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1.
An early-warning performance monitoring system (EPMS) is proposed to objectively measure and monitor the performance of a project for early detection of inherent poor performance problems. The EPMS is built based on project progress data and consists of a database of business information, an optimized theoretical model used as a performance measurement baseline, and an index for monitoring and forecasting the performance. By monitoring the performance through an application of the EPMS to the Korean construction project, the quarterly variation of index was found to differ by project type. These results could explain the environmental changes in the project execution. Therefore, the EPMS is expected to be an alternative for objective performance monitoring and forecasting while applying the existing methods is difficult because of the limited available data on performance indicators. The development procedures may also be useful to researchers interested in approaches to quantitatively analyze trends in various industries.  相似文献   
2.
The construction of cybersecurity is an important part of the information construction in university. It is an indispensable condition to help the information construction and a strong guarantee to serve the information support of teachers and students in uni- versity. The cybersecurity environment, atmosphere and guarantee ability of university need to be improved. Based on the related work and achievements of cybersecurity construction, some general schemes are put forward to provide reference for cybersecurity construction in university.  相似文献   
3.
"户外重厨房项目"是一种源于美国科拉多大峡谷大河漂流旅游的营地厨房服务模式,其特点是以物资为基础有效降低户外运动旅行的不舒适性,从而提高参与者评价度,促进旅游者消费。该项目需要在专业建设中囊括体育、旅游相关产业的旅游院校参加,提供一条"旅游+体育+餐饮+酒管"专业人才培养模式,培养复合型旅游人才,以有利于产业的全面、可持续发展以及体育旅游服务质量的提升。  相似文献   
4.
为避免自动泊车过程中出现泊车死区,提出一种在车位外部汽车自动向前行驶至前进水平线的轨迹计算方法;为了减小泊车所需的车位长度,研究了由前进水平线倒车泊入车位,并保证该泊车轨迹经过入位基准线的方法。通过确定出的几个必须经过的定点坐标,利用插值样条理论与几何数学,确定出汽车在车位外部的泊车路径及其函数,且该函数具有唯一性,因此减少了自动泊车过程中系统不断进行反馈与纠正的计算过程。通过实验车的模拟验证,证明了路径规划的正确性。利用CarSim软件进行泊车过程的运动仿真,并对绘制出的轨迹线进行分析,结果表明该方法能控制汽车自动前进至非泊车死区位置,并可以减少对泊车所需车位长度的要求。  相似文献   
5.
Firebrand production from structure combustion becomes a key factor in the magnitude of how quickly a large outdoor fire may spread. Post‐fire disaster investigations suggest that attached building components, such as wood fencing assemblies are known to be prone to ignition in these fires, and may provide pathways to structure ignition. Here, a comparison of ignition results from full‐scale fencing assembly experiments conducted using a full‐scale wind tunnel facility, to mock‐ups of full‐scale fencing assemblies using the recently developed experimental capability at the National Research Institute of Fire and Disaster (NRIFD) are discussed. In both experimental facilities, the fencing assemblies were exposed to firebrand showers using custom built continuous feed firebrand generators with size and mass distributions similar to those generated from structure combustion. Similar ignition behaviors were observed between the full‐scale fencing assemblies and the mock‐up of full‐scale fencing assemblies. Additional experiments are required for other fencing assembly types to further verify these important findings.  相似文献   
6.
Xilei Dai  Junjie Liu  Yongle Li 《Indoor air》2021,31(4):1228-1237
Due to the severe outdoor PM2.5 pollution in China, many people have installed air-cleaning systems in homes. To make the systems run automatically and intelligently, we developed a recurrent neural network (RNN) that uses historical data to predict the future indoor PM2.5 concentration. The RNN architecture includes an autoencoder and a recurrent part. We used data measured in an apartment over the course of an entire year to train and test the RNN. The data include indoor/outdoor PM2.5 concentration, environmental parameters and time of day. By comparing three different input strategies, we found that a strategy employing historical PM2.5 and time of day as inputs performed best. With this strategy, the model can be applied to predict the relatively stable trend of indoor PM2.5 concentration in advance. When the input length is 2 h and the prediction horizon is 30 min, the median prediction error is 8.3 µg/m3 for the whole test set. For times with indoor PM2.5 concentrations between (20,50] µg/m3 and (50,100] µg/m3, the median prediction error is 8.3 and 9.2 µg/m3, respectively. The low prediction error between the ground-truth and predicted values shows that the RNN can predict indoor PM2.5 concentrations with satisfactory performance.  相似文献   
7.
