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【单选题】
Mathematica软件中,Show命令的功能是( )。
A.
显示图形以及图形的组合
B.
显示软件的特性
C.
显示软件的版本
D.
其余说法都不对
拍照语音搜题，微信中搜索"皮皮学"使用
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参考解析：
知识点：
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皮皮学刷刷变学霸
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【判断题】本案例中,在被告向原告签署了三份电放提单,提单上记载货物运输方式为CFS/CFS,另,提单中还载明了拼箱服务费。由此,被告只能以无船承运人的身份对装拆箱时的过错承担责任。
A.
正确
B.
错误
查看完整题目与答案
【简答题】Fill in the blanks by selecting suitable words from the word bank. You may not use any of the words more than once. A. hinge B. vary C. much D. particulates E. locating F. s...
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【单选题】Write MATLAB codes to implement DSSS system sinmulation, The system is a 2-user system with a 2-path frequency selective fadingchannel for each user, The power for each path is half the total transmit...
A.
N_Trials=300; N_number=100; N_snr=10; N_users=2; N_path=2; Delay=1; Q=16; N_samples=N_number*Q; E_M=0; for trials=1:N_Trials trials noise=randn(N_users.*N_path,Q*N_number)+j.*randn(N_users*N_path,Q*N_number); s10=round(rand(N_users,N_number)); ss_user=s10*2-1;  % without consideration of delayed path pn01=round(rand(N_users,Q)); pn=(pn01.*2-1)./sqrt(Q); S_spread=[]; for user=1:N_users s=kron(ss_user(user,:), pn(user,:)); S_spread=[S_spread; s]; end S_multipath=[]; for user=1:N_users s_user=S_spread(user,:); Suser_delayed=[zeros(1,Delay), s_user(1,1:(N_samples-Delay))]; S_multipath=[S_multipath; [s_user;Suser_delayed]]; end %___________the following is to generate Rayleigh fading coefficients N=N_users.*N_path; fad_c=fading(8,0.005,N_samples, N); fad=fad_c.'; % only use the amplitude; %phase is not used, which is equivalent to have an ideal phase %compensation by using channel equalization S_spread=S_multipath.*fad; %S_spread is the signal matrix of size users x N_number sgma=1; Error_M=[ ]; for snr_db=0:1:N_snr snr=10.^(snr_db./10)/2;  %Evaluate the SNR from SNR in dB N0=2*sgma.^2; Eb=snr.*N0; yy=sqrt(Eb./2)*S_spread+noise;      %received spread signals in the baseband Error_v_user=[]; for user=1:N_users y_path1=yy((user-1).*N_path+1, :); y_path_temp=yy((user-1).*N_path+2, :); y_path2=[y_path_temp(1,Delay+1:N_samples), zeros(1,Delay)]; Y_M_path1=[ ]; Y_M_path2=[]; for k=1:N_number ym1=y_path1(1,(k-1)*Q+1:k*Q); ym2=y_path2(1,(k-1)*Q+1:k*Q); Y_M_path1=[Y_M_path1;ym1]; Y_M_path2=[Y_M_path2;ym2]; end % Y_M is a matrix of size N_number x Q, each row correspinding to a % BPSK symbol ys=Y_M_path1*pn(user,:).'+Y_M_path2*pn(user,:).'; %despreading for a user y=ys.'; y_real=real(y); s_e=sign(y_real); s_e10=(s_e+1)./2; Error_snr=sum(abs(s10(user,:)-s_e10)); Error_v_user=[Error_v_user;Error_snr./N_number]; %A BER collumn vector for all the users and for each snr end  %for user Error_M=[Error_M,Error_v_user]; %BER matrix for all users and for all the SNRs end  % end for snr E_M=E_M+Error_M ; end   % end for trials BER=E_M./N_Trials; BER_T=[ ]; for snr_db=0:1:N_snr snr=10.^(snr_db./10); temp=sqrt(snr./(1+snr)); BER_THEROY=(1-temp)/2; BER_T=[BER_T,BER_THEROY]; end i=0:1:N_snr; semilogy(i,BER(1,:),'-r',i,BER(2,:),'ob',i,BER_T ,'*g'); xlabel('E_b/N_0(dB)') ylabel('BER') legend('User1 RAKE','User2 RAKE', 'Theoretical flat fading');
B.
no need
C.
no need
D.
no need
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【单选题】听力原文：Members of the I.M.F. approved reform. measures that aim to increase the voting power of countries with growing economies. As a first step, they agreed to increases in the voting rights for China...
