2022小美赛赛题的移动云盘下载地址 9 p8 M' o3 |. n3 P: k. i
https://caiyun.139.com/m/i?0F5CJAMhGgSJx - d# h* |' c+ ^$ m! a0 A2 I9 x3 B, t 0 O* f& ~; D; n3 \9 ]3 l7 @2022" q! a1 I# t+ U) O$ d+ \
Certifificate Authority Cup International Mathematical Contest Modeling 1 ]7 p; a2 Y- I, U$ k1 shttp://mcm.tzmcm.cn% b! A( L+ y0 U7 M
Problem A (MCM)/ }# q" G: u5 Z# J- Q2 |+ F9 V5 \
How Pterosaurs Fly$ h0 E* w# h+ S( m0 V
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They $ L3 `8 G/ i0 u! @: cexisted during most of the Mesozoic: from the Late Triassic to the end of ( Z3 [/ I! r+ t0 m5 f$ u+ G% ` Vthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved 9 v: Q4 U X i! i- i& Rpowered flflight. Their wings were formed by a membrane of skin, muscle, and; T3 B$ K6 c( Q8 Z4 L# b( v
other tissues stretching from the ankles to a dramatically lengthened fourth 1 y0 s5 {; g) }. N/ E- y% ]fifinger[1].) ?8 Z, K' ^) U$ {8 F" a
There were two major types of pterosaurs. Basal pterosaurs were smaller, ^' C) d6 |9 ?; V( H
animals with fully toothed jaws and long tails usually. Their wide wing mem% o% s0 s+ E5 o/ u% L& y1 E
branes probably included and connected the hind legs. On the ground, they 2 Y8 z e5 s* A; U p2 g+ pwould have had an awkward sprawling posture, but their joint anatomy and: G3 |9 F' ~0 W; R* U( H) j( n
strong claws would have made them effffective climbers, and they may have lived ; d3 s( G6 D. gin trees. Basal pterosaurs were insectivores or predators of small vertebrates. ( y9 M0 N; L7 E7 |Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. - Y; X5 K ] F4 {9 o5 TPterodactyloids had narrower wings with free hind limbs, highly reduced tails,6 E0 K+ B1 E8 k; O0 h) |8 N& M
and long necks with large heads. On the ground, pterodactyloids walked well on" {/ R! h7 h! L0 ?# }* C- D! g
all four limbs with an upright posture, standing plantigrade on the hind feet and : ~* ?" O7 E( ?% q/ z: R" Y4 ffolding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil 1 ?. {2 s1 ]" I3 V" i% ktrackways show at least some species were able to run and wade or swim[2]. 6 o, r0 I Z1 F3 j* VPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which ' f9 e2 R0 O- t, icovered their bodies and parts of their wings[3]. In life, pterosaurs would have ( T+ a' @$ A, f2 S0 Jhad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug# v4 M Z1 a0 f8 K" h" h5 t
gestions were that pterosaurs were largely cold-blooded gliding animals, de0 T4 P4 B1 G3 S$ e( o; N
riving warmth from the environment like modern lizards, rather than burning7 v0 U. Q! q- J; ^
calories. However, later studies have shown that they may be warm-blooded" B0 v7 }1 V1 L3 ^7 S
(endothermic), active animals. The respiratory system had effiffifficient unidirec+ Q! \1 n G% |
tional “flflow-through” breathing using air sacs, which hollowed out their bones, U+ x+ \( }) Y7 b% X
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from 5 w8 X/ {! d/ g9 tthe very small anurognathids to the largest known flflying creatures, including 1 w z, x$ c) j j, hQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 0 M3 s( v! `, @- }$ Rnine metres. The combination of endothermy, a good oxygen supply and strong( N# Y& p: ^" J0 z$ F
1muscles made pterosaurs powerful and capable flflyers. p3 b7 D1 x2 T, E
