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品牌竞争力影响因素分析

邴红艳

《中国工程科学》 2002年 第4卷 第5期   页码 79-83

摘要：

跨国公司实施全球战略，从产品输出、资本输出到品牌输出，这种以品牌为旗帜，凭借雄厚的资本和先进技术的综合输出，对国内民族品牌形成巨大冲击并提出了严峻挑战。面对外国品牌的大举抢滩，民族品牌竞争乏力的问题日益显露。通过对品牌竞争力影响要素的分析，探讨了提髙品牌竞争力的对策。

关键词： 品牌竞争力     影响因素     分析     对策    

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Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

《农业科学与工程前沿（英文）》 2019年 第6卷 第2期   页码 105-115 doi: 10.15302/J-FASE-2019255

摘要：

The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.

关键词： agro-product     error source     influence factor     near infrared spectroscopy    

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农村绝经后妇女性生活满意度及其影响因素分析

景秀,杨继高,刘俊,张丽华

《中国工程科学》 2014年 第16卷 第5期   页码 105-109

摘要：

为了探索影响农村绝经后妇女性生活满意度的因素，从而为开展老年妇女保健提供科学依据，笔者于2012 年3—8 月采用多阶段随机抽样方法对重庆市5 个区县农村绝经后妇女采用统一方法进行问卷调查和体检。结果显示，重庆市农村绝经后妇女对目前性生活满意和不满意的分别占83.7 %和16.3 %。单因素分析显示，绝经后妇女性生活满意度与其婚姻状况、文化程度、家庭收入、家庭结构、是否患有妇科疾病、最近两周是否有生殖道不适、起居方式、是否需要性生活、性生活频率、老年性保健知识、自觉体力状态及自觉生活状态等12 个变量有关（P<0.05）；多因素Logistic 回归分析显示，分居方式（比值比（OR）=1.711，95 %置信区间（CI）为1.334～2.194）、性生活频率高（OR=1.694，95 % CI 为1.334～2.152）、自觉体力状态差（OR=1.281，95 % CI 为1.018～1.613）是危险因素，家庭收入高（OR=0.651，95 % CI 为0.512～0.826）和既往有妇科疾病（OR=0.689，95 % CI 为0.486～0.977）是保护因素。因此，农村存在多种影响绝经后妇女性生活满意度的相关因素，应重视对绝经后妇女的性教育，改善她们的生活质量。

关键词： 绝经后妇女     性生活满意度     影响因素     Logistic分析    

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硝酸铵膨化理论研究

吕春绪

《中国工程科学》 2001年 第3卷 第9期   页码 58-63

摘要：

描述了硝酸铵膨化过程，计算与测定了其物理化学参数，研究了膨化过程的影响因素，并给出了膨化过程可能的机理。

关键词： 膨化硝酸铵     膨化理论     物理化学参数     影响因素    

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育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

《中国工程科学》 2014年 第16卷 第5期   页码 11-15

摘要：

采取整群抽样调查方法，对2011 年1 月—2013 年5 月在秭归县、夷陵区计划生育服务站因非意愿妊娠而实行人工终止妊娠对象，通过查阅病历资料和调查问卷，了解非意愿性妊娠原因及相关因素。1 360例非意愿妊娠中，未婚为21.62 %，已婚为78.38 %；人群分布在20～39 年龄段（73.82 %）；孕次分布主要在孕2～孕3 的对象为57.87 %；非意愿妊娠中避孕措施失败者为44.34 %，无措施者为55.66 %。避孕措施因素宫内节育器为10.51 %，避孕套为10.51 %，避孕药为8.24 %，外用为6.62 %，其他为8.46 %。存在侥幸心理和取出宫内节育器（IUD）后续措施没能跟进是无措施者导致非意愿妊娠的主要原因。避孕知识知晓率为98.90 %，对紧急避孕的知晓率仅为15.37 %，知道哺乳期需避孕者为18.38 %。医务人员、计生干部、宣传资料是已婚人群获取避孕知识的主要途径，农民及农民工对象获取免费服务高于城镇居民、国家工作人员、商业服务人员及外来流入人员。

关键词： 育龄妇女     非意愿妊娠     人工流产     影响因素    

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Factors influencing peak bone mass gain

