! "#$%&$'(%)*+')',-"&$ "#-%.//(%)((% )-"&$* 0!.1#&2 /' 3.-#(4"$"&5##&2&56)/ , * +7$89(%).:##6#(%);* <=4>?8;!6#!(@'89(% )&5 ,%(A?6B.&2*C?#6#= BD(;;#;!;E)F($G.2 -* H8$!(%)#I #&2# GF#=B4*J'B!6G!; #&K;(6#1E';('3 *+B!(( ('! #=/"#=/L)&5M86) &2##%"#4* N##6'!OP0(6)!QR9BGF "#GF***************************************H/2BA&$89&$S T !I.46##)%46 /@ 1(F##&5U%.I*V76W%X? 8'F%461(FI?8'')U%.F&5 #!;* YG#;467#)%46 /@ 1(F##U%!(.I** Trang 1 ! " # Z*Z* $ # %&'( NB [ [ \ ] [ ] GF ] 6 ^ & ^ GF ^ B \ ( [ ] ] "& ] " ^ \ GF6 ] " ] * <&; ^ " \ ] ( ^ ] ((; \ ( ] ] "& ] _( [ "& ] ; \ M ] &; ^ `" ^ \ \ GF& ^ " ] ^ M \ ( ] "& ] _ \ a \ ` \ & b GFB \ ( ] ] 6 \ " ^ GF& ^ " ] *C \ \ \ M"&; ] _ ] M` [ \ \ GF6&; ] 6B [ ^ B ] 8 \ _B ] M` M ^ \ \ ] "B \ (" ^ \ \ GF& ^ 6* C&; ^ " \ & b ( [ B \ & ^ GF ^ ^ ( [ B \ \ GF& ^ " ] F 6 \ ] [ a ^ *+M [ ] & \ (( [ [ \ ] F& \ a \ ; ] ( ^ & ^ GF&; \ [ ] ] ] &; ^ &; \ M \ ( [ \ (* Trang 2 + \ ; \ a \ ] & \ M& ^ GF ^ 6" ^ B ] \ (& ^ ] (( ^ \ " \ (GF* ( c!(7)/6)/.>d //#'F6B4.&2"%*C#!(3 ?>=2"#GF2 >GF_(6`* N$%6e!('3I' 6)/#=/>GF6)2 6#&5M86)M&5/"9* N)!(%I"#!.!(I'( %6B48K f+'/6)A$%&25(6)* f+'!(=% %GF&25(g"#( -&5"9("$U2% %GF* fc-/B 89-/.(( !(6Uh#('F(&=% %GF7O.)%!&5"!"9(* fN)D#) $&2/"/.&2"%K-! 8"9-((.&2"%"#XS-&5"9($ % %GF"#"$*N) 6B4#6!('"i(B /5"9 _5"95"9e5"9j"9`* fJS/('/-6)A$%&25(6)* fN !( F(B% %GF(F6Bi8QO ##"&5 %($&2/* f<'!&59G(#(A2&2"%-( (*C8k6)I6)/* Trang 3 f+;((%!K9.%I("#8QO"98% 8=;()-F6)/6. %GFGe M"&5I!("# l/M.#!M.; (*<(!/8=;(*J';(( 'M6!* f?&5T"!?"9B #-(3)$"9(B %GFKA"#!S/(('j86l*0-%6B "%GF-((* +'!88%?(46#%(#l!8QO* f+'M(A2#* fJm"i(%(T &n#8Q?* +' TBA&57)%%!(K 4(* 02(* o@&2(* p9("9(B* N6"#/TB)%%!(* 4#"$I!(#* <(B&2 ,I"9(q q rstl%"9 %I(*J'')"9(8k ,$"9%*V% M("9(=% %GF3(O/#M % .% %GF$&2* 49-(&5G%FA8K Pmax g. J ϕ = δ _Z*Z` 0'Kδ"#!8&=.%"&56. (U2&/ .(G1? %GF$&2* +A_u*Z`6K(-&5(O/# "&5# /.#)M4(_A"#M! Trang 4 (`I4!8 δ *+d-&25(((&2"%B i"65()%/;"#!X!6"9"- X&5"9 %"&56./;#.6"#. %#*<' % δ 8kG% ' δ e;v qG 8kM"B* v qG (O/#!8 % ϕ ?"($&2*%!8 %"$ max 0,7 0,8ϕ = ÷ B&29*C 1 δ = #&2w Zxy8 u I49-(B&29,' )-8K 2 P max J 7,0 8,0[m / s ] = ÷ * 0%I(4T-(4X; v qG u÷z"4*q(TG6?I !6 )#T{÷Zxtl8"4(* 02(W"#/%TB%%!(W &"&5%I(*02(#XA"#!(# * +A_u*Z`&5)!&$-(&8K dv g. dt ϕ = δ _Z*u` dt .dv g. δ ⇒ = ϕ _Z*z` VG%2(4("&5$->2 )A$ i4( Z $2) u =%I(* +AG%2(&8K ( ) 1 2 v P 1 2 v t .dv . v v g. g. δ δ = = − ϕ ϕ ∫ _Z*|` C(>dI u wx'2(X q &5&8K Trang 5 P min 1 t .v g. δ = ϕ _Z*{` +A_u*{`62(X q (O/# "&5GF#(O/# i4( Z (O/#!8 &=."&56 δ #(O/#!8 % ϕ ? %GF$ &2*N)2(&2"%Bi"65((* !"# !"#$%&' o@&2(H q "#TB)%%!(W& "&5%I(.*H$%TB%ITB#6 9#91("%GFGQ"}(B&2*+TB#6 &2&5&#%#"!M:.'