The mechanics of pterosaur flflight are not completely understood or modeled & a- J0 k C+ V$ e1 G" [at this time. Katsufumi Sato did calculations using modern birds and concluded . G- b6 i4 G/ [, ?that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,: R6 a) H7 ^2 m. D" E; {
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able - U5 D/ D! y" m) V3 Kto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].- _2 J, l/ d9 g- o j" a T. p
However, both Sato and the authors of Posture, Locomotion, and Paleoecology2 ?9 l2 B L8 a, \2 S+ Y& ^! R
of Pterosaurs based their research on the now-outdated theories of pterosaurs ( C/ w* s. o/ l. g4 Ibeing seabird-like, and the size limit does not apply to terrestrial pterosaurs,2 [0 _* D% K. l1 f* P
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that $ Z( \! a6 M: |/ Z0 ~atmospheric difffferences between the present and the Mesozoic were not needed I8 ^+ ?+ w7 u; B! D4 C/ k+ }for the giant size of pterosaurs[8].! H6 k8 k1 Y+ o% ?% L2 [
Another issue that has been diffiffifficult to understand is how they took offff.; J# r* ^- R4 V! @( F
If pterosaurs were cold-blooded animals, it was unclear how the larger ones: a* V0 v. P+ b# m' k
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage , P6 h/ {! L* Ya bird-like takeoffff strategy, using only the hind limbs to generate thrust for: q7 u m4 i8 {) N9 g. g& X
getting airborne. Later research shows them instead as being warm-blooded 2 R4 f8 `6 _- c: b% cand having powerful flflight muscles, and using the flflight muscles for walking as 0 r2 k8 s$ n+ O8 c' Qquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of 4 r, o4 j/ K$ EJohns Hopkins University suggested that pterosaurs used a vaulting mechanism * @! l; R6 V& Gto obtain flflight[10]. The tremendous power of their winged forelimbs would ! s. C1 Y5 Y+ v6 Q7 E& eenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds - h1 v9 V. Y1 ?0 ^. ?% ]of up to 120 km/h and travel thousands of kilometres[10]. $ @; V2 @# O. j8 P; x0 m3 e! NYour team are asked to develop a reasonable mathematical model of the ( F9 m, O8 ^% I% a# Yflflight process of at least one large pterosaur based on fossil measurements and ' \6 N$ Y8 Q J3 i' M6 s" g6 J9 cto answer the following questions. * r- m* s" D8 `# i. `& Z# I1. For your selected pterosaur species, estimate its average speed during nor 4 \' N+ |6 e) j" T/ \# Zmal flflight.; `" F+ ^, J* l6 w* Z7 u
2. For your selected pterosaur species, estimate its wing-flflap frequency during8 X" k8 v) H/ S, M3 f8 R
normal flflight. - H1 I! v( W4 r2 F3. Study how large pterosaurs take offff; is it possible for them to take offff like6 q; x; k" e ]6 a
birds on flflat ground or on water? Explain the reasons quantitatively.9 @7 Y" f: {5 M. T/ {. X: V
References 4 o2 }8 `! U2 v[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight! s+ p1 Q. }& o8 h4 a, ]+ N
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111. " ]- d' K$ ?1 E2[2] Mark Witton. Terrestrial Locomotion. ) x- X4 l0 V& ~! hhttps://pterosaur.net/terrestrial locomotion.php 3 x7 a& t4 \( T- o[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs . u: [$ o, i* }$ O- DWere Covered in Fluffffy Feathers. https://www.livescience.com/64324-$ k, R8 G( N1 u6 _) p. b4 i+ {3 G
pterosaurs-had-feathers.html" V' _/ o2 ], K+ I. Z* K0 ^1 G
