2022小美赛赛题的移动云盘下载地址 , h2 x) U) q T$ S+ J
https://caiyun.139.com/m/i?0F5CJAMhGgSJx3 c/ B/ A0 C! q/ e
9 @" L# c/ m6 s+ @
2022% J7 W! j7 T' @# r$ F1 Q
Certifificate Authority Cup International Mathematical Contest Modeling, U; \ T* m* O' ?5 j
http://mcm.tzmcm.cn 8 F. F% ^) w( c$ l# V: L4 m3 ^Problem A (MCM)" G. \& f6 V4 H, s0 y n8 m0 i$ W: S6 Z
How Pterosaurs Fly% S# T# K* N2 s0 e
Pterosaurs is an extinct clade of flflying reptiles in the order, Pterosauria. They- e7 x( K" N+ q8 s p1 S, d
existed during most of the Mesozoic: from the Late Triassic to the end of6 Q, B0 T2 m# v" t
the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved6 c/ p0 x" O6 o5 K8 T7 M
powered flflight. Their wings were formed by a membrane of skin, muscle, and) ~# b+ F0 \0 K5 v _
other tissues stretching from the ankles to a dramatically lengthened fourth5 ^9 O9 E1 D+ f' _8 W% h9 G1 ]. G* ~# M
fifinger[1]. R* {9 [# ?' f9 a8 e+ w; eThere were two major types of pterosaurs. Basal pterosaurs were smaller ( Y9 j9 p! J3 y. D, Ranimals with fully toothed jaws and long tails usually. Their wide wing mem: b5 a9 _" U9 c+ s) e+ V% p
branes probably included and connected the hind legs. On the ground, they 6 n/ m( @* F! d& S. C8 h; O( p- Hwould have had an awkward sprawling posture, but their joint anatomy and 6 m0 V I) P, K; v0 Z6 E C( ^strong claws would have made them effffective climbers, and they may have lived ' P5 a+ m9 E3 ^( C# c. win trees. Basal pterosaurs were insectivores or predators of small vertebrates.- a0 W3 l; v+ X/ n3 T3 F
Later pterosaurs (pterodactyloids) evolved many sizes, shapes, and lifestyles.- B) o. x& I% X2 I8 L" }8 }3 E: O+ o
Pterodactyloids had narrower wings with free hind limbs, highly reduced tails,* u6 c# k9 ^8 R+ O( [( ^( F
and long necks with large heads. On the ground, pterodactyloids walked well on. T4 |+ r; N" }* x
all four limbs with an upright posture, standing plantigrade on the hind feet and7 H" Z( A( M, X; w/ [, L- D
folding the wing fifinger upward to walk on the three-fifingered “hand”. The fossil ! J; R: q. l( L$ U d7 N: Otrackways show at least some species were able to run and wade or swim[2]. & g/ J3 l. H" cPterosaurs sported coats of hair-like fifilaments known as pycnofifibers, which% H7 T: K% z+ C+ u
covered their bodies and parts of their wings[3]. In life, pterosaurs would have 4 @( D; I U w4 u7 d# Ehad smooth or flfluffffy coats that did not resemble bird feathers. Earlier sug* B8 ]3 x9 O8 O
gestions were that pterosaurs were largely cold-blooded gliding animals, de% c4 Q- f) L7 y" K
riving warmth from the environment like modern lizards, rather than burning 7 v. g# c+ O' i' Qcalories. However, later studies have shown that they may be warm-blooded: D% X* x f: r
(endothermic), active animals. The respiratory system had effiffifficient unidirec. f& J9 q$ j, x5 O( W6 ~; P
tional “flflow-through” breathing using air sacs, which hollowed out their bones 9 I+ K7 D& q/ l, j9 u$ |* jto an extreme extent. Pterosaurs spanned a wide range of adult sizes, from" a$ Y/ w# v/ i7 @
the very small anurognathids to the largest known flflying creatures, including ( x8 n0 ^: e! Q, {$ NQuetzalcoatlus and Hatzegopteryx[4][5], which reached wingspans of at least* N# T) f+ \4 a$ t& f
nine metres. The combination of endothermy, a good oxygen supply and strong1 h( V* ~2 ~+ a: k" v; P+ P
