2022小美赛赛题的移动云盘下载地址 2 ~! m# J. {1 b9 F: e( D9 \
https://caiyun.139.com/m/i?0F5CJAMhGgSJx 6 F2 U0 g* |0 P z s# @7 k: |7 e9 B. J& V
20228 o! w4 B/ Y8 n
Certifificate Authority Cup International Mathematical Contest Modeling1 z. \- [7 @# D; F9 [8 c
http://mcm.tzmcm.cn * [+ ?9 e3 Y2 e7 h. FProblem A (MCM)6 a, W+ V# w' q. [/ f
How Pterosaurs Fly / w) m m1 a- C' g3 \Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They$ V2 V- \; b! i$ P& E$ C
existed during most of the Mesozoic: from the Late Triassic to the end of3 I9 q1 _5 _% v* `
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved5 A- d, \: h, r3 S
powered flflight. Their wings were formed by a membrane of skin, muscle, and : `# z- l: s( H2 ?' G( c+ ~other tissues stretching from the ankles to a dramatically lengthened fourth' f9 W+ Z3 ?: b. U
fifinger[1].* y8 ^3 B( k. Y. ^! C4 K
There were two major types of pterosaurs. Basal pterosaurs were smaller ) {- `/ G" Q' a4 m8 R( C0 n- Lanimals with fully toothed jaws and long tails usually. Their wide wing mem % r* L( `3 s$ s4 S; {* |branes probably included and connected the hind legs. On the ground, they 8 h8 I) S: Z; J9 o. }- U# X- l: `would have had an awkward sprawling posture, but their joint anatomy and : A u' P* r8 `$ v) i6 F; jstrong claws would have made them effffective climbers, and they may have lived ! G9 l: k+ l4 Y Qin trees. Basal pterosaurs were insectivores or predators of small vertebrates.3 h& ]& ^# ~7 h
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.' F5 u& i, {2 w' N
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails, + g7 z8 _% \/ c3 ?$ N3 L4 Land long necks with large heads. On the ground, pterodactyloids walked well on * v1 m# Y$ X# {0 ]* h- jall four limbs with an upright posture, standing plantigrade on the hind feet and# q0 D4 @0 {0 d Z3 Y) [1 X) z2 r+ G
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil 1 {! F; W4 v+ Q/ D" Ntrackways show at least some species were able to run and wade or swim[2]. " E3 a+ O: n: iPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which 9 o# Z, i' U: Mcovered their bodies and parts of their wings[3]. In life, pterosaurs would have( Z9 w$ _: ] b1 G$ ~ a9 `
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug$ c. o& e5 E% h+ B
gestions were that pterosaurs were largely cold-blooded gliding animals, de' E% k7 O2 K" k. {; L3 q$ L- \
riving warmth from the environment like modern lizards, rather than burning 5 E- m: ^* L& P/ Tcalories. However, later studies have shown that they may be warm-blooded - Z& ]% L0 a: U! Y( q(endothermic), active animals. The respiratory system had effiffifficient unidirec( y z m$ i/ }' a' q
tional “flflow-through” breathing using air sacs, which hollowed out their bones ; Y) f( {, m3 u% u8 R7 q; V& Oto an extreme extent. Pterosaurs spanned a wide range of adult sizes, from. K5 Q5 |2 }% [9 N
the very small anurognathids to the largest known flflying creatures, including0 J7 q/ {- p8 E, M
Quetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least& X t/ V U- o, n/ A! L5 o
nine metres. The combination of endothermy, a good oxygen supply and strong4 A' m( |/ E B: n- T4 j# C U
1muscles made pterosaurs powerful and capable flflyers. O3 q* N" E8 w, ]1 S# m6 [! JThe mechanics of pterosaur flflight are not completely understood or modeled 7 Z0 v# B( o q0 P2 \- x8 fat this time. Katsufumi Sato did calculations using modern birds and concluded0 m. |8 R W/ p! j4 X
that it was impossible for a pterosaur to stay aloft[6]. In the book Posture,7 R% P% h0 J- q4 @
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able 5 U6 G$ \- [( E+ V1 D* I3 Zto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].( d3 `# |8 F+ `+ Q5 N
