2022小美赛赛题的移动云盘下载地址 4 t, V. o$ ]# x) g5 Khttps://caiyun.139.com/m/i?0F5CJAMhGgSJx , G8 v/ ?5 k. L* }# F+ i & x3 H0 W- `/ S0 x+ ?. F" n2022 d4 [! W9 Q: Z2 `" \- m
Certifificate Authority Cup International Mathematical Contest Modeling2 b: U2 n% s' C, B/ f. `
http://mcm.tzmcm.cn0 j' k* l" r' ^+ o/ k9 A# S
Problem A (MCM)- x7 v ^5 J7 @7 ^
How Pterosaurs Fly0 a, e/ n' o+ N) J' b+ d
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They6 e* i4 s6 I2 r6 ]- N4 p# S' H% K$ r- D
existed during most of the Mesozoic: from the Late Triassic to the end of 3 O. Z+ @# _0 U8 S) K/ h7 Wthe Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved4 [' @! ^3 H! a, T) i3 g3 N
powered flflight. Their wings were formed by a membrane of skin, muscle, and# y6 t$ K) e4 W# N: @
other tissues stretching from the ankles to a dramatically lengthened fourth 6 {1 n4 c }0 W9 G6 Y. h- m$ Ofifinger[1].- d- B( P+ C9 r) x
There were two major types of pterosaurs. Basal pterosaurs were smaller* W6 W/ ]' C) L; W" q
animals with fully toothed jaws and long tails usually. Their wide wing mem % S( A) t5 {0 H% P2 o) {branes probably included and connected the hind legs. On the ground, they" q9 y; o2 w' @6 [- ^
would have had an awkward sprawling posture, but their joint anatomy and5 l/ H3 z3 C1 l7 ?8 V
strong claws would have made them effffective climbers, and they may have lived , s! w2 Z0 _& m# Qin trees. Basal pterosaurs were insectivores or predators of small vertebrates., W- B( ^" J" e8 Y6 i
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles. 9 E) q6 _! {; f" n) MPterodactyloids had narrower wings with free hind limbs, highly reduced tails,. E- [" j0 b! V5 Z% T1 m! {+ ~- }) w
and long necks with large heads. On the ground, pterodactyloids walked well on . x# F3 Y4 Z; ~8 e3 tall four limbs with an upright posture, standing plantigrade on the hind feet and 2 ^; ]0 \* H* j9 T7 u6 pfolding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil; @6 I& z9 W+ J i9 q5 Z; x
trackways show at least some species were able to run and wade or swim[2]. : ?1 s; y$ ^, v( fPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which 0 v0 h1 G8 | s. U! m# Qcovered their bodies and parts of their wings[3]. In life, pterosaurs would have8 x9 ?+ ], f G; z% p
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug 5 X0 V- o- E3 ]0 bgestions were that pterosaurs were largely cold-blooded gliding animals, de 8 s+ W o1 O% N" c9 ?riving warmth from the environment like modern lizards, rather than burning 4 p+ k6 u+ |& y! b$ xcalories. However, later studies have shown that they may be warm-blooded & p% n8 O: C+ W6 ~(endothermic), active animals. The respiratory system had effiffifficient unidirec 3 D& K" e2 T* ~ z* htional “flflow-through” breathing using air sacs, which hollowed out their bones! \& [+ n% I K4 {. A8 G+ Q6 L' v
to an extreme extent. Pterosaurs spanned a wide range of adult sizes, from. u3 j4 Q2 [" D; W
the very small anurognathids to the largest known flflying creatures, including o8 |( {; Q3 r2 f8 bQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 1 f5 X, @1 m! W+ A" w) a/ @nine metres. The combination of endothermy, a good oxygen supply and strong, v: u' h1 S5 n. l" l
1muscles made pterosaurs powerful and capable flflyers.0 a8 {: @0 D3 N
