PON and WiMAX Convergence Network Planning Based on Mixed Integer Programming Model

This article analyzes the characteristics of PON and WiMAX convergence network planning.Based on user coverage ratio,WiMAX channel allocation,cell radius,carrier-to-noise ratio threshold,and bandwidth constraint,we propose a mixed integer programming model solved by a Branch-Band and Heuristic Search method.Finally,the simulation result is given and analyzed.The planning method based on a mixed integer programming model can save 20 percentage of the overall planning cost,compared with the greedy algorithm.The relationship between the convergence network planning cost and frequency usage is also analyzed.The optimized planning result with the lowest cost can be acquired through the best frequency usage.

Multi-period mine planning with multi-process routes

This paper attempts to optimize optimal capacities, block routing and mine sequencing problems in a mining system. The solution approach is based on a heuristics and the mixed integer programming (MIP). Unlike previous sequential solution approaches, the problems are herein solved at the same time. Furthermore, the proposed approach guarantees practical solutions because it considers ore material distribution within orebody. The paper has two main contributions: (a) the proposed approach generates production rates in a manner that the capacities are satisfied; (b) the proposed approach does not use pre-defined marginal cut-off grades. Thus, idle capacity problem is eliminated and different scheduling combinations are allowed. To see the performance of the approach proposed, a case study is carried out using a gold data. The schedule generated shows that the approach can determine optimal production rates, block destination and sequencing effectively.

Application value of mixed reality in hepatectomy for hepatocellular carcinoma

BACKGROUND As a new digital holographic imaging technology,mixed reality(MR)technology has unique advantages in determining the liver anatomy and location of tumor lesions.With the popularization of 5 G communication technology,MR shows great potential in preoperative planning and intraoperative navigation,making hepatectomy more accurate and safer.AIM To evaluate the application value of MR technology in hepatectomy for hepatocellular carcinoma(HCC).METHODS The clinical data of 95 patients who underwent open hepatectomy surgery for HCC between June 2018 and October 2020 at our hospital were analyzed retrospectively.We selected 95 patients with HCC according to the inclusion criteria and exclusion criteria.In 38 patients,hepatectomy was assisted by MR(Group A),and an additional 57 patients underwent traditional hepatectomy without MR(Group B).The perioperative outcomes of the two groups were collected and compared to evaluate the application value of MR in hepatectomy for patients with HCC.RESULTS We summarized the technical process of MR-assisted hepatectomy in the treatment of HCC.Compared to traditional hepatectomy in Group B,MR-assisted hepatectomy in Group A yielded a shorter operation time(202.86±46.02 min vs 229.52±57.13 min,P=0.003),less volume of bleeding(329.29±97.31 mL vs 398.23±159.61 mL,P=0.028),and shorter obstructive time of the portal vein(17.71±4.16 min vs 21.58±5.24 min,P=0.019).Group A had lower alanine aminotransferas and higher albumin values on the third day after the operation(119.74±29.08 U/L vs 135.53±36.68 U/L,P=0.029 and 33.60±3.21 g/L vs 31.80±3.51 g/L,P=0.014,respectively).The total postoperative complications and hospitalization days in Group A were significantly less than those in Group B[14(37.84%)vs 35(60.34%),P=0.032 and 12.05±4.04 d vs 13.78±4.13 d,P=0.049,respectively].CONCLUSION MR has some application value in three-dimensional visualization of the liver,surgical planning,and intraoperative navigation during hepatectomy,and it significantly improves the perioperative outcomes of hepatectomy for HCC.

Factors Related to Engaging in Physical Activity: A Mixed Methods Study of Female University Students

Objective: As a needs assessment for intervention, quantitative and qualitative methods were used to examine attitude, subjective norms, perceived behavioral control, intention, knowledge, and weight control status related to physical activity in female university students within the Theory of Planned Behavior (TPB). Methods: A two-phase mixed method design was used. In Phase I, 362 students participated in an online survey, and in Phase II, 33 students participated in five focus group discussions. Ages of participants ranged from 18 to 45 years old, with 18 - 25 year olds making up over 74% of the sample. Results: Attitude, subjective norms, and perceived behavioral control, along with weight control status of trying to lose weight, were found to be significant predictors of intention to follow physical activity recommendations, which in turn were the strongest predictor of physical activity. Knowledge was not found to be significant. Group discussions revealed barriers to meeting physical activity recommendations, which included lack of companionship and social support, lack of motivation, time and cost restrictions, and lack of privacy in the gym. Social norms exerted both positive and negative influences. Conclusion: The mixed method approach provided a deeper insight into the influential factors pertaining to physical activity among female students, and results could be used in further research to develop effective interventions.

