Integrated Control Model for Time and Cost Risk in Project Management

Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems as the delay of schedule by reason of the impracticability of cash flow, the money difficulties caused by delay of schedule and so on. In order to control and manage the time and cost risk effectively and simultaneously, a time & cost risk control model based on schedule programme was established with the use of the quantitativemodels of BCWS, BCWP and ACWP in this paper. Subsequently, the analysis of variance for the whole project and the single activity was introduced on the basis of BCWS, BCWP and ACWP so that the project can be controlled and managed effectively. Furthermore, an example given behind in detail expressly illustrated that the model set up above was practicableto project management. However, the method of optimizing the cash flow based on time and cost risk to obtain BCWS should be considered properlyand carefully with respect to the different circumstances of the project, and an efficient and adequate interval report system should be set up on the site of the project.

Prevalence of-and risk factors for work disability in Dutch patients with inflammatory bowel disease

AIM To determine the prevalence of work disability in inflammatory bowel disease(IBD), and to assess risk factors associated with work disability.METHODS For this retrospective cohort study, we retrieved clinical data from the Dutch IBD Biobank on July 2014, containing electronic patient records of 3388 IBD patients treated in the eight University Medical Centers in the Netherlands. Prevalence of work disability was assessed in 2794 IBD patients and compared with the general Dutch population. Multivariate analyses were performed for work disability(sick leave, partial and full disability) and long-term full work disability(> 80% work disability for > 2 years).RESULTS Prevalence of work disability was higher in Crohn's disease(CD)(29%) and ulcerative colitis(UC)(19%) patients compared to the general Dutch population(7%). In all IBD patients, female sex, a lower education level, and extra-intestinal manifestations, were associated with work disability. In CD patients, an age > 40 years at diagnosis, disease duration > 15 years,smoking, surgical interventions, and anti-TNFα use were associated with work disability. In UC patients, an age > 55 years, and immunomodulator use were associated with work disability. In CD patients, a lower education level(OR = 1.62, 95%CI: 1.02-2.58), and in UC patients, disease complications(OR = 3.39, 95%CI: 1.09-10.58) were associated with long-term full work disability.CONCLUSION The prevalence of work disability in IBD patients is higher than in the general Dutch population. Early assessment of risk factors for work disability is necessary, as work disability is substantial among IBD patients.

Research on Feasibility of Top-Coal Caving Based on Neural Network Technique

Based on the neural network technique, this paper proposes a BP neural network model which integrates geological factors which affect top coal caving in a comprehensive index. The index of top coal caving may be used to forecast the mining cost of working faces, which shows the model’s potential prospect of applications.

Time consumption, productivity, and cost analysis of the motor manual tree felling and processing in the Hyrcanian Forest in Iran

An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran＇s Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis （time study）, we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour （0.17 USD.m^-3 and 0.21 USD-m^-3）, and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m^3 per effective hour and the average unit cost of processing was 0.92 USD.m^-3.

Discrimination and Estimation of the Maximum Cost Performance of Proton Exchange Membrane Fuel Cell Power Generation with Seven Constants

This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation.

煤炭企业安全生产费用效率评价

为评估我国的煤炭企业安全生产费用效率,选用数据包络分析(DEA)方法,选取2012—2020年煤矿安全投入产出数据构建DEA模型,对煤炭企业每年的安全生产费用效率进行静态分析和评价;随后,利用Malmquist指数对煤炭企业安全生产费用效率作进一步动态分析研究。研究结果表明:从静态分析来看,纯技术效率呈负增长趋势是阻碍综合效率增长的主要原因,煤炭企业安全生产费用应占营业收入的4.23%;从动态分析来看,技术进步和技术效率的提高都会相应提高Malmquist指数,提高我国煤炭企业全要素生产率指数的关键是提高技术进步指数。研究结果可为煤炭企业规范使用安全生产费用提供参考。

Fine-Grained Work Element Standardization for Project Effort Estimation

Traditional project effort estimation utilizes development models that span the entire project life cycle and thus culminates estimation errors. This exploratory research is the first attempt to break each project activity down to smaller work elements. There are eight work elements, each of which is being defined and symbolized with visually distinct shape. The purpose is to standardize the operations associated with the development process in the form of a visual symbolic flow map. Hence, developers can streamline their work systematically. Project effort estimation can be determined based on these standard work elements that not only help identify essential cost drivers for estimation, but also reduce latency cost to enhance estimation efficiency. Benefits of the proposed work element scheme are project visibility, better control for immediate pay-off and, in long term management, standardization for software process automation.

