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Strong NP-Hardness of Single Machine Scheduling Problems with Variable Processing Time
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作者 周贤伟 杜文 朱健梅 《Journal of Modern Transportation》 1998年第2期78-88,共11页
In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' ... In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' of the job on position i and a “normal' processing time of the job. The criteria considered is to minimize scheduled length of all jobs. A lemma is proposed and proved. In no deadline constrained condition, the problem belongs to polynomial time algorithm. It is proved by using 3 partition that if the problem is deadline constrained, its complexity is strong NP hard. Finally, a conjuncture is proposed that is to be proved. 展开更多
关键词 single machine scheduling problem variable processing time strong NP hardness.
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Optimal Rapid Restart of Heuristic Methods of NP Hard Problems
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作者 侯越先 王芳 《Transactions of Tianjin University》 EI CAS 2004年第2期146-148,共3页
Many heuristic search methods exhibit a remarkable variability in the time required to solve some particular problem instances. Their cost distributions are often heavy-tailed. It has been demonstrated that, in most c... Many heuristic search methods exhibit a remarkable variability in the time required to solve some particular problem instances. Their cost distributions are often heavy-tailed. It has been demonstrated that, in most cases, rapid restart (RR) method can prominently suppress the heavy-tailed nature of the instances and improve computation efficiency. However, it is usually time-consuming to check whether an algorithm on a specific instance is heavy-tailed or not. Moreover, if the heavy-tailed distribution is confirmed and the RR method is relevant, an optimal RR threshold should be chosen to facilitate the RR mechanism. In this paper, an approximate approach is proposed to quickly check whether an algorithm on a specific instance is heavy-tailed or not. The method is realized by means of calculating the maximal Lyapunov exponent of its generic running trace. Then a statistical formula to estimate the optimal RR threshold is educed. The method is based on common nonparametric estimation, e.g., Kernel estimation. Two heuristic methods are selected to verify our method. The experimental results are consistent with the theoretical consideration perfectly. 展开更多
关键词 NP hard problems heavy-tailed rapid restart(RR) Lyapunov exponent optimal RR threshold
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Concrete Physics Method for Solving NP hard Problem
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作者 Huang Wen\|qi College of Computer Science, Huazhong University of Science and Technology, Wuhan 430074,China Laboratory of Computer Science, Institute of Software, Chinese Academy of Sciences, Beijing 100080, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期140-146,共7页
With a NP hard problem given, we may find a equivalent physical world. The rule of the changing of the physical states is simply the algorithm for solving the original NP hard problem .It is the most natural algorithm... With a NP hard problem given, we may find a equivalent physical world. The rule of the changing of the physical states is simply the algorithm for solving the original NP hard problem .It is the most natural algorithm for solving NP hard problems. In this paper we deal with a famous example , the well known NP hard problem——Circles Packing. It shows that our algorithm is dramatically very efficient. We are inspired that, the concrete physics algorithm will always be very efficient for NP hard problem. 展开更多
关键词 concrete physics algorithm NP hard problem circles packing the rule of the changing of the physical states
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The Alleged Hard Problem: A Pseudo Problem
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作者 Michael Prost 《Journal of Philosophy Study》 2017年第3期111-124,共14页
One of the most intriguing problems of philosophy is the question whether the human mind and human consciousness can be completely reduced to matter, namely to the brain. A special problem in this context is what has ... One of the most intriguing problems of philosophy is the question whether the human mind and human consciousness can be completely reduced to matter, namely to the brain. A special problem in this context is what has been called the "hard problem." The hard problem denies that it is possible to reduce phenomenal experiences to brain states. The hard problem claims that it is impossible for materialists to explain what it is like to feel something. Here, we will prove that the hard problem is a pseudo problem that is based on errors in logic and language. One of the key arguments for the hard problem, the conceivability of zombies, is logically wrong within naturalism, which most philosophers acknowledge. Nevertheless, generally all questions of the type "What is it like to feel something?" are either trivial or linguistically impermissible. The core of the "hard problem" is the mix-up between non-reducibility and non-describability. 展开更多