The mechanics of pterosaur flflight are not completely understood or modeled) c$ d+ E9 U9 D+ S, C: u4 [, i$ Y0 p
at this time. Katsufumi Sato did calculations using modern birds and concluded - \# r/ C! Z8 c' i, {that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,1 F1 @9 j4 D4 D; ^; k
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able & L- ~/ C P- Y3 ^to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].% F/ a9 V' ?; y9 r, C
However, both Sato and the authors of Posture, Locomotion, and Paleoecology2 W4 G4 ]# w; G9 [0 Y
of Pterosaurs based their research on the now-outdated theories of pterosaurs & i% E) _3 o5 e# kbeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, # w3 r# K6 _6 ^such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that 2 z( l# ^0 {9 w9 }- w7 V( Qatmospheric difffferences between the present and the Mesozoic were not needed7 @0 t+ d9 B1 ]( v
for the giant size of pterosaurs[8].8 e7 c% v, B1 d, m1 C: [- T
Another issue that has been diffiffifficult to understand is how they took offff.3 \" M% m9 G4 c& x
If pterosaurs were cold-blooded animals, it was unclear how the larger ones) d* V; K4 l( Q9 Q1 X; Z- `: D
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage ) l6 |/ @ J2 ?a bird-like takeoffff strategy, using only the hind limbs to generate thrust for - v5 t3 S5 d' \/ x" |$ ]getting airborne. Later research shows them instead as being warm-blooded ) N k0 P+ \0 E: f5 @# Rand having powerful flflight muscles, and using the flflight muscles for walking as' q ]: A' F' f5 s: E$ ^
quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of ! \1 X% o6 B6 i- @0 m zJohns Hopkins University suggested that pterosaurs used a vaulting mechanism + ]4 u' m' @/ u! V Nto obtain flflight[10]. The tremendous power of their winged forelimbs would : d7 i% {4 Z& `; d& N2 Lenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds & C& D* H4 L) q6 Wof up to 120 km/h and travel thousands of kilometres[10]., X% O$ J4 O9 G/ N( M0 s: o
Your team are asked to develop a reasonable mathematical model of the ?* ^5 z3 k/ Y% ] A
flflight process of at least one large pterosaur based on fossil measurements and) h* Z/ M+ A1 m6 W. h
to answer the following questions. ! s9 i, v9 D! O- T2 c1. For your selected pterosaur species, estimate its average speed during nor/ U! i7 S3 w! m% J3 H
mal flflight.4 q: y' m* A4 Y+ |6 E
2. For your selected pterosaur species, estimate its wing-flflap frequency during " C3 g2 B' w# y0 W" @- Nnormal flflight. ! G: [. q1 w, l5 \7 D. m, i3. Study how large pterosaurs take offff; is it possible for them to take offff like % V5 K' H/ O) }1 D! X& `birds on flflat ground or on water? Explain the reasons quantitatively.: o& Z+ \- F i5 y0 w
References4 J) r6 l1 Q! T! i
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight7 G/ d8 m5 m1 e) M2 G) r& d9 n
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111. ) H/ [8 ^; n- q2[2] Mark Witton. Terrestrial Locomotion.6 }2 l# m! Z+ e6 ]4 F. Y
https://pterosaur.net/terrestrial locomotion.php . e4 n/ v3 N1 P0 b[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs 5 W& z: |, Z, RWere Covered in Fluffffy Feathers. https://www.livescience.com/64324-3 U7 B" R( e/ R
