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Combined heuristics for determining order quantity under time-varying demands
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作者 Tang Jiafu Pan Zhendong Gong Jun Liu Shixin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期99-111,共13页
The time-varying demands for a certain period are often assumed to be less than the basic economic order quantity (EOQ) so that total replenishment quantity rather than economic order quantity is normally considered... The time-varying demands for a certain period are often assumed to be less than the basic economic order quantity (EOQ) so that total replenishment quantity rather than economic order quantity is normally considered by most of the heuristics. This acticle focuses on a combined heuristics method for determining order quantity under generalized time-varying demands. The independent policy (IP), abnormal independent policy (AIP) and dependent policies are studied and compared. Using the concepts of normal/abnormal periods and the properties of dependent policies, a dependent policy-based heuristics (DPH) is proposed for solving the order quantity problems with a kind of time-varying demands pattern under which the first period is normal. By merging the Silver-Meal (S-M) heuristics and the dependent policy-based heuristics (DPH), a combined heuristics (DPH/S-M) is developed for solving order quantity problems with generalized time-varying demands. The experimentation shows that (1) for the problem with one normal period, no matter which position the normal period stands, the DPH/S-M could not guarantee better than the S-M heuristics, however it is superior to the S-M heuristics in the case that the demands in the abnormal periods are in descending order, and (2) The DPH/S-M is superior to the S-M heuristics for problems with more than one normal period, and the more the number of normal periods, the greater the improvements. 展开更多
关键词 HEURISTICS EOQ time-varying demands inventory management
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A super-network equilibrium optimization method for operation architecture with fuzzy demands 被引量:3
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作者 XING Qinghua GAO Jiale 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期969-982,共14页
From the view of information flow, a super-network equilibrium optimization model is proposed to compute the solution of the operation architecture which is made up of a perceptive level, a command level and a firepow... From the view of information flow, a super-network equilibrium optimization model is proposed to compute the solution of the operation architecture which is made up of a perceptive level, a command level and a firepower level. Firstly, the optimized conditions of the perceptive level, command level and firepower level are analyzed respectively based on the demand of information relation,and then the information supply-and-demand equilibrium model of the operation architecture super-network is established. Secondly,a variational inequality transformation(VIT) model for equilibrium optimization of the operation architecture is given. Thirdly, the contraction projection algorithm for solving the operation architecture super-network equilibrium optimization model with fuzzy demands is designed. Finally, numerical examples are given to prove the validity and rationality of the proposed method, and the influence of fuzzy demands on the super-network equilibrium solution of operation architecture is discussed. 展开更多
关键词 super-network equilibrium operation architecture fuzzy demand information flow variational inequality transformation
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汉江中下游河道基本生态需水与生径比分析 被引量:15
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作者 朱才荣 张翔 穆宏强 《人民长江》 北大核心 2014年第12期10-15,共6页
