2022小美赛赛题的移动云盘下载地址 . ~! `& v" B- P1 Ihttps://caiyun.139.com/m/i?0F5CJAMhGgSJx ) X- e6 w8 b8 ~/ @ 3 j. I0 B# V8 P2 N4 R A: M2022 + r/ }1 d$ c! z- X+ oCertifificate Authority Cup International Mathematical Contest Modeling" o$ e3 }* ]2 X4 F/ w/ l+ {
http://mcm.tzmcm.cn( Y8 f. O* l# X" Y/ V
Problem A (MCM)" E3 @- h) C5 u& L& \
How Pterosaurs Fly, |) c2 c; i Y1 b
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They" {: V; M# B" ~2 X( G v
existed during most of the Mesozoic: from the Late Triassic to the end of5 J X( u- k& f: _+ o1 F3 v1 M
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved& |! O3 o9 {% a: b: k
powered flflight. Their wings were formed by a membrane of skin, muscle, and 8 H8 a: s; V/ p; J0 zother tissues stretching from the ankles to a dramatically lengthened fourth $ v) G& O6 q0 m; F, @fifinger[1].# A; t/ x! E1 R, ^. f) j) J
There were two major types of pterosaurs. Basal pterosaurs were smaller. r# D' k z3 p. o1 f" e b
animals with fully toothed jaws and long tails usually. Their wide wing mem7 {( \& K' I: _$ F X- h, b
branes probably included and connected the hind legs. On the ground, they 8 p8 P' U8 |0 Y) C7 B' b: Kwould have had an awkward sprawling posture, but their joint anatomy and& x% [) Y. W( q0 z/ }6 }. U6 L
strong claws would have made them effffective climbers, and they may have lived7 w% b4 v1 Y. |7 i; g* z6 [
in trees. Basal pterosaurs were insectivores or predators of small vertebrates.* Q4 }# z9 b% j: r* @7 b( a* W
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. / n( Q/ h# G, Z, o6 O9 }, ?Pterodactyloids had narrower wings with free hind limbs, highly reduced tails, / M! x: H! r( l5 I2 W, }and long necks with large heads. On the ground, pterodactyloids walked well on 4 j0 V& u0 s# n, d. \all four limbs with an upright posture, standing plantigrade on the hind feet and 3 H$ \1 M6 ] n2 Zfolding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil 8 b8 r' e' I% q/ p( `) Utrackways show at least some species were able to run and wade or swim[2].2 O5 W4 Q1 G- b' r; ?7 `! E$ [
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which % p+ C+ i5 H( q. r2 tcovered their bodies and parts of their wings[3]. In life, pterosaurs would have9 m+ I5 _# E8 L8 \" A& ^) x* y
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug$ ` X7 X7 | d& [
gestions were that pterosaurs were largely cold-blooded gliding animals, de3 v' h3 i" g; M) t
riving warmth from the environment like modern lizards, rather than burning4 a$ y d& i, s. v3 p$ m
calories. However, later studies have shown that they may be warm-blooded$ {2 P1 l' ~5 b
(endothermic), active animals. The respiratory system had effiffifficient unidirec ! m, b# i) w5 _% ntional “flflow-through” breathing using air sacs, which hollowed out their bones; k; v0 T9 r; W! {" s0 S, h6 K
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from% R% O7 m' G! a4 n: q
the very small anurognathids to the largest known flflying creatures, including$ s# d* V9 i) x, A
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 9 S$ H+ t/ s: ~5 Unine metres. The combination of endothermy, a good oxygen supply and strong X3 ^* B/ N+ O0 d
1muscles made pterosaurs powerful and capable flflyers.3 N5 c6 T, C/ c
The mechanics of pterosaur flflight are not completely understood or modeled0 g1 b3 w9 j9 e* A w/ A2 C
at this time. Katsufumi Sato did calculations using modern birds and concluded; W4 A8 l6 k V' P6 U) x. n