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a : O: v9 K% v0 a' w; d. m9 S3 \9 erare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)% W1 w' A4 Y7 I( ? U5 S8 a/ A, L, V
from China. Proceedings of the National Academy of Sciences. 105 (6): 1 l1 V, E8 q, T1 ^' s0 U2 }* y1983-87.1 Y' N: r! @, U
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust" h m h" o2 D; P( P; D# D
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):/ K8 u, E* u" `% s
180-84. 9 l4 E, c j) k4 ~8 g[6] Devin Powell. Were pterosaurs too big to flfly?% T! O5 ~# O( c, ~; w" P
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs7 }1 c$ e- b- X/ C5 _6 T( X
too-big-to-flfly/ 7 I: h, y3 y$ x+ k[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology' N$ K- L8 F" }- F( C
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60., p3 {% w/ a" H4 Q& I% I& `( O
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable8 _, V7 ~7 {! T6 D2 w
air sacs in their wings. ) u- D" Z5 s( n& c7 K% Y$ Rhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur3 t x" [* S+ @
breathing-air-sacs0 G/ x2 C* o: d7 t. i
[9] Mark Witton. Why pterosaurs weren’t so scary after all. 0 o8 r7 F. i; fhttps://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils : @3 `7 ~( B, }* Eresearch-mark-witton 2 U- e8 c) x' o[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? x; X: @* e: _# ^4 k+ l
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs$ Z! v- e/ m" ~
vault-aloft-like-vampire-bats/+ I4 K3 u0 i& z
4 ~- x: m, L1 Z. T6 h& }' D1 J) Z) H2022 3 e5 @2 f9 u r& m* YCertifificate Authority Cup International Mathematical Contest Modeling , b k) [: p& v! V; Ahttp://mcm.tzmcm.cn 4 ?; T2 L, X, Z, L# PProblem B (MCM)8 R T0 q4 S5 Y4 j
The Genetic Process of Sequences ! g. f1 ^* `5 j% g7 {1 q' j W+ NSequence homology is the biological homology between DNA, RNA, or protein % Q* z$ s* W$ ysequences, defifined in terms of shared ancestry in the evolutionary history of , h4 {" J0 O( k G" q; T. W1 k1 Glife[1]. Homology among DNA, RNA, or proteins is typically inferred from their 6 d u. b2 K8 f. j' ^nucleotide or amino acid sequence similarity. Signifificant similarity is strong ( K$ A; c' C% n5 w9 Cevidence that two sequences are related by evolutionary changes from a common 4 B. q6 T& b! H2 b: r3 Hancestral sequence[2]. 8 K' t* [/ _$ K, S1 J; oConsider the genetic process of a RNA sequence, in which mutations in nu* N, H9 g8 o$ a
cleotide bases occur by chance. For simplicity, we assume the sequence mutation . y) Q- w8 w6 ^7 @$ v! A/ Z5 garise due to the presence of change (transition or transversion), insertion and # c: v# L; V& l: zdeletion of a single base. So we can measure the distance of two sequences by7 y! K# J; w1 X3 H
the amount of mutation points. Multiple base sequences that are close together6 f' P* h2 C( @8 l- |5 m' c' a
can form a family, and they are considered homologous.( y! x" y& p% m; {" N0 }
Your team are asked to develop a reasonable mathematical model to com$ a5 Y5 p; M8 {) G. r
plete the following problems. 5 [ H1 w) V4 ]0 E1. Please design an algorithm that quickly measures the distance between 4 w' A0 y0 q! o- P6 utwo suffiffifficiently long(> 103 bases) base sequences.6 K {0 o$ [2 }
2. Please evaluate the complexity and accuracy of the algorithm reliably, and4 H; F+ J% N' n% ?! Q% y( y
