2022小美赛赛题的移动云盘下载地址 5 e- I) D" v$ j: z' Fhttps://caiyun.139.com/m/i?0F5CJAMhGgSJx9 b) e: l! `( D' w5 O9 s
, t b' c1 m5 [) @/ B6 S g2022 / h. \- N2 B+ I; P5 i% v9 B4 b$ tCertifificate Authority Cup International Mathematical Contest Modeling% ^) F) Q+ Y; A- f* P3 Y' k$ h. n
http://mcm.tzmcm.cn& h) V, ^/ R$ v; H* N
Problem A (MCM) ! j) G6 e& ^1 k3 b R, ZHow Pterosaurs Fly+ ?- h9 x8 q' c& ?6 ~# w
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They 5 w9 V {( s$ cexisted during most of the Mesozoic: from the Late Triassic to the end of- c5 h! \! u$ Z) T! x0 x" o |
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved9 G; W" Q4 s9 E6 S5 O0 n3 ]1 d
powered flflight. Their wings were formed by a membrane of skin, muscle, and ' x/ U8 y4 x/ q+ B$ L/ A6 Gother tissues stretching from the ankles to a dramatically lengthened fourth8 \8 e, ?0 Q. N3 z/ r
fifinger[1]. & a E. }6 j5 g0 K/ V( P! O9 ZThere were two major types of pterosaurs. Basal pterosaurs were smaller 2 j: [) A2 H5 Danimals with fully toothed jaws and long tails usually. Their wide wing mem) D; w" x( a+ x" [8 i# }
branes probably included and connected the hind legs. On the ground, they 2 w9 d/ p. P! h R# cwould have had an awkward sprawling posture, but their joint anatomy and 5 m9 O5 @. W4 K, Z. rstrong claws would have made them effffective climbers, and they may have lived 4 i/ b1 N* ? @7 @6 {$ ^in trees. Basal pterosaurs were insectivores or predators of small vertebrates.) f0 S) H# d1 T0 H$ N
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles." V1 Y( o7 {1 `6 t
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails, 2 s3 e. Q$ N; h$ ^7 v8 Oand long necks with large heads. On the ground, pterodactyloids walked well on ! @) Q5 J; Y# Y* iall four limbs with an upright posture, standing plantigrade on the hind feet and: S" Q1 ^9 `4 R+ Y
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil k# L: d% J9 R6 c$ y% W7 M
trackways show at least some species were able to run and wade or swim[2].9 S0 z8 N7 x" W- Z' J! ]# [) P
Pterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which8 O1 |9 J) Z- q0 u8 q0 D" Y* T
covered their bodies and parts of their wings[3]. In life, pterosaurs would have/ a' x& T, o6 ^% W$ ]
had smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug+ n0 p+ z( h# r7 d* h9 T
gestions were that pterosaurs were largely cold-blooded gliding animals, de ( }' V0 G& y3 B0 o7 Griving warmth from the environment like modern lizards, rather than burning( }! K/ k8 a( Z7 U" w, g
calories. However, later studies have shown that they may be warm-blooded) _ i8 a" w- m
(endothermic), active animals. The respiratory system had effiffifficient unidirec( _: W5 T4 y5 W1 X8 Z. H" I
tional “flflow-through” breathing using air sacs, which hollowed out their bones : W- u0 A+ o- l* `" f5 S/ W; hto an extreme extent. Pterosaurs spanned a wide range of adult sizes, from 4 \3 N% j9 r& I' ?4 f" w4 v9 Ithe very small anurognathids to the largest known flflying creatures, including 0 C$ V; \( H3 s0 G9 EQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least 5 ^ X+ j1 t2 Cnine metres. The combination of endothermy, a good oxygen supply and strong: Y" Y: M, N, [: L6 W. w4 n
1muscles made pterosaurs powerful and capable flflyers. " ?$ D$ S" n5 |The mechanics of pterosaur flflight are not completely understood or modeled c& a, r5 V% l! R3 `
