2022小美赛赛题的移动云盘下载地址 4 X; I! j. U+ q7 G! `. ^https://caiyun.139.com/m/i?0F5CJAMhGgSJx 7 v, j; G+ c: b4 K% Y ; Y& V* c8 T2 C* |+ O- {) Q, Y2022 0 @1 `5 {% d* D" q% F! D" t( MCertifificate Authority Cup International Mathematical Contest Modeling ( s. K6 U0 V0 G! C0 }http://mcm.tzmcm.cn" j8 J: U* [5 Z2 x. c2 D+ w8 t
Problem A (MCM) 5 ?* U1 a2 t, A( l; B3 X4 cHow Pterosaurs Fly 7 I5 e8 [& \6 W2 u: kPterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They6 S9 R f- r% G7 x- [) F
existed during most of the Mesozoic: from the Late Triassic to the end of 8 e) z8 i5 E# \9 Z( @the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved8 h5 z! @& S( j! P
powered flflight. Their wings were formed by a membrane of skin, muscle, and & `& Q/ ?, b% x; r o, `$ p! G- [other tissues stretching from the ankles to a dramatically lengthened fourth % p) x1 P" r1 W { mfifinger[1]. " b5 U# p/ F# BThere were two major types of pterosaurs. Basal pterosaurs were smaller. u* I+ s* t+ d) L& a7 v
animals with fully toothed jaws and long tails usually. Their wide wing mem : }/ l5 [' c$ p: Z& [) I7 }$ Abranes probably included and connected the hind legs. On the ground, they) H# [* }8 P$ ]2 M
would have had an awkward sprawling posture, but their joint anatomy and' q4 y6 p: ^2 f
strong claws would have made them effffective climbers, and they may have lived% L3 A& Z3 ~! D3 `! J9 @
in trees. Basal pterosaurs were insectivores or predators of small vertebrates.( H1 D8 [* J5 O" F
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. & {; F' V1 d! K* f- CPterodactyloids had narrower wings with free hind limbs, highly reduced tails, ; m9 T+ U/ p8 W1 Band long necks with large heads. On the ground, pterodactyloids walked well on* R0 y7 c6 X# @% c) u
all four limbs with an upright posture, standing plantigrade on the hind feet and 1 {+ z' m* V7 r5 ]folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil0 S; ~; w* p$ Q9 p8 R+ N1 E/ N* f
trackways show at least some species were able to run and wade or swim[2].+ [6 Z3 \' H5 M3 e/ s% W# r
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which 9 v. C" H( m- e* J6 w" Ncovered their bodies and parts of their wings[3]. In life, pterosaurs would have # a7 o9 m/ N% i: U+ [8 n& ?5 Fhad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug, [) [, G7 l- K2 B
gestions were that pterosaurs were largely cold-blooded gliding animals, de4 W b" m0 o+ f1 a4 L& B
riving warmth from the environment like modern lizards, rather than burning ; M0 }# l' x# Q: w) Mcalories. However, later studies have shown that they may be warm-blooded ' r; Y9 N7 T5 ^% M(endothermic), active animals. The respiratory system had effiffifficient unidirec& h) H3 Z3 \8 n" G. J
tional “flflow-through” breathing using air sacs, which hollowed out their bones+ V, X$ P; C/ ]$ c# t X9 ~/ c
