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture, 5 S" x) S5 q) T& |+ v7 v+ t4 V( R" lLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able : b3 [4 I) d+ R O9 _* ]7 Kto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. 4 H4 b* T) h7 q5 c0 nHowever, both Sato and the authors of Posture, Locomotion, and Paleoecology : ^" y* d. x, [8 Sof Pterosaurs based their research on the now-outdated theories of pterosaurs7 L% W! d( ^# T4 @$ F4 F2 g
being seabird-like, and the size limit does not apply to terrestrial pterosaurs, : Y, F3 k4 f8 V3 p& csuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that4 g9 e& S- ]9 \8 q& s
atmospheric difffferences between the present and the Mesozoic were not needed' U6 z& c, i! y
for the giant size of pterosaurs[8]. 9 w$ r- q/ h! Y3 x* k8 x" e% S4 h& FAnother issue that has been diffiffifficult to understand is how they took offff. 6 l8 u! ^2 v3 A$ e/ [2 ^5 r) [8 y. ^If pterosaurs were cold-blooded animals, it was unclear how the larger ones; ^! P( _: ~" w) L+ i v% Q) E( t
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage8 U' T* k3 o' M' q
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for. a& E6 J" I" v' }! v* \3 e7 f
getting airborne. Later research shows them instead as being warm-blooded& k1 n) @8 H& [3 [
and having powerful flflight muscles, and using the flflight muscles for walking as S7 x; ^; a) p8 U8 f% Xquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of S( s- O$ |8 d; AJohns Hopkins University suggested that pterosaurs used a vaulting mechanism + {9 w$ n* o$ Q* }$ v- V* Ito obtain flflight[10]. The tremendous power of their winged forelimbs would E% P% C0 ~; [3 a+ G g4 N
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds , ?0 L' ?% ^4 N2 e, P$ Pof up to 120 km/h and travel thousands of kilometres[10]. : v5 d' E5 n. F7 ]Your team are asked to develop a reasonable mathematical model of the + h# O: b( x! z" T: B% |2 jflflight process of at least one large pterosaur based on fossil measurements and$ e; K" J5 i) E( U
to answer the following questions.1 k9 O7 \$ i. g3 V
1. For your selected pterosaur species, estimate its average speed during nor * `' O) m, Y# e2 Gmal flflight. 7 J- f) j8 M. o$ o, z3 E2. For your selected pterosaur species, estimate its wing-flflap frequency during 6 g; a7 E3 T- W; g: s" [. \normal flflight. : p1 O0 P T1 K) f# U) m% p0 z$ M; Z3. Study how large pterosaurs take offff; is it possible for them to take offff like & V* ?* Q; v% s* K$ y+ Kbirds on flflat ground or on water? Explain the reasons quantitatively. 9 Y% F4 I9 }0 ]References3 i7 g' Z, `$ ~9 E: y" v4 Q( t/ ]
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight # U0 m: Y% [0 l& S! z9 SMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111.1 S! Z4 B0 J# J7 F6 _) \* E
2[2] Mark Witton. Terrestrial Locomotion.$ I+ a# h+ \0 q# z# ?/ H' u7 S0 T/ b. `
https://pterosaur.net/terrestrial locomotion.php8 t. o% @3 \% y6 M
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs& E& `' g Y+ u& X# C, Y
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324-, g& F1 n& V1 X2 E2 Z
pterosaurs-had-feathers.html ) S) S9 z) p# @$ U' f& i. Q, M[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a. \' Q) D8 [0 i( _& Q+ G
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)% o* O, O' E% b
from China. Proceedings of the National Academy of Sciences. 105 (6):9 p8 Z% v1 H/ Z1 q; W% e
1983-87., y% O! \* Z \6 a+ O
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust ) B! ]4 i/ F" Fskull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4): , [! a0 j9 e3 E180-84.* h( h" c& M( K7 w1 ~9 L6 M( Q
[6] Devin Powell. Were pterosaurs too big to flfly? . f. o7 i/ r) |8 M" q+ k, q( X0 @https://www.newscientist.com/article/mg20026763-800-were-pterosaurs% D% C9 L6 H4 J0 f. |
too-big-to-flfly/ 3 [9 C& P$ o: a& A[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology5 D3 t' P& V" u% Z% O; d C/ g! ~
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. 8 D( J& A- d. D t4 i! f/ z" {[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable 3 A# n0 C- w9 o# }! k+ \0 oair sacs in their wings.2 [ w( e! n( ?2 }
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur h8 u8 C) g4 D& ?