关键词 human consciousness human mind NATURALISM zombie argument hard problem explanatory gap property dualism logic language
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The Hard Problem of Consciousness from a Bio-Psychological Perspective
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作者 Franz Klaus Jansen 《Journal of Philosophy Study》 2017年第11期579-594,共16页
Chalmers introduced the hard problem of consciousness as a profound gap between experience and physical concepts. Philosophical theories were based on different interpretations concerning the qualia/concept gap, such ... Chalmers introduced the hard problem of consciousness as a profound gap between experience and physical concepts. Philosophical theories were based on different interpretations concerning the qualia/concept gap, such as interactive dualism (Descartes), as well as mono aspect or dual aspect monism. From a bio-psychological perspective, the gap can be explained by the different activity of two mental functions realizing a mental representation of extra-mental reality. The function of elementary sensation requires active sense organs, which create an uninterrupted physical chain from extra-mental reality to the brain and reflect the present. The function of categorizing reflection no longer needs sense organs, so that the physical chain to extra-mental reality is interrupted and now reflects the past. Whereas elementary sensation is an open system, categorizing reflection remains a closed system, separated from extra-mental reality. This creates the potentiality/reality gap, since prediction from the closed to the open system remains always uncertain. Elementary sensation is associated to specific qualia for each sense organ. Chalmers also attributed qualia to thoughts, with more neutral thought qualia. Thus at the qualia level, there is also an important gap, but now between specific sense qualia and neutral thought qualia. Since all physical concepts are simultaneously linked to neutral thought qualia, the hard problem might be explained by a qualia/qualia gap instead of a qualia/concept gap. The mental function of categorizing reflection induces the change from sense qualia to thought qualia by a categorization process. The specific sense qualia mosaic of an apple is reduced to physical concepts with neutral qualia by progressive categorization first to fruit, then to food, to chemicals and finally to calories. This might explain the gap felt in the hard problem, since specific sense qualia are completely different from neutral thought qualia, so that the hard problem could already be encountered at the qualia level. Since the gap of the hard problem is due to the interaction of different mental functions, it is compatible with a philosophical monism. 展开更多
关键词 hard problem bio-psychological perception mental functions qualia mosaic sense qualia thoughtqualia thought concepts brain locations
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A Class of Single Machine Scheduling Problems with Variable Processing Time
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作者 周荷芳 周贤伟 《Journal of Modern Transportation》 2001年第1期93-100,共8页
In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and... In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and so on. The complexity of the problem is determined. [WT5HZ] 展开更多
关键词 single machine scheduling problem NP-hard variable processing time complexity theory
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新型配电系统故障恢复优化NP-hard问题的无损转化算法
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作者 闫涛 《电网技术》 北大核心 2025年第12期4957-4963,I0007,共8页
NP-hard(non-deterministic polynomial-time hard)问题中的多项式时间内“不可验证”问题是新型配电系统故障恢复优化背后的基础科学难题,传统的精确算法和近似算法均无法解决速度精度间不可调和的矛盾。针对传统算法的不足之处,提出... NP-hard(non-deterministic polynomial-time hard)问题中的多项式时间内“不可验证”问题是新型配电系统故障恢复优化背后的基础科学难题,传统的精确算法和近似算法均无法解决速度精度间不可调和的矛盾。针对传统算法的不足之处,提出了一种新型配电系统故障恢复优化NP-hard问题的无损转化算法,通过将“不可验证”问题无损转化为“可验证”问题,突破了速度精度难两全的技术瓶颈。首先借助时间复杂度函数阐明新型配电系统故障恢复优化属于NP-hard问题中的多项式时间内“不可验证”问题,并指出“不可验证”到“可验证”的无损转化是解决难题的关键;然后基于隐Markov模型和前向算法提出了一种无损转化算法,使用逆向搜索系统运行状态时变过程的驱动场景的全新算法逻辑,实现了指数级到多项式级的时间复杂度降维;最后算例分析展示了文中算法仅花费1.58%的计算时间便可获得“0”误差的精确解,证明了其具有兼顾速度与精度的优秀算法性能。 展开更多
关键词 新型配电系统 故障恢复优化 NP-hard问题 无损转化算法
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粮库PWSN部署中NP-Hard问题的研究 被引量:1
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作者 陈得民 张元 +1 位作者 廉飞宇 张秋闻 《河南工业大学学报(自然科学版)》 CAS 北大核心 2008年第4期6-9,19,共5页