However, both Sato and the authors of Posture, Locomotion, and Paleoecology. t7 J9 @3 `% n
of Pterosaurs based their research on the now-outdated theories of pterosaurs + D4 E3 {( y/ Ebeing seabird-like, and the size limit does not apply to terrestrial pterosaurs, 5 u% i6 e G4 o$ K6 U) U: V) S7 Psuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that; m, z* }, Y6 s4 P( `, C
atmospheric difffferences between the present and the Mesozoic were not needed% t( j; f' a+ M% W. K# Z" L) u7 |! G0 X: ]
for the giant size of pterosaurs[8].0 L, z: I$ i4 d5 S. J A* q7 `
Another issue that has been diffiffifficult to understand is how they took offff.& Z6 C# F! B5 [
If pterosaurs were cold-blooded animals, it was unclear how the larger ones: b1 j1 U4 l. R( ~
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage2 f/ Q7 z0 u5 a$ l9 L# S6 p; H
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for' h& X& t, u9 H/ T( t0 C% U
getting airborne. Later research shows them instead as being warm-blooded: |3 Y' ^" d* ~& h, q7 l1 X
and having powerful flflight muscles, and using the flflight muscles for walking as $ e# v2 I8 o8 {quadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of# C' y% q+ W& [: R4 C* C
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism 8 Y J& Z5 |- Z. z! oto obtain flflight[10]. The tremendous power of their winged forelimbs would 9 W7 A# G: s" j' ?. `enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds 4 v% J+ o# m7 [3 S9 R0 Kof up to 120 km/h and travel thousands of kilometres[10].. i6 A& u( T. r. o
Your team are asked to develop a reasonable mathematical model of the; L- [8 P) u1 M* z" E* a) c* y
flflight process of at least one large pterosaur based on fossil measurements and 8 Y& C- R9 t& }' @& f2 \6 xto answer the following questions.+ A3 }$ b& {4 p1 y# w
1. For your selected pterosaur species, estimate its average speed during nor8 w, K! \: J+ ?3 [6 Y7 I+ t. x
mal flflight.7 S7 K7 B& P1 @
2. For your selected pterosaur species, estimate its wing-flflap frequency during3 w0 W# c4 A$ o1 e- r" W
normal flflight. 6 z# ~1 a1 Q& J" @' ^- H2 ^' Y, j3. Study how large pterosaurs take offff; is it possible for them to take offff like 3 w: }$ u4 y6 B, ]% ebirds on flflat ground or on water? Explain the reasons quantitatively. 8 Q2 V6 K& q1 a# g/ b; i# ^References " j( s1 C( h: E( M t[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight & q" P4 i% g3 P/ WMembrane. Acta Palaeontologica Polonica. 56 (1): 99-111.# @# A" v# S- |: }1 [
2[2] Mark Witton. Terrestrial Locomotion. : x: L8 H) j D' _https://pterosaur.net/terrestrial locomotion.php$ p2 K% m# [0 `" u3 q
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs( m( s7 r: p0 J& s% l) w
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324- {2 @9 x4 S) {. z" ]- V4 Q
pterosaurs-had-feathers.html# g, p! I7 `3 }' R
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a$ x$ w0 a6 k$ J+ m
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) . ]3 Q* i2 m5 j- g. n, K, W+ z/ W7 n" Qfrom China. Proceedings of the National Academy of Sciences. 105 (6):2 ~ c: ^5 K6 _9 E3 ~+ G
1983-87. / h- t4 G7 ?2 Y# f) T[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust+ h! r, K: ]9 X J0 B
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):7 N5 o k2 J- Y# C2 _ q/ I
180-84." s3 g/ g. v5 C5 {
[6] Devin Powell. Were pterosaurs too big to flfly?% x- Y8 G" W( s% T o
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs ! u$ a C, S3 @, c" itoo-big-to-flfly/ 7 U9 f1 s; \( M0 E( ~& @[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology - J: u% \) k; F3 k) ?$ wof pterosaurs. Boulder, Colo: Geological Society of America. p. 60. - d8 }* Y/ B$ t$ F' y[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable0 A2 @/ [3 P9 ~2 [
