Investigation of Pile Construction and Productivity Loss: An Analysis of Macro Impact Factor

Pile foundations are challenging to build due to subsurface obstacles, contractor ignorance, and difficulties with site planning. Given the unpredictable environment of the construction site, productivity losses during pile work are to be thought possible. Prior to finishing a site pre-investigation, a foundation’s area is usually sampled for statistical reasons. There are studies on pile construction outside of Bangladesh that are supported by relevant empirical data in the literature. Since Bangladesh, which is regarded as a third-world country, is ignored in this regard, the literature currently available about pile building and the associated productivity loss is unable to provide adequate information or appropriate empirical data. Due to this pile-building sector in Bangladesh has been experiencing a decline in production for quite some time now. Before attempting to increase productivity in pile construction, it is essential to investigate the potential losses and the variables that might have an influence. This study aims to accomplish the following objectives: 1) identify the primary factors that have an impact on pile construction;2) develop an SVR model that accurately predicts productivity loss;and 3) figure out the projected loss by basing it on the historical scenario that is the most comparable to the current one. A Support Vector Regression (SVR) model was developed after a study of the relevant literature. This model enabled the collection of 110 pile building projects from five significant locations in Bangladesh. The model was constructed using a list of eight inputs in addition to a list of five macro elements (labor, management, environment, material, and equipment) (soil condition, pile type, pile material, project size, project location, pile depth, pile quantity, and equipment quantity). Using 10-way cross validation, the SVR achieves an accuracy of 87.2% in its predictions. On the basis of what has occurred in the past, we are able to estimate that there will be a loss of around 18.55 percent of the total output. A new perspective for engineers studying the delay factors with productivity loss is provided by the outcome of important tasks as it relates to loss in productivity and overall factors faced. In the building construction industry, effective management should place more emphasis on the correlation between productivity loss and the factors that cause it. Therefore, to represent the effect on productivity loss, real factors can be summed up as a decline in productivity loss. The findings of the study would urge specialists to concentrate on waste as a means of increasing overall production.

Occupational Heat Stress in the Floriculture Industry of Ethiopia: Health Risks and Productivity Losses

Background: The Ethiopian flower industry is growing fast with successful diversification of export products under greenhouse structures. Higher temperatures in the greenhouses pose a serious threat to the health of workers and add to the risk of occupational heat stress. Excessive heat in workplace settings also reduces work capacity and labour productivity. This study aims to investigate the level of heat exposure, and workers’ and managers’ perceptions and behavioural responses towards extreme heat exposure in a warming climate. Methods: We used the Wet Bulb Globe Temperature (WBGT) measured in representative greenhouses to capture the heat exposure during hotter and cooler seasons following ISO 7243 (generally risk of heat stress occurs when WBGT exceeds 26°C). A comparative cross-sectional study design with a stratified sampling method was used to assess occupational heat stress and workers’ perceptions of the impact of heat on their health and productivity in six different floriculture greenhouses in Ethiopia representing three different agro-ecologies and products. A questionnaire survey was conducted (30 managers/supervisors and 305 workers;76.1% female) to capture perceptions on heat exposures, symptoms of potential health impacts, productivity losses and coping mechanisms. Results: Heat exposure varied across different agroecologies, product types and greenhouse materials with a median WBGT Index of 25.5°C and a range from 18.1°C to 31.5°C. The impact of heat stress also varied across different employment sectors and geographical regions. Overall, workers in cut-flower greenhouses are exposed to higher than recommended WBGT Index (26°C) for 3 - 6 working hours daily. 65% of the managers reported that heat stress has a significant impact on the workers’ labour productivity, but do not have guidance about working in hot conditions. Workers reported more heat-related health issues and reduced productivity, especially in the mid-altitude greenhouses. About 50% of the workers reported that heat exposure decreased work productivity during hot hours. Sweating, exhaustion, heat-rashes, dehydration, crumps, nausea and headache were self-reported health issues. Labour productivity losses ranged from no loss to 19.5% in the mid- and low-altitudes. Conclusions and Recommendations: Excessive workplace heat in the greenhouses is both an occupational health hazard and detrimental to productivity in the floriculture industry. However, the level of understanding and actions on the ground regarding occupational heat stress are low. The code of conduct in place now does not consider the occupational heat stress issues. Multiple actions (engineering, management, training and policy-related recommendations) have to be implemented by Ethiopian Horticultural Producers and Exporters Association (EHPEA) and farm owners to mitigate heat stress and loss of productivity. Designing and implementing these heat prevention strategies and incorporating them into the code of conduct is in the interests of both employers and employees.