at this time. Katsufumi Sato did calculations using modern birds and concluded , F4 e2 A5 Z6 wthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture,8 r& @* s* A' \
Locomotion, and Paleoecology of Pterosaurs it is theorized that they were able! }* w0 A8 A7 O# m5 D! _: D9 Q
to flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7]. 7 }: ~ U+ N3 i# L$ m1 y- {0 LHowever, both Sato and the authors of Posture, Locomotion, and Paleoecology( L- o" q! y4 i, G8 Q( h7 o
of Pterosaurs based their research on the now-outdated theories of pterosaurs ( n: ^9 Y, |$ B- v3 w0 Z! Y7 |being seabird-like, and the size limit does not apply to terrestrial pterosaurs, " G' q# S4 a4 B P' M) J7 asuch as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that6 k( L; B* X9 q5 S/ e! A9 C+ Y3 S/ y
atmospheric difffferences between the present and the Mesozoic were not needed5 j8 V0 o2 y2 x; V7 X
for the giant size of pterosaurs[8].: r: @5 h1 N- {) |
Another issue that has been diffiffifficult to understand is how they took offff. 4 w& s' \3 ?- V- \+ uIf pterosaurs were cold-blooded animals, it was unclear how the larger ones: U- r0 V P U* h8 |" m
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage 7 o- j: J/ P/ Ra bird-like takeoffff strategy, using only the hind limbs to generate thrust for - P' \# y o: i: \6 B, o3 _getting airborne. Later research shows them instead as being warm-blooded- J: p/ M' E. g+ M1 w7 G
and having powerful flflight muscles, and using the flflight muscles for walking as + y/ w! N% V( [+ N2 equadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of* O7 t9 s% x, V
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism0 g8 t8 c0 ^! i9 v" F8 c
to obtain flflight[10]. The tremendous power of their winged forelimbs would 7 V7 z4 z! G; Z2 j0 V8 G- Zenable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds2 `: f! L6 m; y& H
of up to 120 km/h and travel thousands of kilometres[10]. 2 l2 c) n& L# @Your team are asked to develop a reasonable mathematical model of the ' m- \$ U; T) o/ Qflflight process of at least one large pterosaur based on fossil measurements and- |/ t. a- }" K8 k; f( v* v# H
to answer the following questions. $ J5 b" |: k: p& U; u+ B1. For your selected pterosaur species, estimate its average speed during nor) j1 K$ M" T) D; L# O$ F
mal flflight. 1 K. k* ^* x: s2 {- q2. For your selected pterosaur species, estimate its wing-flflap frequency during & n* e! i; T. u% h) r! dnormal flflight.) i! ]" c$ f6 o; G- J) W, w
3. Study how large pterosaurs take offff; is it possible for them to take offff like+ d+ ]& A5 t# R; L% x) [
birds on flflat ground or on water? Explain the reasons quantitatively., Y5 s( _ |" a* n: A
References# S/ N0 D `; M2 X3 j
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight% K5 H; N; t0 O; S) z( L
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111. ' _: v! k0 ?2 P+ C8 u2[2] Mark Witton. Terrestrial Locomotion. ) R; O. _" S E1 }3 O% B8 U' Rhttps://pterosaur.net/terrestrial locomotion.php/ H# u3 ? V: I% J
[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs + m/ K# [# M3 z# x, dWere Covered in Fluffffy Feathers. https://www.livescience.com/64324- : ?1 P; Z* [. Y0 B: rpterosaurs-had-feathers.html7 J1 C+ L% J5 S! p# N$ p' a
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a ( A. n) J( h7 M' t4 Krare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea) ! u. ^" X' R# t! wfrom China. Proceedings of the National Academy of Sciences. 105 (6):+ r2 Z+ q! K2 P' M, i/ y
