2022小美赛赛题的移动云盘下载地址 ( Z: B& a9 W+ |. b" k- S$ z
https://caiyun.139.com/m/i?0F5CJAMhGgSJx ; z2 U9 Y0 G0 [7 R ! f% Z# x( D0 o ~) _2022; g$ i3 m% C" o) w
Certifificate Authority Cup International Mathematical Contest Modeling2 g% T2 t7 t5 ]7 }
http://mcm.tzmcm.cn# c+ z+ N0 Q, N& t$ b) U/ A& c
Problem A (MCM)0 `2 `% O3 Y; j3 I/ T
How Pterosaurs Fly : }$ \/ j- \% L, l$ rPterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They w; Y$ c; O5 t# d' k9 ~8 Nexisted during most of the Mesozoic: from the Late Triassic to the end of ' y5 B+ S3 r3 x( \& zthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved # \5 I' M) N) Z6 ^& W& F/ H$ vpowered flflight. Their wings were formed by a membrane of skin, muscle, and $ x7 w ]% k: b, x0 O0 L, s! ~; pother tissues stretching from the ankles to a dramatically lengthened fourth ) ^+ M% l" e' w% p' y7 Efifinger[1]. & Q: y6 c* @" w6 d! s" nThere were two major types of pterosaurs. Basal pterosaurs were smaller " D# v8 t6 @) h- N2 k' E- Nanimals with fully toothed jaws and long tails usually. Their wide wing mem2 K- G4 }! _1 p# b$ m
branes probably included and connected the hind legs. On the ground, they! ]! s$ h' e8 y$ k5 P3 q1 ~
would have had an awkward sprawling posture, but their joint anatomy and 9 z( X( S2 q" g% ~$ z" Vstrong claws would have made them effffective climbers, and they may have lived ! s$ n; }7 F% \$ L5 u$ \' }9 }in trees. Basal pterosaurs were insectivores or predators of small vertebrates. & W& _7 [. ? ~% N- c; r: xLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. 0 q1 E' Y& N OPterodactyloids had narrower wings with free hind limbs, highly reduced tails, 9 h& |# v2 g6 P! B) k+ R* Aand long necks with large heads. On the ground, pterodactyloids walked well on : u$ {. e9 i: {( ~all four limbs with an upright posture, standing plantigrade on the hind feet and! C% J( C4 F5 q
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil& t& C" M9 F5 o4 v6 X, k! @
trackways show at least some species were able to run and wade or swim[2]. ' X: |5 W* [# a* I# F3 O* Z" mPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which 1 q+ }6 C5 ~/ s* Xcovered their bodies and parts of their wings[3]. In life, pterosaurs would have& U8 V0 R8 {# |! `, a9 c* {8 d
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug$ O$ C) {; \+ }' y% D* E+ q
gestions were that pterosaurs were largely cold-blooded gliding animals, de 9 ^2 Y8 o; n& R, b6 V: Vriving warmth from the environment like modern lizards, rather than burning 1 f' E i( P( `; L& \; Hcalories. However, later studies have shown that they may be warm-blooded* f0 B, ^% v3 Y: [" V6 w
(endothermic), active animals. The respiratory system had effiffifficient unidirec- R( Z, u4 ?# |
tional “flflow-through” breathing using air sacs, which hollowed out their bones* f* I8 S1 Y: s) v! `1 Q
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from : R8 n" L& S; y6 y) r6 l/ Nthe very small anurognathids to the largest known flflying creatures, including + S0 k- c/ @. j- s! ^% v8 zQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 4 a: U6 E/ g4 J1 C! s1 tnine metres. The combination of endothermy, a good oxygen supply and strong % n- |/ S* N8 ?: s5 M1muscles made pterosaurs powerful and capable flflyers. . l2 w' D D9 {5 l6 wThe mechanics of pterosaur flflight are not completely understood or modeled9 J1 [: @7 R' h% `2 O1 ~
at this time. Katsufumi Sato did calculations using modern birds and concluded 3 Q! \1 c6 N u% Z: Y' Lthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture, 2 V" P5 `" ^% a: X L. c$ d$ WLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able9 |4 E7 ~0 O5 d1 N
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]./ p6 T, n* e+ {3 Y# o! F+ p u
However, both Sato and the authors of Posture, Locomotion, and Paleoecology2 [, V: {" b# F
of Pterosaurs based their research on the now-outdated theories of pterosaurs 3 ~" _6 o4 y' W3 v# Q+ I8 G% W. }# Jbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, * P9 t3 X+ S* G2 x: |+ |) vsuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that, w# z- e& ~# M5 \