Repeated pregnancy losses with multiple aneuploidies and major genomic imbalance:A case report

Rationale:If one of the partners is having balanced autosomal translocation,it is usually observed that the offspring inherit either normal chromosomes,balanced translocation identical to one of the parent or unbalanced chromosomal rearrangements of the same parental chromosome having translocation.Concern:A unique case presented with history of 8 miscarriages for genetic counseling.The last abortus material evaluation showed monosomy of chromosome X(Turner syndrome)in all the analyzed cells.There was a history of infertility and also repeated second trimester abortions on the paternal side.On the maternal side,there was a history of intellectual disability.Diagnose:History of repeated abnormal pregnancy outcomes.Wife’s karyotype is normal;however,husband shows translocation between chromosome 4 and 22.Intervention:Peripheral blood sample around 3 mL was collected for karyotype.Embryo biopsy was done and DNA was extracted and processed for whole exome sequencing.Outcomes:Wife’s karyotype is normal and husband has translocation between chromosome 4 and 22.Surprisingly,the entire pregnancy outcome including embryo screening has different,complete or partial aneuploidies of chromosomes other than chromosome 4 and 22.Main lesson:Though the translocation in one of the parent is balanced,we have to think beyond traditional ways for evaluating a couple with repeated pregnancy loss as we cannot predict the errors at cell division.Option of in vitro fertilization and preimplantation genetic diagnosis in couples having balanced translocations should be discussed so that early intervention can prevent the agony of pregnancy loss.

Effect of acidic deposition on productivity of forest ecosystem and estimation of its economic losses in southern suburbs of Chongqing, China

In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern suburbs of Chongqing, China were studied. Based on the field data and measurements, a multivariable stepwise regression model was established to analyze the effects of multiple environmental factors on the productivity of the forest ecosystems. This model was used to assess the volume and economic losses of these two forest ecosystems caused by acidic deposition. The result showed that, among the environmental factors, pH value of precipitation, soil depth, soil organic contents and slope are the dominant ones influencing the growth of masson pine forest. It was also shown that the acidic deposition has no clear relation to the growth of C.Campora forest, so development of such broad leaved forest is suitable in the area.

The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems

Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production.

Constraining the colored cc energy loss from J/Ψ production in p-A collisions

Considering the volatility of the propagation path for charmonium passing across the nuclear target in J/ψ formation from p-A collisions, the charmonium energy loss is investigated using Salgado-Wiedemann quenching weights. A successful description regarding J/ψsuppression of R_(w(Fe)/Be)(x_F) from the E866 experiment for 0.2 <x_F<0.65 gives the transport coefficient q = 0.29 ± 0.07 GeV^2/fm for the colored cc energy loss.The calculated result indicates that radiative energy loss of a parton should be independent of its mass at high energy.The calculations are further compared to LHC and RHIC measurements.

Earthquake loss estimation by using Gross Domestic Product and population data

In the traditional method of earthquake loss estimation, all the social wealthes are classified according to their structural type and occupational use. Inventory data is collected and the total loss is estimated from each facility class separately. For many regions of the world, however, the vast amount of data required by this method is difficult or impossible to obtain. The traditional method is also unable to estimate quickly the loss from an unexpected disaster earthquake. It is difficult to give the necessary risk information to help the government to rescue and relief the earthquake disaster. This paper proposes a simple estimation method of earthquake loss based on macroscopic economical index of Gross Domestic Product (GDP) and population distribution data. A preliminary nonlinear relation among hazard loss, seismic intensity and social wealth was developed by means of some earthquake disaster records during 1980～1995. This method was applied to analyze several assumed earthquakes. The preliminary analysis results show that the new method is effective and reasonable for quick assessment of earthquake loss.