起重机械作为工业发展的基础性产业,其安全使用一直备受关注,有关的检测技术和手段日新月异。文中结合起重机械检验检测工作特点和流程,基于目前日趋成熟的移动实验室技术,提出了起重机械移动综合检测平台的设计方案。对现有检测手段、业务流程、办公软件、网络系统等进行整合,将检测平台结构分为车载基础和业务测试2个功能模块,实现了起重机械一站式的业务服务、检验检测、远程联检等功能,推进检验检测工作提质增效,并具有一定的扩展性,为智慧特检提供了一种思路。  相似文献   
8.
为满足人们对春秋季户外休闲运动服装的需求,采用藏青羊毛纱、白色羊毛纱、涤纶丝以及锦纶丝为原料,在双面电脑提花机上开发4款羊毛针织面料,并选择2款规格相近的高密度面料作为对比样。对6种面料的耐磨性、顶破强力、抗起毛起球性、透气量、悬垂系数、克罗值、液态水分管理能力进行测试分析,采用模糊综合评价方法对面料的服用舒适性能进行评价,最后选出服用性能最好的羊毛针织面料,为羊毛户外休闲运动针织面料的开发提供参考。  相似文献   
9.
The Global Positioning System (GPS) offers the interferometer for attitude determination by processing the carrier phase observables. By using carrier phase observables, the relative positioning is obtained in centimeter level. GPS interferometry has been firstly used in precise static relative positioning, and thereafter in kinematic positioning. The carrier phase differential GPS based on interferometer principles can solve for the antenna baseline vector, defined as the vector between the antenna designated master and one of the slave antennas, connected to a rigid body. Determining the unknown baseline vectors between the antennas sits at the heart of GPS-based attitude determination. The conventional solution of the baseline vectors based on least-squares approach is inherently noisy, which results in the noisy attitude solutions. In this article, the complementary Kalman filter (CKF) is employed for solving the baseline vector in the attitude determination mechanism to improve the performance, where the receiversatellite double differenced observable was utilized as the measurement. By using the carrier phase observables, the relative positioning is obtained in centimeter level. Employing the CKF provides several advantages, such as accuracy improvement, reliability enhancement, and real-time assurance. Simulation results based on the conventional method where the least-squares approach is involved, and the proposed method where the CKF is involved are compared and discussed.  相似文献   
10.
Most of human exposure to atmospheric pollutants occurs indoors, and the components of outdoor aerosols may have been changed in the way before reaching indoor spaces. Here we conducted real-time online measurements of mass concentrations and chemical composition of black carbon and the non-refractory species in PM2.5 in an occupied office for approximately one month. The open-close windows and controlled dampness experiments were also performed. Our results show that indoor aerosol species primarily originate from outdoors with indoor/outdoor ratio of these species typically less than unity except for certain organic aerosol (OA) factors. All aerosol species went through filtration upon transport indoors. Ammonium nitrate and fossil fuel OA underwent evaporation or particle-to-gas partitioning, while less oxidized secondary OA (SOA) underwent secondary formation and cooking OA might have indoor sources. With higher particulate matter (PM) mass concentration outdoors than in the office, elevated natural ventilation increased PM exposure indoors and this increased exposure was prolonged when outdoor PM was scavenged. We found that increasing humidity in the office led to higher indoor PM mass concentration particularly more oxidized SOA. Overall, our results highlight that indoor exposure of occupants is substantially different from outdoor in terms of mass concentrations and chemical species.  相似文献   
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