design suitable examples to illustrate it.; G8 l2 n3 D) z' }2 D- @# p
3. If multiple base sequences in a family have evolved from a common an 8 V4 c# N/ g" K5 Ccestral sequence, design an effiffifficient algorithm to determine the ancestral ! r5 `' \: {/ H3 osequence, and map the genealogical tree.# t0 R* P" {5 {0 I" \, ^% K* ~
References0 i" K7 C5 Q u9 L8 E2 z* x0 D' h
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re ! @/ @% X; P, q( W8 Tview of Genetics. 39: 30938, 2005./ T% H; k5 H- I% f: ]. ` I% z
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,; p+ Y2 h, \. Q3 s2 \, q
et al. “Homology” in proteins and nucleic acids: a terminology muddle and1 `1 w: _ P* P2 f q
a way out of it. Cell. 50 (5): 667, 1987. 6 e. {2 X( I! j2 Z$ p0 H) n6 p3 j# X$ \) C
2022 . @( z5 [' F. w) BCertifificate Authority Cup International Mathematical Contest Modeling 3 n; Q/ q1 v4 j5 _8 hhttp://mcm.tzmcm.cn * C* d8 Y/ x% ^0 g' TProblem C (ICM)" l. I1 k- D$ g2 G
Classify Human Activities 8 O6 {2 z h" R4 p" b; I' Z* nOne important aspect of human behavior understanding is the recognition and Q) R3 ~, B+ Z% I. C; Q
monitoring of daily activities. A wearable activity recognition system can im5 f4 f/ ` p' Q- e
prove the quality of life in many critical areas, such as ambulatory monitor6 m$ ?( x+ A- ?" b( O
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ( b. A$ i" _( o! M* L6 L
ity recognition systems are used in monitoring and observation of the elderly4 d3 ]. @: _( Z1 ^
remotely by personal alarm systems[1], detection and classifification of falls[2],0 o9 f2 S' `/ E9 ^* u
medical diagnosis and treatment[3], monitoring children remotely at home or in3 D* U" b( j% G7 C9 j0 M! c
school, rehabilitation and physical therapy , biomechanics research, ergonomics,0 l3 L/ e' G$ @6 A1 F# C) q
sports science, ballet and dance, animation, fifilm making, TV, live entertain ; S- \- |. k7 _6 u, }ment, virtual reality, and computer games[4]. We try to use miniature inertial! K$ }9 [" l$ p* v
sensors and magnetometers positioned on difffferent parts of the body to classify* N, d2 [* O/ g8 E; f% t) ^, J) U7 u
human activities, the following data were obtained. 6 b* S. G+ c! L' @Each of the 19 activities is performed by eight subjects (4 female, 4 male, % o; e/ c; d: E( X3 {% rbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes # @4 h* d3 b" j0 Q' C1 b- Wfor each activity of each subject. The subjects are asked to perform the activ/ f1 m! K* n, t, S
ities in their own style and were not restricted on how the activities should be: s6 H/ D9 C& g( Z: v
performed. For this reason, there are inter-subject variations in the speeds and2 f* n4 W% x3 K E6 V0 u
amplitudes of some activities.3 n% Z5 u* p d7 U, N. ]
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. 2 `, g' z/ N- Y' pThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal# A; [' ]9 P4 o+ Z9 _" Q$ P! Y
segments are obtained for each activity.! E! k2 M3 W. S. y, G& `
The 19 activities are:3 A. ^3 z! e$ j3 s& G5 h
1. Sitting (A1); % a0 E5 t/ R1 F( Z; g* J+ C6 H2. Standing (A2); ; v% q5 U0 t7 }' K- g+ O3. Lying on back (A3); + {# P! G! p6 q4 `% F4. Lying on right side (A4);9 h+ M0 {. S' Y
5. Ascending stairs (A5);& x4 L$ C# W" v9 a( N+ f" {- n
16. Descending stairs (A6); 4 T- U, j7 A( r2 x6 O7. Standing in an elevator still (A7); & ?! \; [, w8 l& C0 r8. Moving around in an elevator (A8);* D2 d _2 J+ m