Modeling and optimization methods of integrated production planning for steel plate mill with flexible customization

With diversified requirements and varying manufacturing environments, the optimal production planning for a steel mill becomes more flexible and complicated. The flexibility provides operators with auxiliary requirements through an implementable integrated production planning. In this paper, a mixed-integer nonlinear programming(MINLP) model is proposed for the optimal planning that incorporates various manufacturing constraints and flexibility in a steel plate mill. Furthermore, two solution strategies are developed to overcome the weakness in solving the MINLP problem directly. The first one is to transform the original MINLP formulation to an approximate mixed integer linear programming using a classic linearization method. The second one is to decompose the original model using a branch-and-bound based iterative method. Computational experiments on various instances are presented in terms of the effectiveness and applicability. The result shows that the second method performs better in computational efforts and solution accuracy.

Nuodeng Salt Village Under the View of Mixed Heritage

Located in Yunlong Dali, Nuodeng salt-village has thousands of years deep in Bai history, culture of the precipitation, the rich historical and cultural heritage of the Bai nationality. In Bai settlement formation and development history, its diverse natural appearances and rich cultural styles have the dual characteristics in natural and cultural heritage. Nuodeng salt-village is a connection between central plains culture and South Asia culture, also a complete ecological museum. By this time, this essay put Jinan springs under the view of mixed heritage based on the background of its history and geography, to identify the natural and cultural value of Nuodeng salt-village by comparison and conclude the heritage protection planning accordingly.

Planning a Sustainable New City

Pakistan, the sixth most populous country with 185 million people, grows in the last years at approximately 3.2 million people per year, generating a strong demand for new urban areas [1]. The Defense Housing Authority (DHA), among Pakistan’s most reputable land developers, has been instrumental in providing land for both residential and commercial use in several metropolitan areas. In Karachi, DHA has provided urban land in phases, with such land being most desirable to live and work, significantly improving the existing stock and allowing the growth of competitive economic activities. When DHA started Phase 10, at a distance of 55 km from the center of Karachi, the objective became to develop a self-sustained new city, although it should function as a satellite to the main metropolitan area. Pakistan has had a best experience from the planning of Islamabad by the legendary planner Constantinos Doxiadis, based on the Ekistics concept. So, the planners for the new city, called DHA City Karachi (DCK), also followed the Ekistics concept, enhanced to address the sustainability requirements of DHA. The resulting highly complex planning process, resulting from an uneven terrain and an irregular boundary, was possible to be carried out by employing advanced computer algorithms in the form of parametric design and GIS, tools that were unavailable to Doxiadis in the 60 s but fascinated him at the end of his professional life. This paper presents the sustainable planning approach for the new city of 600,000 people, handling physical constrains and site issues whilst ensuring adaptation to context. Then, the paper introduces how computing was employed towards applying Ekistics.

Stochastic Programming For Order Allocation And Production Planning

Stochastic demand is an important factor that heavily affects production planning.It influences activities such as purchasing,manufacturing,and selling,and quick adaption is required.In production planning,for reasons such as reducing costs and obtaining supplier discounts,many decisions must be made in the initial stage when demand has not been realized.The effects of non-optimal decisions will propagate to later stages,which can lead to losses due to overstocks or out-of-stocks.To find the optimal solutions for the initial and later stage regarding demand realization,this study proposes a stochastic two-stage linear program-ming model for a multi-supplier,multi-material,and multi-product purchasing and production planning process.The objective function is the expected total cost after two stages,and the results include detailed plans for purchasing and production in each demand scenario.Small-scale problems are solved through a deterministic equivalent transformation technique.To solve the problems in the large scale,an algorithm combining metaheuristic and sample average approximation is suggested.This algorithm can be implemented in parallel to utilize the power of the solver.The algorithm based on the observation that if the remaining quantity of materials and number of units of products at the end of the initial stage are given,then the problems of the first and second stages can be decomposed.

Hydrochemistry of the Mixed Dead Sea-Red Sea Water under Different Impoundment Scenarios as a Time Dependent State

The expected water mixing process between Red/Dead Sea water during the proposed conveyance projects is the main target of this research. The project will ensue transporting Red Sea water to recover and maintain certain level of the Dead Sea, mostly will reach -395 m. It is found that, the two different water bodies with different EC values or different densities (salinities) are relatively divided by stable plane. This plane is defined as the BARZACH PLANE. In this study, the mixing process occurred between the Red Sea with the Dead Sea waters, located at 20% - 24% of the Dead Sea column depth based on the Barzach Plane level. During a laboratory experimental work, it is found that the mixed Red/Dead Sea water evaporates in a high rate until certain level where the solution attains oversaturated conditions with different dissolved solids. At this stage, a thin layer of solids suddenly formed and floated at the surface of the dense brine. The salinity of the captured water is so dense that floated salt layer cannot be dissolved. In addition, the formed floated salt layer at the surface prevents the below captured water to evaporate and at this stage, stalactites start to form until the excess dissolved solids are not oversaturated with any mineral.