A.
正确
B.
错误
查看完整题目与答案
【简答题】(A)daydream (B)disagreement (C)factually (D)if (E)inevitable (F)inseparable (G)lays (H) (I)perspective (J)resides (K)that (L)thinking (M)thoughtfully (N)ultimately (O)wake To some thinkers, it...
查看完整题目与答案
【判断题】仓库配送服务就是对客户商品物流的保证，要符合客户所期望的质量，在客户希望的时间内配送商品，不惜成本也要满足客户需求。
A.
正确
B.
错误
查看完整题目与答案
【判断题】擦洗附件及整机外观，检查各传动部分、润滑系统、冷却系统确认无误后，先手动后机动试车，使机床正常运转。
A.
正确
B.
错误
查看完整题目与答案
【单选题】What view did the three Milesian philosophers share?
A.
They all believed that the mythology had a basis in fact.
B.
They introduced a scientific approach to explaining nature.
C.
They thought that water was the original element.
D.
They all agreed with the teachings of Socrates.
查看完整题目与答案
【单选题】为了防止麻醉废气污染对手术室工作人员的健康造成不良影响,下列关于麻醉废气污染防护措施的叙述不正确的是
A.
改善手术室的通风条件，建立完备的排放系统
B.
实施手术室工作岗位的轮换制度
C.
女性孕期适当减少手术间工作
D.
提高手术室的工作效率
E.
选用密闭性能好的麻醉机
查看完整题目与答案
【多选题】照明开关箱中电器配置的组合,主要有
A.
刀开关、熔断器、漏电保护器
B.
刀开关、断路器、漏电保护器
C.
刀开关、漏电断路器
D.
断路器、漏电保护器
查看完整题目与答案
相关题目：
【判断题】本案例中,在被告向原告签署了三份电放提单,提单上记载货物运输方式为CFS/CFS,另,提单中还载明了拼箱服务费。由此,被告只能以无船承运人的身份对装拆箱时的过错承担责任。
A.
正确
B.
错误
查看完整题目与答案
【简答题】Fill in the blanks by selecting suitable words from the word bank. You may not use any of the words more than once. A. hinge B. vary C. much D. particulates E. locating F. s...
查看完整题目与答案
【单选题】Write MATLAB codes to implement DSSS system sinmulation, The system is a 2-user system with a 2-path frequency selective fadingchannel for each user, The power for each path is half the total transmit...
A.