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,3 V5 J; L5 j4 S4 S: p( {
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able) h) T u5 \& O' Y
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].5 j$ x: L+ I% @% T; s& x
However, both Sato and the authors of Posture, Locomotion, and Paleoecology! K8 g5 ~' Z% C; D0 y
of Pterosaurs based their research on the now-outdated theories of pterosaurs' B+ @& q2 m* V1 D
being seabird-like, and the size limit does not apply to terrestrial pterosaurs,8 w8 c! k" A! E- P9 U9 X
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that $ l3 K' w% q* F catmospheric difffferences between the present and the Mesozoic were not needed, y7 E1 c6 _2 A
for the giant size of pterosaurs[8]." R2 g8 u. u$ X9 U
Another issue that has been diffiffifficult to understand is how they took offff. 1 M2 z' v5 t( o0 DIf pterosaurs were cold-blooded animals, it was unclear how the larger ones. @+ n8 S# l8 [
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage |" ?$ B; Z, E( X$ W5 Fa bird-like takeoffff strategy, using only the hind limbs to generate thrust for- o9 O1 g0 Y6 d; O' E) I
getting airborne. Later research shows them instead as being warm-blooded& \2 Y& c0 t D0 ]
and having powerful flflight muscles, and using the flflight muscles for walking as . J- c7 @ t4 M9 o. W9 e) Hquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of " U" q4 H7 l& W" Z) ?. ~3 n' IJohns Hopkins University suggested that pterosaurs used a vaulting mechanism ) \7 Q0 j2 ?" L0 I) N4 Lto obtain flflight[10]. The tremendous power of their winged forelimbs would : F/ {3 j. G4 _* t2 D# \2 e! p% \enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds , i( b) K! o. \! j# P( f( Y- Tof up to 120 km/h and travel thousands of kilometres[10]. # t: [5 h# T+ @+ aYour team are asked to develop a reasonable mathematical model of the t" Y$ O9 Q% pflflight process of at least one large pterosaur based on fossil measurements and % X" {0 O; {" D/ z4 R! Vto answer the following questions.& L9 o, J9 G0 A3 Y5 J& \1 A+ Z
1. For your selected pterosaur species, estimate its average speed during nor( b; X. \. ^9 b$ F, Y" u
mal flflight.+ r1 k4 e8 z" J5 z" N; m4 m1 O8 j
2. For your selected pterosaur species, estimate its wing-flflap frequency during/ B- D1 R/ w9 M8 A
normal flflight.9 Z( H& Q z4 A7 ]5 F V9 W1 }
3. Study how large pterosaurs take offff; is it possible for them to take offff like 1 p" x/ h* [! a9 E4 B0 wbirds on flflat ground or on water? Explain the reasons quantitatively.. P! U8 N( S0 z
References - D1 d7 K) l$ @6 O, f6 i[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight ) b5 F' b; e. e9 l+ i7 ~0 E( w! yMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111. 2 q1 d& S$ w* P6 C2 S2[2] Mark Witton. Terrestrial Locomotion.7 I$ J8 i, U7 U+ h) W% Q4 @. j
https://pterosaur.net/terrestrial locomotion.php 9 Q* B$ j+ D+ v1 i1 a. \[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs, r+ T- v+ e3 F0 @7 R$ o8 |; w4 Z1 u
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324- + s2 l% c9 q5 lpterosaurs-had-feathers.html$ s2 w. O1 R$ U$ r G7 w. w$ r
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a 9 q3 `, f8 Y0 f1 j Mrare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)3 @ ?/ B) z) D8 C3 U7 _# b
from China. Proceedings of the National Academy of Sciences. 105 (6): - g3 Q7 W% b. d, ^0 j) e1983-87.3 m) z! s5 y. w2 R1 \( f