~F% i4(&;A*o@&2(#XI"&5( #* +A@&2(&5G%B;8= )A_Z*u` ,% . )A_Z*u`$/"&5(HK dv g. .dS .dS dt ϕ = δ dS g. .dv v.dv .dS dt ϕ ⇒ = = δ _Z*•` dS .v.dv g. δ ⇒ = ϕ _Z*€` %@&2(H q &5G% ,%(/"&5HF )A$->2)A$ i4( Z $2 ) u =%I(*+AG%@&2(& 8K ( ) 1 2 v 2 2 P 1 2 v S .v.dv . v v g. 2.g. δ δ = = − ϕ ϕ ∫ _Z*s` C(>dI u wx'2(XH q &5 &8K Trang 6 2 P min 1 S .v 2.g. δ = ϕ _Z*r` +A_Z*r`6,@&2(X(O/ #6)/."1 i4( Z (O/#!8&= ."&56 δ #(O/#!8 % ϕ ? %GF$&2*N) @&2(4!8 δ B&2"%4i"65(U$(* +%A_Z*Z`_Z*{`_Z*r`"}6(O/#"&5# /.*C& AB(O/#!8 % ϕ #!8 ϕ "-(O/#.*<M"BI ϕ '( 48k32(#@&2(8kM"B*•I69 !@A&5,@&2(.GFGF#GF% %7 i4(=7/ Z *NUBIZ*Z !'K NUBIZ*Z{@6, i4( Z #I @ &2 ( H q # "$ I @ &2 ( (O / # I(&;. Z U2 ! 8 % ϕ # I @ &2(H q #* cIZ*Z{*NUT896l@ &2(F i4( Z #F!8 %ϕ !"#(' +%A_Z*Z`_Z*|`_Z*s`G%42(# @&2("}6!"}&=$% @&5*<'%(8e!&5&-%9- 6-2) i4(#2(A."%GF&5)* 02(9(&5>( i4'!#( Trang 7 >&2"%&5!)(*J' q #H q 8k"$;8$% %F%A_Z*{`_Z*r`* N) G% @ &2 (94BA% I ( % U 9 !)!!?"9 (q q 8= %GF_ F(V q `$2* NU #6 &5 "# U (_IZ*Z•`* cIZ*Z•*U( U(&5 ,9!#U(')( #6&5 .%I(* 0BU-/&5"#2)&2"%(%!&$-= (&$#A&5,4((GF*02%-% I(9&5G%O)U'K • Z K2(G-.&2"%A"#>"16&5&$- "1%O# #-((*02#6(O/#I/. &2"%*02 Z &2,$- Z wxz÷xs8* • u K2%O.!((i(O#I9 !A"#2>"1&2"%%O# #-(( %(e(8%#(*02#6(O/# S/($(e u wxu÷x|8* • z K2M"9(#M4*02#6W(O /#S/($(e z wx{÷Z8* • | K2(##$"9(9-q qG #$4 9-v qG *02#6&5G%FA_Z*Z`*02 #6"9(#4'%l* • { K2(8GF>"9(4x*N$( e u wZ{÷u8* <@>##I2( { &=@&2 (X*C&62(9l/)>"1'!( (>d8k"#K Trang 8 q w Z ‚ u ‚ z ‚ | _Z*Zx` 0>U(6=2 Z ‚ u "9(#4 ,*p9(# i4M"B>2)ƒ"#)=4. 2 z *+2 z "9(#4-%9-#? l82 | *+2 | 4#"9( i 4*c2 { "9( ,*42 | &5"#4l* 06BU(B6@&5;'3U("6 >9!'-&258'(* C)2(G-.&2"%#2%O.S /(I@&2(9&5G%&8K H q wH Z ‚H u ‚H z ‚H | _Z*ZZ` 0'K H Z ‚H u w Z *_ Z ‚ u ` _Z*Zu` 2 3 3 1 3 P max t S v .t J . 6 = − _Z*Zz` o@&2GF-62 | &5G%>! , ?"9(8$/M.GF2 | K 2 P max 4 4 G P .S .v 2.g = _Z*Z|` 0'K ) )* "#"9(B-&2H | „C… + , "# 4.B-&2H | „y8… 3 4 1 Pmax t v v J . 2 = − 0>''AG%H | &8K 2 2 1 1 3 P max 3 4 Pmax v v .t J .t S 2.J 2 8 = − + _Z*Z{` 0l@&2(.8k"#K Trang 9 2 2 3 1 P max 3 P 1 1 2 P max t v J .t S v . t t 2 2.J 24 = + + + − ÷ _Z*Z•` <(($-@A %GF%4IK v qG w*ϕ <'@&2(&25(((8k"#K 2 2 3 1 3 P 1 1 2 t v g. .t S v . t t 2 2.g. 24 ϕ = + + + − ÷ ϕ _Z*Z€` 0%I8QO9%( 3#T 18k"#@&2("$;#(4 Zx÷Z{t8$(3$#T1* -(+.$( †TB@&5GFGe=B*p9(#"9( BW"#TB)%%!(*06BTB#6T&57 "5Q(B !Q* p9(8=% %GF&5G%FAK P P K M P r = _Z*Zs` 0'K / ) "#F(.%;(„C*… 0 "# %%. %GF„… p9(B P γ "#"9(B/;"&5# /.* p9(B&5G%FA_Z*Zs`K P P P G γ = _Z*Zr` p9(B-9-"9(-9-K P max P max P G. G G ϕ γ = = = ϕ _Z*ux` +A_u*Zr`6"9(B9-'% ,!8 %*C& 6"}6"9(B9-')-&5%€x÷sxtB Trang 10