2022小美赛赛题的移动云盘下载地址 7 Q- _" C: }( r0 v
https://caiyun.139.com/m/i?0F5CJAMhGgSJx* F2 ?' @+ `( q q- \+ z- P
; b% L1 F, t! P( g$ x
2022, D0 G K7 V. c0 T; ]$ l
Certifificate Authority Cup International Mathematical Contest Modeling0 m. u7 A! ?, S& G$ l
http://mcm.tzmcm.cn$ P, c/ {5 G8 Y. [/ O" Q
Problem A (MCM)& A: c) u. ?8 [( c4 i
How Pterosaurs Fly, E- x1 j7 l+ Z9 ]; M, w0 U: M
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They & a7 f7 i0 O6 }existed during most of the Mesozoic: from the Late Triassic to the end of8 b* A. w+ O- j3 o: U. o* ^) N
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved9 Q$ b3 {0 C6 o$ H
powered flflight. Their wings were formed by a membrane of skin, muscle, and " i1 t+ F! v1 {( k+ t$ T; Lother tissues stretching from the ankles to a dramatically lengthened fourth , k' w* d g) |* w( X: ^/ qfifinger[1].3 ^) R2 |; t* a- Y/ b% m+ i
There were two major types of pterosaurs. Basal pterosaurs were smaller ; s+ w8 ~: B/ I+ \! kanimals with fully toothed jaws and long tails usually. Their wide wing mem . n. H" W% Y, y7 x9 `7 b% gbranes probably included and connected the hind legs. On the ground, they , W( I w7 s0 F! \# @would have had an awkward sprawling posture, but their joint anatomy and2 a7 x; e# G6 }4 x' ^$ r+ A, z% {
strong claws would have made them effffective climbers, and they may have lived; s! M4 M o) B5 W% s# v+ {1 k
in trees. Basal pterosaurs were insectivores or predators of small vertebrates. / L3 U: @- C! T% y% p0 lLater pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. 3 i) N1 ^ I. A3 @" S$ |2 s3 a, T; ]Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,- F/ [% C6 }6 @6 v% z6 {
and long necks with large heads. On the ground, pterodactyloids walked well on( [! Z% ^' Q" S6 B
all four limbs with an upright posture, standing plantigrade on the hind feet and , a- C H/ J2 ?folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil ! r% e9 E% H* C; g& }! }trackways show at least some species were able to run and wade or swim[2].4 }. d0 A4 w O4 m+ C0 [& l
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which3 U; D5 i; O- `* e) S
covered their bodies and parts of their wings[3]. In life, pterosaurs would have- J# d' ]1 v7 S( Q. a
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug . m3 K3 C, ]; g3 \ C. cgestions were that pterosaurs were largely cold-blooded gliding animals, de1 {7 Q p, y" J3 z/ d
riving warmth from the environment like modern lizards, rather than burning . S1 @9 ]( f* |* Y1 @calories. However, later studies have shown that they may be warm-blooded0 [8 d3 X5 }1 r
(endothermic), active animals. The respiratory system had effiffifficient unidirec 5 ~) O; [7 d+ ]tional “flflow-through” breathing using air sacs, which hollowed out their bones) M" H: R, J! W6 J5 T/ G9 H U6 G
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from . I3 G5 F5 x' L6 ^( d' ethe very small anurognathids to the largest known flflying creatures, including5 Y. x+ K6 Y+ ?/ w9 t. e+ f/ l
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least ( f& Y4 `+ h T! ^% Q |2 Lnine metres. The combination of endothermy, a good oxygen supply and strong! a5 m: Y u: S5 l
1muscles made pterosaurs powerful and capable flflyers. 1 _. O4 | z3 }6 x5 AThe mechanics of pterosaur flflight are not completely understood or modeled5 f( H( }2 a, Q' P9 z
at this time. Katsufumi Sato did calculations using modern birds and concluded 9 ?, V: ]% y% r+ lthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture, & X$ m1 m6 W) n7 M7 T) u0 W/ TLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able & {+ m5 O+ `5 O) Cto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. U( i: Q8 {6 _& L7 T