air sacs in their wings.# y; a( R. {& s
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur: Y# ?( t5 c D: k, |. |
breathing-air-sacs& M+ |! d9 |# R- \
[9] Mark Witton. Why pterosaurs weren’t so scary after all.* g4 |& m$ F$ F) j
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils6 `$ u. I6 n) u% B5 S9 f
research-mark-witton 3 A3 J5 N4 X8 ^; U2 s* F[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? 9 i$ F5 t! H8 @0 \- Shttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs* O+ C l1 D z5 W
vault-aloft-like-vampire-bats/( X; [. g" @, Q7 G8 i, n
& s+ A2 O+ R: j9 m$ b2022. ?- a! e" P+ u% G& K
Certifificate Authority Cup International Mathematical Contest Modeling2 m) @. ~( t- w6 J
http://mcm.tzmcm.cn + Q$ S! ^4 e/ Y' g9 z) q6 zProblem B (MCM)6 J- ^" `( g; r1 u" w3 k
The Genetic Process of Sequences) c9 \# q: L+ V5 y( E/ X
Sequence homology is the biological homology between DNA, RNA, or protein : E: z7 m) b. j9 o# G0 O6 h, f' C7 Tsequences, defifined in terms of shared ancestry in the evolutionary history of ) W4 F n( ?$ v5 f1 M+ ]life[1]. Homology among DNA, RNA, or proteins is typically inferred from their 3 H+ h& f/ W5 b5 w! pnucleotide or amino acid sequence similarity. Signifificant similarity is strong/ \+ N+ G: |5 |" m! }1 E- z
evidence that two sequences are related by evolutionary changes from a common Q" m& \" ~ y- B- J$ h! o2 Hancestral sequence[2]. ( N) |, t0 G- v6 ~8 iConsider the genetic process of a RNA sequence, in which mutations in nu : R' n6 Z3 Y5 F6 N% [! zcleotide bases occur by chance. For simplicity, we assume the sequence mutation 9 b& g" C; l( s; x! G; x" {arise due to the presence of change (transition or transversion), insertion and 9 W% h4 o4 |5 c+ h% Q' R, mdeletion of a single base. So we can measure the distance of two sequences by # e! h! z* u9 _) u, l# Hthe amount of mutation points. Multiple base sequences that are close together& }& n; d, D+ f
can form a family, and they are considered homologous. / X; V) s; P: FYour team are asked to develop a reasonable mathematical model to com y- t/ \* @1 D$ k" [5 U
plete the following problems. 5 h4 P1 f: q8 D# H7 K1. Please design an algorithm that quickly measures the distance between/ X/ N' y, W. W9 U) c" R1 r
two suffiffifficiently long(> 103 bases) base sequences.% ^5 P, j" V/ {) L
2. Please evaluate the complexity and accuracy of the algorithm reliably, and0 C( ^/ v9 _7 P5 V5 B/ ^! X
design suitable examples to illustrate it.' I) [- `7 z N3 [1 [7 f" q" A
3. If multiple base sequences in a family have evolved from a common an i* b; K6 Z, x7 jcestral sequence, design an effiffifficient algorithm to determine the ancestral 0 o/ a% j* w8 {2 n$ o2 z& Tsequence, and map the genealogical tree.5 ~0 |- X4 n( [( T* r* f! A9 n1 E
References8 G4 g6 o: V' @/ D
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re% ?8 u, C" s2 Z' Y5 m2 K9 I
view of Genetics. 39: 30938, 2005. 8 k* t0 P2 o. q6 Z [[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,& k2 m/ Q2 a8 ]) d! D; D) j) E" }
et al. “Homology” in proteins and nucleic acids: a terminology muddle and% S; W l) [ |6 E
a way out of it. Cell. 50 (5): 667, 1987.! g. o) _+ C: g6 M" u- X
: b0 z( d7 n/ W* Z6 a7 f1 d2022' J1 r3 _8 w" w R& {2 i
Certifificate Authority Cup International Mathematical Contest Modeling6 _7 z2 n8 u3 V8 \
http://mcm.tzmcm.cn0 M- h: L" z' M! o m