1muscles made pterosaurs powerful and capable flflyers. ! i }& k% o: n$ Z* y: K5 VThe mechanics of pterosaur flflight are not completely understood or modeled 8 B9 q& j$ J+ O* Kat this time. Katsufumi Sato did calculations using modern birds and concluded 7 j+ A5 D* U1 Kthat it was impossible for a pterosaur to stay aloft[6]. In the book Posture, * G" z. y( I/ y6 s* F+ k! n& O4 U* LLocomotion, and Paleoecology of Pterosaurs it is theorized that they were able / N# b; r# F" `# rto flfly due to the oxygen-rich, dense atmosphere of the Late Cretaceous period[7].( I1 g( {4 w8 C, X
However, both Sato and the authors of Posture, Locomotion, and Paleoecology3 b+ h; [" C: T2 f, x8 q8 [' N6 U p' |
of Pterosaurs based their research on the now-outdated theories of pterosaurs # e, A# e) Z) D! i1 Ubeing seabird-like, and the size limit does not apply to terrestrial pterosaurs,) g, _/ b# u' {9 d, t$ d
such as azhdarchids and tapejarids. Furthermore, Darren Naish concluded that : x& S7 a% h$ xatmospheric difffferences between the present and the Mesozoic were not needed5 t# a+ w$ y0 a7 m8 h# t
for the giant size of pterosaurs[8].; k3 P" N% z) x, T- K& s
Another issue that has been diffiffifficult to understand is how they took offff.1 I% m) {6 o; P7 |& b9 \
If pterosaurs were cold-blooded animals, it was unclear how the larger ones% `* u3 S/ @; J
of enormous size, with an ineffiffifficient cold-blooded metabolism, could manage* v. s5 }2 W: @
a bird-like takeoffff strategy, using only the hind limbs to generate thrust for ' p6 U& ]6 {9 F- S7 x5 Pgetting airborne. Later research shows them instead as being warm-blooded6 _, L* r: b8 I$ W+ c4 K$ {1 ^! V
and having powerful flflight muscles, and using the flflight muscles for walking as 6 R8 N5 _4 I I7 G# H. C5 qquadrupeds[9]. Mark Witton of the University of Portsmouth and Mike Habib of$ p! C: i" u1 \8 T
Johns Hopkins University suggested that pterosaurs used a vaulting mechanism. G$ O6 @% y/ ~9 v( ?/ ^
to obtain flflight[10]. The tremendous power of their winged forelimbs would! M9 J3 n. a: n3 B' {
enable them to take offff with ease[9]. Once aloft, pterosaurs could reach speeds3 N9 r2 V/ Q5 C6 H" P( F& f
of up to 120 km/h and travel thousands of kilometres[10]. $ k. k, a/ D0 I* mYour team are asked to develop a reasonable mathematical model of the* b$ L2 F c& y( G" C) x9 v! D
flflight process of at least one large pterosaur based on fossil measurements and " E. G2 P- U( t; uto answer the following questions. * [" y; Q5 t2 E* S/ E7 o1. For your selected pterosaur species, estimate its average speed during nor 4 B" B3 a; t" s8 T+ S- O# l* ~% tmal flflight.3 z1 G. ^/ u/ T" C
2. For your selected pterosaur species, estimate its wing-flflap frequency during ( P' R6 H6 u1 Jnormal flflight.1 O0 s) ]# W* O8 n ?# q
3. Study how large pterosaurs take offff; is it possible for them to take offff like7 K2 X7 p' u, M7 h: j( u4 V" F* T# P
birds on flflat ground or on water? Explain the reasons quantitatively. % M* ]& F) i2 |$ BReferences8 S- E9 c8 t+ R0 K+ D# J, ^
[1] Elgin RA, Hone DW, Frey E (2011). The Extent of the Pterosaur Flight3 W, b: w$ G* V( c' V5 q
Membrane. Acta Palaeontologica Polonica. 56 (1): 99-111.# o3 Y, n' `/ z5 c( R8 `' \7 v$ [* E
2[2] Mark Witton. Terrestrial Locomotion.0 L+ n% N' J; P
https://pterosaur.net/terrestrial locomotion.php ( D3 w4 ~. t$ |1 z+ C+ }[3] Laura Geggel. It’s Offiffifficial: Those Flying Reptiles Called Pterosaurs- a# m% x! Q5 [8 h/ ?