atmospheric difffferences between the present and the Mesozoic were not needed% c2 M0 L) F& o2 |' C
for the giant size of pterosaurs[8].- a! j8 o; ~/ X! W
Another issue that has been diffiffifficult to understand is how they took offff./ e4 k$ w/ G* X4 A% Z
If pterosaurs were cold-blooded animals, it was unclear how the larger ones( b) F6 G! m- H5 {/ {
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage( L* Z6 t- Y m
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for2 W* }( z1 C* g0 _" V
getting airborne. Later research shows them instead as being warm-blooded$ A6 i2 t6 b! w6 k! S1 I) i' ~
and having powerful flflight muscles, and using the flflight muscles for walking as4 C3 F6 R* }$ w: _* |( O- N% ^
quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of, t- D9 s \* X! _$ F" _
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism 9 \& P; J, {# V: B" Y% N) oto obtain flflight[10]. The tremendous power of their winged forelimbs would; A1 }7 G" s7 m0 L4 }5 e y
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds : H1 s8 I# G+ W$ fof up to 120 km/h and travel thousands of kilometres[10]. 0 @3 N; I i% G- A* L2 wYour team are asked to develop a reasonable mathematical model of the / [, e6 ^$ E2 l& I2 Q* rflflight process of at least one large pterosaur based on fossil measurements and9 v( H3 ?4 V6 d+ E @
to answer the following questions.+ b ~6 H8 j; }! b9 H
1. For your selected pterosaur species, estimate its average speed during nor , u" T8 z, a' A2 z1 `' I- ]mal flflight. ) O' o, H* Y' ?4 H6 a2. For your selected pterosaur species, estimate its wing-flflap frequency during ; E- x0 F/ [, Y8 Bnormal flflight. " g, C* A& q, x2 [8 t$ Z3. Study how large pterosaurs take offff; is it possible for them to take offff like u9 _: Y# ~( g. G/ z+ [2 x4 d1 g, Mbirds on flflat ground or on water? Explain the reasons quantitatively. ! m/ b- f' [$ qReferences ) \& ~) V8 O+ L[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight1 }2 K: y" u6 h l+ L2 r0 N
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111. A- D8 \4 W% X i* i0 H2[2] Mark Witton. Terrestrial Locomotion.4 Y, E$ q: a1 ?* O! N
https://pterosaur.net/terrestrial locomotion.php& B' e6 z" \% D
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs $ `; k, I2 d/ F4 e+ DWere Covered in Fluffffy Feathers. https://www.livescience.com/64324-# z5 w- e( I& t- ]" L) O$ U
pterosaurs-had-feathers.html * j, r/ X7 }$ u: t0 G[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a# ]/ ^2 k* c( b7 t# z) S; O. I
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)5 f) c9 h8 G+ j) C1 \+ k
from China. Proceedings of the National Academy of Sciences. 105 (6): / M O) ^0 V: r! N1 ]9 E3 O1983-87.# q; P0 i1 S! i! M
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust2 @$ S6 F% j" }1 i+ y0 U, b
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):# D3 l0 x, u1 A* x l9 q# {
180-84.5 ~9 m; N0 r& b! m
[6] Devin Powell. Were pterosaurs too big to flfly?/ p5 V# z% m) e, U* g4 u& w
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs1 L( d7 ^" Q3 i. Y: M8 `
too-big-to-flfly/ / f+ O' Q. C# i/ T! q[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology + I" K/ Q6 g. S; o, _, uof pterosaurs. Boulder, Colo: Geological Society of America. p. 60.4 K2 B! q* M1 d2 B( Y( h% c
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable ) q% q- Y+ b2 R9 xair sacs in their wings. ! B8 B3 E/ Z4 T& e. ^https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur . U9 J! N& ]& c- r5 ]$ u* ibreathing-air-sacs ! e5 t- ~" j; _! _! T6 O[9] Mark Witton. Why pterosaurs weren’t so scary after all.5 {$ t, }8 U# v: ?8 W. J! B8 I8 {
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils8 x$ ~1 I6 B, w6 a; G& H, f
research-mark-witton 7 v) ?9 w% w+ @# B8 ^1 P% ~' X* I* ^[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?7 v. A5 I9 D: |# D0 ^5 v
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs" |5 [- m0 m5 R+ v8 d