Design of Cellular Manufacturing Systems Considering Dynamic Production Planning and Worker Assignments

This article presents a comprehensive mathematical model for the design and analysis of Dynamic Cellular Manufacturing Systems （DCMS）. The proposed DCMS model considers several manufacturing attributes such as multi period production planning, dynamic system reconfiguration, duplicate machines, machine capacity, the available time for workers, worker assignments, and machine procurement. The objective is to minimize total costs; consisting of holding cost, outsourcing cost, inter-cell material handling cost, maintenance and overhead cost, machine relocation cost. While a study of published articles in the area of Cellular Manufacturing Systems （CMS） shows that workforce management issues have not sufficiently been addressed in the literature, the model presented also incorporates CMS workforce management issues such as salaries, hiring and firing costs of workers in addition to the manufacturing attributes. In-depth discussions on the results for two numerical examples are presented to illustrate applications of the proposed model. The model developed aims to raise the envelope by expanding and improving several CMS models previously presented in the literature.

Power Generation Expansion Planning Using an Interior Point with Cutting Plane （IP/CP） Method

The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point with cutting plane （IP/CP） method is proposed to solve the mixed-integer optimization problem of the electrical power generation expansion planning. The IP/CP method could improve the overall efficiency of the solution and reduce the computational time. Proposed method is combined with the Bender＇s decomposition technique in order to decompose the generation expansion problem into a master investment problem and a slave operational problem. The numerical example is presented to compare with the effectiveness of the proposed algorithm.

Strategic Robust Mixed Model Assembly Line Balancing Based on Scenario Planning

Assembly line balancing involves assigning a series of task elements to uniform sequential stations with certain restrictions. Decision makers often discover that a task assignment which is optimal with respect to a deterministic or stochastic/fuzzy model yields quite poor performance in reality. In real environments, assembly line balancing robustness is a more appropriate decision selection guide. A robust model based on the α worst case scenario is developed to compensate for the drawbacks of traditional robust criteria. A robust genetic algorithm is used to solve the problem. Comprehensive computational experiments to study the effect of the solution procedure show that the model generates more flexible robust solutions. Careful tuning the value of α allows the decision maker to balance robustness and conservativeness of as- sembly line task element assignments.

Evaluation of the impact of commodity price change on mine plan of underground mining

Fluctuations in commodity prices should influence mining operations to continually update and adjust their mine plans in order to capture additional value under new market conditions. One of the adjustments is the change in production sequencing. This paper seeks to present a method for quantifying the net present value(NPV) that may be directly attributed to the change in commodity prices. The evaluation is conducted across ten copper price scenarios. Discrete event simulation combined with mixed integer programming was used to attain a viable production strategy and to generate optimal mine plans. The analysis indicates that an increase in prices results in an increased in the NPV from$96.57M to $755.65M. In an environment where mining operations must be striving to gain as much value as possible from the rights to exploit a finite resource, it is not appropriate to keep operating under the same mine plan if commodity prices alter during the course of operations.

面向新工科的GIS空间分析混合式双语课程资源建设与教学实践

面向新工科、立德树人、思政教学、教学体系和行业发展等多重需求,本文阐述了GIS空间分析混合式双语课程的资源建设与教学实践。在课程资源建设方面,基于作者主编的中国煤炭教育协会“十四五”规划教材《GIS空间分析(双语版)》,为每一章节安排了思政教学内容,制作了对应的课程PPT课件、教学视频,并以此构建了线上线下混合式教学平台;在教学实践上,进行了产学研一体化的教学实践探索,开展了一流课程的申报与建设工作,为提升教学质量提供了重要保障。本课程在教学资源与教学实践方面的探索,为其他相关课程建设提供较为重要的参考和依据。

高速公路混合交通环境下的智能网联汽车换道策略研究

为推动智能网联汽车应用落地,提出高速公路混合交通环境下智能网联汽车换道策略。首先,改进NaSch元胞自动机模型,并采用马尔科夫链算法计算道路通行能力;其次,针对目标车道为专用车道和普通车道分别建立基于车速引导的决策模型和基于博弈论的双矩阵决策模型;最后,采用多目标轨迹优化算法优化换道轨迹。结果表明:目标车道为专用车道和普通车道时,所提出的策略可分别提高换道效率6%、3.38%。