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from 2 M- S7 i3 S+ m( zthe very small anurognathids to the largest known flflying creatures, including 1 r$ S. s4 c! w: M6 u- nQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least . r; h/ w1 G9 z: S1 @$ U! F. wnine metres. The combination of endothermy, a good oxygen supply and strong. J E9 h9 I- L0 e5 {& L# P, U" F) t
1muscles made pterosaurs powerful and capable flflyers. ; l! N* q/ u* N* M, vThe mechanics of pterosaur flflight are not completely understood or modeled 2 k* s- C b2 k9 q H+ a1 M7 ?9 m+ Nat this time. Katsufumi Sato did calculations using modern birds and concluded % H- U# Z J. o7 b! o* zthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture, : [1 T8 i5 q; B" _; vLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able & @$ f$ Y5 R; X e; \* N. _to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. ]9 y9 G5 r l) W/ r
However, both Sato and the authors of Posture, Locomotion, and Paleoecology( @! U+ @: P. \5 {8 ^1 G" S
of Pterosaurs based their research on the now-outdated theories of pterosaurs ; s! E) q# M) R+ K+ Y Gbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, }( t5 a, _2 W+ s$ `/ C
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that # v& K3 e4 ^: N1 C8 Yatmospheric difffferences between the present and the Mesozoic were not needed ~' w% t$ U8 Z% Efor the giant size of pterosaurs[8]. 6 X+ r, D$ F" _0 ?8 F' wAnother issue that has been diffiffifficult to understand is how they took offff.2 x j9 `0 |9 ]% {
If pterosaurs were cold-blooded animals, it was unclear how the larger ones6 B2 Q, p( v& z5 N+ `9 }6 l% f! k
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage 4 ]6 a; ?' D6 g# y2 U$ z* pa bird-like takeoffff strategy, using only the hind limbs to generate thrust for 2 h, S2 v: I1 }7 bgetting airborne. Later research shows them instead as being warm-blooded, G5 ]% U4 x- Y5 d2 l3 F
and having powerful flflight muscles, and using the flflight muscles for walking as' A0 A: J" i+ R- h( f6 N% N
quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of * z, i! W2 V) uJohns Hopkins University suggested that pterosaurs used a vaulting mechanism - d' z. F& _7 o- f9 \to obtain flflight[10]. The tremendous power of their winged forelimbs would ' ~* W0 B) h5 |1 oenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds' R. V8 Y" B2 a9 Y, o; E
of up to 120 km/h and travel thousands of kilometres[10]. ) o a- @, _0 J3 IYour team are asked to develop a reasonable mathematical model of the! I' [2 Y0 ?5 B7 H9 p' s4 ^2 }4 n( v! G
flflight process of at least one large pterosaur based on fossil measurements and # C" Q% K/ F/ j0 eto answer the following questions., ~8 d9 K2 [+ b, ?9 w
1. For your selected pterosaur species, estimate its average speed during nor7 d$ l8 P7 @$ X7 ?3 c
mal flflight.2 {+ J4 K1 |, b4 _8 t ]
2. For your selected pterosaur species, estimate its wing-flflap frequency during 2 U3 z) b- x% ~5 w& V4 B/ V5 P! Onormal flflight.7 ~ o; }) C& h9 @1 ?3 y- a& A