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust/ _) I/ d# s4 ~ E5 b$ T( a' M
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4): * q/ R9 `1 b: c9 O( t6 T$ O# x180-84.+ R9 o7 {. F# S5 D
[6] Devin Powell. Were pterosaurs too big to flfly? ) S5 O S. V1 B7 nhttps://www.newscientist.com/article/mg20026763-800-were-pterosaurs2 Z; N' R" j8 }; \' ^, l
too-big-to-flfly/5 ~" g/ n! E9 D% R
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology T9 w5 q: Z# t* S8 i$ R
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. ) z2 \* G; m( N7 _0 o: c* b[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable: j* \' ]. z M" ~" Q
air sacs in their wings." \' P5 q6 M- ]! ~4 t6 [+ p Z* \
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur+ y$ d7 q8 `6 l
breathing-air-sacs . r2 r0 O) u1 F' D[9] Mark Witton. Why pterosaurs weren’t so scary after all., z7 K$ g5 ^9 u" B7 L6 Q; D
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils1 B* T, C1 t3 O! z
research-mark-witton9 c( T+ }" d* P; h
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 9 K6 A( ?* j0 L$ @" ~- B! S0 zhttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs$ @6 h# [2 H' L; N: V
vault-aloft-like-vampire-bats/: j' L8 W% v) j
{: f5 `% [$ u1 \/ e
2022, U3 s) \1 @% P5 |; o
Certifificate Authority Cup International Mathematical Contest Modeling" L( k4 e' q, S
http://mcm.tzmcm.cn " d+ U# p/ u/ P$ }; RProblem B (MCM) N! ]( a' C& T$ W" O( @; s9 qThe Genetic Process of Sequences : P( C$ o9 u9 S4 c, N; |Sequence homology is the biological homology between DNA, RNA, or protein 0 Q! P% i3 ~) t d9 h, T ksequences, defifined in terms of shared ancestry in the evolutionary history of 4 l3 W$ ?0 c/ Zlife[1]. Homology among DNA, RNA, or proteins is typically inferred from their' A8 f# f- k s. K7 _! a- w: T6 X
nucleotide or amino acid sequence similarity. Signifificant similarity is strong: E- H& H" z* N! E
evidence that two sequences are related by evolutionary changes from a common2 n& W, |/ {; Q' |& P/ m# R+ g
ancestral sequence[2].3 f2 g: p- K; P" F) R$ S
Consider the genetic process of a RNA sequence, in which mutations in nu6 r" X0 \$ v' D6 [" t C
cleotide bases occur by chance. For simplicity, we assume the sequence mutation6 A2 R( }; R- q! y8 ~
arise due to the presence of change (transition or transversion), insertion and $ D2 Y4 g0 n% p* u+ {" z4 Ldeletion of a single base. So we can measure the distance of two sequences by/ k: f0 e% }& H7 t% ]' U
the amount of mutation points. Multiple base sequences that are close together& A7 N& S/ G) R& H, n
can form a family, and they are considered homologous.5 z" P1 e5 m' z+ A9 ~6 N
Your team are asked to develop a reasonable mathematical model to com3 M4 f$ Q7 C/ G' ^, \
plete the following problems.: i" G& \! I. D% a: V
1. Please design an algorithm that quickly measures the distance between1 Z2 W& G7 k% n1 t* ]' I' y
two suffiffifficiently long(> 103 bases) base sequences. ; |1 W, t) f! v& n% U; x2. Please evaluate the complexity and accuracy of the algorithm reliably, and, ]; o: h* ?/ r" W
design suitable examples to illustrate it. $ U$ q( U- n* N; s8 ]" ^: e3. If multiple base sequences in a family have evolved from a common an8 h* D8 N% P0 f$ A' k