Were Covered in Fluffffy Feathers. https://www.livescience.com/64324- 7 J }7 p8 n2 O7 o0 W( A8 G! {+ Hpterosaurs-had-feathers.html2 b# Z, i# [& k$ Q% F' x {4 d
[4] Wang, X.; Kellner, A.W.A.; Zhou, Z.; Campos, D.A. (2008). Discovery of a+ Y, F0 P# x) f z& `3 ]
rare arboreal forest-dwelling flflying reptile (Pterosauria, Pterodactyloidea)9 z9 \* n0 g$ h. _
from China. Proceedings of the National Academy of Sciences. 105 (6): $ v: K, Z; S6 \1983-87. # i) b' B: a4 u& p/ G5 |. L4 x[5] Buffffetaut E, Grigorescu D, Csiki Z. A new giant pterosaur with a robust Q+ H) y9 l5 e; D, V3 e
skull from the latest cretaceous of Romania. Naturwissenschaften. 89 (4):7 s2 b. ^/ u2 `+ o5 \4 T* |: G
180-84. 7 `2 e( k* [9 [" X[6] Devin Powell. Were pterosaurs too big to flfly?3 Z( m) J% j2 J) b+ ?/ [( B
https://www.newscientist.com/article/mg20026763-800-were-pterosaurs : G8 P$ N4 B/ X" p" _too-big-to-flfly/2 l' i: W f2 [! {/ W3 E0 |
[7] Templin, R. J.; Chatterjee, Sankar. Posture, locomotion, and paleoecology $ }/ b j6 j- Nof pterosaurs. Boulder, Colo: Geological Society of America. p. 60.2 N8 V% P; P1 t/ Z( s6 k
[8] Naish, Darren. Pterosaurs breathed in bird-like fashion and had inflflatable3 g$ Q2 G6 v6 N: L' y( X
air sacs in their wings.5 F4 Q4 ^+ I0 |9 e7 o k
https://scienceblogs.com/tetrapodzoology/2009/02/18/pterosaur ' e) p8 E3 [% h( Mbreathing-air-sacs! R; u& M$ E4 ^) v- y2 ^
[9] Mark Witton. Why pterosaurs weren’t so scary after all.5 k) R2 q5 L( s
https://www.theguardian.com/science/2013/aug/11/pterosaurs-fossils 2 J4 l8 x# P. Fresearch-mark-witton( A5 X3 u# J' }4 h
[10] Jeffff Hecht. Did giant pterosaurs vault aloft like vampire bats?% Y8 r. [2 l: d+ T$ G1 i3 o/ X
https://www.newscientist.com/article/dn19724-did-giant-pterosaurs1 ?4 R% y" I4 B/ s
vault-aloft-like-vampire-bats/9 L: d- X# ?9 N8 I: `
" M; ^+ D" R9 X" N- n p2022 0 F$ K" T# w0 S$ ]Certifificate Authority Cup International Mathematical Contest Modeling. C. B' Y- [3 {! m! D! A& u& q
http://mcm.tzmcm.cn 9 U) T/ L5 b! N0 b! l$ f1 C( qProblem B (MCM) % N1 W7 m6 S( w. `" J9 r3 AThe Genetic Process of Sequences, e1 I9 A2 l2 G& ?* o/ F
Sequence homology is the biological homology between DNA, RNA, or protein 0 i9 l4 O6 Y& b: ~* y# m& Bsequences, defifined in terms of shared ancestry in the evolutionary history of 4 _% B* H) L; b: P9 |life[1]. Homology among DNA, RNA, or proteins is typically inferred from their( T# C1 W) J, U. p
nucleotide or amino acid sequence similarity. Signifificant similarity is strong + y7 T% z$ Z0 @; n4 oevidence that two sequences are related by evolutionary changes from a common* F! \( s8 r" B1 j