Xiaowei Zhu, Houfeng Zheng

《医学前沿（英文）》 2021年 第15卷 第1期   页码 53-69 doi: 10.1007/s11684-020-0748-y

摘要： Bone mass is a key determinant of osteoporosis and fragility fractures. Epidemiologic studies have shown that a 10% increase in peak bone mass (PBM) at the population level reduces the risk of fracture later in life by 50%. Low PBM is possibly due to the bone loss caused by various conditions or processes that occur during adolescence and young adulthood. Race, gender, and family history (genetics) are responsible for the majority of PBM, but other factors, such as physical activity, calcium and vitamin D intake, weight, smoking and alcohol consumption, socioeconomic status, age at menarche, and other secondary causes (diseases and medications), play important roles in PBM gain during childhood and adolescence. Hence, the optimization of lifestyle factors that affect PBM and bone strength is an important strategy to maximize PBM among adolescents and young people, and thus to reduce the low bone mass or osteoporosis risk in later life. This review aims to summarize the available evidence for the common but important factors that influence bone mass gain during growth and development and discuss the advances of developing high PBM.

关键词： peak bone mass     children     adolescents     genetic     risk factors    

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Microbial self-healing of cracks in cement-based materials and its influencing factors

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0986-6

摘要： Cement-based materials are brittle and crack easily under natural conditions. Cracks can reduce service life because the transport of harmful substances can cause corrosion damage to the structures. This review discusses the feasibility of using microbial self-healing agents for crack healing. Tubular and spherical carriers can be used to load microbial self-healing agents and protect microbes, which prolongs the self-healing time. The area self-healing ratio, permeability, mechanical strength, precipitation depth method, numerical modeling, and ultrasonic method can be employed to identify the self-healing effect of cracks. Moreover, the self-healing mechanism is systematically analyzed. The results showed that microbial self-healing agents can repair cracks in cement-based materials in underground projects and dam gates. The difficulties and future development of self-healing cracks were analyzed. A microbial self-healing agent was embedded in the cement-based material, which automatically repaired the developing cracks. With the development of intelligent building materials, self-healing cracks have become the focus of attention.

关键词： cement-based materials     cracks     microbial self-healing agent     mechanism     intelligent building materials    

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Factors influencing the photodegradation of

Bingbing XU, Zhonglin CHEN, Fei QI, Jimin SHEN, Fengchang WU

《环境科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 91-97 doi: 10.1007/S11783-009-0013-8

摘要： In order to provide basic data for practical application,photodegradation experiment of -nitrosodimethylamine (NDMA) in aqueous solution was carried out with a low-pressure Hg lamp. Effects of the initial concentration of NDMA, solution pH, dissolved oxygen, and the presence of humic acid on NDMA photodegradation were investigated. NDMA at various initial concentrations selected in this study was almost completely photodegraded by UV irradiation within 20 min, except that at 1.07 mmol/L, NDMA could be photodegraded almost completely in the acidic and neutral solutions, while the removal efficiency decreased remarkably in the alkaline solution. Dissolved oxygen enhanced the NDMA photodegradation, and the presence of humic acid inhibited the degradation of NDMA. Depending on the initial concentration of NDMA, NDMA photodegradation by UV obeyed the pseudo-first-order kinetics. Dimethylamine, nitrite, and nitrate were detected as the photodegradation products of NDMA. O was found to be the reactive oxygen species present in the NDMA photodegradation process by UV, based on the inhibiting experiments using tert-butanol and sodium azide.

关键词： N-nitrosodimethylamine (NDMA)     ultraviolet irradiation     degradation kinetic     dimethylamine     photodegradation product    

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FACTORS INFLUENCING FOOD-WASTE BEHAVIORS AT UNIVERSITY CANTEENS IN BEIJING, CHINA: AN INVESTIGATION BASED

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 83-94 doi: 10.15302/J-FASE-2022472

摘要：

● Investigate the actual situation of food waste at university canteens in Beijing, China.

关键词： university students     food waste behavior     theory of planned behavior     university canteen    

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Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 184-194 doi: 10.1007/s11783-011-0309-3

摘要： Carbonyl compounds in indoor air are of great concern for their adverse health effects. Between February and May, 2009, concentrations of 13 carbonyl compounds were measured in an academic building in Beijing, China. Total concentration of the detected carbonyls ranged from 20.7 to 189.1 μg·m , and among them acetone and formaldehyde were the most abundant, with mean concentrations of 26.4 and 22.6 μg·m , respectively. Average indoor concentrations of other carbonyls were below 10 μg·m . Principal component analysis identified a combined effect of common indoor carbonyl sources and ventilation on indoor carbonyl levels. Diurnal variations of the carbonyl compounds were investigated in one office room, and carbonyl concentrations tended to be lower in the daytime than at night, due to enhanced ventilation. Average concentrations of carbonyl compounds in the office room were generally higher in early May than in late February, indicating the influence of temperature. Carbonyl source emission rates from both the room and human occupants were estimated during two lectures, based on one-compartment mass balance model. The influence of human occupants on indoor carbonyl concentrations varies with environmental conditions, and may become significant in the case of a large human occupancy.