3. Study how large pterosaurs take offff; is it possible for them to take offff like- B& R! ~8 G2 B k" l- ?
birds on flflat ground or on water? Explain the reasons quantitatively.- S) D; B8 ], o# o
References % |; @( b5 e; X) d: z/ ?, l[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight% @/ ~$ P5 x4 |7 r5 R6 U
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111. & \( D @8 {& J- G# Z/ N0 ]) I8 b2[2] Mark Witton. Terrestrial Locomotion.1 \' m' z- |) f9 k- M6 z
https://pterosaur.net/terrestrial locomotion.php/ e& }2 F2 x6 N! T
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs$ E( g$ I& s" I' J, U( w
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324-* ?$ R# [3 v1 t. x. a! `
pterosaurs-had-feathers.html 0 C$ z( b7 X* C4 l) i[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a' E$ I/ [7 k" m0 `9 u1 [4 G
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)+ v5 L8 `6 A# W% B
from China. Proceedings of the National Academy of Sciences. 105 (6):2 p; u3 Q0 X4 g; R: b
1983-87. # U, f0 d0 p+ c/ t5 O( [[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust * ~! r% z& Y. ^/ |. ~! J5 a* ]skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):' f% R" p0 F6 ^
180-84.# n+ k8 Q% e6 i9 Y" |8 W# P2 J2 n
[6] Devin Powell. Were pterosaurs too big to flfly? 7 l: l3 q4 ^* N" Hhttps://www.newscientist.com/article/mg20026763-800-were-pterosaurs 8 _. \7 D. x: |5 Otoo-big-to-flfly/ ! d; m# A- b, h5 x- T4 P! l+ G[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology) m" \& O, k" r8 N5 j
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. ( E3 B+ U" B) E& I[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable7 f& `4 r# f% T7 Z
air sacs in their wings.8 J1 F( R: |# r0 {* ^% d' I& z6 ?' c
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur + k- Z& t* K: r3 I% x6 qbreathing-air-sacs! ?3 `5 x! z" f; G5 f* v: F* w
[9] Mark Witton. Why pterosaurs weren’t so scary after all.% t# p5 Q$ a4 `
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils- u: \9 B' R- y$ X+ A
research-mark-witton * |/ m0 @5 l) e7 @[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?2 c/ f. L- ]7 [& U# K
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs- Y9 [5 D( g& N% Y
vault-aloft-like-vampire-bats/* a* B8 p U- s. d5 W: e: P
3 S' J+ M4 I% {! O+ L
2022 ; L1 t3 u: d3 H" ^" oCertifificate Authority Cup International Mathematical Contest Modeling * I; K' o9 N Q' s. v: r* phttp://mcm.tzmcm.cn+ S+ U% A! W/ Y* m5 `/ R
Problem B (MCM), d- h) @6 ?8 x; G' n3 o/ x9 _
The Genetic Process of Sequences, W/ Y' u0 n7 e; X5 `( D) P
Sequence homology is the biological homology between DNA, RNA, or protein 7 w+ t; r, \( A7 Osequences, defifined in terms of shared ancestry in the evolutionary history of ' i- A& d8 i; m" klife[1]. Homology among DNA, RNA, or proteins is typically inferred from their, K6 E* p2 W4 v% _$ L1 D
nucleotide or amino acid sequence similarity. Signifificant similarity is strong 3 ?- M( S+ y- P- eevidence that two sequences are related by evolutionary changes from a common8 o+ t8 @5 V3 Q5 V: i9 v" ]' J4 f5 ?
ancestral sequence[2]. 5 [- M U ]8 Q. X- M C+ bConsider the genetic process of a RNA sequence, in which mutations in nu 7 a5 ~/ i* O7 F% ocleotide bases occur by chance. For simplicity, we assume the sequence mutation/ t+ m) w; G0 E1 P( A) O
arise due to the presence of change (transition or transversion), insertion and ) ]# I: u% ^9 Y: z' N7 sdeletion of a single base. So we can measure the distance of two sequences by1 `5 |: b/ o( W. S6 H. [
the amount of mutation points. Multiple base sequences that are close together $ L9 N8 G, ?/ b; ?& mcan form a family, and they are considered homologous. 9 i/ k; Z* b& H- H+ J" K& [Your team are asked to develop a reasonable mathematical model to com - `- U7 n- Y6 w- N0 Oplete the following problems. 1 K, i+ e }3 M1. Please design an algorithm that quickly measures the distance between, x* z* d1 d! {$ t* k. P. z