1983-87. * ~5 x. P0 @( |$ A6 z2 X7 \5 K[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust ; {( o& b; c1 _skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):3 [8 _+ l) |$ j5 h8 o
180-84. . P) t) F* {3 r% `0 N1 F3 J9 B+ T[6] Devin Powell. Were pterosaurs too big to flfly?/ P$ |, g! S q, Q
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs* `9 O8 O3 Y, ?0 l
too-big-to-flfly// z5 @' h r& {: x: ~
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology+ B, ~+ C1 U H2 O
of pterosaurs. Boulder, Colo: Geological Society of America. p. 60./ ?4 _5 i$ _2 P
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable 2 v' m; p; E3 g) p; Q# D6 ?# {air sacs in their wings.2 S4 {1 W( Q/ j2 B: S7 \+ g3 U/ c
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur+ o, O% S; `' c; Q5 c
breathing-air-sacs / {1 L( w1 g. A h# o[9] Mark Witton. Why pterosaurs weren’t so scary after all.7 c+ j1 j, w9 h
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils4 B# \/ n9 M* E8 h, F- v- |
research-mark-witton 6 a; T6 f5 {2 d$ t: @( s7 Y* f/ ~[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats? ! J/ w0 F" m% o, M! L- uhttps://www.newscientist.com/article/dn19724-did-giant-pterosaurs! j) G' s( ~4 {" A2 R
vault-aloft-like-vampire-bats/ ( t# F- d+ R" R& ? ( d' `# ?- \; i5 U4 C( `: f* L8 e2022 : t) N1 b4 `9 B4 m5 _( @( e$ z9 eCertifificate Authority Cup International Mathematical Contest Modeling . z/ ?# _& F4 d3 [http://mcm.tzmcm.cn # W/ s9 s/ I) p9 \- oProblem B (MCM)& _- f! x5 b% S1 B
The Genetic Process of Sequences+ a+ \1 _( D# ]5 F
Sequence homology is the biological homology between DNA, RNA, or protein1 Q# T3 v$ v7 m8 Z
sequences, defifined in terms of shared ancestry in the evolutionary history of 4 f5 I1 m0 e7 b' plife[1]. Homology among DNA, RNA, or proteins is typically inferred from their 0 h5 n# n b. y$ ynucleotide or amino acid sequence similarity. Signifificant similarity is strong ! [$ ?; t) i% t+ x4 b" devidence that two sequences are related by evolutionary changes from a common$ |* _, D. u" L l! H" _
ancestral sequence[2]. ! W0 s z! S6 K; }; W- |( zConsider the genetic process of a RNA sequence, in which mutations in nu/ T1 m; }* d: T/ H& D0 S
cleotide bases occur by chance. For simplicity, we assume the sequence mutation + b+ s; e- @ [$ X* rarise due to the presence of change (transition or transversion), insertion and & v' k* w. @! q2 vdeletion of a single base. So we can measure the distance of two sequences by $ r1 k- x+ A. d' wthe amount of mutation points. Multiple base sequences that are close together * z1 O( M& e/ l5 x, }3 k9 h2 ecan form a family, and they are considered homologous. % ~5 ]9 v& `) R+ X, D* iYour team are asked to develop a reasonable mathematical model to com 3 G1 H4 m% c+ i+ lplete the following problems.2 H* R( s* d$ K; I
1. Please design an algorithm that quickly measures the distance between , s' ]/ I7 y6 ctwo suffiffifficiently long(> 103 bases) base sequences.5 e5 p; U( }3 e) a, k! i
2. Please evaluate the complexity and accuracy of the algorithm reliably, and 2 k, _7 A5 Z; [4 P) j9 [6 Sdesign suitable examples to illustrate it.+ g% G" U o- T! d9 Q) `
3. If multiple base sequences in a family have evolved from a common an , F' l% i2 p! Y6 Jcestral sequence, design an effiffifficient algorithm to determine the ancestral ; p- e% t* @' J( A' Hsequence, and map the genealogical tree. / l9 s4 V0 z8 q9 ~% fReferences, k/ k4 K, K( E4 a) s4 L