cestral sequence, design an effiffifficient algorithm to determine the ancestral " ?: x) k; ]7 I4 T" f/ i7 ksequence, and map the genealogical tree. # l" y' b# x+ ]References ( i' d- q5 L# p5 H[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re' G, E% V& v9 I6 [( Y) O; A4 X7 l& K
view of Genetics. 39: 30938, 2005.+ n6 ~( U; ?( g: t) v/ v/ y5 n
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, ; a- c; ^ ?4 ?# s4 get al. “Homology” in proteins and nucleic acids: a terminology muddle and . `+ M3 j! Y, B( \+ N$ h6 ?a way out of it. Cell. 50 (5): 667, 1987. 3 e& y- {, y' ?$ Z : J C u# G4 X4 i- A% `# r0 \2022 - u& c) }+ C/ N3 C T+ h6 UCertifificate Authority Cup International Mathematical Contest Modeling : K+ `& X0 S9 ?# a( U; o4 T) q2 [http://mcm.tzmcm.cn2 E4 ]8 ^& U' W, m) }
Problem C (ICM) + @* m) v8 q, c! ~& aClassify Human Activities 0 [& c9 S% H* d1 E; r6 }% @) AOne important aspect of human behavior understanding is the recognition and" A2 U7 {0 n- O0 ^! [: [
monitoring of daily activities. A wearable activity recognition system can im- ]# r) i. E8 {; s* Y; J# n( `
prove the quality of life in many critical areas, such as ambulatory monitor 1 G+ x2 G" S6 U5 s2 q) Ping, home-based rehabilitation, and fall detection. Inertial sensor based activ' w8 e( N1 a2 L1 ^/ T: E& E2 A% r
ity recognition systems are used in monitoring and observation of the elderly ' Q7 P7 G% }+ nremotely by personal alarm systems[1], detection and classifification of falls[2], " {) W1 b; D6 J9 ymedical diagnosis and treatment[3], monitoring children remotely at home or in6 v& e; q |0 H
school, rehabilitation and physical therapy , biomechanics research, ergonomics, + ]: {& l2 [+ K! v, U6 L* ~& |# qsports science, ballet and dance, animation, fifilm making, TV, live entertain8 G- \6 ?! ]) r3 w( m) y4 N9 @. G- K5 J
ment, virtual reality, and computer games[4]. We try to use miniature inertial# O9 H! v: `! _0 G/ ~' j r
sensors and magnetometers positioned on difffferent parts of the body to classify- v0 {' E6 N8 y4 |. J) u
human activities, the following data were obtained. : x- H$ T% n# E: f8 UEach of the 19 activities is performed by eight subjects (4 female, 4 male, 1 n5 b6 n1 u* O' O: u5 Abetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes, E J2 ?$ q0 F1 ]
for each activity of each subject. The subjects are asked to perform the activ % C. Y" ^5 j2 R. Wities in their own style and were not restricted on how the activities should be 6 ?' S" N* D4 [3 w! jperformed. For this reason, there are inter-subject variations in the speeds and8 X5 `- l! U( f# L# e& J
amplitudes of some activities., T7 [' a5 J, j/ q% z8 i/ u7 L
Sensor units are calibrated to acquire data at 25 Hz sampling frequency.( p- R. X5 ^( M5 b
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal 1 c# q1 }2 ~8 u3 w+ t3 {, \segments are obtained for each activity.; {: k& e1 W) U& k' Z- [9 }
The 19 activities are:9 S; f0 c8 Y; x+ J/ N9 U2 j
1. Sitting (A1); / g4 p- Y" N x/ j* ~9 o; k/ x' v# i2. Standing (A2); # D# p; B7 s2 [; R8 h3. Lying on back (A3);( Z% r7 E0 y- z0 A, M4 c, X
4. Lying on right side (A4);% A3 Z. z, w! [& i
5. Ascending stairs (A5);* r4 R' P6 ?- L( I! L
16. Descending stairs (A6);5 d* q' [% m6 u- M# S
7. Standing in an elevator still (A7);: X0 H* r7 h: G
8. Moving around in an elevator (A8);. j2 T+ a+ y0 m7 m+ A T
