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关键词： 铬污染   水力梯度   浓度梯度   治理  

摘要： 通过调查研究污染物在地下水系统中迁移转化产生的现象,对污染物在自然状态下迁移转化的水动力方式,即水力梯度或浓度梯度作出判断。在此基础上,选择适宜部位人为地为地下水中铬污染物提供水动力条件,迫使污染物有组织地从地下水系统中迁移出来,并进行处理或就地转化。根据重点污染部位的污染现象,研究形成了6种污染治理方法。其中5种方法进行了现场实施和验证。

关键词： 深度学习   空中目标意图识别   信息分类处理   噪声标签   多尺度嵌入图学习  

摘要： 针对传统深度学习意图识别方法难以在噪声标签存在时获得可靠模型的问题，该文提出基于信息分类处理(ICP)网络和多尺度鲁棒学习的空中目标意图识别(ATIR)方法。首先，基于空中目标属性性质，构建基于ICP的编码器，以获得更具可分性的嵌入;随后，设计了从精细到粗糙的跨尺度嵌入融合机制，利用不同尺度的目标序列，训练多个编码器来学习判别模式;同时，利用不同尺度的互补信息，以交叉教学的方式训练每个编码器，以选择小损失样本作为干净标签;对于未选定的大损失样本，基于多尺度嵌入图和说话者-倾听者标签传播算法(SLPA)，使用干净样本的标签进行校正。在不同标签噪声类型、多级噪声水平的ATIR数据集上的实验结果表明，该方法的测试准确率和Macro F1分数显著优于其他基线方法，说明其具有更强的噪声标签鲁棒性。

关键词： 无甲醛   环保   消音风管  

摘要： 文章对采用新型材料无甲醛环保消音风管的原理、特点、制作、安装、注意事项等方面进行论述,以用于指导无甲醛环保消音风管的施工.

关键词： 卫星遥感   无人机航空摄影   合成孔径雷达   矿山生态环境监测   生态修复  

摘要： 矿产资源的开发会对周边生态环境产生负面作用，影响当地居民的生产生活。相比传统的矿山生态环境地面监测手段，遥感技术具有宏观性、动态性和经济性等优势，其高波谱分辨率、高空间分辨率及高时间分辨率，能全方位动态反映矿山生态问题现状与发展趋势。陕北煤炭基地是中国重要的煤炭能源基地之一，本研究选择其中一座生产矿山作为研究区，综合运用光学遥感和雷达遥感技术，精准捕捉煤矿开采活动所诱发的地面塌陷、土地损毁以及地表水体、植被状况等区域要素特征;针对重点监测区，进一步引入无人机遥感技术，实现对地裂缝、不稳定边坡等局部要素的精细化监测与识别，系统构建了数据获取、数据处理、遥感解译、数据分析等全流程矿山生态环境遥感监测技术体系。研究结果表明，多源遥感技术凭借卓越的全局视野、宏观分析能力及强大的数据追溯性，在矿山生态环境监测领域展现出了无可替代的优势，应用成效显著。在此基础上，提出了未来矿山生态环境监测预警智能体系“多网融合+实时监测+智能作业+任务协同+全面感知+自主决策”的发展方向。

关键词： Influencing factors   Noise, occupational   Personal attenuation rating   Personal protective equipment  

摘要： To analyze the correct use of personal protective equipment (PPE) among noise-exposed workers and its influencing factors, providing reference information for noise intervention efforts. In September 2023, a stratified sampling method was employed. Based on the 2022 gross domestic product (GDP) rankings of cities in Guangdong Province, 21 prefecture-level cities were divided into economically developed and less developed groups. Two cities were randomly selected from each group, and 16 to 17 enterprises were randomly chosen from each city as study sites. Twenty workers were included from each enterprise as study subjects. A total of 1200 questionnaires were distributed and collected, and 1099 were valid, with an effective recovery rate of 91.6%. The correctness of hearing protector usage was evaluated according to the GB/T 23466-2009 "Guidelines for the Selection of Hearing Protectors", and the personal attenuation rating values of the workers' hearing protectors were measured. A self-designed Questionnaire on the Use of Hearing Protectors by Noise-Exposed Workers was used to investigate PPE-related usage. Multivariate logistic regression analysis was conducted to identify factors influencing the correct use of PPE. A total of 429 (39.0%) noise-exposed workers were able to use PPE correctly during work. Multivariate logistic regression analysis showed that age, working hours, gender, occupational noise protection knowledge score, whether PPE was checked after use, and the frequency of peer supervision on PPE usage were significant factors influencing the effective use of PPE (<0.05) . The correct use of PPE by noise-exposed workers still needs to be improved. The level of occupational health education in enterprises should be enhanced to promote the correct use of PPE by noise-exposed workers.