Problem C (ICM) 7 K, }' U( ^) ]! `Classify Human Activities 9 s/ Z( y- {8 y$ ~& COne important aspect of human behavior understanding is the recognition and ' r! @2 R1 L' B% V% C. ?5 C) |monitoring of daily activities. A wearable activity recognition system can im " _7 N/ o' k4 m* f. d. r0 K2 kprove the quality of life in many critical areas, such as ambulatory monitor% K* Q4 S8 j, o
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ W$ {" P: }* K
ity recognition systems are used in monitoring and observation of the elderly & v9 e6 N2 m0 gremotely by personal alarm systems[1], detection and classifification of falls[2], P6 [: F8 f+ V0 \" H& emedical diagnosis and treatment[3], monitoring children remotely at home or in1 q1 c4 U# Q! L8 y z, F% t$ f
school, rehabilitation and physical therapy , biomechanics research, ergonomics, $ v' g/ p4 ^/ U) X8 [, Qsports science, ballet and dance, animation, fifilm making, TV, live entertain6 |# Z" z) m$ c3 T) e8 W) s5 l
ment, virtual reality, and computer games[4]. We try to use miniature inertial( o" p' d3 a8 ~5 T8 y5 _; |
sensors and magnetometers positioned on difffferent parts of the body to classify1 Y: p& C7 j2 U6 L, Q7 s. P
human activities, the following data were obtained.( t u Z" F( e0 S( w
Each of the 19 activities is performed by eight subjects (4 female, 4 male,9 R+ p+ q1 a* C s$ H# X, E
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes 1 T& D- Z$ h/ k3 Tfor each activity of each subject. The subjects are asked to perform the activ , P6 p c) h$ ^6 d# ]ities in their own style and were not restricted on how the activities should be! J# l7 c) a* B3 q
performed. For this reason, there are inter-subject variations in the speeds and. Q+ Z4 i2 x% m
amplitudes of some activities. & R# b! N3 h6 _Sensor units are calibrated to acquire data at 25 Hz sampling frequency.# t. P0 E8 i: b, ^, z2 X6 F" H3 J
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal ; b _- I7 r/ I# ~segments are obtained for each activity. % ~6 a x( P$ ?7 \ ^+ k$ zThe 19 activities are: & r, M) o1 f; A: `- {1. Sitting (A1); % t8 W3 i- e- A4 K4 X2. Standing (A2); 4 p4 x, P: z5 }' z; z6 j3. Lying on back (A3);2 R* x0 O5 j* {2 t9 I
4. Lying on right side (A4); + b6 D% d+ ^2 \% H" ?: @8 @# Z3 X5. Ascending stairs (A5);* M' B* P3 W2 v* R4 x+ `
16. Descending stairs (A6);! a( F% w7 d+ N, ]0 i
7. Standing in an elevator still (A7); ( G# d6 W/ F* o6 L# E8. Moving around in an elevator (A8); ! n0 o" b& L) `1 ~" z; _+ c9. Walking in a parking lot (A9); 2 a T6 J6 E0 Z10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg c) x0 z1 N7 c4 q1 C! \* _
inclined positions (A10); 7 _3 ^0 k" n) S/ V11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions0 g( x6 F2 k! q" n8 s9 Q
(A11);/ ]* `1 J A c/ ^0 x, I5 J
12. Running on a treadmill with a speed of 8 km/h (A12);9 o$ d( V7 \( G q& E9 [" V
13. Exercising on a stepper (A13); # {5 ~5 Y. y, D3 G$ Q4 U14. Exercising on a cross trainer (A14); 1 l3 r* u/ e% n* f) X5 y9 c3 Z6 a$ R15. Cycling on an exercise bike in horizontal position (A15); 1 F8 X- i* i6 I16. Cycling on an exercise bike in vertical position (A16); . w3 ]# M$ K# H" Q0 t- g/ F17. Rowing (A17);% C7 ^6 s; K: [( w" B6 v
18. Jumping (A18); $ q; p# E8 ~. E- o i) [# v. R9 {" Q0 E19. Playing basketball (A19).) v, J: C+ Z1 v; C2 a" a
Your team are asked to develop a reasonable mathematical model to solve / {, f. m2 @( Y& hthe following problems. & P: G1 N) I% F1. Please design a set of features and an effiffifficient algorithm in order to classify / }/ n* M. ~6 [the 19 types of human actions from the data of these body-worn sensors.! B/ s, U; y+ i. s7 f
2. Because of the high cost of the data, we need to make the model have 9 \# m5 r' _0 ?$ l0 ha good generalization ability with a limited data set. We need to study2 i4 E0 u, u% z1 A( \2 R
