Four severe nuclear accident scenarios have been identified for operating nuclear power plants (ONPPs). However, there is a research gap in predicting the mid–long-term radiation doses for these scenarios. This study aims to address this gap by proposing a novel approach for predicting the mid–long-term radiation dose in the case of a hypothetical short-term station blackout (STSBO) scenario, one of the aforementioned scenarios. Firstly, the Weather Research and Forecasting (WRF) model was coupled with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) (WRF-HYSPLIT) model to establish an atmospheric transport and diffusion model for airborne radionuclides, and the regularity of the atmospheric transport and diffusion for the airborne radionuclides was determined. Subsequently, the Residual Radioactive Material Guidelines (RESRAD) OFFSITE (RESRAD-OFFSITE) code was utilized to establish a radiation dose model for predicting the mid–long-term radiation dose resulting from the airborne radionuclides, and the evolution of the mid–long-term radiation dose was analyzed. Finally, the proposed approach was applied to an ONPP, and the results were used to predict the mid–long-term public radiation dose. The results indicated that the total radiation dose would be lower than the dose limit recommended by the International Commission on Radiological Protection (1 mSv/yr) from the second month to the 100th year after the hypothetical STSBO nuclear accident, and the total radiation dose would decrease slowly over time. Recommendations are made for offsite emergency response measures. These research findings can assist ONPPs in analyzing their environmental impacts in the event of an STSBO scenario.

This study proposes an approach for simultaneously treating fuzziness and randomness when conducting safety risk assessments of nuclear power plant building projects (NPPBPs). First, the interval type-2 fuzzy set (IT2FS) and analytic network process (ANP) were employed to establish an IT2FS-ANP method for modifying the solution for the weight vector and determining the mutual relationships between the assessment indexes and their weights. Second, the IT2FS and cloud model (CM) were used to establish the IT2FS-CM method to modify the solution for the expectation value. Third, the IT2FS-ANP and IT2FS-CM methods were combined to establish a model for ranking the safety risks and determining the overall safety risk level. Finally, the approach was applied to an NPPBP in northeast China to validate its applicability.

In view of the problem of high temperature and strong radiation in the vertical fluorination furnace for producing uranium hexafluoride in a factory, this paper combined the specific process flow, based on the existing heat insulation wall, designed the exhaust heat insulation cover combining the upper suction cover and the heat insulation wall,and simulated and optimized the model structure by CFD software, aiming at reducing the heat loss of the furnace body and the thermal impact on the environment on the premise of controlling the diffusion of aerosol and thermal pollution. By optimizing the thickness of the interlayer of circulating air, and comparing the applicability of different structures of walls in this study, finally, the thermal insulation wall structure was optimized, and the thermal resistance of the wall was improved.

就目前国内外洁净室压差控制的研究现状作一文献综述,重点介绍了影响洁净室内压差控制的三个因素及其控制策略.然后,结合文献的研究结论分析现有的洁净工程在调试以及运行中所发现的压差控制问题并加以讨论,确定了未来可能的研究内容.

液体循环热回收系统是空调排风热回收系统的一种形式,可以从排风中回收能量从而减小新风能耗,广泛应用于高档酒店、医院建筑和洁净生产车间.本文介绍了液体循环热回收系统的工作原理,对系统性能评价指标和计算方法进行讨论,针对该系统在设计和运行过程中存在的问题进行了探讨,并提出解决方法,还分析了该系统的应用前景.提出可以从静态参数优化与动态计算结合、空调工况分区焓湿图与系统能效比结合、大数据分析等方面研究该系统的高效运行方法和精准控制策略.

为了降低洁净室全新风空调系统的能耗,基于深圳某生物医药洁净车间的液体循环热回收系统,采用效能-传热单元数法建立盘管数学模型,模拟系统性能参数,并设计正交试验分析因素主次和优方案,最后提出一种加强换热的措施.研究结果表明:水流量在2.5kg/s时,盘管换热量达到峰值.室外温湿度增加,热回收量最大增幅88％,室内温湿度增加,热回收量最大减幅14％.通过正交试验结果表明:影响热回收量的因素主次为水流量、室外温度、室内温度、室外相对湿度、室内相对湿度,优方案为水流量3.5kg/s,室内温度24℃,室内相对湿度50％.加强换热后系统总体节能20kW.