vault-aloft-like-vampire-bats/) D7 l( d) }' |
. V2 d. {/ {; m$ m: t
2022 5 D& ^! w5 R8 ]9 b RCertifificate Authority Cup International Mathematical Contest Modeling * V& e* l7 W% g( Bhttp://mcm.tzmcm.cn i& c. ]3 v3 N2 mProblem B (MCM)- \. A P0 j' f
The Genetic Process of Sequences4 P r" l9 b7 D/ M, q( Q" f
Sequence homology is the biological homology between DNA, RNA, or protein. u" K+ ~$ m. {- _
sequences, defifined in terms of shared ancestry in the evolutionary history of1 l( C8 O# r7 a! {9 b% X& D
life[1]. Homology among DNA, RNA, or proteins is typically inferred from their . I2 f! \4 D7 r- F% W' knucleotide or amino acid sequence similarity. Signifificant similarity is strong 7 a0 S+ v) Z9 [# K. levidence that two sequences are related by evolutionary changes from a common' G0 t$ K/ i5 g: p. D" j
ancestral sequence[2].& A$ Z6 Q% a8 Z+ w. T; v
Consider the genetic process of a RNA sequence, in which mutations in nu0 L, ^/ ~: Y* x" {1 g
cleotide bases occur by chance. For simplicity, we assume the sequence mutation 1 \, Q% ]6 D' k/ f) ~$ ^arise due to the presence of change (transition or transversion), insertion and+ |$ c# `3 Y' h, Z- b
deletion of a single base. So we can measure the distance of two sequences by, `- D. p# R/ K* L
the amount of mutation points. Multiple base sequences that are close together . [! Q1 \# S; d1 o, ^' Pcan form a family, and they are considered homologous. 3 v9 z! b/ u; L1 f c' n' j! ?Your team are asked to develop a reasonable mathematical model to com# B8 E. E x9 w9 {& {' Y8 Y
plete the following problems./ k H1 Z8 m. ^" V+ G6 B
1. Please design an algorithm that quickly measures the distance between7 P/ H$ S# K+ W% l' E! A
two suffiffifficiently long(> 103 bases) base sequences.* L* l; e. f; u
2. Please evaluate the complexity and accuracy of the algorithm reliably, and" H7 {+ `& r) g! e$ K B. T
design suitable examples to illustrate it. 0 m0 h1 E/ i& g! _3. If multiple base sequences in a family have evolved from a common an / ?) a+ b6 w+ T% o) ccestral sequence, design an effiffifficient algorithm to determine the ancestral ' l( k4 l( V. u$ ^sequence, and map the genealogical tree. * \& [1 h* r8 F+ t& B9 D/ m3 sReferences6 ~; \! Q, P! P g5 {( |( N/ D
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re 9 M# S8 N% v) f; w% [+ L) Lview of Genetics. 39: 30938, 2005. ' s! @; C9 G4 b$ i! o3 J) H6 n( q[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,1 t9 d$ _. D, h5 Q& x1 r, i/ ?$ k
et al. “Homology” in proteins and nucleic acids: a terminology muddle and9 e- u: ~: Z7 N% G; l
a way out of it. Cell. 50 (5): 667, 1987. ; G: v J( Q& d8 Y% S' R8 ~3 E W' u7 w1 l
2022 4 `; ?5 k" \( m7 t v, nCertifificate Authority Cup International Mathematical Contest Modeling3 T. }0 d f2 g
http://mcm.tzmcm.cn 4 l3 K" g/ _7 S7 z. w# d/ aProblem C (ICM)+ `8 ~, m; z" x. t( W3 V
Classify Human Activities5 R2 U" O) r; F9 q
One important aspect of human behavior understanding is the recognition and 5 |9 H" m9 r2 l2 H( Q8 dmonitoring of daily activities. A wearable activity recognition system can im , l9 q) h: h5 L) L7 dprove the quality of life in many critical areas, such as ambulatory monitor 3 i+ f5 e }" P5 l, N( ]! t* Ring, home-based rehabilitation, and fall detection. Inertial sensor based activ 0 L9 F& i0 q' X4 k- ^4 v4 E! {ity recognition systems are used in monitoring and observation of the elderly : k+ G9 r4 w) k. s \% @7 a0 premotely by personal alarm systems[1], detection and classifification of falls[2],) r8 K: b, i5 }' F) M
medical diagnosis and treatment[3], monitoring children remotely at home or in $ T, L/ K' U4 Eschool, rehabilitation and physical therapy , biomechanics research, ergonomics, 7 z4 b) `2 [$ h2 v- P: Jsports science, ballet and dance, animation, fifilm making, TV, live entertain0 g+ R" R5 f1 m2 p. u
ment, virtual reality, and computer games[4]. We try to use miniature inertial6 \- @) c& v( |! L' c2 O! l1 N
sensors and magnetometers positioned on difffferent parts of the body to classify8 M F& W& P2 U+ ?. C: v