and evaluate this problem specififically. Please design a feasible method to 5 i5 C$ K! _0 H; W' y8 oevaluate the generalization ability of your model. 1 E/ p1 c. U- Q0 b* |; q3. Please study and overcome the overfifitting problem so that your classififi- # B6 d0 d3 X8 E, i5 _" W) Z2 \cation algorithm can be widely used on the problem of people’s action 0 `; H, c! p5 p" w4 @, V0 Y3 ^classifification. . _) E2 j- r5 \. xThe complete data can be downloaded through the following link: $ i. D x. V. E( y! Shttps://caiyun.139.com/m/i?0F5CJUOrpy8oq; b6 ^6 U& v2 W9 E
2Appendix: File structure% E* t3 N8 K+ F: \" W4 O1 V
• 19 activities (a) 8 h r, m1 S' K2 x8 E6 z• 8 subjects (p) 8 z& o' C l; w# ?1 x• 60 segments (s) 7 R6 O2 o8 N" Y1 c2 }• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left . S/ M. f/ y6 g: b4 Tleg (LL) 5 N F m- J' H5 F• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z % d t5 p" J( s/ a# t1 f) p( J5 Emagnetometers)- Z3 t! Y! F- B# |2 x' q N( U
Folders a01, a02, ..., a19 contain data recorded from the 19 activities. 5 y% L* `/ W, D$ s+ B- @( tFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the ) x6 b' h8 d" g( q3 [# b8 subjects.! b' e* L1 p6 ~
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each6 ~( M! A& U/ E
segment. 1 @* f6 f5 H4 @ o& cIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25( s! k" p% ]: B4 G2 l) S
Hz = 125 rows. : C. [% [7 D7 s2 R" _Each column contains the 125 samples of data acquired from one of the1 J7 ]1 Y0 l f$ A, ^
sensors of one of the units over a period of 5 sec. / Y! d) d5 F' _& C6 X+ OEach row contains data acquired from all of the 45 sensor axes at a particular 2 f9 m) v$ T& L+ j& L; ]sampling instant separated by commas. 7 L: R. J* V) G- _9 n- NColumns 1-45 correspond to:4 u$ u7 |% O/ T. j/ u0 |2 t
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag,1 m s, }$ n8 X$ ?" u! d
• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, 9 Z9 p: r$ `" W$ ]' ^• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag,: ]% e! @0 Z7 Q
• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,3 }8 @; F2 n U; c* z3 g
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.7 P+ R+ h6 z" ?1 f4 Z# u/ V0 j
Therefore, 4 U- x3 [: N! `5 P; U6 N& R% d4 F$ d• columns 1-9 correspond to the sensors in unit 1 (T),7 n- D8 F9 K7 M
• columns 10-18 correspond to the sensors in unit 2 (RA),4 S- Y3 q7 @4 I* F6 x6 J. E
• columns 19-27 correspond to the sensors in unit 3 (LA), ( H& z, P2 L9 N# S3 H• columns 28-36 correspond to the sensors in unit 4 (RL),$ k; `$ d6 o! `+ s" Q# A/ d! l' y
• columns 37-45 correspond to the sensors in unit 5 (LL).# g) k6 F# I4 d0 C
3References ; n9 x h( [. {( p7 j. J1 e3 o[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic + x+ \. Z( F/ Q7 g8 qdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. ; G9 v) k9 R3 G" b* e" r42(5), 679-687, 2004 7 ]7 Y7 a% h) K7 E; B9 }" {2 `' {9 E; a[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of" d) j$ F* w+ \8 J+ Z
low-complexity fall detection algorithms for body attached accelerometers.- k |% W1 z1 p" T/ l5 L1 c1 K
Gait Posture 28(2), 285-291, 2008" D% r/ }: h1 m+ G j% ^7 H8 M
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag# G" T. E" E" N3 }2 q. Q( B
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol. & v" ?; f4 n; n: [6 G9 K% RB. 11(5), 553-562, 2007 . d4 f8 K# @ U4 C4 g8 H[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con$ b! I4 \$ v9 H8 E% m9 n# @7 O% T/ f
trol of a physically simulated character. ACM T. Graphic. 27(5), 2008% ~( s% e! j0 V1 U" y: _
: y, {5 n& H: g9 f# ]: I2 G' ?