breathing-air-sacs0 L- l7 ~ m. q& f4 }
[9] Mark Witton. Why pterosaurs weren’t so scary after all. & x4 g) i, E7 |' rhttps://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils ; U( N. i9 f/ G d0 Dresearch-mark-witton: D- v6 C2 B; f$ r! S
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 2 A) O" x# I/ a2 h1 Y) mhttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs ' E9 [/ }/ m; X; ]$ cvault-aloft-like-vampire-bats/ # H* L" v& p- `( J+ ?% z# A. s4 D: v6 W
2022. b/ e4 r+ Y* q. Q+ s! B
Certifificate Authority Cup International Mathematical Contest Modeling 7 y- Q/ K! D* j0 @- b. fhttp://mcm.tzmcm.cn ; F9 |3 S* ]$ b) Q" `" G$ |Problem B (MCM) + h9 T2 t0 l" |7 D. s# Y& P4 ~The Genetic Process of Sequences & J6 G4 x; ^) r* B# dSequence homology is the biological homology between DNA, RNA, or protein P" x5 c2 [5 i
sequences, defifined in terms of shared ancestry in the evolutionary history of - L5 V* p# H f% Olife[1]. Homology among DNA, RNA, or proteins is typically inferred from their 5 Z/ h! U% K `% u% znucleotide or amino acid sequence similarity. Signifificant similarity is strong; f' d* f. o" {4 i1 k
evidence that two sequences are related by evolutionary changes from a common' s/ G5 w5 G1 Q9 Z9 F& [
ancestral sequence[2]. 6 Y9 T9 D" Z J/ VConsider the genetic process of a RNA sequence, in which mutations in nu 0 x$ b, X ?( h U- ?- Ncleotide bases occur by chance. For simplicity, we assume the sequence mutation% A: C6 d' E2 j0 b# R
arise due to the presence of change (transition or transversion), insertion and+ x z$ C3 ]* E9 M9 @
deletion of a single base. So we can measure the distance of two sequences by ) q# x8 s8 v$ C0 G9 E" G2 k' Gthe amount of mutation points. Multiple base sequences that are close together . {7 R: _$ ?% l7 B7 Zcan form a family, and they are considered homologous. 1 P4 C' D; M; `4 _( R+ ]% f( m9 oYour team are asked to develop a reasonable mathematical model to com* e% X) b4 i3 ]9 G$ b( _! V/ v6 s8 j1 }1 L
plete the following problems. & K8 p% R0 _" p: k$ }1 H8 `" E j# u1. Please design an algorithm that quickly measures the distance between 3 X8 X0 y0 M: Wtwo suffiffifficiently long(> 103 bases) base sequences.9 P f O! I Z( H/ y2 r+ I7 F
2. Please evaluate the complexity and accuracy of the algorithm reliably, and- a) r$ G: G/ `
design suitable examples to illustrate it. ! J8 F8 ~5 y4 p2 j) v1 d3 T3. If multiple base sequences in a family have evolved from a common an: o; N- w( v! D! G# [" Q$ N
cestral sequence, design an effiffifficient algorithm to determine the ancestral4 V, h: O2 H5 E& H% l7 ]/ h
sequence, and map the genealogical tree. + s q5 n+ {+ i, c& m+ |8 W& j$ mReferences - F D, \: |6 m! b6 n0 u% {9 }( ~; U6 H[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re 1 A; [# L, l' a* ?2 g6 Dview of Genetics. 39: 30938, 2005.. t. x4 _/ w, X7 Y% }: Q
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, l! |: }5 E9 s' o
et al. “Homology” in proteins and nucleic acids: a terminology muddle and2 c0 m a: Y$ B, ~5 _
a way out of it. Cell. 50 (5): 667, 1987.* o- f" l9 w' w& h% z: C
" p" s) i8 h n- a5 r2022( w, V2 u- L* i