生态需水量的确定关系到河流生态恢复及地区经济与环境协调发展,是维系生态系统平衡的保障。为降低单一计算方法带来的误差,利用7Q10法、NGPRP法及Texas法等9种水文学方法对汉江中下游基本生态需水量进行了计算,并对其结果统一用蒙大拿... 生态需水量的确定关系到河流生态恢复及地区经济与环境协调发展,是维系生态系统平衡的保障。为降低单一计算方法带来的误差,利用7Q10法、NGPRP法及Texas法等9种水文学方法对汉江中下游基本生态需水量进行了计算,并对其结果统一用蒙大拿法进行归类,得出基于蒙大拿法的合理生态需水量。同时,从众多生态需水概念中提出了表征生态需水动态特性的生径比概念,并用蒙大拿法、Texas法、逐月频率计算法、月保证率设定法及其改进法计算了汉江中下游汛期与非汛期的生径比。 展开更多
关键词 水文学方法 生态需水量 生径比 汉江中下游 ratio of eco-water demands to STREAM flow ( REF)
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基于自忆性原理和EMD的中国清洁能源需求组合预测 被引量:1
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作者 汪哲荪 袁潇晨 +2 位作者 魏一鸣 金菊良 焦建玲 《水电能源科学》 北大核心 2010年第9期171-174,170,共5页
以中国历年能源消费量为基础,分别建立灰色自忆性预测模型和数据机理自忆性预测模型;利用经验模态分解方法分析中国能源消费增长率在经济、人口、城市化下的变化情况,并建立基于经验模态分解的BP神经网络预测模型;通过遗传算法构建能源... 以中国历年能源消费量为基础,分别建立灰色自忆性预测模型和数据机理自忆性预测模型;利用经验模态分解方法分析中国能源消费增长率在经济、人口、城市化下的变化情况,并建立基于经验模态分解的BP神经网络预测模型;通过遗传算法构建能源需求总量组合预测模型,求得中国清洁能源需求总量.研究结果表明:组合预测能够充分利用多个模型的丰富信息,提高预测的准确性;2020年中国清洁能源需求量将达到5.02×108~8.26×108 tce,应优先开发清洁能源. 展开更多
关键词 自忆性 EMD 中国能源 清洁能源 能源需求量 组合预测模型 Empirical Mode Decomposition Based China Energy Demand CLEAN 神经网络预测模型 经验模态分解方法 需求总量 消费增长率 能源消费量 优先开发 遗传算法 变化情况 准确性
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基于多代理的Demand Bus模拟系统
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作者 熊李艳 刘志强 《计算机应用与软件》 CSCD 北大核心 2007年第7期126-128,共3页
Demand Bus系统作为解决城市交通堵塞的一种新的公共运输系统在世界各地备受关注。在分析Demand Bus系统特点的基础上,提出了一种基于Q语言的多代理模拟系统框架,并且实现一个原型系统,对我国大城市使用Demand Bus系统进行了简单的评价。
关键词 DEMAND Bus系统多代理Q语言模拟系统
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夏秋季珠江口水域COD、DO、营养盐分布特征及其富营养化评价 被引量:19
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作者 蔡阳扬 岑竞仪 +1 位作者 欧林坚 吕颂辉 《暨南大学学报(自然科学与医学版)》 CAS CSCD 北大核心 2014年第3期221-227,共7页
在2012年夏季(8月)和秋季(11月)对珠江口海域进行化学需氧量(COD)、溶解氧(DO)和氮磷营养盐调查分析,并研究了其分布特征,采用富营养化指数法和潜在性富营养化法对珠江口水体营养化状况进行了分析和评价.结果显示,珠江口海域COD质量浓... 在2012年夏季(8月)和秋季(11月)对珠江口海域进行化学需氧量(COD)、溶解氧(DO)和氮磷营养盐调查分析,并研究了其分布特征,采用富营养化指数法和潜在性富营养化法对珠江口水体营养化状况进行了分析和评价.结果显示,珠江口海域COD质量浓度较低,夏季平均值为1.85 mg/L,秋季为1.10 mg/L;DO质量浓度较高,夏季平均值为6.95 mg/L,秋季为7.63 mg/L;无机氮污染严重,平均质量浓度夏季为0.85 mg/L,秋季为0.79mg/L,总体上从北向南递减;无机磷秋季平均质量浓度(0.015 mg/L)显著低于夏季平均质量浓度(0.010 mg/L).富营养化严重海域主要集中在东北部及伶仃洋一带,基本呈自北向南逐级递减趋势.秋季富营养化程度显著高于夏季,珠江口海域基本上属于磷限制潜在性富营养水平. 展开更多
关键词 珠江口 chemical OXYGEN demand(COD) dissolved oxygen(DO) 氮磷营养盐 富营养化
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基于PSO优化的直接灰色模型在年用电量预测中的应用 被引量:2
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作者 王国栋 邱镇 +1 位作者 任燕峰 张小伟 《水电能源科学》 北大核心 2010年第10期148-150,共3页
将直接灰色预测模型引入城市电网年用电量预测中,避开了灰微分方程参数辨识时选取的背景值问题,以模型的还原值与实际值的平均相对误差最小化为优化目标,设计了求解该模型的粒子群优化算法,并与多种预测方法比较。结果表明,该方法合理... 将直接灰色预测模型引入城市电网年用电量预测中,避开了灰微分方程参数辨识时选取的背景值问题,以模型的还原值与实际值的平均相对误差最小化为优化目标,设计了求解该模型的粒子群优化算法,并与多种预测方法比较。结果表明,该方法合理、有效,预测精度较高。 展开更多
关键词 PSO 粒子群优化算法 灰色模型 年用电量预测 Based DEMAND Forecasting GREY Model 平均相对误差 灰色预测模型 灰微分方程 预测精度 优化目标 方法比较 城市电网 参数辨识 最小化 实际值 背景值 问题 设计
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城市土地供应机制初探 被引量:1
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作者 刘咏梅 王海龙 《现代城市研究》 1998年第1期36-39,62,共5页
本文在对目前我国城市土地供应的特点和存在问题进行分析的基础上,从城市土地供应总量控制和供需平衡的角度入手,对城市土地供应机制作粗浅探讨。
关键词 MECHANISM of LAND supply to CONTROL the quantity of LAND supply to BALANCE supply and DEMAND
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Mg2+对糖蜜酒精废醪液培养单针藻(Monoraphidium sp.FXY-10)油脂合成的影响 被引量:1
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作者 乔腾生 董训赞 +1 位作者 黄力 余旭亚 《海洋与湖沼》 CAS CSCD 北大核心 2019年第5期1043-1049,共7页
为拓展糖蜜酒精废醪液(molasses wastewater,MW)综合利用途径,本实验研究了在MW中添加Mg^2+对单针藻Monoraphidium sp.FXY-10生长和油脂含量影响,并考察了Mg^2+对MW中总氮、总磷、化学需氧量(chemical oxygen demand,COD)的移除率。结... 为拓展糖蜜酒精废醪液(molasses wastewater,MW)综合利用途径,本实验研究了在MW中添加Mg^2+对单针藻Monoraphidium sp.FXY-10生长和油脂含量影响,并考察了Mg^2+对MW中总氮、总磷、化学需氧量(chemical oxygen demand,COD)的移除率。结果显示:当Mg^2+浓度为800μmol/L时,微藻的生物量和油脂含量达到最高,为0.91g/L和59.58%,分别是对照组的1.62和1.26倍;CO2固定效率比对照增加了95.15%;总氮、总磷、COD的移除率分别达到88.37%、93.69%和87.98%。研究表明,适宜浓度的Mg^2+可以促进MW中微藻生长和油脂含量的积累,将废水的处理和微藻油脂制备相结合,是微藻资源化利用的另一策略。 展开更多
关键词 糖蜜酒精废醪液 单针藻 MG^2+ 油脂 化学需氧量(chemical OXYGEN demand COD)
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Treatment of flotation wastewater using biological activated carbon 被引量:10
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作者 董颖博 林海 +1 位作者 刘泉利 霍汉鑫 《Journal of Central South University》 SCIE EI CAS 2014年第9期3580-3587,共8页