2022 7 H- |/ T! n* sCertifificate Authority Cup International Mathematical Contest Modeling7 u% `! _$ c+ C2 L( K |
http://mcm.tzmcm.cn1 a+ ]0 t6 `9 q% J6 [. q
Problem D (ICM)+ \4 m% V% p& B8 u, y+ n$ W! Q
Whether Wildlife Trade Should Be Banned for a Long+ R/ M \- T) B
Time 9 o! A7 l0 s- H. d6 I: f& oWild-animal markets are the suspected origin of the current outbreak and the ! Y9 @- n5 H; K8 }* a% R: o2002 SARS outbreak, And eating wild meat is thought to have been a source 1 F) [1 H6 |7 |: Y; V: u \of the Ebola virus in Africa. Chinas top law-making body has permanently& f4 |, ~* Z- n3 z3 l" w
tightened rules on trading wildlife in the wake of the coronavirus outbreak, U* P( R2 }" T6 v9 @4 [$ J! v
which is thought to have originated in a wild-animal market in Wuhan. Some( |8 R3 ]- p+ j3 q' r
scientists speculate that the emergency measure will be lifted once the outbreak0 K: r( A) k1 _; J. j! C* D
ends. : i1 E! o ~4 h) KHow the trade in wildlife products should be regulated in the long term? ( W0 i: P2 u0 d- V+ JSome researchers want a total ban on wildlife trade, without exceptions, whereas . ~3 i+ b5 K1 U8 o* vothers say sustainable trade of some animals is possible and benefificial for peo ! o+ N" g* L# @# b/ X% Jple who rely on it for their livelihoods. Banning wild meat consumption could / N$ w) \! G0 O' @; @6 d3 a4 r& icost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil( D2 x3 Q5 `. p' L1 q
lion people out of a job, according to estimates from the non-profifit Society of 3 K4 j6 P- h& P- ~) |5 |5 p! pEntrepreneurs and Ecology in Beijing. 7 Y. Y6 w0 u! H$ t' BA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology % Z9 y; x% E) `1 Z8 m9 Bin China, chasing the origin of the deadly SARS virus, have fifinally found their ' ~, Q0 c. f4 b. c) I8 w q w( Ssmoking gun in 2017. In a remote cave in Yunnan province, virologists have ) p# l) d+ ?, J$ zidentifified a single population of horseshoe bats that harbours virus strains with& A3 E- q* D! [2 [, Z3 F* s
all the genetic building blocks of the one that jumped to humans in 2002, killing 3 A+ d( L3 g F5 v+ q' _almost 800 people around the world. The killer strain could easily have arisen; j8 h g" V3 ]) W7 ^' g% T) y
from such a bat population, the researchers report in PLoS Pathogens on 303 J' T5 y& H8 u5 d* G! @
November, 2017. Another outstanding question is how a virus from bats in 2 Q1 q r6 z/ [+ p1 F* @Yunnan could travel to animals and humans around 1,000 kilometres away in3 p% l2 I+ P& p* j+ T6 H
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife, n1 X8 L, I: T) E+ t
trade is the answer. Although wild animals are cooked at high temperature0 y# Y" |! X4 |; u
when eating, some viruses are diffiffifficult to survive, humans may come into contact' d0 U `- F$ f
with animal secretions in the wildlife market. They warn that the ingredients% q/ ?, O4 H J5 |0 G
are in place for a similar disease to emerge again.3 M; ?1 o1 \ I/ p
Wildlife trade has many negative effffects, with the most important ones being: ^" [+ s7 w) j0 M2 a$ E1Figure 1: Masked palm civets sold in markets in China were linked to the SARS" A- g8 Z0 y; }, `% R8 |) ~
outbreak in 2002.Credit: Matthew Maran/NPL4 K0 V4 ~$ Z/ z3 r
• Decline and extinction of populations ; L" c- I; a7 K, z2 I0 K/ z• Introduction of invasive species / l& L3 @. i6 }• Spread of new diseases to humans , |' [" ~ {1 j8 W+ ?4 X" jWe use the CITES trade database as source for my data. This database 3 T& }& x$ H$ B( W3 @& \contains more than 20 million records of trade and is openly accessible. The! `* z- C, m, b
appendix is the data on mammal trade from 1990 to 2021, and the complete$ g1 ~* C( A- H
database can also be obtained through the following link:4 R N/ U2 `! n2 ]
https://caiyun.139.com/m/i?0F5CKACoDDpEJ* h) j3 _! W& q
Requirements Your team are asked to build reasonable mathematical mod 5 s7 {1 x* d0 Y+ i6 Qels, analyze the data, and solve the following problems:; x! x& _) n: {2 h% ^( D0 Y L; Y
1. Which wildlife groups and species are traded the most (in terms of live $ X5 S) s$ u% n+ m- C- L, ganimals taken from the wild)?+ T. ~: I4 B+ e; n: ^
2. What are the main purposes for trade of these animals? 2 q8 B( W4 N1 p9 K7 P: V3. How has the trade changed over the past two decades (2003-2022)?1 T! E" k+ @* Q, o; W/ P& ?) R+ ]
4. Whether the wildlife trade is related to the epidemic situation of major 8 S5 j1 p! A5 U0 }infectious diseases? 2 a0 W& m: a8 l25. Do you agree with banning on wildlife trade for a long time? Whether it/ ~6 t8 ]$ w$ R& U5 P
will have a great impact on the economy and society, and why?/ b. _; K3 ?8 t* u
6. Write a letter to the relevant departments of the US government to explain ^: `) W" O T5 K& Xyour views and policy suggestions.- C$ w- b/ w8 W! d/ g1 N8 z