Certifificate Authority Cup International Mathematical Contest Modeling - j( u9 J6 ~: `http://mcm.tzmcm.cn ) f+ w7 b& ]5 TProblem C (ICM)8 l, h: P/ f) ^
Classify Human Activities 8 J9 O( E" l# D* z; QOne important aspect of human behavior understanding is the recognition and( u6 P7 U' }/ x$ _$ R0 W! B6 h
monitoring of daily activities. A wearable activity recognition system can im 6 {6 E6 k* V, H, Xprove the quality of life in many critical areas, such as ambulatory monitor' X* ^+ W0 G9 ~# }4 Z8 j6 X7 ] M
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ, l, z8 R# W3 |* E
ity recognition systems are used in monitoring and observation of the elderly; O- X3 R0 u/ h* E S9 W" e1 `' D
remotely by personal alarm systems[1], detection and classifification of falls[2],. T- n$ h0 @- G% P( w
medical diagnosis and treatment[3], monitoring children remotely at home or in 8 g7 K. F, r* w8 j$ z: ]school, rehabilitation and physical therapy , biomechanics research, ergonomics, . T2 y, x7 R+ a- `7 S4 H% Q0 usports science, ballet and dance, animation, fifilm making, TV, live entertain ( U9 k" X# X9 u4 }/ rment, virtual reality, and computer games[4]. We try to use miniature inertial , ^% f( x/ w6 S. K/ ?sensors and magnetometers positioned on difffferent parts of the body to classify# N+ F3 m; w/ X
human activities, the following data were obtained. . D9 O5 [* ^7 I7 a' ]Each of the 19 activities is performed by eight subjects (4 female, 4 male, $ ~" C& v4 d O" |5 Tbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes 6 ~5 L5 V: `- Y/ [for each activity of each subject. The subjects are asked to perform the activ& z A* H* L! N+ ]
ities in their own style and were not restricted on how the activities should be" L, L) h" L+ w0 t# u5 Y1 S( {
performed. For this reason, there are inter-subject variations in the speeds and, o& b9 ?- ^+ r+ `/ g9 b3 p' B) K4 S
amplitudes of some activities.! W1 h6 m! ^ c2 {/ k b# E
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. + N. t8 i% C8 c1 V% iThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal 5 N; E9 F/ z/ xsegments are obtained for each activity. . |, U0 T/ F9 g6 p' x# A+ ]The 19 activities are:0 G6 d# I, X" _' D& r
1. Sitting (A1); " v1 R# k" P6 g( E- H' P% g* x2. Standing (A2);5 R( l2 g# U0 ~/ y2 n. C2 k
3. Lying on back (A3); $ [' p7 N- i9 ^3 R) r9 l( {/ p4. Lying on right side (A4); $ f1 Y" y) @2 i; ~; `1 W; L5. Ascending stairs (A5);. i: n. u: f N- ?( O
16. Descending stairs (A6); , Y$ m; E4 F1 \8 {. D9 ?: |7 Z7. Standing in an elevator still (A7);! Q6 A1 R$ k+ U3 {. d
8. Moving around in an elevator (A8);$ G7 v) z8 w1 R' A# h1 v a9 i
9. Walking in a parking lot (A9);4 k9 ~( v2 |: R8 j7 o! v
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg0 S1 V: O5 U6 C4 y1 Q
inclined positions (A10);. V6 V) @* ]8 s: }
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions 2 ~( l. `( Z/ }(A11);! H, ~! G4 q) r" l# a0 c( X
12. Running on a treadmill with a speed of 8 km/h (A12); + p' R% b8 n: Z: C5 m! o8 m13. Exercising on a stepper (A13);2 d' {" l4 {2 h" Y/ c