However, both Sato and the authors of Posture, Locomotion, and Paleoecology2 U6 U) Y7 X+ {" A+ S4 h4 ?8 ^
of Pterosaurs based their research on the now-outdated theories of pterosaurs 4 o' E4 p4 @0 y% T) ]" G4 k6 nbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs,3 b! \# V+ \, t, j, u9 Z
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that" \. h Q. V* b$ S7 F
atmospheric difffferences between the present and the Mesozoic were not needed5 f+ j9 d5 ^9 T6 U! a
for the giant size of pterosaurs[8].( n# i% d( h4 \7 @
Another issue that has been diffiffifficult to understand is how they took offff. $ z9 `+ i" Z1 T- c4 ]& vIf pterosaurs were cold-blooded animals, it was unclear how the larger ones 5 _& a$ }: V3 M6 Q/ W* jof enormous size, with an ineffiffifficient cold-blooded metabolism, could manage ' p- N7 Z# k( ca bird-like takeoffff strategy, using only the hind limbs to generate thrust for7 q' w ~( I& s2 S: x' {
getting airborne. Later research shows them instead as being warm-blooded! h3 e4 h/ Y3 v2 V3 v
and having powerful flflight muscles, and using the flflight muscles for walking as ) W4 s( c2 J- t2 G% |quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of k, }2 K2 m7 D! s: q, y
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism * w$ m% T! q5 P+ h0 Z& t2 t1 pto obtain flflight[10]. The tremendous power of their winged forelimbs would- u, J* z1 c k8 g) v! c/ s9 b
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds* Q- m2 L+ v G' e
of up to 120 km/h and travel thousands of kilometres[10].& o( K* ]* C% N+ s- Q# F
Your team are asked to develop a reasonable mathematical model of the ! v" s! J7 w0 B! j! rflflight process of at least one large pterosaur based on fossil measurements and$ m. l$ o8 Y, i- w
to answer the following questions. " h2 n9 V* ]/ ^+ i/ g1 Z1 o- [1. For your selected pterosaur species, estimate its average speed during nor: _( u9 h9 @) I+ f- T
mal flflight. ; d9 U: X2 @# d) q4 l) Y8 q! u2. For your selected pterosaur species, estimate its wing-flflap frequency during - _ h& _1 a( I1 ^( Onormal flflight.* q. K1 u! M, G6 L" a- _2 @, s" V9 D
3. Study how large pterosaurs take offff; is it possible for them to take offff like# v6 \6 m8 w$ ~" J; E
birds on flflat ground or on water? Explain the reasons quantitatively. , k6 g4 R* B1 X FReferences 8 G# C$ N% P A0 C- s% H, O[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight 1 c, E: {" o/ L% E- yMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111.( f8 A G% I$ }# N
2[2] Mark Witton. Terrestrial Locomotion. 0 w/ q! u9 C$ E& m( N$ q. bhttps://pterosaur.net/terrestrial locomotion.php ( K) t/ b, ~# S- ?& u! i9 P! \, A+ d[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs1 r2 V" W6 w L) c
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324- - f( `* \; \ O2 w: F+ b; Vpterosaurs-had-feathers.html% k4 Y" y L! m" u
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a9 h o- Y" A; a% X
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea), c7 U) J/ u7 c
from China. Proceedings of the National Academy of Sciences. 105 (6):$ I/ v! n: t5 x* Y% h* z
1983-87.* ^1 ]+ N( G* w% a
[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust1 P9 Q8 o/ G" @0 D4 E; H6 \2 |
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):( d) d+ o# Z$ ^2 X5 ~
180-84. # u8 g; w% y# t L1 B[6] Devin Powell. Were pterosaurs too big to flfly?" {- f- `$ C2 _3 v
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs * j, Y& F$ u) f, {. Stoo-big-to-flfly/ 6 c1 V& q# [5 v- D8 ^% O- _[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology" m* |( u8 u9 q7 ^