以无线传感器网络在粮库中的应用为例,将传感器节点部署中出现未覆盖区域问题归属为NP-Hard问题.结合近似算法、Bidding协议、Voronoi diagrams等方法,对粮库PWSN部署中的NP-Hard问题进行了较深入的研究,对解决粮库无线传感器网络的覆... 以无线传感器网络在粮库中的应用为例,将传感器节点部署中出现未覆盖区域问题归属为NP-Hard问题.结合近似算法、Bidding协议、Voronoi diagrams等方法,对粮库PWSN部署中的NP-Hard问题进行了较深入的研究,对解决粮库无线传感器网络的覆盖问题提出了新思路. 展开更多
关键词 覆盖问题 PWSN NP—hard
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Study on the Inventory Routing Problem of Refined Oil Distribution Based on Working Time Equilibrium 被引量:6
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作者 Zhenping Li Zhiguo Wu 《American Journal of Operations Research》 2016年第1期17-24,共8页
Taking the distribution route optimization of refined oil as background, this paper studies the inventory routing problem of refined oil distribution based on working time equilibrium. In consideration of the constrai... Taking the distribution route optimization of refined oil as background, this paper studies the inventory routing problem of refined oil distribution based on working time equilibrium. In consideration of the constraints of vehicle capacity, time window for unloading oil, service time and demand of each gas station, we take the working time equilibrium of each vehicle as goal and establish an integer programming model for the vehicle routing problem of refined oil distribution, the objective function of the model is to minimize the maximum working time of vehicles. To solve this model, a Lingo program was written and a heuristic algorithm was designed. We further use the random generation method to produce an example with 10 gas stations. The local optimal solution and approximate optimal solution are obtained by using Lingo software and heuristic algorithm respectively. By comparing the approximate optimal solution obtained by heuristic algorithm with the local optimal solution obtained by Lingo software, the feasibility of the model and the effectiveness of the heuristic algorithm are verified. The results of this paper provide a theoretical basis for the scheduling department to formulate the oil distribution plan. 展开更多
关键词 Working Time Equilibrium hard Time Window Inventory Routing problem Mathematical Model Heuristic Algorithm
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Key Exchange Protocol Based on Tensor Decomposition Problem 被引量:1
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作者 MAO Shaowu ZHANG Huanguo +3 位作者 WU Wanqing ZHANG Pei SONG Jun LIU Jinhui 《China Communications》 SCIE CSCD 2016年第3期174-183,共10页
The hardness of tensor decomposition problem has many achievements, but limited applications in cryptography, and the tensor decomposition problem has been considered to have the potential to resist quantum computing.... The hardness of tensor decomposition problem has many achievements, but limited applications in cryptography, and the tensor decomposition problem has been considered to have the potential to resist quantum computing. In this paper, we firstly proposed a new variant of tensor decomposition problem, then two one-way functions are proposed based on the hard problem. Secondly we propose a key exchange protocol based on the one-way functions, then the security analysis, efficiency, recommended parameters and etc. are also given. The analyses show that our scheme has the following characteristics: easy to implement in software and hardware, security can be reduced to hard problems, and it has the potential to resist quantum computing.Besides the new key exchange can be as an alternative comparing with other classical key protocols. 展开更多
关键词 key exchange resistant quantum hard problem tensor decomposition
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DVE场景精简的NP-Hard问题及其近似算法
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作者 陈庆 贾金原 《系统仿真学报》 CAS CSCD 北大核心 2008年第S1期21-24,共4页
高效的网格精简算法对于大规模DVE场景的实时绘制与传输均十分重要。目前已经提出了大量关于网格精简方法,但绝大多数网格优化算法都是面向实际应用的。我们却从计算机科学理论的角度出发,对这一经典问题重新进行了深入研究。首先,我们... 高效的网格精简算法对于大规模DVE场景的实时绘制与传输均十分重要。目前已经提出了大量关于网格精简方法,但绝大多数网格优化算法都是面向实际应用的。我们却从计算机科学理论的角度出发,对这一经典问题重新进行了深入研究。首先,我们发现网格精简是一个最优顶点覆盖问题,即NP-Hard问题。然后,我们又提出了一种基于贪心算法的用于网格精简的最优顶点覆盖问题的近似算法。理论推导与实验数据都说明本文所给出的近似算法有效地减少了DVE场景的网格数量,能进一步提高DVE场景数据的网络传输速度。 展开更多
关键词 虚拟现实 NP-hard问题 顶点覆盖 近似算法 贪心算法 网格精简
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Number of Tardy Jobs of Single Machine Scheduling Problem with Variable Processing Time
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作者 朱健梅 《Journal of Modern Transportation》 1999年第1期88-95,共8页
The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved ... The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved by 3 partition problem that if the problem is of ready time and common deadline constrained, its complexity is NP hard in the strong sense. Finally, a polynomial algorithm for solving unit processing time and common deadline problems is proposed. 展开更多
关键词 NUMBER of tardy JOBS single machine scheduling problem VARIABLE processing time STRONG NP hardNESS algorithm.