pterosaurs-had-feathers.html d: d( X. {# T e$ O. P( X[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a 8 R7 ~( g' @! F) O7 a7 Urare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) + i' Z) l- H+ t* S5 T- lfrom China. Proceedings of the National Academy of Sciences. 105 (6):% r+ |6 N5 E4 P
1983-87. 8 z4 X* O; I% ?3 n: @: q[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust) F/ E8 a9 R! Q5 h
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):" ~0 r/ H1 q) B% J. Q5 Q6 l
180-84.* x2 d! Z' ^$ b5 V2 o2 D5 {
[6] Devin Powell. Were pterosaurs too big to flfly? 4 E) V1 `: e" ]! M5 W) Qhttps://www.newscientist.com/article/mg20026763-800-were-pterosaurs 5 u+ C6 o, k Z- U, T& x5 f3 ?too-big-to-flfly/ ' Y0 w/ \, |1 @: u[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology7 {2 h/ c9 T: K8 f; \6 P) E/ S
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60. 0 Q0 f8 N5 I9 y J, r[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable4 _) }; o3 |9 S
air sacs in their wings.# }* q: M5 X( R1 j2 ^/ f' C
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur3 |, `: F& G9 R {
breathing-air-sacs: ^) p: D# r. g. m/ [7 `
[9] Mark Witton. Why pterosaurs weren’t so scary after all. h b4 f* u" v$ E/ G# i' X( O% I
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils ) S' _1 ]' v; a U* ~research-mark-witton : x: q+ E( E |3 E4 ?[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? , p! L3 {! I1 W# D) zhttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs7 z6 b! @4 r S% C! f/ e" s* ^
vault-aloft-like-vampire-bats/! J) G: f- `+ ~4 b$ d) D, m
+ m8 f6 U' H' M
2022 # b6 \' {, L1 i6 eCertifificate Authority Cup International Mathematical Contest Modeling . F. U6 {3 V* m8 P0 G$ Y- ehttp://mcm.tzmcm.cn" L. H8 N+ G' w0 y1 [+ I
Problem B (MCM) , r8 Y7 c4 P- |: Y" a3 SThe Genetic Process of Sequences0 B# A8 \0 a! v4 a
Sequence homology is the biological homology between DNA, RNA, or protein * g8 P3 Y; T/ p) I$ msequences, defifined in terms of shared ancestry in the evolutionary history of2 \9 ?) W. R1 ^( L& m. Z# m7 |
life[1]. Homology among DNA, RNA, or proteins is typically inferred from their/ ^/ m, F6 K0 J5 Q/ b. [+ ]1 r1 c
nucleotide or amino acid sequence similarity. Signifificant similarity is strong! Z4 `# {, z" R5 Z- f. n
evidence that two sequences are related by evolutionary changes from a common6 g' R( r N4 d3 M" w
ancestral sequence[2].% f& i; ?4 s2 m
Consider the genetic process of a RNA sequence, in which mutations in nu3 @$ D+ Z7 c% P7 u+ q' w
cleotide bases occur by chance. For simplicity, we assume the sequence mutation% n% d( d! C, f5 W6 K: [6 D; E
arise due to the presence of change (transition or transversion), insertion and / K% y& U& x% |" m- Sdeletion of a single base. So we can measure the distance of two sequences by7 \' F# x8 \. M% ~: L1 \9 S
the amount of mutation points. Multiple base sequences that are close together 9 |) `8 D% w/ K& ^can form a family, and they are considered homologous. $ d) H. b9 e8 U$ C& Q' P# KYour team are asked to develop a reasonable mathematical model to com / X; k8 K- s! v; W6 X! P4 Eplete the following problems. 0 f8 h) M8 t8 g' x1. Please design an algorithm that quickly measures the distance between 7 O# l) B+ M3 n4 T) c: G. N( N' itwo suffiffifficiently long(> 103 bases) base sequences. * F, O# l- W/ L$ h' m& d8 U2. Please evaluate the complexity and accuracy of the algorithm reliably, and& g1 S8 I7 {. k8 q