阐述一流本科教育建设内涵意义,分析地方高校教育教学质量评价体系现状及问题,有针对性地从完善质量评价体系的设计、增强评价指标的科学性、采取多样化的评价方法以及增强评价信息及时反馈功能等四个方面提出了相应策略.

建筑电气与智能化专业是一个具有多学科交叉特色的新工科专业,专业课程涉及土木类、电气工程类和信息工程类等学科,兼顾各课程学时安排,合理规划课程培养目标,有力支撑毕业达成指标,最终建立科学合理的课程体系,是通过工程教育认证的重要保障.该文以南华大学建筑电气与智能化专业为例,探讨基于工程教育认证的专业课程体系建设思路.

建设一流本科教育、创建一流本科专业,是新时期地方高校强化内涵发展、提升自身竞争力、服务区域经济的必然选择.南华大学在60余年办学历程中,高度重视一流本科专业建设与发展,逐步明晰和确立了学校本科专业建设的发展目标与优势,并积极推进一流本科专业建设的理论与实践探索,在增强学校核心竞争力、优化学科专业体系、提高教师整体素质以及全面提升人才培养质量等方面取得了显著的成效.

研究喷气增焓复叠式热泵系统,首先介绍其工作原理,然后根据其工作原理搭建实验样机.设计的喷气增焓复叠式空气源热泵系统可以单级运行制热,也可以两级复叠式运行制热.使用喷气增焓复叠式空气源热泵系统和实验测试系统,通过改变环境工况测试系统运行性能.结果表明,环境温度从-15℃上升至15℃时,单级运行系统制热量增加38.19％,功率降低32.64％,COP从2.21上升到4.54;复叠运行时随着压缩机频率增加,系统COP先增加后减小,系统存在最佳频率,同时系统排气温度增加.研发新型空气源热泵供暖取代传统煤炭取暖,解决传统空气源热泵在北方冬季低温环境中运行效率低、稳定性差的问题,使得空气源热泵能在北方地区推广具有重要的节能减排和绿色环保意义.

针对厂房内高温热源散发的热量向工作区域扩散的问题,设计出一种基于厂房高温热源的隔热降温墙体.研究了管路中心距、空腔厚度、保温层厚度对该墙体隔热降温性能的影响,采用正交试验设计的方法设计了上述结构参数的9个组合方案,利用CFD数值模拟的方法对每个组合方案下墙体的隔热降温性能进行了模拟.研究结果表明:以墙外侧壁面温度和墙体供冷量作为评价指标,分别对模拟结果进行极差分析和方差分析,得到两种分析方法结果具有一致性,并在分析中可知各因素对墙体性能影响的显著程度,最终得到最优结构方案:管路中心距100 mm,空腔厚度60 mm,保温层厚度30 mm,该研究大大减少了试验或模拟工作量,提高了模型结构优化效率和性能分析速度,为外围护结构的节能设计提供了新的思路和方法.

在建环专业实习受制于经费、时间、场地等因素制约而不能达到其预期教学效果的背景下,构建专业实习网络教学平台,为学生提供基于慕课教学模式的"预演式学习"是解决问题的基本思路.结合本专业不同实习阶段所需的知识储备和实习内容,构建了"预演式学习"教学平台内容框架.结合网络课程线上学习的需求,进行了"预演式学习"教学平台板块设计.随着建环专业实习网络教学平台内容的不断改进与完善,可以有效提升教学效果.

为防止厂房内高温热源的热量向工作区域的扩散,提出一种新式的用于厂房高温热源的通风供冷墙体.采用Fluent软件分别模拟了供水参数、送风速度、环境温度、空腔厚度等对墙体隔热降温性能的影响,最后研究得出夏季工况下不同因素对通风供冷墙体单位面积供冷量,外墙温度和散热量的变化规律,为外围护结构的节能设计提供了新的思路和方法.

以湖南省某大中型综合医院能耗占比最大的病房楼的25个科室为样本,使用SPSS软件对科室能耗的9个能耗影响因素进行了相关性分析,结果表明:科室建筑面积和年床日数是能耗的主要影响因素.按照湖南省地方标准对医院能耗水平进行评价,结合相关性分析结果和医院实际情况对标准提出的3种能耗指标的合理性进行阐述.