关键词： carbonyl compounds     indoor air     ventilation     human occupancy     source emission rate (SER)     principal component analysis (PCA)    

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Identifying factors that influence soil heavy metals by using categorical regression analysis: A case study in Beijing, China

Jun Yang, Jingyun Wang, Pengwei Qiao, Yuanming Zheng, Junxing Yang, Tongbin Chen, Mei Lei, Xiaoming Wan, Xiaoyong Zhou

《环境科学与工程前沿（英文）》 2020年 第14卷 第3期 doi: 10.1007/s11783-019-1216-2

摘要： A method was proposed to identify the main influence factors of soil heavy metals. The influence degree of different environmental factors was ranked. Parent material, soil type, land use and industrial activity were main factors. Interactions between some factors obviously affected soil heavy metal distribution. Identifying the factors that influence the heavy metal contents of soil could reveal the sources of soil heavy metal pollution. In this study, a categorical regression was used to identify the factors that influence soil heavy metals. First, environmental factors were associated with soil heavy metal data, and then, the degree of influence of different factors on the soil heavy metal contents in Beijing was analyzed using a categorical regression. The results showed that the soil parent material, soil type, land use type, and industrial activity were the main influencing factors, which suggested that these four factors were important sources of soil heavy metals in Beijing. In addition, population density had a certain influence on the soil Pb and Zn contents. The distribution of soil As, Cd, Pb, and Zn was markedly influenced by interactions, such as traffic activity and land use type, industrial activity and population density. The spatial distribution of soil heavy metal hotspots corresponded well with the influencing factors, such as industrial activity, population density, and soil parent material. In this study, the main factors affecting soil heavy metals were identified, and the degree of their influence was ranked. A categorical regression represents a suitable method for identifying the factors that influence soil heavy metal contents and could be used to study the genetic process of regional soil heavy metal pollution.

关键词： Soil     Heavy metal     Influencing factor     Categorical regression     Identification method    

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Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

Hongwei Yu,Junrong Shao,Huawei Jia,Diga Gang,Baiwen Ma,Chengzhi Hu,

《工程（英文）》 doi: 10.1016/j.eng.2023.02.007

摘要： Microplastics (MPs; < 5 mm) have become one of the most prominent global environmental pollution problems. MPs can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall, potentially threatening the structure and function of natural ecosystems. MPs in terrestrial and aquatic ecosystems alter the growth and functional characteristics of organisms. However, little attention has been given to the possible harm associated with MPs deposited in snow, particularly in the context of global climate warming. MPs collected from surface snow in the Inner Mongolia Plateau, China, were used for quantitative analysis and identification. The results showed that MPs were easily detected, and the related concentration was approximately 68 ± 10–199 ± 22 MPs·L−1 in snow samples. Fibers were the most common morphology, the polymer composition was largely varied, and the abundance and composition of MPs were linked to human activity to a great extent. High-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics, indicating a considerable difference in microbial functional diversity. MPs may have an interference effect on the individual growth and functional expression of microorganisms in snow. In addition, the results showed that functional living areas (e.g., landfills and suburban areas) in cities play an important role in the properties of MPs. For instance, the highest abundance of MPs was found in thermal power plants, whereas the abundance of polymers per sample was significantly lower in landfills. The MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health.

关键词： Human activities     Snow     Microplastics     Microbial community     Urban function     Environmental effect    

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Antibiotic resistance genes in manure-amended paddy soils across eastern China: Occurrence and influencing

《环境科学与工程前沿（英文）》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1499-y

摘要：

• Manure fertilization resulted in antibiotic residues and increased metal contents.