执行控制训练对不同工作记忆刷新能力汉英双语者语言控制的影响

通过考察执行控制训练对双语者语言控制的影响,进一步揭示双语者语言控制和执行控制功能的内在联系。采用西蒙箭头任务对不同工作记忆刷新能力的汉英双语者进行执行控制训练,并在训练前后进行语言转换测试。研究发现,与高工作记忆刷新组相比,低工作记忆刷新组在训练后的语言切换代价减小趋势更明显,并在四个月的后测中表现出切换代价减小,而控制组差异不显著。语言转换前后测中,被试从一语切换到二语的反应时均小于二语切换到一语。研究结果表明,执行控制训练对汉英双语者的语言控制具有即时和长期效果,并且双语者的工作记忆刷新能力在执行控制向语言控制的迁移效应中起到调节作用。

考虑成本风险的装备科研激励约束定价设计

带有激励约束机制的装备科研合同定价模式能够较好地适应因科研项目不确定性所带来的成本风险,而激励系数的确定是其中的关键设计。在总结和比较典型的激励约束定价设计的基础上,针对激励系数设计与科研成本风险分析未能有效结合的问题,基于项目工作分解结构(WBS),采用模拟仿真方法得到项目成本概率分布,考虑成本风险大小给出装备科研价格激励约束原则,结合成本概率分布的分位数选择成本上下限,进而确定激励系数和约束系数。同时,还进行了实例分析,结果验证了研究方法的有效性。

龙陵县甘蔗生产机械化发展浅析

甘蔗生产机械化是蔗糖产业发展的趋势,目前人工种植甘蔗需要投入劳动力90人/hm^(2),人工种植成本9150元/hm^(2),而机械化种植成本5437.5元/hm^(2),通过生产机械化开沟、播种、施肥、盖膜一体化操作,可以节约成本3712.5元/hm^(2)。甘蔗机械化作业具有省时、省工、省力,以及延长甘蔗宿根年限和节本增效等优点。甘蔗生产全程机械化的推广应用,不仅是实现乡村振兴、农业现代化的关键,而且是实现蔗农和糖厂利益双赢的必由之路。

基于光电容积脉搏波的心理压力监测系统设计

实时监测人体的心理压力对个人的身心健康发展具有重大意义,而传统心电图法监测心理压力操作复杂且成本较高,为此本文设计了一款基于光电容积脉搏波的心理压力监测系统。首先,采用MAX30101光电传感器采集人体原始脉搏波信号,经db4小波基滤波与基线滤波分析得到心率变异性(HRV)特征;其次,结合BP神经网络对HRV数据集训练得到网络模型,将分析得到的HRV特征输入网络模型评估心理压力;最后,根据压力诱发实验方法设计多组压力测量实验。实验结果表明,测量结果与压力设定参考具有较高的一致性,为心理压力测量提供了一种可行、低成本便携式方案。

浅论控制建筑工程造价的方法

建筑工程造价控制工作作为工程项目顺利开展的基础所在,能够根据项目的实际需求进行成本估算,进而为后续相关工作开展提供有效参考依据。但是在建筑工程造价控制工作开展过程中,仍然存在较多问题,不利于建筑工程项目的顺利开展。在此背景下,本文针对于建筑工程造价控制方法进行深入分析,进而为相关工作开展提供有效参考。