9. Walking in a parking lot (A9); . w! C& U! n) o- o5 k10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg 7 |9 |4 D1 \. x, ^* X9 yinclined positions (A10); ' K( n9 w" ?0 e) k! l' @0 F11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions & ^8 G( w/ P9 f* v(A11);5 R& l2 q1 s6 i6 S% d' L' o
12. Running on a treadmill with a speed of 8 km/h (A12);7 A; I5 j' W9 n8 z* ~
13. Exercising on a stepper (A13); 8 }/ o3 |6 p- M14. Exercising on a cross trainer (A14);' |7 h7 V% w6 O* K' C$ X
15. Cycling on an exercise bike in horizontal position (A15); 0 Z4 ?0 Z, Z* w- T16. Cycling on an exercise bike in vertical position (A16); $ v/ d* ~' C A/ f. o- o0 t+ C8 x17. Rowing (A17);* e' f U0 v |% M8 I1 w! S8 r2 `
18. Jumping (A18); . j0 k5 D. S `5 A7 D/ ?0 _19. Playing basketball (A19).* N- g5 K6 e4 u' B
Your team are asked to develop a reasonable mathematical model to solve$ f: m, Q% Y6 S0 K4 ?2 `0 h
the following problems. ! P& ?1 N0 a1 r. E" Z" G+ w1. Please design a set of features and an effiffifficient algorithm in order to classify - T [) ?8 r, [3 v4 Wthe 19 types of human actions from the data of these body-worn sensors.* w& ^( O' t+ L; H0 @, K; D
2. Because of the high cost of the data, we need to make the model have8 l- k& a% @, v: r4 V s: w
a good generalization ability with a limited data set. We need to study* D. n2 I- G2 y# x* G+ \
and evaluate this problem specififically. Please design a feasible method to8 R2 w1 }; ~5 B3 u
evaluate the generalization ability of your model.% Q0 e* V$ Y) h# ^8 i+ I
3. Please study and overcome the overfifitting problem so that your classififi- / Y7 T0 C x2 P& I& S6 Mcation algorithm can be widely used on the problem of people’s action3 \: v" ^# _( e1 i4 F$ _. e; u
classifification.: k9 O! E+ s. B8 A: t" U' k
The complete data can be downloaded through the following link:: x% n( g9 w% J4 q6 V0 |7 r
https://caiyun.139.com/m/i?0F5CJUOrpy8oq3 p9 H3 Z# l0 b/ L5 C. q S- |( z
2Appendix: File structure. p/ A+ x% L5 s0 g
• 19 activities (a) ( d+ K6 G$ t- ]9 @* {% G9 g, v• 8 subjects (p) - Z6 k$ }6 v O) }5 D8 n• 60 segments (s) 6 D( H7 U( j' \0 K• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left% a3 }: _, D" }! e9 p
leg (LL)5 @" P& H' ?" c3 U! }
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z( ~8 U7 B/ L: K9 J( V6 @8 ^' T
magnetometers)/ x, H, v8 ^" ?" ?( a
Folders a01, a02, ..., a19 contain data recorded from the 19 activities. $ w9 G) V/ `" Q7 d" j) Y Y3 qFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the $ `- S1 P+ n7 X& o8 subjects.* D. D! Z. `( G
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each: F" Q3 W9 J% [6 c
segment. , V! f( S( L4 r' e6 g- V, k# g# X( MIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 253 a6 R6 W3 X5 J- ~8 a
Hz = 125 rows. X1 F; `% G @% l# y% F; aEach column contains the 125 samples of data acquired from one of the8 b1 {& q) p. h( m
sensors of one of the units over a period of 5 sec. ! i' M* N* s- C0 u$ \3 hEach row contains data acquired from all of the 45 sensor axes at a particular2 g- h) P. z; ^' O
sampling instant separated by commas.4 R% f+ l* [( b) y9 K4 o" `4 @/ c
Columns 1-45 correspond to:: ^) V- ?+ b7 H q
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,: z6 s& F( W/ V/ k6 J; W0 L