ancestral sequence[2]. 8 Q* Z/ L& u$ K3 E& RConsider the genetic process of a RNA sequence, in which mutations in nu 8 F p& g* O. Gcleotide bases occur by chance. For simplicity, we assume the sequence mutation s( ?% V$ E$ `. F5 g( J5 V' Iarise due to the presence of change (transition or transversion), insertion and + I* {; k+ K5 j8 N1 e9 mdeletion of a single base. So we can measure the distance of two sequences by + x# W. N7 T* R- Q) ?6 O( qthe amount of mutation points. Multiple base sequences that are close together 9 P2 b1 D1 b' m. e _6 C/ pcan form a family, and they are considered homologous.5 | |( C* m% E9 m# ?7 d; m
Your team are asked to develop a reasonable mathematical model to com8 H2 B/ x! w% o
plete the following problems. % a4 \$ O( w( @1 H1. Please design an algorithm that quickly measures the distance between V% M; v& ] H( }7 g/ Z. jtwo suffiffifficiently long(> 103 bases) base sequences.) J& k$ O6 ~. Z( ^2 d) G
2. Please evaluate the complexity and accuracy of the algorithm reliably, and 8 I2 v0 T1 K9 w$ Y6 Udesign suitable examples to illustrate it.: E- _8 R3 Y6 w& s7 p) T- R
3. If multiple base sequences in a family have evolved from a common an , B3 ^( V7 {$ ~2 Y1 e9 ccestral sequence, design an effiffifficient algorithm to determine the ancestral% K ?7 ?8 \5 E6 Q T
sequence, and map the genealogical tree.. c) h7 T- M! d
References 1 T' E/ ?1 @3 U) X+ k6 |9 i[1] Koonin EV. “Orthologs, paralogs, and evolutionary genomics”. Annual Re/ ^5 Y% y- Y2 h: w
view of Genetics. 39: 30938, 2005.% p3 X) ]' I: n9 |+ t6 `
[2] Reeck GR, de Han C, Teller DC, Doolittle RF, Fitch WM, Dickerson RE,2 p' L" B7 V: n5 h( ^/ q6 T
et al. “Homology” in proteins and nucleic acids: a terminology muddle and9 w9 S: n# x! e
a way out of it. Cell. 50 (5): 667, 1987., E# f1 a' [2 `% J3 k, ]- [2 b9 w
1 {4 c s' n& t, J* `0 _
2022 $ E! C+ U& H2 @6 J/ R& g0 Z s6 ZCertifificate Authority Cup International Mathematical Contest Modeling: C- ?5 d5 N& l/ x) J4 I5 A
http://mcm.tzmcm.cn + C4 T. k9 k& x# S8 \8 ZProblem C (ICM) 4 O/ n% ?) @( @ TClassify Human Activities 3 C r9 I; `9 U6 i u6 eOne important aspect of human behavior understanding is the recognition and0 Y5 ^ f' N4 V9 j" i3 N
monitoring of daily activities. A wearable activity recognition system can im3 F! M& [) H# |; W
prove the quality of life in many critical areas, such as ambulatory monitor) _7 ^( G6 _& z. V
ing, home-based rehabilitation, and fall detection. Inertial sensor based activ# D2 g$ I7 A# v0 ? L5 u7 w6 m
ity recognition systems are used in monitoring and observation of the elderly " O2 o0 w# s* i8 h8 qremotely by personal alarm systems[1], detection and classifification of falls[2],4 y5 h, l/ E3 F0 m9 S0 E2 R
medical diagnosis and treatment[3], monitoring children remotely at home or in; H1 j$ t0 T( b5 ?7 M0 p2 u
school, rehabilitation and physical therapy , biomechanics research, ergonomics, ! @9 \9 c! b7 ^1 T/ N& A: M. xsports science, ballet and dance, animation, fifilm making, TV, live entertain* J3 ?' M6 L9 i4 S8 l: u0 a) Z