A laboratory scale up-flow biological activated carbon(BAC) reactor was constructed for the advanced treatment of synthetic flotation wastewater. Biodegradation of a common collector(i.e., ethyl xanthate) for non-ferr... A laboratory scale up-flow biological activated carbon(BAC) reactor was constructed for the advanced treatment of synthetic flotation wastewater. Biodegradation of a common collector(i.e., ethyl xanthate) for non-ferrous metallic ore flotation was evaluated. The results show that the two stages of domestication can improve microbial degradation ability. The BAC reactor obtains a chemical oxygen demand(COD) reduction rate of 82.5% for ethyl xanthate and its effluent COD concentration lowers to below 20 mg/L. The kinetics equation of the BAC reactor proves that the activated carbon layers at the height of 0 mm to 70 mm play a key role in the removal of flotation reagents. Ultraviolet spectral analysis indicates that most of the ethyl xanthate are degraded by microorganisms after advanced treatment by the BAC reactor. 展开更多
关键词 flotation wastewater biological activated carbon BIODEGRADATION chemical oxygen demand
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基于Test on Demand平台的弹上电缆自动测试系统的研制与设计实现 被引量:7
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作者 刘昕 方卫 《仪器仪表学报》 EI CAS CSCD 北大核心 2013年第S1期67-71,共5页
弹上电缆,作为导弹设备进行信号、能量传输的重要载体,质量是否符合要求,直接决定了设备的可靠性。与传统电缆不同,弹上电缆,具备多芯、多头、大规模等特点。传统的测试设备往往存在线缆支持规模较小、测试针对性太强、扩展性差、自动... 弹上电缆,作为导弹设备进行信号、能量传输的重要载体,质量是否符合要求,直接决定了设备的可靠性。与传统电缆不同,弹上电缆,具备多芯、多头、大规模等特点。传统的测试设备往往存在线缆支持规模较小、测试针对性太强、扩展性差、自动化程度低等缺点,本文提出了基于Test On Demand平台的弹上电缆测技术,阐述了测试原理和测试流程设计,使用该技术完成了对最多达300芯弹上电缆的导通、绝缘、耐压测试,可扩展多种型号电缆,具备通用性、扩展性强、测试速度快、自动化程度高、智能化等特点。 展开更多
关键词 TEST On DEMAND 弹上电缆 测试流程
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System optimization-oriented spare parts dynamic configuration model for multi-echelon multi-indenture system 被引量:9
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作者 Minzhi Ruan Hua Li Jian Fu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期923-933,共11页
In order to optimize the spares configuration project at different stages during the life cycle, the factor of time is considered to relax the assumption of the spares steady demand in multi-echelon technique for reco... In order to optimize the spares configuration project at different stages during the life cycle, the factor of time is considered to relax the assumption of the spares steady demand in multi-echelon technique for recoverable item control (METRIC) theory. According to the method of systems analysis, the dynamic palm theorem is introduced to establish the prediction model of the spares demand rate, and its main influence factors are analyzed, based on which, the spares support effectiveness evaluation index system is studied, and the system optimization-oriented spares dynamic configuration method for multi-echelon multi-indenture system is proposed. Through the analysis of the optimization algorithm, the layered marginal algorithm is designed to improve the model calculation efficiency. In a given example, the multi-stage spares configuration project during its life cycle is gotten, the research result conforms to the actual status, and it can provide a new way for the spares dynamic optimization. 展开更多
关键词 system optimization spare parts dynamic demand support effectiveness multi-echelon multi-indenture layered marginal algorithm
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A new grey forecasting model based on BP neural network and Markov chain 被引量:6
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作者 李存斌 王恪铖 《Journal of Central South University of Technology》 EI 2007年第5期713-718,共6页