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. 9 `" \9 ~: |- y' D[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable 5 b! d/ u8 m& i7 Q D3 ?1 f$ qair sacs in their wings. q4 c0 ]& Q8 T2 `' v# dhttps://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur 6 M8 `, X& |$ m, D. k' i) pbreathing-air-sacs # r& F1 B; ^7 F: ~. Y& t7 I- ^[9] Mark Witton. Why pterosaurs weren’t so scary after all. 7 E, R5 Z+ y0 E( _6 i5 Rhttps://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils 3 Z2 d' V0 E7 u! z( i; hresearch-mark-witton* x9 Y$ J4 ]' g+ u6 X7 B0 `
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? % Y% D* ?. R# K! K6 M7 `https://www.newscientist.com/article/dn19724-did-giant-pterosaurs' |' m3 u! ~* u
vault-aloft-like-vampire-bats/- m; C. `/ U) d) a7 F" N6 A
' ]+ I E5 o% _$ h9 z2022. @6 A4 s' ~* r; x1 a& ~. I
Certifificate Authority Cup International Mathematical Contest Modeling0 _$ h9 J6 z( O0 n8 t+ m* `
http://mcm.tzmcm.cn . W; N! ^. Z1 S/ [$ t7 M: D0 j4 iProblem B (MCM)* H) \& j9 o( Q+ u/ k
The Genetic Process of Sequences 3 {; P3 ?# [; r+ n9 N) ASequence homology is the biological homology between DNA, RNA, or protein & w( ~0 w% E/ w# c1 z1 \! k3 Qsequences, defifined in terms of shared ancestry in the evolutionary history of * B2 Y* J2 M. U1 V( |0 M Dlife[1]. Homology among DNA, RNA, or proteins is typically inferred from their P& {. k1 o( y* O9 }% g' ?nucleotide or amino acid sequence similarity. Signifificant similarity is strong - h% E( V/ l( ^" x! H Y$ I* {2 p# Nevidence that two sequences are related by evolutionary changes from a common 8 Y6 F# r% a( K! |) Wancestral sequence[2]. 7 ~6 e) t5 Y9 x& ~6 J7 F) e# r4 m# Y$ [Consider the genetic process of a RNA sequence, in which mutations in nu3 T* l2 q- W, u% o$ @6 [2 N8 j
cleotide bases occur by chance. For simplicity, we assume the sequence mutation - g0 k3 B/ |" s6 Y; e, D' \arise due to the presence of change (transition or transversion), insertion and * R9 o4 X2 \' K. `8 ^0 r( hdeletion of a single base. So we can measure the distance of two sequences by # G5 W: W8 ^4 H* A9 f2 kthe amount of mutation points. Multiple base sequences that are close together 1 E- r& J( L9 a4 _7 mcan form a family, and they are considered homologous. 4 n; G, P6 i$ E, xYour team are asked to develop a reasonable mathematical model to com8 g9 b! g& h) ^; F7 v1 @) a6 e2 Q
plete the following problems. & V- X6 H$ @# V- {, C8 W1. Please design an algorithm that quickly measures the distance between 3 u! E4 E7 b6 Y" _. u! y! K; y2 ^two suffiffifficiently long(> 103 bases) base sequences.; O/ s+ C, p2 `% k6 m0 ^! G
2. Please evaluate the complexity and accuracy of the algorithm reliably, and) u, f, u2 f6 q* n
design suitable examples to illustrate it.! `5 M4 D, c2 F4 g: ^* g9 \$ n
3. If multiple base sequences in a family have evolved from a common an7 c2 T5 a* @4 S' {) E/ V' L7 ]
cestral sequence, design an effiffifficient algorithm to determine the ancestral ! r4 c8 b+ a! ]& Nsequence, and map the genealogical tree. ; ^8 w! p6 f+ {) `References - k f9 Y7 ~3 _7 Y[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re+ W5 Z/ `+ c) s* W
view of Genetics. 39: 30938, 2005. - r4 [ e1 r( F- n, i# E' F[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,' B* e, [* l1 p2 Z2 J# R* ~" I
et al. “Homology” in proteins and nucleic acids: a terminology muddle and + x6 Y2 i. u8 ~7 H p- |/ @a way out of it. Cell. 50 (5): 667, 1987.! K" r7 z3 k, j
( `$ a& _. @. o) f! u* U
2022 h3 t4 }% h: T" ]( W6 Z
Certifificate Authority Cup International Mathematical Contest Modeling ' G& I, H2 C- U$ V6 Fhttp://mcm.tzmcm.cn " I7 U* h8 P5 vProblem C (ICM)& b2 [1 c0 [- P' W2 ~+ r
Classify Human Activities7 o, g5 Z/ ]- N0 ?