Relation between oxidation microstructure and the maximum energy product loss of a Sm_2Co_(17) magnet oxidized at 500℃

The oxidation microstructure and maximum energy product （BH）max loss of a 8m（Co0.76, Fe0.1, Cu0.1, Zr0.04）7 magnet oxidized at 500 ℃ were systematically investigated. Three different oxidation regions were formed in the oxidized magnet： a continuous externM oxide scale, an internal reaction layer, and a diffusion zone. Both room-temperature and high-temperature （BH）max losses exhibited the same parabolic increase with oxidation time. An oxygen diffusion model was proposed to simulate the dependence of （BH）max loss on oxidation time. It is found that the external oxide scale has little effect on the （BH）max loss, and both the internal reaction layer and diffusion zone result in the （BH）max loss. Moreover, the diffusion zone leads to more （BH）max loss than the internal reaction layer. The values of the oxidation rate constant k for internal reaction layer and oxygen diffusion coefficient D for diffusion zone were obtained, which are about 1.91×10^-10 cm^2/s and 6.54×10^-11 cm^2/s, respectively.

Multi-objective optimization design of deviation-correction trajectory considering the production loss in shale gas cluster well

In shale gas mining,the inter-fracture interference effect will significantly occur if the actual well deviates from the planned trajectory.To reduce production loss,operators want to get back on the planned trajectory economically and safely.Based on this,a multi-objective optimization model of deviationcorrection trajectory is established considering the production loss evaluation.Firstly,the functional relationship between the production envelope and the fracturing depth is constructed,and the production loss is obtained by combining the calculation method of volume flow.Based on the proposed“double-arc”trajectory design method,the production loss of the fracture on the deviation-correction trajectory is obtained.Finally,combined with the well profile energy evaluation,a new optimization model of deviation-correction trajectory is established.The results demonstrate that after optimizing the fracturing depth,the production loss of the deviation-correction trajectory is reduced by 13.2%.The maximum curvature value results in a trajectory with a minimum production loss yet a maximum well profile energy.The proposed model reduces the well profile energy by 15.6%compared with the existing model.It is proved that the proposed model can reduce the probability of drilling accidents and achieve high gas production in the later mining stage.This study fully considers various factors affecting horizontal wells in the fracturing area,which can provide theoretical guidance for the design of deviationcorrection trajectory.

Decomposition of China＇s Industrial Environmental Total Factor Productivity Sources： Analysis Based on Factor Input and Pollution Treatment

Following slack-based inefficiency measurement method and Luenberger productivity index, this paper decomposes industrial environmental TFP index by input factors and output to estimate the sources of China＇s industrial environmental TFP. Results indicate that （1） China＇s industrial environmental TFP increased between 2001 and 2007 but declined in 2008 under the effect of global financial crisis; （2） input utilization productivity contributes 1/3 to industrial environmental TFP and pollution treatment productivity contributes about 2/3, which means that pollution treatment will effectively increase industrial environmental TFP; （3） capital utilization productivity contributes I/6 to input productivity and labor utilization productivity contributes about 5/6, which means that progress of labor production technologies is an effective means to increase industrial environmental TFP; （4） COD treatment productivity contributes roughly 2/3 to pollution treatment productivity, and S02 treatment productivity contributes about 1/3, which shows that priority on COD treatment will more effectively increase industrial environmental TFP.