human activities, the following data were obtained.2 b" f& Y+ }2 K) o* s; q5 a8 q
Each of the 19 activities is performed by eight subjects (4 female, 4 male,- O; ` z- ]# ?( ?" |& s7 u
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes6 F9 M$ v7 v6 j6 V
for each activity of each subject. The subjects are asked to perform the activ ( W: H' ?8 C; \5 Jities in their own style and were not restricted on how the activities should be6 Y+ H, u0 `9 L; h. O
performed. For this reason, there are inter-subject variations in the speeds and# p5 [0 j; B. Q+ x
amplitudes of some activities.$ P7 c! Z- k# {
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. 3 y& m* O; w, \The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal }9 v: R; X* ~( |! o7 u+ \: I
segments are obtained for each activity. - ?: @4 @: `4 l3 s( F. TThe 19 activities are: ! p& V4 S5 Q, l& v* P! V& h1. Sitting (A1);$ P4 d! I1 P' Z9 I# X+ m% h; M
2. Standing (A2); 3 k3 [1 B5 J! P& }/ q3. Lying on back (A3);8 X9 ?6 |! e7 ~4 G; j* \; e4 R" L
4. Lying on right side (A4); + c! z- ^6 Z# r i, A0 | }# d5. Ascending stairs (A5); 4 d4 l. \3 ]% x8 D& O16. Descending stairs (A6);2 W6 t$ D4 R& X$ ^# Y/ r$ c
7. Standing in an elevator still (A7);( O* T6 N9 F; f8 H4 _' ^
8. Moving around in an elevator (A8);' a2 f3 n+ I; p- c* e! N
9. Walking in a parking lot (A9); ! X V9 X7 h% D; G/ G& v9 J' U10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg : m" L$ B* f- [3 @' Sinclined positions (A10); , e" B; b6 j2 |* `; C" t11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions ) s0 O) J, b- ?4 `# X b; s# H(A11); # n3 i- M3 y3 I. F, U( s* N/ c12. Running on a treadmill with a speed of 8 km/h (A12); $ a6 w6 @3 g5 ] w, Y13. Exercising on a stepper (A13); 7 u* v2 M, O6 q2 F1 \3 Q# z14. Exercising on a cross trainer (A14); 8 C0 B( E6 S& K; i% O+ {0 y7 i15. Cycling on an exercise bike in horizontal position (A15); ! N. w; G' ?3 ^) D8 [16. Cycling on an exercise bike in vertical position (A16);; O' G G" ~6 V4 j' K
17. Rowing (A17); ! W' W, P b) R7 W# {4 {- p18. Jumping (A18);+ E7 Y* @& l' j: ^
19. Playing basketball (A19). / ?8 z/ G! X8 T+ D% H9 CYour team are asked to develop a reasonable mathematical model to solve7 V$ J" x6 H5 f1 J9 Y2 N0 @
the following problems.: U/ Z( U1 Q" v' w' \
1. Please design a set of features and an effiffifficient algorithm in order to classify$ Y6 m! A6 h/ _4 l( H" Q/ e
the 19 types of human actions from the data of these body-worn sensors.4 n9 a4 Z! B! A) H* N4 Q6 A
2. Because of the high cost of the data, we need to make the model have* s) f- G$ r; C5 A. H* Q5 ?. @$ h' Q5 H
a good generalization ability with a limited data set. We need to study 9 h% x! A, K! A3 l2 x5 Yand evaluate this problem specififically. Please design a feasible method to: k0 R3 a8 K1 l3 B) |
evaluate the generalization ability of your model. * N$ W/ ~8 y* I4 W8 X3. Please study and overcome the overfifitting problem so that your classififi- ! r1 I. N" {- Scation algorithm can be widely used on the problem of people’s action ! c0 c7 w4 y0 m6 A1 Uclassifification., l# p+ ]0 E* V) [/ J% |
The complete data can be downloaded through the following link:) v) G$ u/ @* C& D! @5 ?) V: [' i q) a
https://caiyun.139.com/m/i?0F5CJUOrpy8oq , H* n) [+ m- e: E' M. X2Appendix: File structure ; l, S" ~8 I0 g5 N% N( U) e$ p6 d• 19 activities (a) \. q; u5 R5 {5 M/ u8 m& l
• 8 subjects (p)% f m* m" `$ n* S% a) }& n1 O6 K
• 60 segments (s)% _1 h* z! P! N
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left# j/ u+ H7 u% d
leg (LL) # h4 F/ W! j& ? g f• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z ( H6 f* B, S! Lmagnetometers) X+ Z8 o0 J: Z/ p, d: I5 ?Folders a01, a02, ..., a19 contain data recorded from the 19 activities. $ D- e& h9 u' yFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the$ E4 b+ T/ n7 ]. H# P( ?$ b, n
8 subjects. # w5 y/ n- i2 b! hIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each0 g* Y4 @: ^8 z) r( f( ?