One important aspect of human behavior understanding is the recognition and ; @% }8 x( X: k" N1 f3 `monitoring of daily activities. A wearable activity recognition system can im # I) S: f6 A; X$ _7 D$ Dprove the quality of life in many critical areas, such as ambulatory monitor& J& m8 p, h, H% E# B. q) w
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ; j+ o' p- s2 p5 W: z
ity recognition systems are used in monitoring and observation of the elderly / ?4 g1 f4 `- hremotely by personal alarm systems[1], detection and classifification of falls[2],/ Q9 F7 y% L- [! @9 w# k- }
medical diagnosis and treatment[3], monitoring children remotely at home or in7 N1 K4 I+ n1 ~6 N
school, rehabilitation and physical therapy , biomechanics research, ergonomics,) q+ q2 t& A/ k- z, _7 j7 R# G
sports science, ballet and dance, animation, fifilm making, TV, live entertain6 W1 n$ j$ f/ f6 h+ e
ment, virtual reality, and computer games[4]. We try to use miniature inertial2 }4 y, o# J8 K- n7 t* Q. Z
sensors and magnetometers positioned on difffferent parts of the body to classify7 ?' ?9 D N! z' a8 x$ t
human activities, the following data were obtained. 3 ^0 {* K2 l' ?, E5 y8 j. q6 `Each of the 19 activities is performed by eight subjects (4 female, 4 male, / {- p5 b( [; ]& qbetween the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes / \2 c& {7 p+ F# ], l7 qfor each activity of each subject. The subjects are asked to perform the activ, }- ]; ?4 L: g, {/ C) N
ities in their own style and were not restricted on how the activities should be ( [ G7 v- L; L2 C' T2 \9 }4 Cperformed. For this reason, there are inter-subject variations in the speeds and( Q. j; S% Y( }1 X T# v8 Y
amplitudes of some activities.& e. J1 T" w; v6 r
Sensor units are calibrated to acquire data at 25 Hz sampling frequency.$ [7 F: j$ K" H _
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal1 s& m8 e% k& u$ C( H; E
segments are obtained for each activity.4 G7 x7 Z4 W( U; r9 o( [
The 19 activities are: 3 u1 D) N9 }5 L' m) W& X* C1. Sitting (A1); ) C, z* @4 _7 w) p2. Standing (A2); 8 x, t6 s4 R' _4 N6 o3. Lying on back (A3);; T7 a" F, X, e O
4. Lying on right side (A4);! l/ N3 J" D: D6 u3 a
5. Ascending stairs (A5);" F( K9 M- g* C4 e
16. Descending stairs (A6); . L; m g- ?. v, q- L& K7. Standing in an elevator still (A7);5 h0 o! `' W( c# o
8. Moving around in an elevator (A8);2 L& U6 M. E" ~. \
9. Walking in a parking lot (A9);5 W/ s6 S7 y, m. W
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg/ L5 @9 i! Q2 o1 I! D