two suffiffifficiently long(> 103 bases) base sequences. / z( A0 B" K; c- k2. Please evaluate the complexity and accuracy of the algorithm reliably, and& t, @4 E6 C4 X! e7 }
design suitable examples to illustrate it. * f9 Z9 b/ ?% {% z3. If multiple base sequences in a family have evolved from a common an 9 T& [$ Q) ^8 o. J6 [$ Qcestral sequence, design an effiffifficient algorithm to determine the ancestral + a b3 n# t: E2 S# m1 \sequence, and map the genealogical tree." o2 a, Z% j/ @) W" w1 {+ Y9 Y
References! k; J0 K, i& e
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re# [5 U V- S4 b: @7 p* \
view of Genetics. 39: 30938, 2005. - s3 `5 ^ A. Q[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, 1 \5 H1 y, P- Iet al. “Homology” in proteins and nucleic acids: a terminology muddle and0 R" g8 a7 w1 | Q& @
a way out of it. Cell. 50 (5): 667, 1987. 2 e/ h: M3 k4 F1 t. P( `/ K9 F- G9 _7 P4 T: y- B7 R6 }! I! ^, U
2022! r! R% j4 o; U }$ G. \/ t
Certifificate Authority Cup International Mathematical Contest Modeling 4 `& f7 y) S2 T& w$ }http://mcm.tzmcm.cn 9 H' Z7 t* U; b: I/ HProblem C (ICM) - Z; q* X5 V2 H* iClassify Human Activities - K3 R4 N/ `4 \: L( HOne important aspect of human behavior understanding is the recognition and' n6 L' f% I- d% c4 R
monitoring of daily activities. A wearable activity recognition system can im! i1 \, m3 g' ]& S: @3 C
prove the quality of life in many critical areas, such as ambulatory monitor+ ^( r5 M/ y2 w. S8 [4 c
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ1 p% J& k: i9 r0 P1 ]
ity recognition systems are used in monitoring and observation of the elderly + q: A {7 I5 u* n3 L* ^remotely by personal alarm systems[1], detection and classifification of falls[2],# H5 H% y% P) Y" E4 W# o
medical diagnosis and treatment[3], monitoring children remotely at home or in ; {" Y1 ]& n0 p( S! Xschool, rehabilitation and physical therapy , biomechanics research, ergonomics,* K- u- S6 o' m* v; s/ C5 r
sports science, ballet and dance, animation, fifilm making, TV, live entertain- j5 d; l8 }6 ^
ment, virtual reality, and computer games[4]. We try to use miniature inertial" V/ s+ }4 W( a
sensors and magnetometers positioned on difffferent parts of the body to classify( B$ e, E! w/ l' R1 a
human activities, the following data were obtained.2 |5 f. W8 c' l6 w2 x/ y
Each of the 19 activities is performed by eight subjects (4 female, 4 male,$ W$ v" s, e6 F
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes+ L$ Z; ]5 g n7 E* S/ d5 y
for each activity of each subject. The subjects are asked to perform the activ% S$ B C+ X d* i& I7 T* U
ities in their own style and were not restricted on how the activities should be : |- Y- c" l/ S7 o- m& rperformed. For this reason, there are inter-subject variations in the speeds and& |2 @; ~$ z4 a
amplitudes of some activities. ) g3 M, l$ A0 @. F2 HSensor units are calibrated to acquire data at 25 Hz sampling frequency. ; E; d1 W& D' L- H1 NThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal2 E$ t7 A0 t/ l8 z# j. y" t. v( A
segments are obtained for each activity.. E! v- M# r- U( w$ `9 x9 e: _* o
The 19 activities are: 2 J# P0 J: z& s2 ^0 f$ z2 q1. Sitting (A1);- l8 }4 S! q0 g0 [! H* U0 I
2. Standing (A2);) X* N( i- [$ D; {' F, x2 J$ e
3. Lying on back (A3); # |( `3 f4 R6 v# N% Y4. Lying on right side (A4); : N. B& [8 o8 I+ j p, Q5. Ascending stairs (A5); 0 E3 e! [ D1 Y+ j16. Descending stairs (A6); 6 C& I5 _% `3 K( Q7. Standing in an elevator still (A7);6 ^' L5 `0 d$ a+ l( P! y# V