9. Walking in a parking lot (A9); $ ?( W. a3 J, x0 m m' L10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg 4 p5 Z! t6 ?5 linclined positions (A10); / \/ X. j: ~0 T* P; ?11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions . F! Y9 o: s& p+ h- @+ ^(A11); 0 ?# [: j I( O5 U. \9 C: _12. Running on a treadmill with a speed of 8 km/h (A12); . G1 R( t! G. B" s' |! o. R9 J13. Exercising on a stepper (A13); : \. U% O2 Z; M: K: R' x& F14. Exercising on a cross trainer (A14);7 }& P N* {' F
15. Cycling on an exercise bike in horizontal position (A15);& D/ H1 W L# l* Z0 P6 E: Q7 }: s
16. Cycling on an exercise bike in vertical position (A16);9 \& h0 \2 R F; O5 r6 {' ~
17. Rowing (A17); . ~9 |! c/ d- U, F& W# k18. Jumping (A18);1 j" g# R2 }: z3 O
19. Playing basketball (A19). 8 u! b2 K* f( e5 T5 Q% k+ j! E# i& N& \Your team are asked to develop a reasonable mathematical model to solve 1 d' I. h) {. ~# J% k8 M6 [9 h+ cthe following problems.0 Q t0 R( B1 U2 s& P9 d
1. Please design a set of features and an effiffifficient algorithm in order to classify ) U) p6 d1 F. r4 X8 o4 mthe 19 types of human actions from the data of these body-worn sensors.1 p9 P5 F' E; ~+ v6 w* l! G
2. Because of the high cost of the data, we need to make the model have7 z( N) U! u( [5 f3 U
a good generalization ability with a limited data set. We need to study4 W; J& b: u! r" r6 Z9 e
and evaluate this problem specififically. Please design a feasible method to . ?( o" H8 K. o5 M, Q9 W( Y uevaluate the generalization ability of your model. 4 l/ U2 D- h. ~3. Please study and overcome the overfifitting problem so that your classififi-4 e/ O7 T' b2 w2 I! L0 s; }
cation algorithm can be widely used on the problem of people’s action& m/ z5 \$ q% ]' e
classifification. ! E" b/ [2 z MThe complete data can be downloaded through the following link:' w& c) @, }& Y3 M
https://caiyun.139.com/m/i?0F5CJUOrpy8oq, v& m; L J3 p3 t6 u
2Appendix: File structure $ ^$ X5 A" g- q c6 }• 19 activities (a)0 x) R& }: j I- k& Y
• 8 subjects (p) ( X$ D; l$ X; H. J) J' A• 60 segments (s)% r2 m) f% b0 ~6 j
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left ( _! a' g$ r8 \4 F4 k7 y4 p- j% }6 hleg (LL) 6 w1 l* n" u3 f+ L* S+ v0 k• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z + g0 l- s' Y4 Tmagnetometers) ; P2 f& e+ S( D- \' a9 nFolders a01, a02, ..., a19 contain data recorded from the 19 activities.0 k9 W' h! M! Z: o6 V
For each activity, the subfolders p1, p2, ..., p8 contain data from each of the 3 \ I$ O n8 n( P1 _9 t, Z8 subjects. # g( }3 d6 n6 m5 Q9 ^, E1 UIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each) D8 a/ y* C8 m) v; d
segment. % a4 w- d2 k+ F( W+ f& NIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25- K! ?3 f; g2 K* }" I6 u
Hz = 125 rows.; F" V) X. `+ v# N: f% W, `
Each column contains the 125 samples of data acquired from one of the; M% L' e! ^9 q$ @; |" ]& P0 ?* M' b) ~
sensors of one of the units over a period of 5 sec. 2 m2 S4 u) F- f% _* N: E; z6 I0 PEach row contains data acquired from all of the 45 sensor axes at a particular ) ^; F; y$ s) ~* f6 [4 {/ lsampling instant separated by commas. 9 _4 a0 F) P- YColumns 1-45 correspond to: 7 s% p: `; Z0 \! D0 |% S$ E• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,. \" p: y; i" j5 j2 P: A1 ~8 @
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,' C9 m1 n" R9 u
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag,2 K( y0 D4 d& }5 i
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, 1 e( z8 z- C. j- k8 {• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.+ ]- L( U: L4 ?