[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re + j7 b* n( n) n% q! tview of Genetics. 39: 30938, 2005., j4 a6 @% B: \
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,2 S2 P1 S- F9 G% p1 j# B6 F
et al. “Homology” in proteins and nucleic acids: a terminology muddle and9 x9 t9 }2 }: A, Q2 t0 k
a way out of it. Cell. 50 (5): 667, 1987.( ?4 C* E) Y8 M7 p
( v8 E) u* C7 y1 H
2022 / w: q6 u8 a2 f9 X2 l6 b6 m! S kCertifificate Authority Cup International Mathematical Contest Modeling& z" l1 |9 V" B2 j/ M
http://mcm.tzmcm.cn1 n% J+ \5 h. U7 N$ p
Problem C (ICM)9 ]* U) |1 Y [7 @- W
Classify Human Activities / _ F; i6 I/ O+ }0 m5 ]One important aspect of human behavior understanding is the recognition and+ \! M q& L0 R# ^" U/ ~
monitoring of daily activities. A wearable activity recognition system can im' v7 x6 o6 I0 a, }0 P
prove the quality of life in many critical areas, such as ambulatory monitor $ g6 l) R) C, O& ^, Y% ?) uing, home-based rehabilitation, and fall detection. Inertial sensor based activ 6 x1 W2 H' e$ {% A- Dity recognition systems are used in monitoring and observation of the elderly! ]) d: G; }+ ^$ d) a* j" B
remotely by personal alarm systems[1], detection and classifification of falls[2], * h- |) [8 R8 W( c) v$ E9 M- ]medical diagnosis and treatment[3], monitoring children remotely at home or in + j. @, a# r! _0 o1 a! Y; v$ ~school, rehabilitation and physical therapy , biomechanics research, ergonomics,$ a5 l0 b2 G$ \5 c0 e( s" v
sports science, ballet and dance, animation, fifilm making, TV, live entertain 3 F7 Q4 \! x8 `" _/ S, I7 Kment, virtual reality, and computer games[4]. We try to use miniature inertial 4 ?3 C% v2 k; r! Vsensors and magnetometers positioned on difffferent parts of the body to classify ) n6 a! O- e' t& E/ k5 o' ]- Mhuman activities, the following data were obtained. 6 F9 W' m+ R9 e( QEach of the 19 activities is performed by eight subjects (4 female, 4 male,9 p3 `6 _: ]5 x. p7 } m) J) p3 \
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes% ~$ L: I- u6 L
for each activity of each subject. The subjects are asked to perform the activ + x- e# e9 A( }ities in their own style and were not restricted on how the activities should be8 `1 H0 v& |- P9 V- O* j
performed. For this reason, there are inter-subject variations in the speeds and 3 f( V& |, {3 l0 h6 \amplitudes of some activities., T/ M' ]; M1 B8 y5 r0 e
Sensor units are calibrated to acquire data at 25 Hz sampling frequency. \& {( `* V- G0 {9 e- ?. x0 oThe 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal+ ~ ]# V2 i! N$ T1 |% @
segments are obtained for each activity.3 j) p/ ^2 ]" S4 J
The 19 activities are: 9 Z* G) V5 Q% f4 }: B; {- D7 C1. Sitting (A1);4 J+ V- Z% k6 b9 T o2 L
2. Standing (A2); ; p' `2 `/ D8 t$ J- J( U3. Lying on back (A3);3 M G& P0 a' Z' M+ c, o
4. Lying on right side (A4); # S J% t7 l. H/ I7 {8 ?$ B5. Ascending stairs (A5);. z" b6 B5 k, C6 J
16. Descending stairs (A6);1 I p) k6 v% t* j& p) k
7. Standing in an elevator still (A7); % r' Y1 C& w( A: D* |- @4 |8. Moving around in an elevator (A8); . R; z8 a, F% v B6 l9. Walking in a parking lot (A9);5 f# Q, d8 Q% n3 \5 \6 I
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg& L$ S/ u& c. S4 D4 R+ ^7 ~$ u
inclined positions (A10);# p4 w5 ]5 y% O1 I
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions0 k' B) J; W. o( b( ]+ f6 ?