8. Moving around in an elevator (A8); % ?( y1 I/ i% i7 I) K# [5 Z9. Walking in a parking lot (A9);, o: f I: a$ ]
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg $ Y3 x9 i% i1 w7 p2 ~inclined positions (A10); 1 L8 Q. m3 P& ~11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions8 p- p) {1 s- _1 |
(A11); 0 W# x, q6 H6 y% _12. Running on a treadmill with a speed of 8 km/h (A12);2 o3 L+ Y) j q/ W, e& g/ T8 d
13. Exercising on a stepper (A13);' J# j! F0 b, j" J, Y
14. Exercising on a cross trainer (A14); 2 q& a0 Y( W" u15. Cycling on an exercise bike in horizontal position (A15); 6 ~; ]; M9 b% \- _7 c: T16. Cycling on an exercise bike in vertical position (A16);% |) X2 [# F8 ~; r1 q9 \- {! Y
17. Rowing (A17); d$ a. w0 O+ H+ h9 s3 y! h7 L
18. Jumping (A18); 3 q& |& `2 U/ N+ z* n19. Playing basketball (A19). 7 m5 e3 R2 @# E7 |( N4 vYour team are asked to develop a reasonable mathematical model to solve 0 o" @0 t) \- M$ @' D9 `/ lthe following problems. 3 Q: W+ u1 V( S( A1. Please design a set of features and an effiffifficient algorithm in order to classify ! o' P1 g, D# Z( u: cthe 19 types of human actions from the data of these body-worn sensors.* J3 X* \* _+ X0 z) T) p' p5 N
2. Because of the high cost of the data, we need to make the model have7 v7 L6 U/ x# I4 N6 c; q$ D( L. V. E
a good generalization ability with a limited data set. We need to study5 ?7 F# n: \. F! y- Y% \5 V& M" [
and evaluate this problem specififically. Please design a feasible method to7 b$ Z+ G. g, [: m
evaluate the generalization ability of your model. - v; G/ u8 T) V( U3. Please study and overcome the overfifitting problem so that your classififi- % [# I, n. ^9 {9 r$ Z3 Kcation algorithm can be widely used on the problem of people’s action $ U! A/ p/ B N6 R. lclassifification.+ X0 m6 _3 U" q5 o/ S8 ^
The complete data can be downloaded through the following link:4 Z- y0 @ s+ L \1 d
https://caiyun.139.com/m/i?0F5CJUOrpy8oq! m9 e! ^! a- G- H, g/ S
2Appendix: File structure/ y. m0 ]& Q6 S& P5 I- N3 O7 j1 [0 e
• 19 activities (a)4 n9 {) p* R# P2 y$ r" u# i
• 8 subjects (p) . O5 o& x+ m7 [/ o* `) v! b6 _• 60 segments (s)& I3 L: i' `1 h( D
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left# ^: o/ d1 }3 F/ e# J* {; ^2 i
leg (LL)" ^4 E. Z t$ Y& Y/ C3 ` a
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z( e$ @# U$ |0 ?: T f: D+ p
magnetometers) * T* h O4 t3 z, ^1 _/ PFolders a01, a02, ..., a19 contain data recorded from the 19 activities. ( e r0 P; K" v; SFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the 9 G" M) o/ o% Z7 k% T7 o' i0 S8 subjects.* q1 w M7 {/ M& z
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each X1 a9 \6 d9 a& t7 rsegment. * t. n" h4 W& Z, ~5 B2 k' aIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 5 b: r' ^; ]- K2 B& k6 D8 M3 v6 FHz = 125 rows.% l; Z6 o3 v2 r: m0 v$ z8 \: F* E
Each column contains the 125 samples of data acquired from one of the . J+ l8 \- q8 v7 Bsensors of one of the units over a period of 5 sec.5 e4 P B$ G' }: E& z6 k, p
Each row contains data acquired from all of the 45 sensor axes at a particular ' Z! D" I6 C' D: Z: V: o% Lsampling instant separated by commas.; A3 H" c6 R* J/ b0 y% Y
Columns 1-45 correspond to:$ g0 d' W) R1 s! u0 [# |$ Z
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, ! P+ \0 G2 y* f• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,' h" O0 m- U" g
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, # ?' {) W1 O, A' n+ \7 x• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, ( N+ ?- U$ _7 O! V. G• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.: j6 W$ _# b/ `
Therefore, * p! ` x$ ^. H! b1 R) Z0 c! p• columns 1-9 correspond to the sensors in unit 1 (T), 3 Y8 M$ C+ u' |• columns 10-18 correspond to the sensors in unit 2 (RA),8 R$ n% G2 R8 t$ |