inclined positions (A10); 5 v: \/ v* I8 ?" ]11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions 9 q* R1 z1 h- V! X(A11);& i6 o7 H N% a$ s* W. N
12. Running on a treadmill with a speed of 8 km/h (A12); $ t( k# h G+ }: q13. Exercising on a stepper (A13); 0 U+ z3 A$ Q) p# X' d9 |1 t14. Exercising on a cross trainer (A14);2 x! f5 a: Y7 S! w- E
15. Cycling on an exercise bike in horizontal position (A15); 0 y3 R* @/ A4 W! |$ X- o9 p U) E16. Cycling on an exercise bike in vertical position (A16); H9 m7 w0 i+ t1 n/ F17. Rowing (A17); # {) `) C# Z: H6 H6 @) @# x2 K18. Jumping (A18);3 N' h8 v1 o5 i: v' u
19. Playing basketball (A19). ! d) U( m; r. n7 JYour team are asked to develop a reasonable mathematical model to solve 4 `: I7 n9 K/ x+ G! @the following problems. $ g' ?7 V$ Q( r5 J6 g1. Please design a set of features and an effiffifficient algorithm in order to classify " l \% l; E9 c! Q1 _& ? Hthe 19 types of human actions from the data of these body-worn sensors.) m, |5 Z" n2 j- A+ d& g r5 h
2. Because of the high cost of the data, we need to make the model have$ u: ^, R5 w+ ]* E. G& l
a good generalization ability with a limited data set. We need to study ' d T. _+ X4 rand evaluate this problem specififically. Please design a feasible method to 7 C/ D! o* x4 q( r- ]evaluate the generalization ability of your model.) K8 y! f( y( x4 r' {5 {
3. Please study and overcome the overfifitting problem so that your classififi- % U3 e9 O6 l+ x E3 ocation algorithm can be widely used on the problem of people’s action, P: {5 m3 Q# n# i! R7 b: h7 \
classifification.; K! ]5 A) [ X
The complete data can be downloaded through the following link:$ X! O7 n7 i' z* a5 R C N
https://caiyun.139.com/m/i?0F5CJUOrpy8oq) Y& `- T9 {2 t% q7 f) _; n
2Appendix: File structure+ n c" ^; m7 ?- N2 K
• 19 activities (a) 6 s' z. `* k E* d2 e) O• 8 subjects (p): W! }# k( O- b4 s$ b' Y/ P4 E
• 60 segments (s)# [5 L' A& C8 y1 {, {3 {0 G
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left $ {3 b( x0 K! [# sleg (LL) & b. E" t* P0 M' N% J. {( D• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z9 w5 a: {8 ^! t/ c3 q
magnetometers)9 m# q% r2 q) P; U; \ k/ L
Folders a01, a02, ..., a19 contain data recorded from the 19 activities. # I5 [$ e8 [$ {, Q) A* G4 xFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the 6 P; p; U# w+ c* a$ R0 `# p8 subjects.. w* I0 r6 l) W% E
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each & m% ^# u0 v. r& B+ Z- Csegment.) \$ b1 T1 @5 `! c
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 / U0 k7 O% w! A m! RHz = 125 rows.( T2 _- ^; N6 G9 R0 e( w$ ?