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,4 P# P8 f8 K1 b6 [( t
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, : k {- f8 h* z+ _• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,9 J0 t9 l* }! v: `" E( k+ o
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. 1 @9 f q& [# f4 h5 Z8 e3 KTherefore,7 M Y& N( @* e2 }8 }5 ]
• columns 1-9 correspond to the sensors in unit 1 (T), % ]/ g# V+ @- m, k# I• columns 10-18 correspond to the sensors in unit 2 (RA),1 R5 z( n5 s8 K m( ~0 x9 N
• columns 19-27 correspond to the sensors in unit 3 (LA), D( A% ^; H8 K• columns 28-36 correspond to the sensors in unit 4 (RL), / e, R! V' n7 s4 X• columns 37-45 correspond to the sensors in unit 5 (LL).+ N* X7 _" @* V4 u+ f! E. Z
3References" c9 J, d7 M T6 K
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic / ^( a* U, A# T2 j. M4 p d2 Bdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.+ h9 l) z8 J( F/ x
42(5), 679-687, 2004 ' I) ]2 k+ ]) h; L, O. l0 Q1 {* ^; b[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of7 Q% N2 o- O7 Q; t# q! c) i) h
low-complexity fall detection algorithms for body attached accelerometers. G) f( z. c# uGait Posture 28(2), 285-291, 2008 ; R- ]5 q4 M, i; w, a2 t' L[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag 5 }- C# q: C5 ?% i) z4 v( |% @nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.# o& {& t# W5 {3 k3 K& x2 _
B. 11(5), 553-562, 2007 % `$ S) D3 y4 \9 @[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con * l9 j3 t/ L3 s* C* K! t4 g E6 a( o: Ktrol of a physically simulated character. ACM T. Graphic. 27(5), 2008. S; a/ S( l7 r4 W% K5 o8 d
* M3 S/ P3 P8 P20227 u2 A6 a0 h- M
Certifificate Authority Cup International Mathematical Contest Modeling: x" n* k2 ~4 f5 l3 e% H
http://mcm.tzmcm.cn * }9 t/ z, t4 p% h3 |1 h4 q5 oProblem D (ICM): Z" t" G S% d9 D
Whether Wildlife Trade Should Be Banned for a Long : \5 x3 {" O7 q) xTime- m) [1 P3 z' U; A9 X- f
Wild-animal markets are the suspected origin of the current outbreak and the / z& T" y+ Z" G* x2002 SARS outbreak, And eating wild meat is thought to have been a source # H; k/ T* q: {of the Ebola virus in Africa. Chinas top law-making body has permanently 2 {0 o4 a6 v$ u0 B! _tightened rules on trading wildlife in the wake of the coronavirus outbreak,6 c' W, y3 O5 O: T1 E
which is thought to have originated in a wild-animal market in Wuhan. Some ( l4 m7 `+ m3 x C* Xscientists speculate that the emergency measure will be lifted once the outbreak 7 X/ z3 V' N: Q* v* k# o, ~ends.9 `# F) W0 x3 C) T9 V
How the trade in wildlife products should be regulated in the long term? ( J4 |! X& n7 |8 f, HSome researchers want a total ban on wildlife trade, without exceptions, whereas. |" ]3 j( I& x! ]- K
others say sustainable trade of some animals is possible and benefificial for peo" y% A& l8 W: d- G' x
ple who rely on it for their livelihoods. Banning wild meat consumption could- a. c! K6 ^! _. I$ e
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil 4 w" d) R3 ^& \8 Y' T. W6 \lion people out of a job, according to estimates from the non-profifit Society of1 H3 Q6 @8 ^4 x3 W
Entrepreneurs and Ecology in Beijing./ D- Q+ T" Y: `3 v" w
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology' v4 b, p- p: v0 [6 ~" e