高速公路客货混行交通流元胞传输模型

针对客货混行引发的交通流稳定性下降、交通安全风险增加以及运行效率降低等问题,构建一个多车道客货混行交通流元胞传输模型,从宏观角度研究不同货车渗透率下的高速公路客货混行交通流特性.首先,利用微观车辆跟驰模型,分析均质小汽车和货车交通流的基本图特征,提出不同货车渗透率下的客货混行交通流基本图模型.然后,采用具体参数表征换道、有限加速度造成的道路交通容量下降效应,刻画客货混行交通流中货车对直行和换道流量的影响,采用Logit模型计算多因素影响下的换道交通流量,构建多车道客货混行交通流元胞传输模型.最后,通过高速公路多场景仿真实验验证模型的有效性.研究结果表明:所提出的模型可准确模拟高速公路上的客货混行交通流演变过程;货车渗透率是影响混行交通运行的关键因素,在交通事件导致车道数减少时,货车渗透率超过0.6会导致交通拥堵难以消散.研究成果可为高速公路客货混行交通流特性研究提供分析工具,为客货混行下的交通管理和疏导策略制定提供理论方法.

既有铁路开行市域(郊)列车开行方案优化

研究目的:在利用既有铁路资源发展市域(郊)铁路的背景下,本文研究旨在提高市域(郊)铁路的运营效率,以满足乘客的出行需求。通过分析不同到达模式下的乘客行为,提出一种适应混合到达模式的市域(郊)客流分配方式。基于“线路国有、国铁与地方共营”管理模式,构建一个多目标优化模型,综合考虑乘客出行时间、运营成本和地方政府成本,并采用遗传粒子群优化算法求解,优化列车开行方案。研究结论:(1)通过对某条市域(郊)铁路线路早高峰时段客流数据的实证分析表明,构建的市域(郊)列车开行方案优化模型能够显著提高运营效率;(2)该模型早高峰时段缩短了乘客总旅行时间34.8%,降低了铁路局运营成本10.2%,减少地方政府成本11.5%,并节省了10%的车辆购置费用;(3)本研究成果可为利用既有铁路开行市域(郊)列车的项目规划决策和运营优化提供参考。

基于多Agent深度强化学习的无人机协作规划方法

人机协作控制是多无人机任务规划的重要方式。考虑多无人机任务环境协同解释和策略控制一致性需求,提出基于多Agent深度强化学习的无人机协作规划方法。依据任务知识和行为状态,构建基于任务分配Agent的任务规划器,生成人机交互的相互依赖关系;设计一种深度学习强化方法,解决群体行为最优策略和协同控制方法,并利用混合主动行为选择机制评估学习策略。实验结果表明:作为人机交互实例,所提方法通过深度强化学习使群体全局联合动作表现较好,学习速度和稳定性均能优于确定性策略梯度方法。同时,在跟随、自主和混合主动3种模式比较下,可以较好地控制无人机飞行路径和任务,为无人机集群任务执行提供了智能决策依据。

基于动态优先级的机坪车辆避冲突运行规划方法

【目的】针对机坪车机混行环境,提出了一种考虑动态优先级的避冲突运行规划方法。【方法】首先,从作业效率和运行风险两个层面,提出动态优先级计算方法,完善了多类型保障车辆时变冲突风险划分的规则。其次,考虑保障车辆运行规则和物理特性,建立了考虑行驶和等待时间最小化的混合整数规划模型。最后,设计全局路径优化的两阶段算法进行求解,并通过低时间复杂度的改进冲突探测方法,弥补了传统方法求解大规模复杂问题在时效性方面的不足。【结果】实验表明,设计的算法在大、小规模场景均有较好的适用性,相比对照算法,冲突优化幅度提升7.6%,车辆与航空器冲突占比降低7.5%。【结论】所提方法满足了保障车辆差异化运行要求,实现了车辆和航空器混合运行环境下避冲突路径规划的功能。

“卓越计划”背景下食品质量与安全专业课程SPOC混合教学模式构建和探索

按照“卓越计划”的要求,以食品质量与安全人才培养目标,构筑全新体系课程混合教学模式。针对目前教学模式中存在的问题,利用网络信息平台相结合,构筑了基于小规模限制性在线课程(SPOC)的混合教学模式,并采用多元化的教学方法培养学生的实践能力,线上线下个性化指导,实践时间和空间充足,重点培养学生的动手实践能力及知识的理解,为国家输送高质量工程型人才。