N_Trials=300; N_number=100; N_snr=10; N_users=2; N_path=2; Delay=1; Q=16; N_samples=N_number*Q; E_M=0; for trials=1:N_Trials trials noise=randn(N_users.*N_path,Q*N_number)+j.*randn(N_users*N_path,Q*N_number); s10=round(rand(N_users,N_number)); ss_user=s10*2-1;  % without consideration of delayed path pn01=round(rand(N_users,Q)); pn=(pn01.*2-1)./sqrt(Q); S_spread=[]; for user=1:N_users s=kron(ss_user(user,:), pn(user,:)); S_spread=[S_spread; s]; end S_multipath=[]; for user=1:N_users s_user=S_spread(user,:); Suser_delayed=[zeros(1,Delay), s_user(1,1:(N_samples-Delay))]; S_multipath=[S_multipath; [s_user;Suser_delayed]]; end %___________the following is to generate Rayleigh fading coefficients N=N_users.*N_path; fad_c=fading(8,0.005,N_samples, N); fad=fad_c.'; % only use the amplitude; %phase is not used, which is equivalent to have an ideal phase %compensation by using channel equalization S_spread=S_multipath.*fad; %S_spread is the signal matrix of size users x N_number sgma=1; Error_M=[ ]; for snr_db=0:1:N_snr snr=10.^(snr_db./10)/2;  %Evaluate the SNR from SNR in dB N0=2*sgma.^2; Eb=snr.*N0; yy=sqrt(Eb./2)*S_spread+noise;      %received spread signals in the baseband Error_v_user=[]; for user=1:N_users y_path1=yy((user-1).*N_path+1, :); y_path_temp=yy((user-1).*N_path+2, :); y_path2=[y_path_temp(1,Delay+1:N_samples), zeros(1,Delay)]; Y_M_path1=[ ]; Y_M_path2=[]; for k=1:N_number ym1=y_path1(1,(k-1)*Q+1:k*Q); ym2=y_path2(1,(k-1)*Q+1:k*Q); Y_M_path1=[Y_M_path1;ym1]; Y_M_path2=[Y_M_path2;ym2]; end % Y_M is a matrix of size N_number x Q, each row correspinding to a % BPSK symbol ys=Y_M_path1*pn(user,:).'+Y_M_path2*pn(user,:).'; %despreading for a user y=ys.'; y_real=real(y); s_e=sign(y_real); s_e10=(s_e+1)./2; Error_snr=sum(abs(s10(user,:)-s_e10)); Error_v_user=[Error_v_user;Error_snr./N_number]; %A BER collumn vector for all the users and for each snr end  %for user Error_M=[Error_M,Error_v_user]; %BER matrix for all users and for all the SNRs end  % end for snr E_M=E_M+Error_M ; end   % end for trials BER=E_M./N_Trials; BER_T=[ ]; for snr_db=0:1:N_snr snr=10.^(snr_db./10); temp=sqrt(snr./(1+snr)); BER_THEROY=(1-temp)/2; BER_T=[BER_T,BER_THEROY]; end i=0:1:N_snr; semilogy(i,BER(1,:),'-r',i,BER(2,:),'ob',i,BER_T ,'*g'); xlabel('E_b/N_0(dB)') ylabel('BER') legend('User1 RAKE','User2 RAKE', 'Theoretical flat fading');
B.
no need
C.
no need
D.
no need
查看完整题目与答案
【单选题】听力原文：Members of the I.M.F. approved reform. measures that aim to increase the voting power of countries with growing economies. As a first step, they agreed to increases in the voting rights for China...
A.
正确
B.
错误
查看完整题目与答案
【简答题】(A)daydream (B)disagreement (C)factually (D)if (E)inevitable (F)inseparable (G)lays (H) (I)perspective (J)resides (K)that (L)thinking (M)thoughtfully (N)ultimately (O)wake To some thinkers, it...
查看完整题目与答案
【判断题】仓库配送服务就是对客户商品物流的保证，要符合客户所期望的质量，在客户希望的时间内配送商品，不惜成本也要满足客户需求。
A.
正确
B.
错误
查看完整题目与答案
【判断题】擦洗附件及整机外观，检查各传动部分、润滑系统、冷却系统确认无误后，先手动后机动试车，使机床正常运转。
A.
正确
B.
错误
查看完整题目与答案
【单选题】What view did the three Milesian philosophers share?
A.
They all believed that the mythology had a basis in fact.
B.
They introduced a scientific approach to explaining nature.
C.
They thought that water was the original element.
D.
They all agreed with the teachings of Socrates.
查看完整题目与答案
【单选题】为了防止麻醉废气污染对手术室工作人员的健康造成不良影响,下列关于麻醉废气污染防护措施的叙述不正确的是
A.
改善手术室的通风条件，建立完备的排放系统
B.
实施手术室工作岗位的轮换制度
C.
女性孕期适当减少手术间工作
D.
提高手术室的工作效率
E.
选用密闭性能好的麻醉机
查看完整题目与答案
【多选题】照明开关箱中电器配置的组合,主要有
A.
刀开关、熔断器、漏电保护器
B.
刀开关、断路器、漏电保护器
C.
刀开关、漏电断路器
D.
断路器、漏电保护器
查看完整题目与答案