A new grey forecasting model based on BP neural network and Markov chain was proposed. In order to combine the grey forecasting model with neural network, an important theorem that the grey differential equation is eq... A new grey forecasting model based on BP neural network and Markov chain was proposed. In order to combine the grey forecasting model with neural network, an important theorem that the grey differential equation is equivalent to the time response model, was proved by analyzing the features of grey forecasting model(GM(1,1)). Based on this, the differential equation parameters were included in the network when the BP neural network was constructed, and the neural network was trained by extracting samples from grey system's known data. When BP network was converged, the whitened grey differential equation parameters were extracted and then the grey neural network forecasting model (GNNM(1,1)) was built. In order to reduce stochastic phenomenon in GNNM(1,1), the state transition probability between two states was defined and the Markov transition matrix was established by building the residual sequences between grey forecasting and actual value. Thus, the new grey forecasting model(MNNGM(1,1)) was proposed by combining Markov chain with GNNM(1,1). Based on the above discussion, three different approaches were put forward for forecasting China electricity demands. By comparing GM(1, 1) and GNNM(1,1) with the proposed model, the results indicate that the absolute mean error of MNNGM(1,1) is about 0.4 times of GNNM(1,1) and 0.2 times of GM(I, 1), and the mean square error of MNNGM(1,1) is about 0.25 times of GNNM(1,1) and 0.1 times of GM(1,1). 展开更多
关键词 grey forecasting model neural network Markov chain electricity demand forecasting
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Bayesian inference for ammunition demand based on Gompertz distribution 被引量:6
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作者 ZHAO Rudong SHI Xianming +2 位作者 WANG Qian SU Xiaobo SONG Xing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期567-577,共11页
Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference metho... Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference method for ammunition demand based on Gompertz distribution is proposed.The Bayesian inference model based on Gompertz distribution is constructed,and the system contribution degree is introduced to determine the weight of the multi-source information.In the case where the prior distribution is known and the distribution of the field data is unknown,the consistency test is performed on the prior information,and the consistency test problem is transformed into the goodness of the fit test problem.Then the Bayesian inference is solved by the Markov chain-Monte Carlo(MCMC)method,and the ammunition demand under different damage grades is gained.The example verifies the accuracy of this method and solves the problem of ammunition demand prediction in the case of insufficient samples. 展开更多
关键词 ammunition demand prediction Bayesian inference Gompertz distribution system contribution Markov chain-Monte Carlo(MCMC)method
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Hybrid LEAP modeling method for long-term energy demand forecasting of regions with limited statistical data 被引量:4
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作者 CHEN Rui RAO Zheng-hua LIAO Sheng-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2136-2148,共13页
An accurate long-term energy demand forecasting is essential for energy planning and policy making. However, due to the immature energy data collecting and statistical methods, the available data are usually limited i... An accurate long-term energy demand forecasting is essential for energy planning and policy making. However, due to the immature energy data collecting and statistical methods, the available data are usually limited in many regions. In this paper, on the basis of comprehensive literature review, we proposed a hybrid model based on the long-range alternative energy planning (LEAP) model to improve the accuracy of energy demand forecasting in these regions. By taking Hunan province, China as a typical case, the proposed hybrid model was applied to estimating the possible future energy demand and energy-saving