in China, chasing the origin of the deadly SARS virus, have fifinally found their 2 {; w( N9 R$ e K+ r* W& g- Z/ m2 Ksmoking gun in 2017. In a remote cave in Yunnan province, virologists have ( q k& O3 w. i3 d3 ?' {* lidentifified a single population of horseshoe bats that harbours virus strains with7 H, z+ y% {9 d3 B* h6 l
all the genetic building blocks of the one that jumped to humans in 2002, killing : s5 c7 @ Y. \& j- e# M8 C$ Talmost 800 people around the world. The killer strain could easily have arisen0 g$ ?+ u# a2 {
from such a bat population, the researchers report in PLoS Pathogens on 30, M; u" L' X. @1 o
November, 2017. Another outstanding question is how a virus from bats in 1 T0 L$ T+ ^4 ?( A. VYunnan could travel to animals and humans around 1,000 kilometres away in- _* n- M1 O" I
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife # C# Q& R2 W6 u P3 ^" otrade is the answer. Although wild animals are cooked at high temperature$ y. Z H) C/ T! W. H/ |; g" u
when eating, some viruses are diffiffifficult to survive, humans may come into contact 7 d( J# T- p5 T8 F# Z) iwith animal secretions in the wildlife market. They warn that the ingredients4 `1 h+ j& q5 d- {" x. x7 G( M. M
are in place for a similar disease to emerge again. - s9 I$ x" ^: p8 n: LWildlife trade has many negative effffects, with the most important ones being:7 w* E; Y; ]0 b" O! l& L
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS : q& C& W* I2 Z$ h3 v% l) Houtbreak in 2002.Credit: Matthew Maran/NPL ( Z' M& B( J9 q4 C% D! J2 p3 r• Decline and extinction of populations5 ]! d# [; ]6 H; M+ f* x4 V
• Introduction of invasive species 6 V }: d- X6 i# d8 d" T. m• Spread of new diseases to humans ; C! i+ H0 K; Q \+ c6 hWe use the CITES trade database as source for my data. This database : K. q1 @: N3 B5 c$ C5 H+ \5 j$ R' mcontains more than 20 million records of trade and is openly accessible. The 8 o7 b4 M7 b/ ? z. M2 B4 ?appendix is the data on mammal trade from 1990 to 2021, and the complete' V% }0 ]! l. y) f
database can also be obtained through the following link: 4 y2 e% W: D% |: c0 s$ ?https://caiyun.139.com/m/i?0F5CKACoDDpEJ7 C2 l+ |: i! H5 m9 y6 x
Requirements Your team are asked to build reasonable mathematical mod 7 |% g: L8 {' cels, analyze the data, and solve the following problems: ; R: l' P/ @) J1. Which wildlife groups and species are traded the most (in terms of live1 c! C# |/ N/ ?' A; p* d- M
animals taken from the wild)?0 ?/ I9 V2 E" @
2. What are the main purposes for trade of these animals?. J9 o" c! Q% g0 h( @: ]
3. How has the trade changed over the past two decades (2003-2022)? 2 z9 T3 T' g% j6 J% ]) A4. Whether the wildlife trade is related to the epidemic situation of major% Q H3 e* \0 ~5 ~: b( h, i
infectious diseases?8 h: v/ H* U) W1 S5 \# O5 M
25. Do you agree with banning on wildlife trade for a long time? Whether it; n; B* S$ w9 q4 x A
will have a great impact on the economy and society, and why?" P4 z) U' b( o1 M6 u0 `/ c8 {+ k
6. Write a letter to the relevant departments of the US government to explain T4 g; L% {! I1 Q( `; h. ~your views and policy suggestions. ! S6 b5 I+ y' z, P: n& F 3 e; T" ?9 L7 U2 D! ]$ j! u* p8 [$ }' ?
& ^; L$ E3 {( J' ?& g% j2 C / u+ @- ^5 T/ _' @: o1 A' y $ U; e) ?3 G2 J& [# c9 E, ?8 ?& y6 c! [0 S3 R
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