关键词： Pig manure     Antibiotics     Metals     Antibiotic resistance genes     Paddy fields    

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Analysis of synergy degree and its influencing factors in hydropower EPC project management

Jiwei ZHU, Hua GAO, Jiangrui WANG

《工程管理前沿（英文）》 2021年 第8卷 第3期   页码 402-411 doi: 10.1007/s42524-020-0098-0

摘要： The use of engineering procurement construction (EPC) mode is currently a trend in hydropower engineering construction. The clarification of the internal relationship between hydropower EPC projects and the realization of synergy has great significance in improving management efficiency and implementation effect. In this work, a three-dimensional system and a system model of hydropower EPC project management synergy are constructed. The mechanism and factors that influence the degree of management synergy are analyzed on the basis of management synergy theory. Furthermore, the evaluation index system and the degree of synergy model are established, and grey relational analysis is utilized to identify the key factors that affect the synergy degree. Thus, this study aims to facilitate the hydropower EPC project management synergy, provide a quantitative method for synergy degree evaluation, and propose corresponding promotion strategies. Results show that the order degree of each subsystem presents a steady upward trend. Specifically, the order degree of the subsystem at the trial operation stage is low, which is the major restriction on the further improvement of the synergy degree of EPC project management. The key factors in improving the synergy level of hydropower EPC project management are mainly concentrated in the information and organization synergy subsystems, including the construction degree of information platform, the performance of functions, the timeliness of information transfer, and the functions of the information platform.

关键词： hydropower project     EPC mode     synergy degree model     grey relational analysis    

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Factors influencing water quality indices in a typical urban river originated with reclaimed water

Jiao Zhang, Zhen Wei, Haifeng Jia, Xia Huang

《环境科学与工程前沿（英文）》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0943-5

摘要： The water quality in a typical urban river segment originated with reclaimed water in Beijing was monitored for two years to investigate the evolution of water quality along the river, and statistical analysis was applied to determine factors influencing water quality of such river recharged by reclaimed water. It was found that no significant change in pollutant concentrations (including COD, NH -N, TN and TP) was observed during this time, and their average values were close to those of the original reclaimed water. However, turbidity and algal contents fluctuated temporally in the direction of river flow. Statistical analysis showed that turbidity was strongly positively correlated with algal contents for flow rate<0.1 m·s , whereas it was strongly positively correlated with both algal contents and TOC for flow rate>0.1 m·s . It was observed that diatom was the absolute predominant phyla with as the major species. In terms of algal bloom control, the specific growth rate of algae was strongly correlated to temperature, and was influenced by flow rate as well. Compared with two other rivers originated with reclaimed water and one originated with natural water, the Shannon–Wiener index in the objective river was the lowest, with values between 0.7 and 1.6, indicating a high risk for algal bloom. Statistics showed that Shannon–Wiener index was strongly negatively correlated to nutrient salts and cations.

关键词： Reclaimed water     Urban river     Turbidity     Algae     Flow rate    

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标题 作者 时间 类型 操作

品牌竞争力影响因素分析

邴红艳

期刊论文

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

期刊论文

农村绝经后妇女性生活满意度及其影响因素分析

景秀,杨继高,刘俊,张丽华

期刊论文

硝酸铵膨化理论研究

吕春绪

期刊论文

育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

期刊论文

Factors influencing peak bone mass gain

Xiaowei Zhu, Houfeng Zheng

期刊论文

Microbial self-healing of cracks in cement-based materials and its influencing factors

期刊论文

Factors influencing the photodegradation of

Bingbing XU, Zhonglin CHEN, Fei QI, Jimin SHEN, Fengchang WU

期刊论文

FACTORS INFLUENCING FOOD-WASTE BEHAVIORS AT UNIVERSITY CANTEENS IN BEIJING, CHINA: AN INVESTIGATION BASED

期刊论文

Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

期刊论文

Identifying factors that influence soil heavy metals by using categorical regression analysis: A case study in Beijing, China

Jun Yang, Jingyun Wang, Pengwei Qiao, Yuanming Zheng, Junxing Yang, Tongbin Chen, Mei Lei, Xiaoming Wan, Xiaoyong Zhou

期刊论文

Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

Hongwei Yu,Junrong Shao,Huawei Jia,Diga Gang,Baiwen Ma,Chengzhi Hu,

期刊论文

Antibiotic resistance genes in manure-amended paddy soils across eastern China: Occurrence and influencing

期刊论文

Analysis of synergy degree and its influencing factors in hydropower EPC project management

Jiwei ZHU, Hua GAO, Jiangrui WANG

期刊论文

Factors influencing water quality indices in a typical urban river originated with reclaimed water

Jiao Zhang, Zhen Wei, Haifeng Jia, Xia Huang

期刊论文