design suitable examples to illustrate it. 9 f$ e2 m, n( {$ ?- P3. If multiple base sequences in a family have evolved from a common an ( j. R4 o) l7 H+ q" Z4 q( acestral sequence, design an effiffifficient algorithm to determine the ancestral 2 z' S# p( W1 V0 ]1 B. dsequence, and map the genealogical tree. 7 m* W% o6 U7 {/ K' Y1 h' nReferences & F; `: J' I3 D n[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re4 [: m: K% t0 b! C0 t7 g0 P/ K
view of Genetics. 39: 30938, 2005.2 _9 v6 _4 b8 v! O
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE, " P. y: y8 r" U9 Z/ n1 j% }; Qet al. “Homology” in proteins and nucleic acids: a terminology muddle and ) [4 m. i0 c* Ma way out of it. Cell. 50 (5): 667, 1987. 1 y8 ^: E1 m* m0 @% _' o6 A% `$ C
20220 g. ~% s( Z9 |- S1 i4 A
Certifificate Authority Cup International Mathematical Contest Modeling/ x* g6 S) v! X8 u, }
http://mcm.tzmcm.cn% n* c) n" I" p& Z; K
Problem C (ICM) 6 y! h) G4 H+ u) Z' X% R' T+ vClassify Human Activities0 H" l* d8 q9 Z2 B: J N
One important aspect of human behavior understanding is the recognition and7 k6 D) \1 Y M, a. F' z6 d
monitoring of daily activities. A wearable activity recognition system can im 3 p2 L; A; C+ K* T7 s6 \+ Sprove the quality of life in many critical areas, such as ambulatory monitor 5 l: m7 r. }: H4 Ying, home-based rehabilitation, and fall detection. Inertial sensor based activ - M. |; X; ~0 \1 [7 M0 ~1 Z' qity recognition systems are used in monitoring and observation of the elderly 1 H1 r; u( _& K' tremotely by personal alarm systems[1], detection and classifification of falls[2],2 r' s, p7 d" l* \+ w5 d
medical diagnosis and treatment[3], monitoring children remotely at home or in ' l" a( n- C. U4 ?- X' Y/ A+ n" Aschool, rehabilitation and physical therapy , biomechanics research, ergonomics, " g2 e1 g% I1 l7 _% m% k8 [8 Psports science, ballet and dance, animation, fifilm making, TV, live entertain' F3 u6 M8 {" {: @" S
ment, virtual reality, and computer games[4]. We try to use miniature inertial. \! [) d/ O; f9 R
sensors and magnetometers positioned on difffferent parts of the body to classify3 A% z. P. {- ^) W" j) ?
human activities, the following data were obtained. q0 @- ?2 u: w+ R; `! ]4 bEach of the 19 activities is performed by eight subjects (4 female, 4 male,# z: z G$ R# V: C% K
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes $ q1 h' K) F0 o* C4 T+ n' i. h% ?for each activity of each subject. The subjects are asked to perform the activ2 g9 _7 |2 L4 t! |- c
ities in their own style and were not restricted on how the activities should be 4 _9 w2 ~* B5 f: A5 x/ z; _2 xperformed. For this reason, there are inter-subject variations in the speeds and) H8 H1 @6 Y/ _. g
amplitudes of some activities.! R' f$ K" a; F/ U
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. 6 o5 o& f6 N) L, H' J+ @5 ~The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal $ M" w0 ~9 D: esegments are obtained for each activity. : ]" ]5 P- u, r, T c6 u" H" FThe 19 activities are: & m6 K+ D0 S: | t1. Sitting (A1); - ]2 i# h% D8 D8 `* l' w2. Standing (A2);% T( I. X2 U' r' e/ M