potentials in different sectors. The structure of LEAP model was estimated by Sankey energy flow, and Leslie matrix and autoregressive integrated moving average (ARIMA) models were used to predict the population, industrial structure and transportation turnover, respectively. Monte-Carlo method was employed to evaluate the uncertainty of forecasted results. The results showed that the hybrid model combined with scenario analysis provided a relatively accurate forecast for the long-term energy demand in regions with limited statistical data, and the average standard error of probabilistic distribution in 2030 energy demand was as low as 0.15. The prediction results could provide supportive references to identify energy-saving potentials and energy development pathways. 展开更多
关键词 energy demand forecasting with limited data hybrid LEAP model ARIMA model Leslie matrix Monte-Carlo method
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RS-SVM forecasting model and power supply-demand forecast 被引量:4
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作者 杨淑霞 曹原 +1 位作者 刘达 黄陈锋 《Journal of Central South University》 SCIE EI CAS 2011年第6期2074-2079,共6页
A support vector machine (SVM) forecasting model based on rough set (RS) data preprocess was proposed by combining the rough set attribute reduction and the support vector machine regression algorithm, because there a... A support vector machine (SVM) forecasting model based on rough set (RS) data preprocess was proposed by combining the rough set attribute reduction and the support vector machine regression algorithm, because there are strong complementarities between two models. Firstly, the rough set was used to reduce the condition attributes, then to eliminate the attributes that were redundant for the forecast, Secondly, it adopted the minimum condition attributes obtained by reduction and the corresponding original data to re-form a new training sample, which only kept the important attributes affecting the forecast accuracy. Finally, it studied and trained the SVM with the training samples after reduction, inputted the test samples re-formed by the minimum condition attributes and the corresponding original data, and then got the mapping relationship model between condition attributes and forecast variables after testing it. This model was used to forecast the power supply and demand. The results show that the average absolute error rate of power consumption of the whole society and yearly maximum load are 14.21% and 13.23%, respectively, which indicates that the RS-SVM forecast model has a higher degree of accuracy. 展开更多
关键词 rough set (RS) support vector machine (SVM) power supply and demand FORECAST
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Analysis and Research on Information Design of the Smart Community Pension Service 被引量:2
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作者 Chen Hao 《学术界》 CSSCI 北大核心 2018年第8期268-280,共13页
In the research on the smart community pension service,it is found that the problems encountered in the promotion of the smart pension can not be solved in the short term because of the lack of information and the acc... In the research on the smart community pension service,it is found that the problems encountered in the promotion of the smart pension can not be solved in the short term because of the lack of information and the acceptance of the intelligent products by the elderly. This paper puts forward the research ideas based on the cognitive characteristics and demand prediction of the specific population. Focusing on the research on the pension needs of people born in the 1960 s or 1970 s,it provides support for the solution of smart pension services in the peak period of aging population in the future. 展开更多
关键词 SMART COMMUNITY PENSION needs COGNITION of the ELDERLY information design DEMAND forecasting
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Regression model for daily passenger volume of high-speed railway line under capacity constraint 被引量:2
