设 S 是 n 项可图序列, σ(S) 是 S 中的所有项之和, 设 H 是一个简单图, σ(H,n)是使得任意 n 项可图序列满足 σ(S) ≥ m , 则 S 有一个实现包含 H 作为子图的 m 的最小值, 本文给出了 σ(K p,1,1,...,1,n) 的...设 S 是 n 项可图序列, σ(S) 是 S 中的所有项之和, 设 H 是一个简单图, σ(H,n)是使得任意 n 项可图序列满足 σ(S) ≥ m , 则 S 有一个实现包含 H 作为子图的 m 的最小值, 本文给出了 σ(K p,1,1,...,1,n) 的下界并猜测对于所有的 n ≥ (t2 ) + 3p 此下界是可达到的.展开更多
In the paper, the (k-1)-traceable-nice ((k-1)-T-nice) and k-homogeneously-traceable-nice (k-HT-nice) sequence are defined similarly to the definition of k-Hamilton-nice (k-H-nice) and (k+1)-Hamilton-connec...In the paper, the (k-1)-traceable-nice ((k-1)-T-nice) and k-homogeneously-traceable-nice (k-HT-nice) sequence are defined similarly to the definition of k-Hamilton-nice (k-H-nice) and (k+1)-Hamilton-connected-nice ((k+1)-HC-nice) sequence. Therelationships among these four nice sequences are discussed. The main results are asfollows: Let<sub>η</sub>=(a<sub>1</sub>, a<sub>2</sub>,…, a<sub>k+1</sub> be a non-negative rational sequence, k≥2. (1) If η is(k+1)-HC-nice and a<sub>k+1</sub>=2, then η is k-HT-nice, (2) If η is k-HT-nice and a<sub>k+1</sub>=2,then η is (k-1)-T-nice, (3) If η is k-H-nice, then η is k-HT-nice. Meanwhile, four unsolvedproblems on these topics are proposed.展开更多
文摘设 S 是 n 项可图序列, σ(S) 是 S 中的所有项之和, 设 H 是一个简单图, σ(H,n)是使得任意 n 项可图序列满足 σ(S) ≥ m , 则 S 有一个实现包含 H 作为子图的 m 的最小值, 本文给出了 σ(K p,1,1,...,1,n) 的下界并猜测对于所有的 n ≥ (t2 ) + 3p 此下界是可达到的.
文摘为减少电力线信道时变性对自动抄表系统(automaticmeter-reading system,AMRS)计量数据传输效率的不利影响,提出了中继路由与分组队列相结合的方法。中继路由将整条通信链路分割成若干子链路,可以有效提高传输效率,但传输效率仍受制于信噪比(signal to noise ratio,SNR)最低的子链路。为充分利用每条子链路的最大传输效率,在中继路由的基础上,引入了分组队列机制。该方法根据接收和发送子链路的信道状况,动态调整分组队列长度,实现了发送子链路和接收子链路独立传输。由基于SNR的3状态Markov信道模型得到分组的平均发送次数,以该次数表示中继路由的分组接收速率和分组发送速率,建立了基于OPNET的M/M/1/K的AMRS分组排队模型。通过分析不同排队强度时的分组队列长度与队列延时等参数,验证了该方法能够提高传输效率。
基金This project is supported by the National Natural Science Foundation of China.
文摘In the paper, the (k-1)-traceable-nice ((k-1)-T-nice) and k-homogeneously-traceable-nice (k-HT-nice) sequence are defined similarly to the definition of k-Hamilton-nice (k-H-nice) and (k+1)-Hamilton-connected-nice ((k+1)-HC-nice) sequence. Therelationships among these four nice sequences are discussed. The main results are asfollows: Let<sub>η</sub>=(a<sub>1</sub>, a<sub>2</sub>,…, a<sub>k+1</sub> be a non-negative rational sequence, k≥2. (1) If η is(k+1)-HC-nice and a<sub>k+1</sub>=2, then η is k-HT-nice, (2) If η is k-HT-nice and a<sub>k+1</sub>=2,then η is (k-1)-T-nice, (3) If η is k-H-nice, then η is k-HT-nice. Meanwhile, four unsolvedproblems on these topics are proposed.