ment, virtual reality, and computer games[4]. We try to use miniature inertial 3 x! h' y# J6 |+ B: X; Usensors and magnetometers positioned on difffferent parts of the body to classify 2 g4 b/ E0 P2 r. [: e8 ]human activities, the following data were obtained. 6 X! j2 L; s- z' ?Each of the 19 activities is performed by eight subjects (4 female, 4 male,( i1 o3 [# H6 i0 o4 u3 I/ a
between the ages 20 and 30) for 5 minutes. Total signal duration is 5 minutes ; n) Z& ~( f, F8 q* ufor each activity of each subject. The subjects are asked to perform the activ 6 Y5 ]0 B" x+ \" [8 X( J" C1 j1 Yities in their own style and were not restricted on how the activities should be ' F' l' C1 u+ T% `) bperformed. For this reason, there are inter-subject variations in the speeds and ; y. E* c6 J7 a2 ] Aamplitudes of some activities. * z, G8 }' A0 @9 `1 Y- b9 oSensor units are calibrated to acquire data at 25 Hz sampling frequency. n$ I* m8 _- _0 [
The 5-min signals are divided into 5-sec segments so that 480(= 60 × 8) signal - Q3 J+ B2 L( T$ ]3 Fsegments are obtained for each activity. 3 \4 x$ }! V }; X$ c* @: {& EThe 19 activities are: : _. Q/ m g: h, d1. Sitting (A1); * a/ ]- p3 r! A5 H3 Z2. Standing (A2);# Y% Q# c$ n8 {
3. Lying on back (A3); 7 r$ Z& L( _+ b/ u& Q# a4. Lying on right side (A4); , v5 }" B7 d. ~" u, N5. Ascending stairs (A5); % J4 z6 o/ j; ?5 H) f16. Descending stairs (A6); 9 c) \- S- i) A f9 c& l5 p7. Standing in an elevator still (A7);' m1 Y% g$ O0 {7 i* m; B% o9 k+ z
8. Moving around in an elevator (A8); L) p1 o. i: N5 B$ _8 ~5 x9. Walking in a parking lot (A9);, W; ]' g3 ~) [# B! A8 C
10. Walking on a treadmill with a speed of 4 km/h in flflat position and 15 deg 2 j/ e% |$ y, ]inclined positions (A10);+ U( w; l. o+ _
11. Walking on a treadmill with a speed of 4 km/h in 15 deg inclined positions m* B0 n9 R) @1 s8 A9 x
(A11);) ~- ]8 D0 i0 I* p
12. Running on a treadmill with a speed of 8 km/h (A12); 9 `' i0 P( c- x* K' h13. Exercising on a stepper (A13); / F+ J4 e5 j- Q14. Exercising on a cross trainer (A14); ( H- x2 h1 w6 l3 F15. Cycling on an exercise bike in horizontal position (A15); . h- h/ A# u7 a. B {7 l16. Cycling on an exercise bike in vertical position (A16); " u2 a2 W' \2 ~' _17. Rowing (A17); ( I# w( D+ v" v3 _18. Jumping (A18);8 ?# G& b0 i6 U: v- D
19. Playing basketball (A19).; V3 V( q" P; V+ U- }3 Z# Z
Your team are asked to develop a reasonable mathematical model to solve5 h& ?) _" w) h' ~* ?# }# A5 @
the following problems.- O! X$ {" f/ t/ U( Z
1. Please design a set of features and an effiffifficient algorithm in order to classify ; k& i X5 |; Bthe 19 types of human actions from the data of these body-worn sensors. ; K( k+ O6 j3 T. |* H2. Because of the high cost of the data, we need to make the model have. w( a- _/ I0 {% h! ~) }& x9 v
a good generalization ability with a limited data set. We need to study+ a# p6 D* j' r' `