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作者 骆泳吉 刘军 +1 位作者 孙迅 赖晴鹰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3666-3676,共11页
A non-linear regression model is proposed to forecast the aggregated passenger volume of Beijing-Shanghai high-speed railway(HSR) line in China. Train services and temporal features of passenger volume are studied to ... A non-linear regression model is proposed to forecast the aggregated passenger volume of Beijing-Shanghai high-speed railway(HSR) line in China. Train services and temporal features of passenger volume are studied to have a prior knowledge about this high-speed railway line. Then, based on a theoretical curve that depicts the relationship among passenger demand, transportation capacity and passenger volume, a non-linear regression model is established with consideration of the effect of capacity constraint. Through experiments, it is found that the proposed model can perform better in both forecasting accuracy and stability compared with linear regression models and back-propagation neural networks. In addition to the forecasting ability, with a definite formation, the proposed model can be further used to forecast the effects of train planning policies. 展开更多
关键词 high-speed rail Jinghu high-speed railway(HSR) DEMAND capacity forecasting
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System of developing scale modeling and simulation for URAV 被引量:2
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作者 Jin Guodong Lu Libin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1295-1300,共6页
The unmanned reconnaissance aerial vehicle (URAV) plays an important role in battlefield monitoring and information acquiring because of its advantage of zero casualties, and has thus attracted considerable attentio... The unmanned reconnaissance aerial vehicle (URAV) plays an important role in battlefield monitoring and information acquiring because of its advantage of zero casualties, and has thus attracted considerable attention of the world. The URAV was developed rapidly in our country, however, no scientific assessment methods have yet been provided owing to different fight requirements of armed forces. Considering the demand of the missile artillery on the martial information, the model of information requirement of combat force, the reconnaissance ability of URAV, the survivability of URAV, and the task reliability of URAV were constructed, respectively. By synthesizing the mathematic models above, the model of developing demand was constructed on the URAV equipment. It simulated and calculated some URAV equipment developing scales, and explored a way of settling the problem of URAV equipment developing demand. 展开更多
关键词 unmanned reconnaissance aerial vehicle DEMAND SURVIVABILITY reliability
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Granular analyzing of weapon SoS demand description 被引量:2
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作者 Zhao Qingsong Yang Kewei Chen Yingwu Li Mengjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期565-570,共6页
The systematism of weapon combat is the typical characteristic of a modern battlefield. The process of combat is complex and the demand description of weapon system of systems (SOS) is difficult. Granular analyzing ... The systematism of weapon combat is the typical characteristic of a modern battlefield. The process of combat is complex and the demand description of weapon system of systems (SOS) is difficult. Granular analyzing is an important method for solving the complex problem in the world. Granular thinking is introduced into the demand description of weapon SoS. Granular computing and granular combination based on a relation of compatibility is proposed. Based on the level of degree and degree of detail, the granular resolution of weapon SoS is defined and an example is illustrated at the end. 展开更多
关键词 weapon SoS demand description granular analyzing granular resolution.
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