3. Lying on back (A3); 5 b) V7 {& t% O) H: R$ ?4. Lying on right side (A4); $ P" k" |! R7 w9 m* @2 L0 f5. Ascending stairs (A5); . h" D* j3 ]+ }$ h0 T# A' u% `16. Descending stairs (A6);) w, f( B8 m& n+ F+ b( R8 H
7. Standing in an elevator still (A7);! H9 y. I! R- d" D: \7 ]) n
8. Moving around in an elevator (A8);) Y# e: G& _- A1 X! x
9. Walking in a parking lot (A9); 2 ?7 T! d$ ]# Y( I% j. A% s5 a10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg' a" O/ f' w+ |: t: v- \4 `
inclined positions (A10); V+ |2 v! x! n2 `
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions3 D' ~; c, a, j, V
(A11);$ ~' }# @6 I4 C6 p* u' G6 ~
12. Running on a treadmill with a speed of 8 km/h (A12);# l) G* i: B# N( w, H* R
13. Exercising on a stepper (A13);8 w0 l/ |- [ V+ E: B
14. Exercising on a cross trainer (A14); 2 u- P- I. Q" E4 e* ^15. Cycling on an exercise bike in horizontal position (A15);+ A9 z/ L3 b) g5 h G/ @) o$ |
16. Cycling on an exercise bike in vertical position (A16);- j/ G+ ~# `) n Z& v
17. Rowing (A17);$ Q: z( K' r' Q
18. Jumping (A18); 8 A9 W, H- h/ [* @. U7 j19. Playing basketball (A19).' J% f4 Y( z0 C- r$ F l% Y
Your team are asked to develop a reasonable mathematical model to solve- B ~% C8 {$ U+ i8 ~8 h
the following problems.7 r/ M! o0 w. b4 ^0 H3 G
1. Please design a set of features and an effiffifficient algorithm in order to classify5 T1 A( d3 P6 \: R( U
the 19 types of human actions from the data of these body-worn sensors. 7 i: U6 _/ N7 o+ c( D0 ~ W) e$ [5 W2. Because of the high cost of the data, we need to make the model have7 m6 Y% F* E q0 y5 H" e5 U
a good generalization ability with a limited data set. We need to study4 o1 ]8 q8 X. K6 U
and evaluate this problem specififically. Please design a feasible method to 2 ^+ ~+ s5 [8 P2 Revaluate the generalization ability of your model.+ u: T/ u I& {9 [! s$ _. c E
3. Please study and overcome the overfifitting problem so that your classififi-5 T- I6 b7 _+ p z
cation algorithm can be widely used on the problem of people’s action8 g3 `4 L; ^7 U" c4 x
classifification. " i* j* x# S- ]0 F/ D2 q) bThe complete data can be downloaded through the following link:9 k+ z7 V7 `6 S( _/ r# U
https://caiyun.139.com/m/i?0F5CJUOrpy8oq4 C8 O) U& C2 l; {' m# ^( I% \% e `
2Appendix: File structure 9 G3 B2 ]; X9 t9 ^) g• 19 activities (a)6 j$ l$ A: _ x, d
• 8 subjects (p)0 w( G. G! z. b; Y# M) j7 Q H
• 60 segments (s) 0 A0 n. G: i$ \$ C' @• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left - I* P3 a' F# H# \! }leg (LL) 7 r! n4 C% W l# I• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z , a! ]! \ M# e4 Q+ w; hmagnetometers)" f$ O- T. D7 L6 j- \6 Q
Folders a01, a02, ..., a19 contain data recorded from the 19 activities.9 ` A7 f( t$ k8 B# X2 A
For each activity, the subfolders p1, p2, ..., p8 contain data from each of the5 I H9 F, z1 `- g1 K. Q
8 subjects. 2 B S. e9 S: N7 ^( p* l9 oIn each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each " o0 g& O' T! C6 K: o8 T: Rsegment. * @( }: t) D) j) k. N& k$ I* S- LIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 d% A& X/ e& p: VHz = 125 rows.# w$ ^2 i4 S( f( F2 A& ]- \
Each column contains the 125 samples of data acquired from one of the, e" C1 K1 W& f! ?