segment., L2 S2 D5 X4 X; P2 b. T
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 257 n" P# `: j3 U# y" |
Hz = 125 rows.4 G4 S5 E' l8 X( z9 V
Each column contains the 125 samples of data acquired from one of the ( \! _% _: k0 t! V( Nsensors of one of the units over a period of 5 sec.5 n4 h6 f+ B' \9 X' y" {% n' b
Each row contains data acquired from all of the 45 sensor axes at a particular& W0 h+ I: b- @% q$ _0 h+ c* V
sampling instant separated by commas.! u0 C( d e( ]! v8 z' ?1 B
Columns 1-45 correspond to: . w% s9 X/ [( y' D• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,. V, @( m7 E$ }. L
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, ( Y/ {# E7 w$ p+ c- _7 `$ ?• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag," ~$ B1 r* a* V+ ^: W
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, & E' J5 ]0 m% ]3 Z2 f• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. . p0 R6 A3 ~3 F& y; D; w3 _ }Therefore, : I, `" _0 N. c0 C+ B( q; V• columns 1-9 correspond to the sensors in unit 1 (T),' w2 A) O! T# a, Q; y* Q" C4 R
• columns 10-18 correspond to the sensors in unit 2 (RA), 6 s a2 I9 P+ E0 n9 U; G, r• columns 19-27 correspond to the sensors in unit 3 (LA), ) j' }( v+ I7 e# h• columns 28-36 correspond to the sensors in unit 4 (RL), 1 R8 K- v- A! x _• columns 37-45 correspond to the sensors in unit 5 (LL).1 h9 T" F3 v3 l: E3 b
3References* I% \8 I( a: G) e* E- Y1 c# k
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic ! {! Q+ N7 L9 q5 A2 Zdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.- ^" Q, b1 c; E
42(5), 679-687, 20042 ]' \/ @8 R% K1 m* e1 |
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of' T1 Z7 h5 }0 H; P
low-complexity fall detection algorithms for body attached accelerometers. C, ]: p H1 U8 a2 U) `
Gait Posture 28(2), 285-291, 2008 ] e8 q, R: {# N* }6 }7 v[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag3 Q" |- J( w$ B% y% I2 B# s$ v
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. 7 V% z8 E. i- W) cB. 11(5), 553-562, 2007 % J# t* a' E9 }4 C0 ]3 w[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con ( y* A6 R0 p8 u0 H5 Ltrol of a physically simulated character. ACM T. Graphic. 27(5), 2008 7 H$ y& Z/ H/ b, W. u ; o8 h8 ~. c8 c% h2022 , ^, ?9 m9 f$ I2 PCertifificate Authority Cup International Mathematical Contest Modeling " ?/ ]: D- w8 o) m2 D$ Chttp://mcm.tzmcm.cn& W. P0 B* D7 L9 I+ Q4 C
Problem D (ICM) / _8 y& ^- d* ^( C8 s9 W% o* oWhether Wildlife Trade Should Be Banned for a Long ; w8 o- j( }4 i/ j8 @; E- GTime " J2 m' @; ~/ S+ Y3 {4 lWild-animal markets are the suspected origin of the current outbreak and the9 l% D/ m# [, A" l- L) Y2 }/ Z0 m
2002 SARS outbreak, And eating wild meat is thought to have been a source1 C0 g& @; R- C# U9 k& z' d
of the Ebola virus in Africa. Chinas top law-making body has permanently0 D/ n$ G: u) y
tightened rules on trading wildlife in the wake of the coronavirus outbreak, : R* U, h& r5 b. ywhich is thought to have originated in a wild-animal market in Wuhan. Some 7 i' R2 H4 s9 @! v5 `% x bscientists speculate that the emergency measure will be lifted once the outbreak 8 s; f- z: L! I |- Zends. v6 ?6 W6 C7 o$ EHow the trade in wildlife products should be regulated in the long term? 9 N2 p& o0 h. J1 q; x6 tSome researchers want a total ban on wildlife trade, without exceptions, whereas1 f) _6 U. M% g. ^0 C9 d
others say sustainable trade of some animals is possible and benefificial for peo 7 E! b4 K0 q3 Y: ]/ [ple who rely on it for their livelihoods. Banning wild meat consumption could5 w# J2 f! t( z( m) o4 t, N