14. Exercising on a cross trainer (A14); % ]1 w" N0 h0 e0 \& h9 i15. Cycling on an exercise bike in horizontal position (A15);; e1 H! f* ~0 K
16. Cycling on an exercise bike in vertical position (A16); - M; ?; {1 P9 B# s5 t; i, p- E* _17. Rowing (A17); 2 T2 n" S6 u- S- D* l2 @6 z, n18. Jumping (A18);: v2 o- v; j5 V1 ^
19. Playing basketball (A19). 1 r+ Z" @# a0 \/ }" yYour team are asked to develop a reasonable mathematical model to solve 9 o$ Y% O0 |$ Z, cthe following problems. & ~* M/ S# U, a2 r! i1. Please design a set of features and an effiffifficient algorithm in order to classify ' x% H0 A: ?# U8 t d) kthe 19 types of human actions from the data of these body-worn sensors. / W8 p# f, e3 K: |( d! O. O2. Because of the high cost of the data, we need to make the model have r/ X$ z: b8 f: y7 o
a good generalization ability with a limited data set. We need to study 0 U+ t+ B' G- E1 |* g( n4 I2 {. Gand evaluate this problem specififically. Please design a feasible method to % g! O# W. ]0 c) E y/ c2 f$ p; ^evaluate the generalization ability of your model.7 R7 c9 r1 m" {! ]7 c. l g
3. Please study and overcome the overfifitting problem so that your classififi-) g9 u; Z! G( U; H( q1 a
cation algorithm can be widely used on the problem of people’s action ' ~- [$ \7 Y2 W& uclassifification., x) k5 x# ^ Z& `( l% P+ a
The complete data can be downloaded through the following link:- s) e9 r- U- t
https://caiyun.139.com/m/i?0F5CJUOrpy8oq # Y; Q6 x# n5 G2Appendix: File structure 1 c+ U+ N" U1 H+ o' n1 Y• 19 activities (a) - h! c5 _$ k/ r3 c: _. L• 8 subjects (p) & @2 E9 [- m& X# K# P1 ^• 60 segments (s) a2 i9 e0 { P$ N' K• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left u3 H0 x! _# u j8 X3 O5 C- L9 O* hleg (LL) ! E9 W2 V# d; G0 G$ o( |- \" q1 H( c! O• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z : \, P0 a- n0 R- emagnetometers)! {! W( n4 ?' T
Folders a01, a02, ..., a19 contain data recorded from the 19 activities.4 t# e( \$ s& \" _* k3 l! B
For each activity, the subfolders p1, p2, ..., p8 contain data from each of the% e7 I9 I+ ?- y+ H
8 subjects.* A- D3 }4 M% l( T
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each $ @2 n( m. K5 X- w# w4 ssegment. % f( O. \$ n9 r% w0 l4 f* K2 \In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25, r& G8 }7 P* {
Hz = 125 rows. : L2 t7 c' W, d! m: ZEach column contains the 125 samples of data acquired from one of the # X. H6 h0 z9 ?" r' U, ^* j; A3 vsensors of one of the units over a period of 5 sec.: B* X% ]2 H) |7 f6 X a7 z" G
Each row contains data acquired from all of the 45 sensor axes at a particular; E+ H7 @9 S% o# D6 q* a! ?7 G' Y
sampling instant separated by commas. : n% s& y0 D0 |Columns 1-45 correspond to: 1 C/ [% }; u; R7 R* w) { l• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,) H' ~- M9 E& j. X9 H$ v) I* `# I' `/ Z
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, ! a+ y& p x4 r3 }7 o• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, ( R: l/ |$ o, ?: M9 j: o4 |• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, 4 l9 l9 T9 R9 {, _% @% G. C* o• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. ' d8 I" l+ y$ G8 x6 T7 M, N) ITherefore,+ u$ L$ E8 y5 ?% G: ~* m