sensors of one of the units over a period of 5 sec. ' A; V6 I/ e3 a$ w! | C( bEach row contains data acquired from all of the 45 sensor axes at a particular & K; w! b# _4 w+ Tsampling instant separated by commas. 8 n- y, t, ^' o' R& H& ]Columns 1-45 correspond to:8 z8 [9 @4 a0 e9 Z5 u1 b( I$ t
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,8 P; n& z. X+ x" s9 |9 \ I
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag,2 t# `* t/ O2 l0 B$ g1 y2 h
• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, - M& R6 `1 b$ U' h! z6 B! @• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,, ^* U/ L- z/ Y
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.9 B! @* P3 K0 ^5 b4 A- a9 `& @# V% x5 @
Therefore,+ O4 h2 a. w* a5 }" v! M
• columns 1-9 correspond to the sensors in unit 1 (T), 5 @0 P& y7 Z/ G/ Y, \* R• columns 10-18 correspond to the sensors in unit 2 (RA),$ x4 H+ l# e: K8 y
• columns 19-27 correspond to the sensors in unit 3 (LA),4 ]0 H( Q2 \2 A9 T9 h' v1 R1 s
• columns 28-36 correspond to the sensors in unit 4 (RL), 2 b5 W2 f3 _2 y0 L q( z• columns 37-45 correspond to the sensors in unit 5 (LL). / r3 `* L5 \% {3References" \# H9 W0 L; x$ V9 e* Y- R
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic X0 |- O' g$ C% p' M( J" T; l7 Udaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput.2 a* p! s' E) ^5 b3 A! ]4 X
42(5), 679-687, 2004( f- ~$ |# w" n- ]2 D
[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of( k2 F% c0 N3 i, z: f; n
low-complexity fall detection algorithms for body attached accelerometers. , v, B% i1 o1 Q3 j8 J1 CGait Posture 28(2), 285-291, 2008 ( t, _* I( ~" v' u7 F5 `! Q9 i" U$ j& t[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag: }; |8 V5 T; x" N- q/ U
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. ) V: C" u) l1 vB. 11(5), 553-562, 20076 g. j* u: F2 C1 J6 i- E' V
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con 8 X7 @; B6 h: R# k: W/ U8 a1 `! {8 vtrol of a physically simulated character. ACM T. Graphic. 27(5), 2008 8 W5 b# D7 n. e+ x) l( N4 t x2 j0 S2 U6 }( W5 H( ^2 \5 Y
2022/ ?; h; H* R2 q# P: W0 Y9 y
Certifificate Authority Cup International Mathematical Contest Modeling # a0 U8 r; e$ }7 a; C/ y7 Lhttp://mcm.tzmcm.cn5 B5 H' S0 c5 A
Problem D (ICM)+ O! h! E+ n- n- P* i
Whether Wildlife Trade Should Be Banned for a Long3 H1 @& u! K* ?* a8 n
Time 7 V# z$ h" v% J: K" IWild-animal markets are the suspected origin of the current outbreak and the & _* l: E) K( ?2002 SARS outbreak, And eating wild meat is thought to have been a source& ] Z+ W5 R4 z6 d7 E3 V' z1 w9 l3 K
of the Ebola virus in Africa. Chinas top law-making body has permanently) ^8 l) }9 I5 m, Z, q( g
tightened rules on trading wildlife in the wake of the coronavirus outbreak, ( d, G' ^% ?0 B6 J. a. gwhich is thought to have originated in a wild-animal market in Wuhan. Some % K$ f! B- M5 N" a0 K. g2 N% Q: bscientists speculate that the emergency measure will be lifted once the outbreak 7 Q: g) {1 T! j# G% k7 hends. 9 S+ u X) H- |4 ]0 pHow the trade in wildlife products should be regulated in the long term?$ r" h0 R G# f+ |6 ]3 x; m
Some researchers want a total ban on wildlife trade, without exceptions, whereas" H [; D- U0 J; r4 f
others say sustainable trade of some animals is possible and benefificial for peo w# o) v( L& `' w. d0 H0 b: u
ple who rely on it for their livelihoods. Banning wild meat consumption could6 i4 a9 _; j) i4 C
cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil 4 h& Z7 O' }. X Ylion people out of a job, according to estimates from the non-profifit Society of1 x& P" E( e" J+ P3 J