基于产量损失率的气井合理配产方法研究

合理配产对气井生产具有非常重要的作用。现有的配产方法一般是按照无阻流量的1/6∼1/3来进行。在研究气体在地层中的非达西效应的基础上,提出了产量损失率的概念,通过量化非达西效应造成的产量损失,建立了气井产量损失率与无因次产量的图版。对于每一个配产,可得到与其相应的产量损失率,非达西效应对气井产量的影响就有了定量化的表征。因此,可根据产量损失率来进行合理配产。对于某些高压气藏,由于地层压力高,气体压缩程度大,地层条件下非达西效应并不强,产量损失率比较低,这类气井就可以将产量配高一些。该配产方法可实现量化储层气体非达西渗流损失,实现气井合理配产。该研究成果能在气井常规配产方法的基础上,进一步优化气井配产制度,更好地满足气井长期稳产、高效开发的需求,为气藏开发提供有益的借鉴。

基于用户生产场景辨识的电压暂降经济损失评估

准确评估工业用户电压暂降经济损失,是制定治理方案、估算赔偿金额的前提。针对现有评估方法未考虑实际生产场景多变、先验数据有限的问题,提出了考虑用户生产场景变化的电压暂降经济损失评估方法。首先,基于奇异值分解以及K最邻近算法检测过渡区间,进行功率数据分段,并构建功率数据特征指标体系,准确刻画功率数据特性;其次,提出基于改进生成对抗网络(generative adversarial networks,GAN)的数据增强模型,通过引入特征损失提高生成数据质量并保证多样性,解决先验数据有限问题;再次,混合生成数据及先验数据,构建用户生产场景辨识模型,实现用户生产场景的有效辨识;最后,根据电压暂降发生时刻的生产场景明确生产线运行状态,结合各生产场景下的工业过程中断次数及生产线中断损失,实现电压暂降经济损失的准确评估。通过算例验证了该文方法的有效性和准确性。

基于熵产理论的管道泵流动损失特性分析

为了揭示管道泵运行过程中的流动损失特性,基于熵产理论,采用数值计算方法对管道泵吸水室和叶轮内的总熵产以及局部熵产率进行了研究,并结合压力脉动及涡核分布对其产生流动损失的原因进行了分析。研究结果表明,叶轮总熵产和吸水室总熵产保持高度一致性,吸水室内部流动影响了叶轮内部流动。随着流量的增大,叶轮和吸水室总熵产先减小,随后增大,这与其内部监测点的压力脉动主频幅值变化规律基本一致。叶轮总熵产显著大于吸水室总熵产,偏工况下更为明显,前者至少是后者的4倍。湍流耗散熵产占据吸水室和叶轮总熵产的90%以上,构成了流动损失的主要部分。吸水室高熵产率区主要分布在第二弯道及出口处,小流量工况下的熵产率是其余工况下的数百倍,该位置的大尺度带核涡以及附壁涡是导致熵产率增加的主要原因。叶轮高熵产率区主要集中在叶轮进口和出口,在大部分区域,小流量下的熵产率是其余工况的6倍以上,小流量工况下叶轮进口预旋和出口失速涡以及大流量工况下叶轮中上游的分离涡是导致熵产率较高的主要原因。该研究可为管道泵局部流动损失识别以及开展针对性优化提供参考。

冻融环境下钢渣细骨料混凝土微观结构及损伤演化模型

为了揭示工业钢渣细骨料制备的钢渣混凝土的冻融破坏机理,采用快速冻融法进行试验,测试了冻融循环后不同钢渣细骨料替代率混凝土的质量损失率、强度损失率、相对动弹性模量,并分析冻融损伤规律;使用扫描电镜方法观察钢渣混凝土水化产物及钢渣-砂浆界面过渡区,进行冻融损伤微观机理的分析。结果表明:钢渣细骨料因冻融作用而发生明显破坏;钢渣细骨料与水泥凝胶的界面过渡区优于普通骨料;钢渣替代率为60%时混凝土的质量、强度损失最小,分别只减少了4.06%、44.2%;钢渣替代率为100%时混凝土的质量、强度损失率最高,分别为6.05%、58%;冻融循环次数大于50时,钢渣掺量为60%的混凝土相对动弹性模量高于其余掺量组;采用钢渣取代细骨料为提高混凝土在冻融循环作用下的工作性能时建议取代率为60%。通过对钢渣混凝土的损伤演变分析,建立了钢渣混凝土的冻融损伤演变模型。