Therefore,0 {* Y8 z7 l) u
• columns 1-9 correspond to the sensors in unit 1 (T),3 ?4 c% c! W7 B. E/ u* n
• columns 10-18 correspond to the sensors in unit 2 (RA),/ R$ }5 C: G9 N9 d7 v$ |
• columns 19-27 correspond to the sensors in unit 3 (LA),# } h4 m- p( U+ C$ ]
• columns 28-36 correspond to the sensors in unit 4 (RL), ; \& I( o! y) _8 M0 n• columns 37-45 correspond to the sensors in unit 5 (LL). B" O* T" j- C3 |1 }8 A- s
3References$ K+ P) E0 x5 W; b, r
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic $ a+ o* H$ Y0 Y( rdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. : `( M2 t6 @# ?$ Z% F42(5), 679-687, 2004 / {8 Z' M( H/ ?! k* K[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of ) F: B% S& D! R: jlow-complexity fall detection algorithms for body attached accelerometers.! [' L- ^, d7 `1 f" i, L
Gait Posture 28(2), 285-291, 2008 0 j2 q5 @9 A4 U, f1 ?[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag , r3 h7 H+ t+ f# { Vnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. 2 H, u. V* M3 TB. 11(5), 553-562, 2007 / [1 Q- Y4 H- [- C8 J[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con0 h' d) a- z' b1 G% I5 \/ z: Z
trol of a physically simulated character. ACM T. Graphic. 27(5), 20089 g+ {3 |0 q4 `3 w$ ~
0 d6 k* |0 @8 Q: G4 C! R; f
2022, r8 ^; z4 {6 Y( z, h
Certifificate Authority Cup International Mathematical Contest Modeling8 O! t4 h$ {7 L' J5 F& B6 X
http://mcm.tzmcm.cn 0 d+ R) H! i4 k( ~& qProblem D (ICM)6 Z, c- m; O0 D
Whether Wildlife Trade Should Be Banned for a Long0 g3 w8 u3 i0 F/ E/ c2 q
Time$ h3 |& x6 W% ?9 Q& N
Wild-animal markets are the suspected origin of the current outbreak and the * I% @) J/ I; s4 X2002 SARS outbreak, And eating wild meat is thought to have been a source 6 j1 p7 w# H; K& g9 _of the Ebola virus in Africa. Chinas top law-making body has permanently 7 u* [# y* O" u( w2 \: i& R; t/ |tightened rules on trading wildlife in the wake of the coronavirus outbreak, 5 [( E, R( y- Mwhich is thought to have originated in a wild-animal market in Wuhan. Some1 Q% |" L/ r- ]! ~
scientists speculate that the emergency measure will be lifted once the outbreak# Q" y- H) ~3 \/ t
ends.& u- L) Z3 b9 J3 l3 C$ i2 v( C
How the trade in wildlife products should be regulated in the long term?! W {' f! z1 w
Some researchers want a total ban on wildlife trade, without exceptions, whereas7 Q4 q" G& T' p
others say sustainable trade of some animals is possible and benefificial for peo' y8 t3 v4 J$ w V( U5 P6 B% X1 V- G
ple who rely on it for their livelihoods. Banning wild meat consumption could6 J5 b9 x0 f( h, H9 E% b* Z
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil$ F8 J* x+ _9 o$ k9 D
lion people out of a job, according to estimates from the non-profifit Society of ' i W7 @0 n2 o( X# X* B; |Entrepreneurs and Ecology in Beijing.9 N( @' l, J+ T9 |) O/ n* I9 t( b
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology * B. H# q ?! q7 r3 ein China, chasing the origin of the deadly SARS virus, have fifinally found their4 ] u8 M! M: P1 ^, B% d8 d