and evaluate this problem specififically. Please design a feasible method to & N9 j: v8 W9 d- u" L1 Gevaluate the generalization ability of your model.% S) t* A$ c4 g* f6 h
3. Please study and overcome the overfifitting problem so that your classififi-. A7 S9 U. T# g$ M6 j4 x& R7 \1 U
cation algorithm can be widely used on the problem of people’s action & U- |3 G& g( O! ]7 |6 H. a$ Tclassifification. 3 C) c( W# h" K2 E/ L" `, g3 S) X& @8 A; PThe complete data can be downloaded through the following link: ' y# x& k8 j- y9 R9 h6 _: hhttps://caiyun.139.com/m/i?0F5CJUOrpy8oq8 q. M* W% B$ C: ]6 V
2Appendix: File structure& U0 A2 ]; q, ~" F I" t
• 19 activities (a) + d" r! `$ S w ]3 M. ]& B• 8 subjects (p) ~2 g, M5 B# J• 60 segments (s); D! R/ e4 R6 k/ U' _$ H' n8 x
• 5 units on torso (T), right arm (RA), left arm (LA), right leg (RL), left5 }5 t/ V% ^: x6 ?& I/ u
leg (LL)3 y9 d' I8 i r
• 9 sensors on each unit (x, y, z accelerometers, x, y, z gyroscopes, x, y, z: \; A$ J& T) i% B
magnetometers) # \$ p) q- G1 G KFolders a01, a02, ..., a19 contain data recorded from the 19 activities. $ h2 M& ^. @+ }) E8 l! UFor each activity, the subfolders p1, p2, ..., p8 contain data from each of the1 m: K9 d( {: j; y; w
8 subjects., a' a$ _' P: l, q
In each subfolder, there are 60 text fifiles s01, s02, ..., s60, one for each" [4 L2 A( d) G8 b8 J$ e6 g Y7 U
segment. . j: }( b8 n+ XIn each text fifile, there are 5 units × 9 sensors = 45 columns and 5 sec × 25 % \" [3 J+ L+ y5 P% @. s3 [Hz = 125 rows. 1 V8 O- I8 ^/ P" Y; N, mEach column contains the 125 samples of data acquired from one of the ) v- \8 B4 s! w: b9 wsensors of one of the units over a period of 5 sec., X& r# Y! R r
Each row contains data acquired from all of the 45 sensor axes at a particular6 L& ^3 o4 y- M0 i3 B5 [, P7 z1 n4 b
sampling instant separated by commas. , a! _( C& q6 ]( U8 L$ @Columns 1-45 correspond to: + o- Z# T9 G" I+ }8 `. f• T_xacc, T_yacc, T_zacc, T_xgyro, ..., T_ymag, T_zmag, 7 k# p% z5 K2 c1 b& s% u( k• RA_xacc, RA_yacc, RA_zacc, RA_xgyro, ..., RA_ymag, RA_zmag, * g, Y$ ] J+ }• LA_xacc, LA_yacc, LA_zacc, LA_xgyro, ..., LA_ymag, LA_zmag, - L7 ?, p/ o4 `, L* H5 _2 q; m• RL_xacc, RL_yacc, RL_zacc, RL_xgyro, ..., RL_ymag, RL_zmag, 3 O3 p8 h+ D s4 g, d. x8 U# j0 F• LL_xacc, LL_yacc, LL_zacc, LL_xgyro, ..., LL_ymag, LL_zmag.9 X1 h( \1 e+ z! a6 r1 H
Therefore, * L% l& ^! `/ M5 n _3 X6 q/ m1 t• columns 1-9 correspond to the sensors in unit 1 (T), 0 f+ L* ]. f1 s& p( a6 O8 Q• columns 10-18 correspond to the sensors in unit 2 (RA),- E, _$ I( I6 v6 G, {
• columns 19-27 correspond to the sensors in unit 3 (LA),2 K e. P6 e$ m; `( S
• columns 28-36 correspond to the sensors in unit 4 (RL), & E6 E! V, s% \; S* I' l- q• columns 37-45 correspond to the sensors in unit 5 (LL).1 t) y, f% j) O3 r1 B
3References' L) j9 j1 m* N6 v