• columns 19-27 correspond to the sensors in unit 3 (LA), : c. F! w1 L$ Q2 z3 w I• columns 28-36 correspond to the sensors in unit 4 (RL),9 j' ^5 U5 ?8 I' f
• columns 37-45 correspond to the sensors in unit 5 (LL).$ |$ {2 P) \) _: R+ ^; T
3References' ^/ V+ N$ W& |* A7 `* o: F
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic . C, M0 A" ]3 R+ Z7 o, ]daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.; w# m) T1 m: ?9 U1 k/ v
42(5), 679-687, 2004" O! }& X7 _1 i3 G9 u/ Y' [/ S3 R( p
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of 7 `" n$ N/ d- x% _# O* Alow-complexity fall detection algorithms for body attached accelerometers.5 X; F" Z$ B9 \# g: H: X& X
Gait Posture 28(2), 285-291, 2008+ b: N9 p# X6 l/ d* P$ B( g
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag " l. g% `' r; d7 {' H+ Bnosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. 9 W" _, N9 y6 CB. 11(5), 553-562, 2007 $ c3 \: [; d* g3 q* E/ |[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con8 V4 y( K, t* V" `0 ], _4 H$ b' z% h
trol of a physically simulated character. ACM T. Graphic. 27(5), 2008 2 p* n0 v& D6 \8 V) ]! d" x2 H. W9 w9 J0 M7 ?5 i
2022 / {3 Z b( d1 ?0 `Certifificate Authority Cup International Mathematical Contest Modeling/ F: ]- I) V6 `
http://mcm.tzmcm.cn6 L9 ~1 K' v" [& w
Problem D (ICM) 5 L) D: C$ L7 gWhether Wildlife Trade Should Be Banned for a Long7 q4 d* g& K5 c( w I: ^1 D
Time1 [- Y0 b0 x5 ~; [6 }" [& z# t* Q
Wild-animal markets are the suspected origin of the current outbreak and the + h5 I/ U4 D3 _/ o/ [7 J' Q6 ~& \2002 SARS outbreak, And eating wild meat is thought to have been a source# [: x" p) O: k+ ]2 Q% s1 V5 ]$ |' ?
of the Ebola virus in Africa. Chinas top law-making body has permanently ! E% _: G# y7 F, _tightened rules on trading wildlife in the wake of the coronavirus outbreak,- e# j$ L% P4 M, [2 G$ N) G K. J
which is thought to have originated in a wild-animal market in Wuhan. Some* ~" v3 }7 ]4 k) S7 H' S
scientists speculate that the emergency measure will be lifted once the outbreak$ L+ o3 z) l( X8 N
ends.# g4 {5 D! n& {. v5 b& [6 x8 K
How the trade in wildlife products should be regulated in the long term? $ Q+ A! l6 z+ y. Q& H7 |7 t* }Some researchers want a total ban on wildlife trade, without exceptions, whereas " U" t4 d6 y: X' R$ ^' Dothers say sustainable trade of some animals is possible and benefificial for peo l1 P$ y7 p2 [2 D' T4 [& W& c
ple who rely on it for their livelihoods. Banning wild meat consumption could ) n' l1 B: J" f# Z* Z4 Ncost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil" }+ M8 f: b" K) O7 N! r7 X
lion people out of a job, according to estimates from the non-profifit Society of# i/ i. C7 O0 Z. K( l: L# H
Entrepreneurs and Ecology in Beijing. 1 T* p. t; H$ h; zA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology % ~2 R G8 f1 t; v& rin China, chasing the origin of the deadly SARS virus, have fifinally found their 1 P+ Y5 V; O( e5 h1 ?/ M, bsmoking gun in 2017. In a remote cave in Yunnan province, virologists have * V. T: S" ~1 L, N _6 _ |identifified a single population of horseshoe bats that harbours virus strains with , K d$ s0 k9 u$ h6 A5 M2 vall the genetic building blocks of the one that jumped to humans in 2002, killing' C0 X2 j1 |$ b
almost 800 people around the world. The killer strain could easily have arisen : E9 c2 ~% E% F: k4 B( `3 I$ u1 h7 K% ufrom such a bat population, the researchers report in PLoS Pathogens on 30 " o! n+ |1 t) E, j0 e2 I9 Z7 _/ DNovember, 2017. Another outstanding question is how a virus from bats in " E! g4 P% X9 n' }* ~Yunnan could travel to animals and humans around 1,000 kilometres away in% w# P1 s9 d) \9 C) ?