smoking gun in 2017. In a remote cave in Yunnan province, virologists have # ^/ H* M1 X) w) s# k5 `identifified a single population of horseshoe bats that harbours virus strains with) J" @8 \% C2 d, x) P7 c9 d2 a8 m, t
all the genetic building blocks of the one that jumped to humans in 2002, killing x6 Q* A2 T, W Y: U& d$ ]
almost 800 people around the world. The killer strain could easily have arisen' e4 P9 [+ ]# B8 T; Z8 [$ S- Z
from such a bat population, the researchers report in PLoS Pathogens on 30+ k( w7 Z1 Y5 ~ X
November, 2017. Another outstanding question is how a virus from bats in 8 j% Q5 N- @' `* u PYunnan could travel to animals and humans around 1,000 kilometres away in$ p7 z. ?2 a! z7 M; T
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife% b' E" D& Y8 x& t& e
trade is the answer. Although wild animals are cooked at high temperature 6 v: P0 f$ }5 }) Y5 |when eating, some viruses are diffiffifficult to survive, humans may come into contact ' Y* {% T) q0 A' L0 H2 u* h1 P) ]with animal secretions in the wildlife market. They warn that the ingredients8 K( N1 \' n. g( P
are in place for a similar disease to emerge again. , r% P. h2 Y/ b& F: j' LWildlife trade has many negative effffects, with the most important ones being:; f8 B2 p; X' ?2 y! t
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS v: j. T$ v# H9 L2 [- I+ G
outbreak in 2002.Credit: Matthew Maran/NPL 0 w: b1 y6 z+ Z* Z+ B/ H9 w% D+ L• Decline and extinction of populations ! n# t+ H8 Y& g* w. M, y& `5 ]) Y• Introduction of invasive species8 Z9 p; h2 n1 L/ w
• Spread of new diseases to humans ) W5 n. E" s7 I- h$ f+ yWe use the CITES trade database as source for my data. This database ( Q8 K$ A" D; Y( ?contains more than 20 million records of trade and is openly accessible. The! ]" d2 J$ ~' C4 c i Q8 c% X6 z& c
appendix is the data on mammal trade from 1990 to 2021, and the complete; u/ X/ h& \/ q- C5 O1 F
database can also be obtained through the following link: $ l/ k; S& U: [7 thttps://caiyun.139.com/m/i?0F5CKACoDDpEJ / E% n' {& ^: |- dRequirements Your team are asked to build reasonable mathematical mod ; P& d; Z7 G2 p7 u5 [/ n# \els, analyze the data, and solve the following problems: / o! Q+ [: N( G, p7 n/ n1 d1. Which wildlife groups and species are traded the most (in terms of live 5 g8 i* d! g( P0 L7 j. P6 Oanimals taken from the wild)?# Y) h1 D2 s/ K1 [6 n
2. What are the main purposes for trade of these animals? . g$ y% @, M' E3. How has the trade changed over the past two decades (2003-2022)?9 V7 q1 B7 o+ ^
4. Whether the wildlife trade is related to the epidemic situation of major / x! U3 q/ V; h! m7 \9 Kinfectious diseases? ' ^9 U# a# }% m# k# @) {' U' j25. Do you agree with banning on wildlife trade for a long time? Whether it $ j0 V2 M$ c/ y: j* q2 ^+ xwill have a great impact on the economy and society, and why?- ^; a: f, ^( n! l' Y1 U# f
6. Write a letter to the relevant departments of the US government to explain ; g p0 }0 j. x* Q. m+ O1 ayour views and policy suggestions. ( B, c3 v0 m ~5 | a0 z$ e" Y: R9 d : f& a" \: X+ B4 |+ q3 b3 f " |1 v* i3 l" N' D2 w/ ~. c8 M& ^. K) A8 V# R8 X+ C- B
* s1 k9 n# _6 c
8 X1 f. Z+ Q. E( y+ ?
- R) }1 Y, { }: y1 R Z 2 o% z; D* F7 e3 Q4 V$ w+ ~