[1] Mathie M.J., Celler B.G., Lovell N.H., Coster A.C.F. Classifification of basic " B0 V* j! b( j2 e% T+ fdaily movements using a triaxial accelerometer. Med. Biol. Eng. Comput. ( m- Q8 t% u( i9 m* M1 ?2 u42(5), 679-687, 2004 4 i$ r1 F1 {( {4 U: u S[2] Kangas M., Konttila A., Lindgren P., Winblad I., Ja¨msa¨ T. Comparison of y! _' m" k, w' A' A
low-complexity fall detection algorithms for body attached accelerometers.- _ H$ f/ q# n; z# j
Gait Posture 28(2), 285-291, 2008 6 e. v! Z. l9 K[3] Wu W.H., Bui A.A.T., Batalin M.A., Liu D., Kaiser W.J. Incremental diag7 k" V/ H. W& `5 @, x; ^, c
nosis method for intelligent wearable sensor system. IEEE T. Inf. Technol.* f, X- R9 h$ _
B. 11(5), 553-562, 2007 7 A# m+ S$ ], m. Z[4] Shiratori T., Hodgins J.K. Accelerometer-based user interfaces for the con8 F; D5 q; V' n* H3 Z$ q" Z2 Z
trol of a physically simulated character. ACM T. Graphic. 27(5), 20087 A) \0 g1 d/ _9 m4 ?
% }5 \, k0 j9 q* K' V2022 7 R6 F4 z" n, yCertifificate Authority Cup International Mathematical Contest Modeling " ]& m6 D$ T% H whttp://mcm.tzmcm.cn# ~, m3 S6 l% c8 S* V- Y% D# K0 R
Problem D (ICM)% V8 B% \' v3 ?/ s
Whether Wildlife Trade Should Be Banned for a Long& b1 A1 v, U6 M' K4 K9 R
Time4 v: W5 V4 x9 y
Wild-animal markets are the suspected origin of the current outbreak and the8 S4 B y& n% }/ e/ G
2002 SARS outbreak, And eating wild meat is thought to have been a source, C/ c7 X5 C O- T; w8 M: w. j
of the Ebola virus in Africa. Chinas top law-making body has permanently# Y; b( s* G/ }, q; ?7 E
tightened rules on trading wildlife in the wake of the coronavirus outbreak, 2 U# D% B1 x2 n, n) H8 |7 Y- bwhich is thought to have originated in a wild-animal market in Wuhan. Some; J6 h9 b- S' s$ \
scientists speculate that the emergency measure will be lifted once the outbreak ; V% O! |( p; G, V! U L# s" Gends. 6 T6 K0 M9 H4 h' d- U, kHow the trade in wildlife products should be regulated in the long term?7 q7 c z3 _* M, K5 ?( }
Some researchers want a total ban on wildlife trade, without exceptions, whereas7 B% H1 d" c4 `5 E
others say sustainable trade of some animals is possible and benefificial for peo! D! C0 k+ E. Q
ple who rely on it for their livelihoods. Banning wild meat consumption could $ w. `! c M) n }4 A; Ocost the Chinese economy 50 billion yuan (US $ 7.1 billion) and put one mil " o, w1 N0 f9 Zlion people out of a job, according to estimates from the non-profifit Society of 7 K& ]6 I3 Y9 [2 H! Z8 ?3 ~/ \5 s$ EEntrepreneurs and Ecology in Beijing. + @+ z6 @% a# g' oA team led by Shi Zheng-Li and Cui Jie of the Wuhan Institute of Virology5 M2 e- P A1 i5 Z7 E
in China, chasing the origin of the deadly SARS virus, have fifinally found their! A2 {0 T- I) b2 G* ~' k$ C
smoking gun in 2017. In a remote cave in Yunnan province, virologists have 3 u5 A6 P* [0 m, v2 Pidentifified a single population of horseshoe bats that harbours virus strains with t" P2 c' `1 D7 I% A* Z7 C