基于定额法和蒙特卡洛模拟的建设项目赶工费用研究

建设项目施工过程中为了实现工期目标而采取赶工措施的现象普遍存在,合同双方在赶工措施方案编制及审批过程中对赶工费用的确定往往存在争议。本文提出基于定额法和蒙特卡洛模拟的建设项目赶工费用的计算方法,即:通过已知工程量及定额确定赶工施工过程所需的人工工日数和机械台班数,通过蒙特卡洛模拟合理确定施工降效系数,得出赶工所需增加的人工工日、机械台班数及人工、机械数量,在此基础上,利用合同工程量清单已确定的人工单价和机械台班费计算出赶工费用,并以浙江某水库工程为例进行赶工费用测算,希望为建设项目确定赶工费用提供参考。

成本管理视角下的建筑工程造价预结算编制准确性研究

为促进建筑工程造价预结算编制准确性的提升,在成本管理视角下,本文开展了对建筑工程造价预结算编制优化研究。通过建立材料价格波动模型、工程量计算误差模型等,实现建筑工程造价预结算编制准确性数学模型分析。结合模型分析结果,提出材料价格对冲策略、优化工程量计算方法、变更管理流程等对策。通过实例论证分析得出,新对策的应用可以有效降低建筑工程造价预结算编制中工程量计算误差率,提高套价符合率,使预结算编制更准确。

盐化工项目安装工程的造价控制初探

轻工行业的盐化工的新建、扩建及改建项目,所涉及到的安装工程中系统分类繁多,品种复杂。特别是近年来许多新技术、新工艺、新材料、新设备在盐化工的应用,对工程安装费造价的控制也带来了新的挑战。本文从已建成的安装工程项目中,对项目实施过程造价控制方面存在的问题,提出了加强工程造价控制的措施与探讨,供同行借鉴。

城际铁路盾构选型研究

针对深惠城际铁路大鹏支线龙坪3号工作井至坪山站区间盾构施工存在穿越中、微风化花岗岩、岩溶和断裂带等不利地质条件以及周边环境复杂等特点和难点,介绍盾构机选型的原则和适用条件,着重从盾构掘进模式、掘进速度、单循环时间、每天进度指标和每月进度指标等方面进行掘进工效测算分析,从人工费、刀具、电力消耗、设备及周转材料摊销等方面进行掘进成本测算分析,结果表明,采用土压/TBM双模盾构代替土压平衡盾构不仅可兼顾复合地层和长距离微风化硬岩地层的掘进需求,在费用及工期方面也更具优势。研究成果可为类似工程提供参考。

工程造价结算审核工作中的问题及对策

当前建筑工程造价结算审核工作中存在一系列问题,包括结算审核制度不完善、审核凭证不足或失真、土方工程结算虚报价款、预算的定额不健全以及结算审核人员综合素养不高等。为解决这些问题,文章提出了一些对策,通过采取这些对策,有望优化建筑工程造价结算审核工作,提高审核的准确性和效率。

强化成本管控提升民营企业并购后项目精细化管理水平

文章在阐述财务精细化管理价值的基础上,结合民营企业经营实际,提出要树立全过程、精细化管理理念,在控制投资成本的基础上,需做好审计阶段的成本控制工作,在管理项目比较成本的同时,需从项目执行、验收及项目后期开展成本管理工作,期望能进一步提升成本管理的精细化水平,拓展企业效益空间,推动民营企业的高质量发展。

概预算编制质量对建筑工程造价的影响分析

为保证建筑工程的稳定发展,施工单位需要重视概预算的编制质量。基于此,文章全面分析了概预算编制质量对建筑工程造价的影响,提出了强化建筑工程概预算编制质量的相关措施,以供参考。

建筑工程造价中的成本控制与效益最大化策略

本文探讨了建筑工程项目中成本控制与效益最大化的策略,重点分析了从项目决策到竣工各阶段的关键措施。基于现代建筑项目成本管理的复杂性和挑战,通过细致的市场调研、成本预测、合同管理以及风险评估等方法,实现了项目成本的有效控制和经济效益的提升。研究结果显示,通过系统的管理措施和现代化工具的应用,不仅能节约成本,还能保证工程质量和进度,为建筑行业提供了实用的成本控制框架。