Entrepreneurs and Ecology in Beijing.5 v- D/ Y( {# W. j
A team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology 9 x/ f C+ I8 R/ B. D: t5 hin China, chasing the origin of the deadly SARS virus, have fifinally found their $ U$ I$ H* f1 `, h6 o0 wsmoking gun in 2017. In a remote cave in Yunnan province, virologists have : \) n" `1 S, P2 Pidentifified a single population of horseshoe bats that harbours virus strains with & X T4 m$ c2 q* Z* p! u; Q! j2 Qall the genetic building blocks of the one that jumped to humans in 2002, killing % w) p+ `! s4 Jalmost 800 people around the world. The killer strain could easily have arisen . ?5 v2 w4 F9 t: }from such a bat population, the researchers report in PLoS Pathogens on 30 ! l/ G C1 K+ I# d! r. KNovember, 2017. Another outstanding question is how a virus from bats in0 _# U5 C1 D& X9 @
Yunnan could travel to animals and humans around 1,000 kilometres away in- D2 V* Y( H( {* R& ~) u: W
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife, U2 ?% J5 y0 x
trade is the answer. Although wild animals are cooked at high temperature % {1 V8 p* N0 k+ ~5 [. c; Zwhen eating, some viruses are diffiffifficult to survive, humans may come into contact2 D% _2 \! e8 d
with animal secretions in the wildlife market. They warn that the ingredients1 g2 F3 _# R/ @8 }/ ?
are in place for a similar disease to emerge again. 5 |1 D; b8 y5 _7 U. \+ z* bWildlife trade has many negative effffects, with the most important ones being: 7 h' U& W! O; M W0 o, B1Figure 1: Masked palm civets sold in markets in China were linked to the SARS : D4 @! ]+ |! K2 l8 v. J2 J Eoutbreak in 2002.Credit: Matthew Maran/NPL ; C4 s5 X5 j2 c7 m: h+ @& D8 }• Decline and extinction of populations & D. n+ D/ l8 z: d' O• Introduction of invasive species - n4 E7 V- F' ]7 a- w; F• Spread of new diseases to humans % `) A0 g2 d' m: k, a7 B/ yWe use the CITES trade database as source for my data. This database + Z0 p' ~4 N8 e3 J: }contains more than 20 million records of trade and is openly accessible. The $ @+ @* K2 M) ~appendix is the data on mammal trade from 1990 to 2021, and the complete 3 T* j) `; d2 g: Q; U( a3 R. { edatabase can also be obtained through the following link: 6 e8 J; q/ h- C; uhttps://caiyun.139.com/m/i?0F5CKACoDDpEJ2 [4 n6 C+ w% D. W2 [; s( n
Requirements Your team are asked to build reasonable mathematical mod ) f( k% A$ o( [( ^' Zels, analyze the data, and solve the following problems:5 Q' t$ u x( A+ N% M& ?
1. Which wildlife groups and species are traded the most (in terms of live+ s: M0 Y- z- k3 n6 D3 X; o% A# N
animals taken from the wild)? : f0 Q+ u' j, C9 Q8 C3 J" p2 y2. What are the main purposes for trade of these animals?* t4 F# q4 G. }( M* g1 r- ?8 \$ i
3. How has the trade changed over the past two decades (2003-2022)?9 a) s+ l3 }; ]/ T
4. Whether the wildlife trade is related to the epidemic situation of major+ `" b# k/ A$ P6 n; J3 |- D/ R
infectious diseases? 6 y( U* B e+ b25. Do you agree with banning on wildlife trade for a long time? Whether it 7 [' s7 `" q% h2 iwill have a great impact on the economy and society, and why? 9 k/ u9 Y0 k* h6 h! J6 s3 K: U" N6. Write a letter to the relevant departments of the US government to explain- m1 t! A& o* V' [
your views and policy suggestions.0 b+ H' W7 ^0 w+ e7 C
2 G+ }0 X) D5 C( L, C6 s0 f- m
) K$ R w* K6 K3 W- ~
y% P# N5 t$ f# v8 J ? + N4 k" a& L; a: a7 x, v $ X$ c! |$ f/ G9 t3 Y% c$ M$ g" j) Z# g8 g W z( x/ w! h