(A11); & @: w2 j3 ^$ ?, b6 Z12. Running on a treadmill with a speed of 8 km/h (A12); $ T: Q% H3 k' T% r" U" j* C13. Exercising on a stepper (A13);( E) l. a# m& C. z
14. Exercising on a cross trainer (A14); 0 V _, [7 ?. v- f' Z2 r15. Cycling on an exercise bike in horizontal position (A15);7 o: O; r1 x' `9 q3 g. F- S. @* x
16. Cycling on an exercise bike in vertical position (A16);) p" e/ W& A G1 _6 B! l4 m
17. Rowing (A17); ; |4 F5 ~: k" m' W3 p18. Jumping (A18); ( @0 U3 Q1 J6 `- z2 O+ `7 M8 I19. Playing basketball (A19). 7 F9 Y$ O2 h" @Your team are asked to develop a reasonable mathematical model to solve2 w& N# c/ V5 b! ]5 Q/ Z2 u5 i1 x
the following problems. 4 K. U, N8 a6 t( n: \1. Please design a set of features and an effiffifficient algorithm in order to classify# b5 R3 A6 n" e
the 19 types of human actions from the data of these body-worn sensors.- N# y8 T8 h9 r4 e3 X1 ]3 S4 n
2. Because of the high cost of the data, we need to make the model have 3 ]- b* B2 Z8 Ca good generalization ability with a limited data set. We need to study $ d& T7 e6 p" p. S/ T6 U$ d5 Fand evaluate this problem specififically. Please design a feasible method to9 ?4 r6 X O% d
evaluate the generalization ability of your model.) F$ {$ J- q3 g4 S( k- A0 r) r5 o& `
3. Please study and overcome the overfifitting problem so that your classififi- 9 s8 L P- ?2 S6 W- T, ]* gcation algorithm can be widely used on the problem of people’s action+ V* p, U6 x% a3 \2 {. w7 y3 k
classifification./ `; C% h8 e$ @/ x+ I
The complete data can be downloaded through the following link: , G! K! S, U1 yhttps://caiyun.139.com/m/i?0F5CJUOrpy8oq" \. j; }! [% m
2Appendix: File structure- r8 K" G3 }$ ?; D& ~) S
• 19 activities (a) $ j4 D9 x9 }' o% x( B3 H* B K• 8 subjects (p)3 i b6 ^& @/ E0 h
• 60 segments (s) ' [$ M! }) _, b* x {* i1 i& X• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left0 n- `2 N# L. _" r9 ^2 W& m
leg (LL) % K4 R; O3 b& }' F/ `• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z 4 O7 \0 M6 G, j9 k# {magnetometers)3 a, o5 T* x7 \1 w1 M0 {
Folders a01, a02, ..., a19 contain data recorded from the 19 activities.$ y s3 k: _2 ^" w0 g0 k
For each activity, the subfolders p1, p2, ..., p8 contain data from each of the & H9 ^7 k+ j+ D7 |+ a7 ]* k0 T8 subjects. 4 D4 D: m, G1 @5 {& |" {In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each/ ]! n# E9 D5 e6 g
segment.- l# ^! |& j9 q; `" u$ a/ Z5 M
In each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 & G( D p8 h. V( xHz = 125 rows.) c% _) H5 ]7 | N
Each column contains the 125 samples of data acquired from one of the 8 x& x V( t: x* a& s, Y* {$ _* Ssensors of one of the units over a period of 5 sec. ; Y/ m- I9 T7 CEach row contains data acquired from all of the 45 sensor axes at a particular% v! v- a+ b5 n6 W' ~* b/ R+ h
sampling instant separated by commas.$ l4 ~; l- ?: ?) d+ |( x2 e
Columns 1-45 correspond to:$ G; s/ M/ ~& D/ q* D9 K) O, z
• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, 1 W/ h' w6 g: ~ p5 t) L( u• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, & j& U4 z0 L; w8 Y; f• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, 3 z1 n% X, c% q, N$ p) l4 V7 e" _• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag,, \6 s# d& b+ r6 ^
• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag. ! m5 z* ~ c: A/ s' b9 |6 b% o) gTherefore, ; o/ t0 m$ p, \' C• columns 1-9 correspond to the sensors in unit 1 (T), 5 _% P) q8 T& j& W+ @+ v* w• columns 10-18 correspond to the sensors in unit 2 (RA), ) U8 h- h; H- n• columns 19-27 correspond to the sensors in unit 3 (LA),9 p2 m/ i( s, c
• columns 28-36 correspond to the sensors in unit 4 (RL), 5 j1 @) [9 v9 d4 T Y; g( b• columns 37-45 correspond to the sensors in unit 5 (LL).7 n2 u5 C+ h& p: c- W$ n7 S* K& {
3References , T0 D' ~$ ]/ g[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic) `. \0 {1 w2 x
daily movements using a triaxial accelerometer. Med. Biol. Eng. Comput." q/ f. O. Z _2 M, G
42(5), 679-687, 2004 . m5 s P: U, b( c[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of : ]$ {* ]! G9 elow-complexity fall detection algorithms for body attached accelerometers. 8 C% J1 d; J. @# R; @3 E1 ^Gait Posture 28(2), 285-291, 2008* D2 F4 c4 \# ^; J' \
[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag- [* _4 [( d2 N' x7 ]- F
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.: l; c) ^8 }( |0 H
B. 11(5), 553-562, 2007& W* l2 v$ t& R( ^; o! H
[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con Z% e9 H" S$ A7 j! i2 K+ {9 q4 r: z
trol of a physically simulated character. ACM T. Graphic. 27(5), 2008* f8 _$ w4 ~: A1 U* m7 ~2 A
9 i/ a+ q6 U8 _, u2022 # y2 O5 C1 X. ~: L5 f% R+ u# pCertifificate Authority Cup International Mathematical Contest Modeling 7 A- m4 i+ i2 p7 E3 @http://mcm.tzmcm.cn * `( N6 S+ ?6 [5 V5 }Problem D (ICM)- h3 _7 ^1 O7 b3 B% Y- z, j
Whether Wildlife Trade Should Be Banned for a Long : T# [ \. d" d6 D2 qTime7 s0 ?7 `$ e" b" n; M4 a
Wild-animal markets are the suspected origin of the current outbreak and the - @0 I8 Q6 h) H/ |. U: j2002 SARS outbreak, And eating wild meat is thought to have been a source- Z) D0 _+ r/ h" |
of the Ebola virus in Africa. Chinas top law-making body has permanently( C) j1 G* M5 f* v
tightened rules on trading wildlife in the wake of the coronavirus outbreak, " x+ }2 X3 f% k0 @which is thought to have originated in a wild-animal market in Wuhan. Some 8 h( Q. ] b' G7 F( b4 C# r: ]scientists speculate that the emergency measure will be lifted once the outbreak$ s9 c% p+ b8 \+ o- T6 {& m( y/ y
ends. 8 U# R$ f" c' N E4 w: S$ Y& g, XHow the trade in wildlife products should be regulated in the long term? . N! M. H i6 @% Q, _Some researchers want a total ban on wildlife trade, without exceptions, whereas f3 ^+ q. ~/ [
others say sustainable trade of some animals is possible and benefificial for peo0 f& T, @, A u* }9 i" y; r; l
ple who rely on it for their livelihoods. Banning wild meat consumption could , H6 _$ @; L. \5 \cost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil$ c; e' G/ h! Q9 F; l: D
lion people out of a job, according to estimates from the non-profifit Society of: E/ |7 I" k' g# b# C
Entrepreneurs and Ecology in Beijing. , `" P' o1 H, Z" O& T$ G9 bA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology& b' @: {% ? {& t' ?6 {0 x$ S2 u