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Solving the Traveling Salesman Problem Using Hydrological Cycle Algorithm 被引量:1
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作者 Ahmad Wedyan Jacqueline Whalley Ajit Narayanan 《American Journal of Operations Research》 2018年第3期133-166,共34页
In this paper, a recently developed nature-inspired optimization algorithm called the hydrological cycle algorithm (HCA) is evaluated on the traveling salesman problem (TSP). The HCA is based on the continuous movemen... In this paper, a recently developed nature-inspired optimization algorithm called the hydrological cycle algorithm (HCA) is evaluated on the traveling salesman problem (TSP). The HCA is based on the continuous movement of water drops in the natural hydrological cycle. The HCA performance is tested on various geometric structures and standard benchmarks instances. The HCA has successfully solved TSPs and obtained the optimal solution for 20 of 24 benchmarked instances, and near-optimal for the rest. The obtained results illustrate the efficiency of using HCA for solving discrete domain optimization problems. The solution quality and number of iterations were compared with those of other metaheuristic algorithms. The comparisons demonstrate the effectiveness of the HCA. 展开更多
关键词 WATER-BASED OPTIMIZATION Algorithms Nature-Inspired Computing Discrete OPTIMIZATION problems NP-hard problems
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Solution to the Balanced Academic Curriculum Problem Using Tabu Search
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作者 Lorna V. Rosas-Tellez Jose L. Martinez-Florest Vittorio Zanella-Palacios 《Computer Technology and Application》 2012年第9期630-635,共6页
The Balanced Academic Curriculum Problem (BACP) is a constraint satisfaction problem classified as (Non-deterministic Polynomial-time Hard) NP-Hard. This problem consists in the allocation of courses in the period... The Balanced Academic Curriculum Problem (BACP) is a constraint satisfaction problem classified as (Non-deterministic Polynomial-time Hard) NP-Hard. This problem consists in the allocation of courses in the periods that are part of a curriculum such that the prerequisites are satisfied and the load of courses is balanced for the students. This paper presents the solution for a modified BACP where the academic loads and number of curses may be the same or different for each one of the periods and allows having some courses in a specific period. This problem is modeled as an integer programming problem and is proposed the use of Tabu search with short-term memory for its solution because it is not possible to find solutions for all the instances of this modified problem with an exact method. 展开更多
关键词 Balanced academic curriculum problem (BACP) Tabu search non-deterministic polynomial-time hard (NP-hard).
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Improved Parallel Three-List Algorithm for the Knapsack Problem without Memory Conflicts
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作者 潘军 李肯立 李庆华 《Journal of Southwest Jiaotong University(English Edition)》 2006年第1期7-14,共8页
Based on the two-list algorithm and the parallel three-list algorithm, an improved parallel three-list algorithm for knapsack problem is proposed, in which the method of divide and conquer, and parallel merging withou... Based on the two-list algorithm and the parallel three-list algorithm, an improved parallel three-list algorithm for knapsack problem is proposed, in which the method of divide and conquer, and parallel merging without memory conflicts are adopted. To find a solution for the n-element knapsack problem, the proposed algorithm needs O(2^3n/8) time when O(2^3n/8) shared memory units and O(2^n/4) processors are available. The comparisons between the proposed algorithm and 10 existing algorithms show that the improved parallel three-fist algorithm is the first exclusive-read exclusive-write (EREW) parallel algorithm that can solve the knapsack instances in less than O(2^n/2) time when the available hardware resource is smaller than O(2^n/2) , and hence is an improved result over the past researches. 展开更多