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife . S- b. Y, W' Q% l1 E! Y) \trade is the answer. Although wild animals are cooked at high temperature6 U( N3 U, y0 q H) V/ ^' ^ o
when eating, some viruses are diffiffifficult to survive, humans may come into contact 8 B+ ^3 W5 D0 |with animal secretions in the wildlife market. They warn that the ingredients4 i$ q2 n3 i2 c7 e9 G
are in place for a similar disease to emerge again." k0 y# P4 v' K' P3 O3 C5 p& ^6 v9 n
Wildlife trade has many negative effffects, with the most important ones being:( ]. L0 m0 S" e; v
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS" J. s: Q5 e/ b0 J% B
outbreak in 2002.Credit: Matthew Maran/NPL2 L1 b6 u5 U) k, ^2 g
• Decline and extinction of populations: j1 C- p/ L2 v. [* W
• Introduction of invasive species ; t m0 {8 V0 Z9 X$ e• Spread of new diseases to humans# D3 t1 F1 d$ P* y2 g% Q
We use the CITES trade database as source for my data. This database: \% ^. r! X8 N; j$ T
contains more than 20 million records of trade and is openly accessible. The e* P' `, o1 yappendix is the data on mammal trade from 1990 to 2021, and the complete - I) U& p! J7 X& T8 [$ kdatabase can also be obtained through the following link: & r% ^ b) w# r- X$ Fhttps://caiyun.139.com/m/i?0F5CKACoDDpEJ ' w; |0 W6 r/ Y CRequirements Your team are asked to build reasonable mathematical mod ; ?9 B& z; u$ |, y. ^: Fels, analyze the data, and solve the following problems:$ ~* l# U8 g0 f- ^! @
1. Which wildlife groups and species are traded the most (in terms of live8 c! H2 S1 g o7 N( O" t
animals taken from the wild)? % x3 e3 P' ?: I! I2. What are the main purposes for trade of these animals?4 S0 S+ Z1 U- O7 N) P
3. How has the trade changed over the past two decades (2003-2022)? 0 m- R+ L" T) N' i9 E8 @: ]4. Whether the wildlife trade is related to the epidemic situation of major: l6 N w* q4 n+ H4 V& X
infectious diseases? 8 ]; n! l9 ]7 \: {# d8 t25. Do you agree with banning on wildlife trade for a long time? Whether it% q9 B% d) ?1 j) r6 [% N
will have a great impact on the economy and society, and why? ; E' R* Z. x/ x$ g5 H9 A2 K5 z6. Write a letter to the relevant departments of the US government to explain 1 R( a, l3 w' ^$ zyour views and policy suggestions.- A& U6 T8 t$ R2 X6 i& W6 I
: s6 ?# F4 }; y& s/ O9 c% _* a $ J! C2 @9 t) M- R7 |+ ~ 1 \: c1 J7 D2 O C' M" V4 a1 c, N3 k# R c6 O
9 Z4 V, s4 X3 c) I, o% A % _! o+ n& | J5 f, s- P$ P $ g3 F) b1 t; ]) r' F! ?( f