in China, chasing the origin of the deadly SARS virus, have fifinally found their9 [' C# [, S4 A0 i
smoking gun in 2017. In a remote cave in Yunnan province, virologists have u. D& J9 m9 A( ]+ {0 p- y0 N, \
identifified a single population of horseshoe bats that harbours virus strains with9 z' |6 L; x6 C
all the genetic building blocks of the one that jumped to humans in 2002, killing1 A& n4 z. n% h$ H" u
almost 800 people around the world. The killer strain could easily have arisen : j4 q) a% k% u7 D/ l/ zfrom such a bat population, the researchers report in PLoS Pathogens on 30; ?2 I% v( _& P2 N. v
November, 2017. Another outstanding question is how a virus from bats in 7 S1 _" g D0 mYunnan could travel to animals and humans around 1,000 kilometres away in6 J6 ~: p0 e( q( ?/ }
Guangdong, without causing any suspected cases in Yunnan itself. Wildlife 9 ~. w; F! c& A* [# N3 x! p: \) Ytrade is the answer. Although wild animals are cooked at high temperature $ G* Z, n4 V9 Y' J1 s9 w* h3 ^) Lwhen eating, some viruses are diffiffifficult to survive, humans may come into contact 6 O( i1 O0 G, Q: ~' R; @! `with animal secretions in the wildlife market. They warn that the ingredients - f+ K2 I Q- w4 ]5 C) qare in place for a similar disease to emerge again.: b0 C7 ]7 b- t8 w5 U
Wildlife trade has many negative effffects, with the most important ones being: 0 }% i0 [. D) k: @9 t; o# r( v1Figure 1: Masked palm civets sold in markets in China were linked to the SARS6 g* }& p9 N2 f7 _
outbreak in 2002.Credit: Matthew Maran/NPL 1 R2 _, f! r `- K• Decline and extinction of populations 4 I$ _4 p9 V/ j, u• Introduction of invasive species$ t0 F" o2 P3 u8 U+ I
• Spread of new diseases to humans ' M" O; `# F, dWe use the CITES trade database as source for my data. This database & e i/ d+ r! K' `! N. ?contains more than 20 million records of trade and is openly accessible. The / v% t. t. ~- d0 w) Sappendix is the data on mammal trade from 1990 to 2021, and the complete0 Z5 R: q' V# j ^5 t9 ]7 s: S% F
database can also be obtained through the following link:, K J9 M6 X2 f
https://caiyun.139.com/m/i?0F5CKACoDDpEJ ' x$ X& S3 |& X) L% b) z. URequirements Your team are asked to build reasonable mathematical mod 5 X( G; }7 X8 |2 H M# g, u5 [( cels, analyze the data, and solve the following problems: 4 { g# E: q3 f& x5 C. ^! j1. Which wildlife groups and species are traded the most (in terms of live / N' d2 q7 ]( q9 o8 l r0 Q3 `animals taken from the wild)?5 _' b, J" E/ b$ z
2. What are the main purposes for trade of these animals? 4 ]- x) i6 e. H3 L& j5 l0 p3. How has the trade changed over the past two decades (2003-2022)? 9 u6 U8 W; d: r4. Whether the wildlife trade is related to the epidemic situation of major: v9 i5 i# O E3 J6 Y+ W
infectious diseases? 8 [0 m* g$ P3 z25. Do you agree with banning on wildlife trade for a long time? Whether it ( p/ z8 `" R+ L9 ?/ J! }1 Fwill have a great impact on the economy and society, and why? + _0 m7 Z; t% Z" h' _9 M6. Write a letter to the relevant departments of the US government to explain ! N- o; I* c( zyour views and policy suggestions.2 {( |( q: ~3 I; z
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