• columns 1-9 correspond to the sensors in unit 1 (T), 0 d0 b, C2 k7 a' g7 U K5 r2 r• columns 10-18 correspond to the sensors in unit 2 (RA)," \" |7 c; M1 }% n) q7 A6 l& }
• columns 19-27 correspond to the sensors in unit 3 (LA),, X% z8 j: T/ T
• columns 28-36 correspond to the sensors in unit 4 (RL), ) c! g2 c4 @% g• columns 37-45 correspond to the sensors in unit 5 (LL). 6 A/ B# R1 X; w7 `4 S! j3References& u+ ^7 z, A, a" X7 a1 E! B
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic # G. z/ W+ Y+ q6 sdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. 8 D" e& x+ J2 M+ I2 e! M42(5), 679-687, 20045 D: G, j. W! b* ]7 y
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of - c% Q4 L$ Z4 U$ C6 y) f) _" a4 ?low-complexity fall detection algorithms for body attached accelerometers. , g0 W: r2 | W1 U E9 ^Gait Posture 28(2), 285-291, 2008- Z, a+ |$ I- \/ J, ]1 ?. e. D ^
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag/ d$ ^. Z1 x1 E* V( x
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.. ?( m2 Z! v, q2 J/ x' X
B. 11(5), 553-562, 2007% p! B: a1 Z. j. c" u2 p/ W
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con8 O: O' o5 m9 f# ~( T5 R" R1 F
trol of a physically simulated character. ACM T. Graphic. 27(5), 2008 " y8 `9 p- \" T' t/ m 2 g5 J! G8 S: @2 \6 L2022 7 _1 Z$ q7 n# u( ^% L6 KCertifificate Authority Cup International Mathematical Contest Modeling+ C9 n& L- e: b- i
http://mcm.tzmcm.cn , i1 }$ w8 c! K- }& \/ sProblem D (ICM)% L, j- V& h; a. M. y: L4 S
Whether Wildlife Trade Should Be Banned for a Long , m# n! t4 v2 t# kTime" H/ y8 E/ N. m* R# S
Wild-animal markets are the suspected origin of the current outbreak and the ; ~& ^6 ^' Y3 Q7 S9 X E2002 SARS outbreak, And eating wild meat is thought to have been a source 7 a% e4 }' ^- O$ `8 zof the Ebola virus in Africa. Chinas top law-making body has permanently* W8 l; F, g( m& Q9 B' t
tightened rules on trading wildlife in the wake of the coronavirus outbreak, ( |4 ?- t- a; a R6 ]* Qwhich is thought to have originated in a wild-animal market in Wuhan. Some 7 M. m5 G$ w, X# }scientists speculate that the emergency measure will be lifted once the outbreak : {* L' M+ b! [6 {ends. 3 _7 A, ]7 M5 w9 H0 ]7 i- MHow the trade in wildlife products should be regulated in the long term?" f7 a. F+ e: b+ Z; R/ i5 E
Some researchers want a total ban on wildlife trade, without exceptions, whereas / B( K R/ y7 |3 R' ]( Cothers say sustainable trade of some animals is possible and benefificial for peo1 q: T2 x: L$ p3 {( B6 S& M
ple who rely on it for their livelihoods. Banning wild meat consumption could " |! y- d9 I& W7 S4 Ocost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil( M/ X3 ?/ q1 s) `1 p/ N# u" ^
lion people out of a job, according to estimates from the non-profifit Society of : |6 ] n! B0 x% d5 r* xEntrepreneurs and Ecology in Beijing.9 {, B4 l& Q) w/ [8 `
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology3 j& x3 b& b% @
in China, chasing the origin of the deadly SARS virus, have fifinally found their! p, I# u8 b, J3 Z