Each column contains the 125 samples of data acquired from one of the( }" n! t" P+ g$ _/ q0 ]. {
sensors of one of the units over a period of 5 sec.) A5 i [9 |# k. |: b9 J
Each row contains data acquired from all of the 45 sensor axes at a particular $ T }3 b8 J4 ]& n+ p0 `$ isampling instant separated by commas. + P0 h3 @( J7 g8 e' m( \0 @/ p; cColumns 1-45 correspond to: $ i% \$ F4 m. g; }2 G( F, W8 ?1 @9 V• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,; H3 H. K& t( v. |. a! l
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,) ?. x+ H# {- ?4 R
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, / z/ j$ e7 E+ k• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,+ v7 d4 |0 n1 K$ e* e
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. & N+ z8 |9 |, VTherefore,6 O p) ^8 e; H- _4 y, A1 {
• columns 1-9 correspond to the sensors in unit 1 (T),: q* t$ x: c' u1 A
• columns 10-18 correspond to the sensors in unit 2 (RA),/ {0 _# w: O7 ^+ @
• columns 19-27 correspond to the sensors in unit 3 (LA),% X- D2 v @/ H0 T' i' b
• columns 28-36 correspond to the sensors in unit 4 (RL), - c2 A- W# _- ^+ x5 l' _# @• columns 37-45 correspond to the sensors in unit 5 (LL). " x$ }8 R& o4 j1 A0 f3References5 w6 v( v% k4 y( p9 L5 ?8 k, x0 ?) _9 w
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic) V7 H5 r. g) P; G+ e5 G6 H
daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.: W2 G6 z4 E" D5 T
42(5), 679-687, 2004) h! u1 X/ N2 y( F0 O$ t: _4 [
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of * K# a! M3 l$ i1 v* ?low-complexity fall detection algorithms for body attached accelerometers. 4 C- @( \1 n! H) Y' Z* y* Z+ `Gait Posture 28(2), 285-291, 2008 . R2 y8 J3 V0 k[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag 6 r) s; v/ J- [, |8 k8 fnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.# f. S0 A5 D' j E* R
B. 11(5), 553-562, 2007 {3 Q9 @; v! R3 Y9 {
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con $ m% o2 V* u* ^1 ztrol of a physically simulated character. ACM T. Graphic. 27(5), 2008 " Y! J- X3 k# u# W5 J , I: N/ L" H8 `; c: K2022 ( ^+ d# l4 h$ h9 W. rCertifificate Authority Cup International Mathematical Contest Modeling: ]& c1 R$ W7 q. i7 ` S, A& t) `
http://mcm.tzmcm.cn; K2 p! a8 V9 _
Problem D (ICM)& \9 _7 W! x/ t& j$ U% [
Whether Wildlife Trade Should Be Banned for a Long 4 I* v7 T1 o/ E/ L( g* D2 T7 @# tTime) Y0 O) x q9 r6 z0 g3 h, V( y/ ?0 u
Wild-animal markets are the suspected origin of the current outbreak and the ' [ [7 Q: l( m2002 SARS outbreak, And eating wild meat is thought to have been a source . A( K/ \- ~: `" \$ k: V( h) Zof the Ebola virus in Africa. Chinas top law-making body has permanently% h' @$ z* C5 _6 \
tightened rules on trading wildlife in the wake of the coronavirus outbreak, 1 J7 t c6 H" a' h# \which is thought to have originated in a wild-animal market in Wuhan. Some q/ a4 Z2 T, ^, M$ N
scientists speculate that the emergency measure will be lifted once the outbreak 8 I) m7 I! b/ ?! |( V7 s* xends. $ |! z. V0 [# \. n" iHow the trade in wildlife products should be regulated in the long term? ) _6 G; D/ @ ]1 Z) }Some researchers want a total ban on wildlife trade, without exceptions, whereas 5 `- ^5 @5 @/ l( i4 zothers say sustainable trade of some animals is possible and benefificial for peo 7 k' Z4 o$ H, aple who rely on it for their livelihoods. Banning wild meat consumption could1 Q! n* i0 ?. b: a v/ o8 k
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil( u' ?! ^; m% A3 J7 A9 L8 m' \