all the genetic building blocks of the one that jumped to humans in 2002, killing $ S( n8 T7 @+ D( V8 n2 x1 g& ?almost 800 people around the world. The killer strain could easily have arisen 7 O9 H7 r9 B" V) tfrom such a bat population, the researchers report in PLoS Pathogens on 30 6 h5 Y; X0 x9 i3 N9 P0 YNovember, 2017. Another outstanding question is how a virus from bats in" J- j! S1 o* {( U, ?) A
Yunnan could travel to animals and humans around 1,000 kilometres away in $ b0 v% [3 A8 I6 c* e( uGuangdong, without causing any suspected cases in Yunnan itself. Wildlife 9 V1 G% v1 Q: @0 ]; \trade is the answer. Although wild animals are cooked at high temperature0 ~9 W5 u+ f( P) w$ C$ u- |
when eating, some viruses are diffiffifficult to survive, humans may come into contact$ P7 r3 V) D3 a q
with animal secretions in the wildlife market. They warn that the ingredients $ r) a+ ^- r8 c2 vare in place for a similar disease to emerge again. # W9 m7 G# {8 t& S+ p' ^3 ]Wildlife trade has many negative effffects, with the most important ones being:' Y* j6 C! a9 }$ p3 A- E+ L
1Figure 1: Masked palm civets sold in markets in China were linked to the SARS6 l2 ?* K1 u& \& J; q
outbreak in 2002.Credit: Matthew Maran/NPL 8 e4 V( F3 n/ n9 W• Decline and extinction of populations / u7 z, f# U# P" U* c' q• Introduction of invasive species5 [2 p- U5 y( |, p
• Spread of new diseases to humans/ M" M1 W, N- }9 `" Z/ j9 n
We use the CITES trade database as source for my data. This database n1 Y' P# b0 R. D
contains more than 20 million records of trade and is openly accessible. The : S: |+ s' d! W" ]6 {7 o! mappendix is the data on mammal trade from 1990 to 2021, and the complete . O. ~ \4 F% P F9 qdatabase can also be obtained through the following link:9 D/ T5 w# e" A3 e- v
https://caiyun.139.com/m/i?0F5CKACoDDpEJ , D$ |( j1 i' m) V. w8 E5 WRequirements Your team are asked to build reasonable mathematical mod " D p8 k1 x- V/ Xels, analyze the data, and solve the following problems:+ K- |- j' V( b# N. m
1. Which wildlife groups and species are traded the most (in terms of live. v7 m( x9 ]3 C6 z- U& m6 u& @
animals taken from the wild)? % S3 c0 ^% u9 V5 b; Z2. What are the main purposes for trade of these animals? 8 N' j: h; s6 Y0 A+ J( p& X3. How has the trade changed over the past two decades (2003-2022)?1 T* n9 I) O4 S! e: k! H3 }
4. Whether the wildlife trade is related to the epidemic situation of major % c1 a& ~: n, @ @+ ~4 Rinfectious diseases? * T5 O) p& n# b5 D2 z25. Do you agree with banning on wildlife trade for a long time? Whether it 8 Z) i! x2 O5 R1 d3 l' \5 Mwill have a great impact on the economy and society, and why?# E+ ?7 H. L% G6 Q( Z1 w" I
6. Write a letter to the relevant departments of the US government to explain % E2 x- v e0 N! lyour views and policy suggestions. $ h& U, K# y6 L" i; Y7 U 4 b( d( _+ V: z- w# [% F+ e0 p/ L$ I2 h, ?" v
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