smoking gun in 2017. In a remote cave in Yunnan province, virologists have & q/ K2 P S/ |5 e7 w1 xidentifified a single population of horseshoe bats that harbours virus strains with 3 V; U4 F/ Z8 _1 M0 \( jall the genetic building blocks of the one that jumped to humans in 2002, killing" l) j+ i( L" y+ d
almost 800 people around the world. The killer strain could easily have arisen P, I. i, K# c8 h& A' K% U
from such a bat population, the researchers report in PLoS Pathogens on 30 + g5 `1 M6 l8 @$ j( P( S, @November, 2017. Another outstanding question is how a virus from bats in7 Z* Y5 p2 w. }1 z( q( a
Yunnan could travel to animals and humans around 1,000 kilometres away in " z6 O9 Z8 j* P/ Z G* ^Guangdong, without causing any suspected cases in Yunnan itself. Wildlife3 Z" v* V1 ?; p- P- H: U# L/ s
trade is the answer. Although wild animals are cooked at high temperature$ D" ?* N& O) [( L" d: \
when eating, some viruses are diffiffifficult to survive, humans may come into contact R1 z ]- E- l! j$ G) S
with animal secretions in the wildlife market. They warn that the ingredients2 |. T0 [) K- E/ z" Q
are in place for a similar disease to emerge again. 0 c0 {5 j4 d+ J- Y" k9 |2 `Wildlife trade has many negative effffects, with the most important ones being: 3 t( W# ]- B" {1Figure 1: Masked palm civets sold in markets in China were linked to the SARS& a" E P% h& T* X
outbreak in 2002.Credit: Matthew Maran/NPL' a# Z' N2 f! d+ T6 D9 u$ k+ g
• Decline and extinction of populations' r! c, U+ F, `1 b2 p7 ]7 p
• Introduction of invasive species " S! A& |% J. \7 C5 r• Spread of new diseases to humans ' x2 o% {+ n. p: v7 ?- dWe use the CITES trade database as source for my data. This database4 B' `- }/ k# K2 g. ~' d$ D7 O
contains more than 20 million records of trade and is openly accessible. The & t* r, g- @2 _/ Pappendix is the data on mammal trade from 1990 to 2021, and the complete5 t0 ?3 a ~2 {9 [- J' }
database can also be obtained through the following link:/ ]! f3 r u% t
https://caiyun.139.com/m/i?0F5CKACoDDpEJ! Y F. |$ b5 X
Requirements Your team are asked to build reasonable mathematical mod ; Q* [8 B" J2 |! n" g) }5 ~els, analyze the data, and solve the following problems: " _% c3 R7 l4 A, A- K1. Which wildlife groups and species are traded the most (in terms of live 5 S" t; {0 \2 _8 t/ `5 D0 canimals taken from the wild)? + J' d3 R5 ^0 c9 b/ {2 Z- M2. What are the main purposes for trade of these animals? $ q0 f; c# F& {8 y2 @; w* I3. How has the trade changed over the past two decades (2003-2022)?( u# j+ `0 P+ _$ V: f4 Z
4. Whether the wildlife trade is related to the epidemic situation of major ; [9 h' q4 N4 Binfectious diseases?' L: j/ l" G) o
25. Do you agree with banning on wildlife trade for a long time? Whether it & M$ Z+ M; F: q, qwill have a great impact on the economy and society, and why? 9 g4 X @+ K/ [6. Write a letter to the relevant departments of the US government to explain 8 K: u/ G9 N0 |- s' ^your views and policy suggestions.9 p/ d4 p$ i; v8 F& q$ i
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