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil3 q7 r; l6 v1 s: I- e. j, h
lion people out of a job, according to estimates from the non-profifit Society of 7 S5 I+ U/ l2 X [+ NEntrepreneurs and Ecology in Beijing. 8 m9 X! {, Y, H% K- W$ gA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology$ y! J& K* e; h0 ^* X4 i0 b% l
in China, chasing the origin of the deadly SARS virus, have fifinally found their 4 O9 `0 U. K. Z4 m; W5 z* dsmoking gun in 2017. In a remote cave in Yunnan province, virologists have: V4 J6 j' P6 h& T1 a
identifified a single population of horseshoe bats that harbours virus strains with 9 s0 ~+ m" b; [7 E& [all the genetic building blocks of the one that jumped to humans in 2002, killing 4 M1 _, Q) c9 ~, W0 A: ialmost 800 people around the world. The killer strain could easily have arisen 3 ?) |, l% J9 m4 R( Dfrom such a bat population, the researchers report in PLoS Pathogens on 308 P4 N$ ?5 C& [* f+ n# p
November, 2017. Another outstanding question is how a virus from bats in . D* j) C& [) R8 DYunnan could travel to animals and humans around 1,000 kilometres away in $ O! @& L0 f3 h3 GGuangdong, without causing any suspected cases in Yunnan itself. Wildlife; k' _" v! A, i
trade is the answer. Although wild animals are cooked at high temperature6 H* g0 @7 i8 x9 P2 Q4 }6 { [1 X' n
when eating, some viruses are diffiffifficult to survive, humans may come into contact: [3 l" V# h' a
with animal secretions in the wildlife market. They warn that the ingredients3 a% t. P- Y. s( M7 k
are in place for a similar disease to emerge again. / l! U! N3 j! r: u3 k, ~6 t& q8 l1 IWildlife trade has many negative effffects, with the most important ones being:( k" l4 g7 Q- f& b4 _
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS . s( g6 |, A( u" u+ g' B. g4 Koutbreak in 2002.Credit: Matthew Maran/NPL & `. Y+ a: @( N0 }% K2 Z9 y• Decline and extinction of populations " Q5 j% z* E( D' _ r, {• Introduction of invasive species ' K% y8 B' n& L' c) J• Spread of new diseases to humans, Y; f1 A* S, O; K6 g+ X
We use the CITES trade database as source for my data. This database* p5 P% j h8 S! }: ] X
contains more than 20 million records of trade and is openly accessible. The5 ]8 |; l( V, m" A- j; i8 L
appendix is the data on mammal trade from 1990 to 2021, and the complete ! Z4 ?' J( a7 k4 |database can also be obtained through the following link: $ T3 k9 K6 j1 [! I2 ~https://caiyun.139.com/m/i?0F5CKACoDDpEJ 0 L, N* o, ]7 V6 o4 z3 Y& jRequirements Your team are asked to build reasonable mathematical mod 6 q1 O) Q& c- R. lels, analyze the data, and solve the following problems:2 e1 y( h2 V8 K" ?' O |
1. Which wildlife groups and species are traded the most (in terms of live% N) g0 P0 }: I- @% }1 q$ [. S
animals taken from the wild)? $ p7 T4 x) I1 J, s* w2. What are the main purposes for trade of these animals?& a A4 W7 u S, Y; x- F* M
3. How has the trade changed over the past two decades (2003-2022)? 6 X% W/ x/ H6 ~ t4. Whether the wildlife trade is related to the epidemic situation of major : F+ @% o0 w* z& B7 S8 c* Kinfectious diseases?8 u- d; [) @8 x+ W
25. Do you agree with banning on wildlife trade for a long time? Whether it * A$ [7 o5 K+ l) S2 K J! W* dwill have a great impact on the economy and society, and why?2 g$ [# ] y7 D+ W# P0 X
6. Write a letter to the relevant departments of the US government to explain! v& R( |* D5 q# }
your views and policy suggestions.( S# k A; E% l7 F. c2 v5 K' E
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