基于多源数据的全国三大主粮生产风险评估研究

【目的】“一省、一作物、一费率”的粗放式定价模式带来逆选择、道德风险、经营乱象等问题,严重制约我国农业保险的健康可持续发展。费率定价离不开风险评估,开展全国三大主粮生产风险评估、制作风险地图,为实现我国主粮保险费率精准化、推进主粮保险高质量发展提供依据。【方法】围绕我国三大主粮作物(水稻、小麦、玉米),收集整理长时间序列的三大风险数据源(单产、灾情和保险数据),以单产数据为核心,结合灾情数据和保险数据,开展基于多源数据的风险评估建模,通过县级风险的低估调整和省级风险的秩相关调整,计算全国三大主粮省级和县级的纯风险损失率,采用分位数法开展全国三大主粮风险分区,制作风险地图。【结果】省级风险的秩相关调整以灾情风险结果为主,保险风险结果为次。经调整,水稻秩相关系数由0.610提升到0.766,小麦由0.547提升到0.748,玉米由0.576提升到0.760。调整后,全国三大主粮平均的风险低估系数为20%—40%,说明全国范围内利用县域单产开展风险评估的平均低估程度在2—4成,玉米低估系数要高于水稻和小麦。从省级尺度上看,黑龙江三大主粮生产风险均处于极高水平,内蒙古水稻、小麦,吉林和辽宁水稻、玉米生产风险处于极高水平,山西小麦生产风险处于极高水平;从县级尺度上看,水稻生产的极高风险(纯风险损失率>4.4%)主要集中在东北三省绝大部分种植县域、内蒙古东北部与东北三省接壤的种植县域。小麦生产的极高风险(纯风险损失率>6.3%)主要集中在内蒙古绝大部分种植县域。玉米生产的极高风险(纯风险损失率>6.9%)主要集中在内蒙古与东北三省、山西和陕西接壤的种植县域,辽宁、安徽、江西的大部分种植县域。从全国833个产粮大县上看,玉米极高和高风险县域数量占比最高(28.1%),水稻次之(25.1%),小麦最低(17.2%),说明玉米整体风险水平较高,小麦最低。【结论】研究揭示了我国三大主粮作物生产风险大小与空间差异。从全国平均水平上看,玉米风险最大(平均纯风险损失率为5.0%)、小麦次之(3.1%)、水稻最小(2.6%);从空间差异上看,东北和中南地区水稻风险较高,华北和华东地区小麦风险较高,华北、东北和华东地区玉米风险较高。水稻、小麦和玉米其他级别风险的空间差异特征也不一致。

生产建设项目人为水土流失风险与分类监管的响应——以武汉市为例

未来一段时期,我国开发建设强度仍将维持在较高水平,人为水土流失防治及监管任重道远。为实现人为水土流失分类分级及差别化管控,开展生产建设项目人为水土流失风险评估与分类监管研究非常迫切。基于以往研究成果,结合实践经验,定性和定量相结合,提出生产建设项目人为水土流失风险评估方法,即在建项目采取潜在水土流失风险评估与水土保持现状评价综合确定风险等级,完工项目则只需根据水土保持现状评价结果确定风险等级。以武汉市为例,对市本级117个生产建设项目进行人为水土流失风险评估。结果显示,武汉市生产建设项目以无风险等级为主,占项目总数的66.7%;其次为低风险等级,占项目总数的25.6%;中、高和极高风险等级分别仅占项目总数的2.6%、1.7%和3.4%。经典型案例分析,评估结果与实际较相符,证明评估方法科学可行。在此基础上,按照“无风险不打扰、低风险预提醒、中高风险严监控”总体要求,结合项目管理的其他需求,提出武汉市本级生产建设项目差别化分类监管的具体建议。