lion people out of a job, according to estimates from the non-profifit Society of 7 b) I- L) v5 n4 S, fEntrepreneurs and Ecology in Beijing.2 _8 i4 e( e8 A x6 Y& N' u
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology - ~0 X* U. ^1 v& }; uin China, chasing the origin of the deadly SARS virus, have fifinally found their! E* y9 Y3 P/ K$ r& F
smoking gun in 2017. In a remote cave in Yunnan province, virologists have 1 W# B6 j$ [- P1 \: [* G- T. qidentifified a single population of horseshoe bats that harbours virus strains with - y7 i$ b8 c( ^$ N0 H: Tall the genetic building blocks of the one that jumped to humans in 2002, killing- B; ?$ P4 L8 s/ w0 i( j* u! A, N
almost 800 people around the world. The killer strain could easily have arisen- {- g9 R4 h' c, G" I8 f
from such a bat population, the researchers report in PLoS Pathogens on 30! N+ m# n! Z- q- T8 O$ l( l
November, 2017. Another outstanding question is how a virus from bats in # ?. q( ^8 l/ M; y3 X# ]. WYunnan could travel to animals and humans around 1,000 kilometres away in; R- \ x; {) [
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife # R+ |8 v) _8 O) ltrade is the answer. Although wild animals are cooked at high temperature 8 g9 E. B) s( \$ I, |# Nwhen eating, some viruses are diffiffifficult to survive, humans may come into contact ) ]6 R+ F& S" [& R' F. Cwith animal secretions in the wildlife market. They warn that the ingredients / X5 o& ]5 u7 {4 i$ y2 L3 W' Uare in place for a similar disease to emerge again. - D5 u* D: T! I+ w$ p, m4 d; RWildlife trade has many negative effffects, with the most important ones being:2 \' k1 V( v* ]
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS4 D2 G, N/ u, K# U7 [- D) M) P
outbreak in 2002.Credit: Matthew Maran/NPL; a5 J, \/ e8 p
• Decline and extinction of populations . |5 h( A! O8 X: Q+ \• Introduction of invasive species, Q1 G+ K6 }3 U0 x, t3 u3 y5 w
• Spread of new diseases to humans4 M! N E4 q# G) N1 r8 b4 j3 I4 W
We use the CITES trade database as source for my data. This database 8 ^$ e3 g2 U/ |! {contains more than 20 million records of trade and is openly accessible. The ( J8 P; i: G- x1 A& U8 zappendix is the data on mammal trade from 1990 to 2021, and the complete . y( m. o( x0 ndatabase can also be obtained through the following link: b4 ~* m% x. r4 R6 t! Bhttps://caiyun.139.com/m/i?0F5CKACoDDpEJ 0 ]/ h% H2 g. {; X; K; bRequirements Your team are asked to build reasonable mathematical mod; t6 L" ~) C+ f( |7 m
els, analyze the data, and solve the following problems: ' G$ o8 i7 j: e! V t+ r2 ]" A/ q1. Which wildlife groups and species are traded the most (in terms of live ' I( U2 M P* g t6 Q! S% T- banimals taken from the wild)? & G/ p4 A9 \8 z& O* e, m/ }9 F' H4 J2. What are the main purposes for trade of these animals? : s0 l: f5 V' `3. How has the trade changed over the past two decades (2003-2022)? 0 `' L4 T9 c1 G* {( y0 K4. Whether the wildlife trade is related to the epidemic situation of major3 V$ r7 M5 x. h# q; W; J
infectious diseases? 2 i- K6 A: X8 W5 U' O/ S25. Do you agree with banning on wildlife trade for a long time? Whether it4 c0 L* {/ b" {- K6 |* D) T
will have a great impact on the economy and society, and why?1 `2 k0 E2 G8 U" }8 N2 L5 N# |: z
6. Write a letter to the relevant departments of the US government to explain) e, [) i( E' H v& }: k. b" a
your views and policy suggestions.- Q# l D |) t% r2 X( }7 n
1 U7 P' x5 x* g3 Z
7 m& `1 _# I# D0 r ) s/ v P# ?' [3 a 5 P# v6 M7 T' n3 `) l3 Z' w$ q - G. R5 y) B) j- i6 N* y4 p5 E' @2 n5 s. i* k