关键词 Knapsack problem NP-hard Parallel algorithm Memory conflicts hardware-time tradeoff
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An Efficient Proximal Point Algorithm for Unweighted Max-Min Dispersion Problem
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作者 Siqi Tao 《Advances in Pure Mathematics》 2018年第4期400-407,共8页
In this paper, we first reformulate the max-min dispersion problem as a saddle-point problem. Specifically, we introduce an auxiliary problem whose optimum value gives an upper bound on that of the original problem. T... In this paper, we first reformulate the max-min dispersion problem as a saddle-point problem. Specifically, we introduce an auxiliary problem whose optimum value gives an upper bound on that of the original problem. Then we propose the saddle-point problem to be solved by an adaptive custom proximal point algorithm. Numerical results show that the proposed algorithm is efficient. 展开更多
关键词 Maximum Weighted DISPERSION problem Adaptive CUSTOM PROXIMAL Point Al-gorithm NP-hard
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意识体验的非感知性
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作者 陈昊 《科学技术哲学研究》 北大核心 2025年第2期13-20,共8页
感知虽然与意识体验紧密相关,但其本身不是主观体验。感知与意识概念二者之间的复杂关系导致解释意识“难问题”时常常会滑向意识的“易问题”。从概念演变历史看,感知与意识的内涵虽然有重叠,但是二者在不同时期有明显差异并逐渐细分,... 感知虽然与意识体验紧密相关,但其本身不是主观体验。感知与意识概念二者之间的复杂关系导致解释意识“难问题”时常常会滑向意识的“易问题”。从概念演变历史看,感知与意识的内涵虽然有重叠,但是二者在不同时期有明显差异并逐渐细分,现代哲学意义下的感知更强调对信息的搜索、接收和处理。在此意义下,我感知和非我感知中的“感知”含义有重要差别,感知主体具有非我性,而将感知引入意识“难问题”会导致主观体验的客体化。因此,探讨意识“难问题”时需要对感知和主观体验进行必要的划界,感知不应该视为意识主观体验最本质的部分。 展开更多
关键词 感知 意识“难问题” 主观体验
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弥合鸿沟:意识难问题的“情绪中间态”解释
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作者 陈昊 《自然辩证法通讯》 北大核心 2025年第6期50-58,共9页
意识难问题的解释目标包含两个问题:一是解释物理过程如何以及为什么会产生具有现象特征的经验;二是解释现象意识本身的本质。为了同时解决这两个问题,可在物理过程和主观体验之间引入一个中间态,这个中间态与物理过程构成解释关系、与... 意识难问题的解释目标包含两个问题:一是解释物理过程如何以及为什么会产生具有现象特征的经验;二是解释现象意识本身的本质。为了同时解决这两个问题,可在物理过程和主观体验之间引入一个中间态,这个中间态与物理过程构成解释关系、与主观体验构成解释和表征关系。由于情绪本质上是生物体的一种状态转变过程,这个过程包含了生物体的行动倾向,构成了主体体验,而同一情绪过程中不同的行动倾向差异又会指向体验的主体,进而呈现出具有自我特征的主观体验。由此,通过论证情绪作为一种中间态过程,不仅表明了难问题中物理过程到主观体验的解释限度,而且给出了从物理过程、情绪变化过程、主体体验到主观体验的解释逻辑,为理解意识难问题提供了新的思路。 展开更多
关键词 难问题 解释模式 中间态 高阶意识 情绪
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基于深度强化学习的整数规划算法优化 被引量:1
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作者 吴闻笛 吴征天 《苏州科技大学学报(自然科学版)》 2025年第2期76-84,共9页
整数规划问题在经济、工业生产、管理调度等领域有着广泛应用。然而解决此类问题常用的传统方法大多都是依赖人工设计的启发式算法,该算法已经逐渐不能满足大规模问题下实时性求解的要求。论文将深度强化学习应用于对整数规划的分布式... 整数规划问题在经济、工业生产、管理调度等领域有着广泛应用。然而解决此类问题常用的传统方法大多都是依赖人工设计的启发式算法,该算法已经逐渐不能满足大规模问题下实时性求解的要求。论文将深度强化学习应用于对整数规划的分布式可行域切割的序贯决策问题中,设计并构建了状态与动作空间以及奖励函数,并结合注意力机制与LSTM网络来训练了强化学习代理,以解决整数规划问题中可行域分割的切割平面选择的问题。实验结果表明,该策略方法能有效进行Gomory切割平面的选择,且拥有相对稳定的切割质量。 展开更多
关键词 整数规划 强化学习 算法优化 NP-hard问题
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基于反馈评分与前向预测的最大公共诱导子图算法
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作者 孙轲 刘燕丽 黄志浩 《软件工程》 2025年第8期15-21,共7页
基于强化学习的最大公共诱导子图(Maximum Common Induced Subgraph,MCIS)算法在处理历史搜索中低频出现的顶点时存在局限,难以评估其真实重要性并进行有效探索。为此,提出一种基于动作与环境反馈的前向预测方法。动作反馈通过奖励机制... 基于强化学习的最大公共诱导子图(Maximum Common Induced Subgraph,MCIS)算法在处理历史搜索中低频出现的顶点时存在局限,难以评估其真实重要性并进行有效探索。为此,提出一种基于动作与环境反馈的前向预测方法。动作反馈通过奖励机制量化分支顶点的剪枝效果,环境反馈则用双域个数来表征待搜索子图的大小。前向预测通过单边采样选择顶点模拟分支,并根据反馈确定最佳顶点。实验结果表明,新算法McSplitLA比McSplitDAL多解决7个算例,平均求解时间减少11.2%~17.9%,有效提高了剪枝率并优化了探索方向。 展开更多
关键词 NP难问题 强化学习 最大公共诱导子图 分支策略
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