关键词： Body mass index   Hypertension   Interaction   Noise, occupational   Systemic inflammation  

摘要： To investigate the interaction of workplace noise, body mass index (BMI) and systemic inflammatory response on hypertension. In January 2019, 1124 male workers from an automobile factory in Wuhan were selected by cluster random sampling method. The study population was divided into normal body weight group (BMI<24 kg/m(2)) and overweight group (BMI≥24 kg/m(2)) according to BMI, and were followed up for 3 years. The occupational health examination of the workers was carried out every year, blood routine and blood biochemical indexes were collected, and the information of the workers' age, BMI, type of work and age of exposure to injury were collected through field questionnaires. The noise intensity of the workplace of the enterprise was measured for 3 consecutive years, and the equivalent sound level was calculated according to the working time. Normal and skewness measurements were described by Mean±SD and [ ((1), (3)) ], respectively. test or Wilcoxon rank sum test was used for inter-group comparisons. Categorical variables were expressed by frequency and percentage (%), and Chi-square test was used for inter-group comparisons. Mixed effects models and generalized estimation equations were fitted to analyze the relationship between occupational noise, systemic inflammation, and their interaction terms with blood pressure and hypertension risk. Univariate analysis revealed that the white blood cell counts, neutrophil counts, lymphocyte counts and eosinophil counts were positively associated with systolic blood pressure and diastolic blood pressure in overweight group (=467), respectively (<0.05). The participants with white blood cell counts≥5.94×10(9)/L, neutrophil counts≥3.31×10(9)/L, lymphocyte counts ≥2.03×10(9)/L, and eosinophil counts ≥0.12×10(9)/L had increased risk of hypertension by 52% (=1.52, 95%: 1.11-2.05), 37% (=1.37, 95%: 1.01-1.83), 58% (=1.58, 95%: 1.18-2.09), and 52% (=1.52, 95%: 1.12-2.06), respectively (all <0.05). Multivariate analysis found

关键词： Estimation model   Fixed point noise intensity   Individual noise exposure dose   Manufacturing   Noise, occupational   Occupational exposure   Spatial distribution of noise   Workplace  

摘要： To develop an individual noise exposure dose estimation model based on spatial distribution of noise in order to provide reference for occupational health management and hearing loss risk assessment caused by noise in workplace. From July 2018 to October 2019, 10 noise-exposed positions and 48 employees in 3 high-noise workplaces of a manufacturing enterprise in Sichuan Province were selected as the research objects. Occupational health survey, fixed-point measurement of workplace noise and individual noise measurement were used to obtain noise intensity and employee exposure information. The mean noise intensity and the corresponding exposure time were weighted to estimate the individual noise exposure dose estimation model based on the spatial distribution of workplace noise, and the paired test was used to evaluate the accuracy of the individual noise exposure dose estimate (8 h equivalent sound level, L(EX, 8h)) based on the spatial distribution of workplace noise and the measured value of individual noise exposure dose. And the least square regression model was used to correct it. The daily noise exposure dose of 44 (91.7%) of 48 workers in 10 types of work in 3 sites of the manufacturing enterprise exceeded the standard, and the maximum noise exposure intensity was up to 108.3 dB (A). The measured value of individual noise exposure dose was higher than L(EX, 8h), and the difference was statistically significant (<0.001). The noise difference distribution was mostly positive and symmetrical (=0.958). The measured noise exposure dose of 6 out of 10 work types in 3 sites was higher than L(EX, 8h) (all <0.05), and there was a linear correlation between the measured dose and L(EX, 8h) (=0.373, <0.05). Considering the influence of systematic error and the construction, diagnosis and screening of adaptive assessment model, an individual noise exposure dose estimation model based on the spatial distribution of workplace noise was finally obtained: =0.574+45.250, whe