Residual heat removal system (RHRS) is one of the important and complicated safety systems for Hualong Pressurized Reactor 1000 (HPR1000). Therefore, it is essential to carry out the reliability assessment of the RHRS for HPR1000. In order to fill the gap of how to assess the reliability of the RHRS with uncertainty, the failure mode and effect analysis (FMEA), fault tree (FT) analysis (FTA), and fuzzy Bayesian network (BN) (FBN) methods were applied to establish a novel approach for assessing its reliability. The proposed approach included: (1) identifying the events containing failure modes, failure causes, and resulted failures for the RHRS by FMEA; (2) analyzing the deterministic logical relationship among events, and establishing the FT for the RHRS by FTA; and (3) establishing the FBN model for reliability assessment of the RHRS by FBN according to the transformation process from FT to FBN model, and modifying the conditional probability tables (CPTs) so as to express the event polymorphism and non-deterministic logical relationship between events. The applicability of the approach was validated in East China.

本文采用CFD技术模拟了解剖台内部排风罩排风的气流特性及污染气体的控制效果.研究结果表明:解剖台内部排风罩能够有效控制污染气体向外扩散,降低污染源所散发的污染气体浓度.在解剖台排风罩两侧的呼吸区高度(Z=1.2 m),两边位置排风罩对污染气体的控制效果优于中间位置.在相同的排风量下,90毅排风罩的排污效果要优于35毅排风罩.且污染气体浓度随着排风罩风速的增加而降低.

Astronauts under weightlessness or microgravity would have differences in thermal comfort due to several adaptive physiological changes caused by the absence of the gravity. In this study, the Mahalanobis distance discriminant was conducted to investigate the classifications of the mean thermal comfort votes (MTCV) in weightlessness, in terms of the ratio of low-frequency power (LF) and high-frequency power (HF) of the heart rate variability (HRV). The ratio was abbreviated as LF/HF and it represented the balance of the autonomous nervous system and acted as an indicator of the thermal comfort. This study was based on our previous research data that had been acquired from 6 male participants under simulated weightlessness through heard-down bed rest (HDBR) model. Results showed that when LF/HF < 1.442, participants under simulated weightlessness gave comfort feedbacks, including the neutral comfort and warm comfort, while participants under normal condition felt thermally comfort when LF/HF ≤ 1.232 and felt uncomfortable thereafter. When 1.442 < LF/HF < 2.073, all participants under simulated weightlessness reported cool comfort. When the mean LF/HF was greater than 2.073, however, participants under simulated weightlessness reported thermal discomfort. In addition, results indicated that participants under simulated weightlessness could not distinguish neutral comfort from warm comfort, but they could report the cool comfort quickly, which suggested that the human body in weightlessness might be more sensitive to the cool environments. Finally, the corresponding comfortable air temperature (ta) range under simulated weightlessness was estimated as 26℃ ≤ ta < 30℃ according to the discriminant results of the MTCV.

本文以长沙地区某高校教学楼作为研究对象,建立教学楼的SU模型,并结合长沙地区气候特点和教学楼使用特点,通过EnergyPlus建筑能耗模拟软件,采用改变外墙保温形式、改变外窗传热系数、添加屋面保温层、改变空调设计温度等方式,分析不同节能改造措施对建筑能耗的影响,从而得到适宜的节能方案.

Simulate and compare the air distribution when the air outlets on both sides of the stratified air-conditioning are arranged on the same horizontal plane and the air outlets on both sides are arranged at different levels to study the distribution law of temperature and velocity fields in the workshop. The simulation results show that under the same air supply conditions, when the air outlets on both sides are arranged at different levels, the air velocity in the workshop is lower and the velocity field distribution is more uniform. The temperature distribution effect of the two in the workshop is almost the same.

科学实施二级学院本科教学工作评价,是高校构建有效内部教学质量保障体系的重要任务.南华大学强化以业绩为导向的目标管理,确立二级学院本科教学工作"状态+绩效"评价模式,重构二级学院本科教学工作评价体系,通过评价体系目标制定突出业绩、指标设计紧扣"四个起来"、方法运用坚持多维视角、价值追求指向质量文化四个方面的创新,实现价值取向与技术实现的和谐统一.