In this paper, we propose a log-normal linear model whose errors are first-order correlated, and suggest a two-stage method for the efficient estimation of the conditional mean of the response variable at the original...In this paper, we propose a log-normal linear model whose errors are first-order correlated, and suggest a two-stage method for the efficient estimation of the conditional mean of the response variable at the original scale. We obtain two estimators which minimize the asymptotic mean squared error （MM） and the asymptotic bias （MB）, respectively. Both the estimators are very easy to implement, and simulation studies show that they are perform better.展开更多
Due to the complexity of the composite fading channel, a new simplified channel model is proposed to analyze the bit error ratio（BER） performance of the distributed antenna system （DAS）. First, instead of the gamm...Due to the complexity of the composite fading channel, a new simplified channel model is proposed to analyze the bit error ratio（BER） performance of the distributed antenna system （DAS）. First, instead of the gamma-log-normal distribution, the log-normal distribution is applied to describe the output signal to noise ratio（SNR） after maximal ratio combining （MRC） at the receiver. Then, assuming that the channel state information（CSI） is available to the transmitter, by employing the Gauss-Hermite integral, an approximate analytical expression of the BER is derived for the downlink of the DAS with antenna selective transmission and MRC. Finally, the results of a Monte Carlo simulation show that the analytical results match the simulation results. Therefore, it can be concluded that the proposed approximate channel model is effective and accurate, and the derived analytical expression can be used to evaluate the real system performance.展开更多
Software application is still a heavy dependence for most of the business operation today.Whenever software application encounters error that causes downtime in the production environment,the root cause of the error c...Software application is still a heavy dependence for most of the business operation today.Whenever software application encounters error that causes downtime in the production environment,the root cause of the error can be either within the software application layer or any other factor outside the software application layer.To accurately identify the root cause is difficult whenever more than one log file is required for the root cause analysis activity.Due to such complexity,it leads to the entire duration on the root cause analysis activity became prolong.This will increase the total time taken on restoring the software application service back to the users.In order to identify the root cause of software application error in a more accurate manner,and shorten the duration of root cause analysis activity conducting on software application error,a Prescriptive Analytical Logic Model incorporates with Analytic Hierarchy Process(AHP)is proposed.The proposed Logic Model along with the algorithm will contribute a new knowledge in the area of log file analysis to shorten the total time spent on root cause analysis activity.展开更多
基金The NSF(11271155) of ChinaResearch Fund(20070183023) for the Doctoral Program of Higher Education
文摘In this paper, we propose a log-normal linear model whose errors are first-order correlated, and suggest a two-stage method for the efficient estimation of the conditional mean of the response variable at the original scale. We obtain two estimators which minimize the asymptotic mean squared error （MM） and the asymptotic bias （MB）, respectively. Both the estimators are very easy to implement, and simulation studies show that they are perform better.
基金The National High Technology Research and Development Program of China (863Program) (No.2007AA01Z207,2007AA01Z268)Program for New Century Excellent Talents in UniversityResearch Fund of National Mobile Communications Research Laboratory of Southeast University(No.2008A06)
文摘Due to the complexity of the composite fading channel, a new simplified channel model is proposed to analyze the bit error ratio（BER） performance of the distributed antenna system （DAS）. First, instead of the gamma-log-normal distribution, the log-normal distribution is applied to describe the output signal to noise ratio（SNR） after maximal ratio combining （MRC） at the receiver. Then, assuming that the channel state information（CSI） is available to the transmitter, by employing the Gauss-Hermite integral, an approximate analytical expression of the BER is derived for the downlink of the DAS with antenna selective transmission and MRC. Finally, the results of a Monte Carlo simulation show that the analytical results match the simulation results. Therefore, it can be concluded that the proposed approximate channel model is effective and accurate, and the derived analytical expression can be used to evaluate the real system performance.
文摘Software application is still a heavy dependence for most of the business operation today.Whenever software application encounters error that causes downtime in the production environment,the root cause of the error can be either within the software application layer or any other factor outside the software application layer.To accurately identify the root cause is difficult whenever more than one log file is required for the root cause analysis activity.Due to such complexity,it leads to the entire duration on the root cause analysis activity became prolong.This will increase the total time taken on restoring the software application service back to the users.In order to identify the root cause of software application error in a more accurate manner,and shorten the duration of root cause analysis activity conducting on software application error,a Prescriptive Analytical Logic Model incorporates with Analytic Hierarchy Process(AHP)is proposed.The proposed Logic Model along with the algorithm will contribute a new knowledge in the area of log file analysis to shorten the total time spent on root cause analysis activity.