江汉水牛生产性能及经济效益研究

[目的]研究江汉水牛的主要体尺指标和生产性能,为江汉水牛保种和开发利用提供理论依据。[方法]测定20头2.5岁左右、平均体质量(360±59)kg江汉水牛(公牛10头、母牛10头)的主要体尺指标,并进行134d的强度育肥试验。育肥结束后,选取12头江汉水牛(公牛6头、母牛6头)进行屠宰和肉质性能测定。[结果]江汉水牛育肥期平均日增质量为(818±189) g,平均日采食量为26.87 kg。江汉水牛屠宰率为45.4%,净肉率37.6%,眼肌面积85.7 cm^(2),肌肉嫩度平均为80.35 kg/cm^(2),肌肉肉色评分7.83,滴水损失1.17%,江汉水牛产肉成本为27.57元/kg。[结论]江汉水牛躯体高大,骨骼粗壮,肉质优良,是培育乳肉兼用水牛新品种的良好遗传素材。

一种基于液位仪系统的加油站V_(20)油品损溢考核简便算法

依据多年实践和管理经验,利用现有的液位仪系统数据,摸索出一种基于液位仪系统的加油站V_(20)油品损溢考核简便算法,可以快速简便地计算出被管理单元(加油站、县公司、市公司等)的V_(20)油品损溢率,特别是对油品进销存过程中温度变化较大的加油站,能够剔除掉“虚假损耗”的影响,相对真实地还原被管理单元的损溢管理水平,为科学、公正的管理和考核提供了有力的数据支撑。

地热井用两级潜水泵内流熵产诊断及水力性能优化

为了提升地热井用潜水泵的运行效率,根据地热井用潜水泵的流动参数和实际运行工况,完成了两级潜水泵过流部件水力设计,并进行了全流道流动数值模拟和试验验证;采用熵产分析法定位了潜水泵内流场的高能耗区域,主要集中在级间交汇和动静部件干涉处;采用正交设计和结构参数敏感性分析方法,确定了结构参数对潜水泵性能的影响规律,以叶轮叶片出口角、出口宽度、叶片包角和导叶轴向长度为优化变量,以扬程和效率为优化目标,通过遗传算法、最优拉丁超立方采样和熵权TOPSIS法对两级潜水泵进行水力优化。结果表明,额定工况下,优化泵的扬程增加了24.9%,效率增加了5.7%,总水力损失减小了1024.9 W,高能耗区域明显降低,水力性能显著提升,分离流、二次回流和冲击流动等不良流动得到显著抑制;大流量工况处理能力大幅度提升,高效区间范围扩大了70%,运行稳定性得到显著提高。研究内容为潜水泵的设计及内流场研究提供理论指导。

对旋轴流通风机叶轮内不可逆能量损失机理

随着节能降耗成为当今世界的迫切需要,提高通风机能量转换效率越来越受到重视,已成为通风领域内关键问题。掌握叶轮内不可逆能量损失演化机制是实现能量高效转化的前提与基础,但目前尚缺乏针对叶轮内不可逆能量损失机理方面的研究。为此,以对旋轴流通风机为研究对象,采用数值模拟和实验方法获得了不同流量工况下通风机内部流场。基于熵产理论,建立了通风机叶轮内不可逆能量损失理论模型,明确了叶轮内不可逆能量损失与空间流场参数的内在关系,实现了叶轮内不同类型能量损失的定量分析,结合叶轮内流动特征,明确了能量损失空间演化规律和产生原因。研究结果表明,熵产方法计算叶轮内不可逆能量损失是可靠的,直接黏性耗散损失和壁面摩擦损失是能量损失的重要组成部分,而湍流耗散则是引起能量损失的主要原因,达到总能量损失的60%~80%;对于前级叶轮,湍流耗散引起的能量损失在1.0Q_(BEP)流量工况(Q_(BEP)为最优工况流量)达到最小,而后级叶轮能量损失随流量的降低而增大。能量损失主要集中在Span=0.6~1.0(Span为叶展方向轮毂至机壳的无量纲距离)区域,在1.0Q_(BEP)工况达到总能量损失的70%;叶顶间隙泄漏流和叶片前缘溢流引起的螺旋旋涡、叶轮内回流、叶片压力面和吸力面流动分离以及叶片后缘尾迹都将导致能量损失产生,其中流动分离和尾迹引起的高能量损失区域较小,能量损失相对有限,而旋涡和回流显著影响叶轮内流体流动,最终导致叶顶附近区域出现大量能量损失。