Antecedents of early career stage mentoring among Chinese employees

This study examined the mediating influence of protege‐initiated mentoring relationships on the relationship between personality and situational characteristics and mentoring received. Data were obtained from Hong Kong Chinese graduate employees (N=184) in their early career stage. Results of the regression analysis showed that protege‐initiated mentoring relationships mediated the relationship between the personality (extraversion) but not the situational (individual development culture and opportunities for interactions on the job) characteristics and mentoring received. In other words, extraversion was indirectly related to mentoring received through protege‐initiated mentoring relationships but individual development culture and opportunities for interactions on the job were directly related to mentoring received. Additionally, opportunities for interactions on the job indirectly influenced mentoring received through protege‐initiated mentoring relationships. Limitations of the study, implications of the findings and directions for future research are discussed. Copyright © 1999 John Wiley & Sons, Ltd.     

建筑火灾增长阶段室内温度的时间特性研究

为研究建筑火灾增长阶段室内温度的时间变化规律,提出了高温烟气的主要几种热损失的计算方法,发展了受火室与未受火室及环境的热平衡方程,并采用牛顿-拉菲尔森法迭代得到受火室的温度变化.计算了慢速、中速、快速、超快速四种火灾增长速率下,受火室气相温度及烟气热损失随时间的变化.本文的研究方法及有关结果可以为建筑防火及安全疏散提供有力依据.     

Inherent occupational health assessment during basic engineering stage

Each year more people die from work-related diseases than are killed in industrial accidents. Therefore it is essential to evaluate occupational health aspect during the process design. Early evaluation of safety, health, and environmental (SHE) performance is advantageous, since the opportunities to make the process inherently benign are greater and the cost therefore lower. The methods for occupational health assessments need to be tailored to specific design stages, since the data availability is changing as the design proceeds. In this paper, an index-based method called the Occupational Health Index (OHI) is presented for the basic engineering stage. The OHI is the final of the three methods in series proposed for health assessment in development and design stages. The OHI is based on the information available in piping and instrumentation diagrams (PIDs) and the plot plan. Four health aspects are considered; chronic inhalation risks to noncarcinogens and carcinogens, acute inhalation risk, and dermal/eye risk. The index is demonstrated on separation system of a toluene hydrodealkylation process. The assessment results allow the level of occupational health risks to be evaluated, the sources of exposures be detected, and corrective actions taken in a focused way.     

Inherent occupational health assessment during preliminary design stage

Chemical process routes can already be assessed as early as in the development and design phases. Process screening should not look at economic and technical aspects only, but also the safety, health, and environmental performances. In this paper, a method called the Health Quotient Index (HQI) is presented for the preliminary process design phase. The HQI provides a simple approach to quantify workers' health risk from exposure to fugitive emissions e.g. in petrochemical plants. The method utilizes process data from flow sheet diagram, which is already available at the preliminary design stage. Since the mechanical details of the process are still unknown, a database of the precalculated fugitive emissions for typical operations in chemical plants was created to simplify the assessment. The HQI can be used to rank alternative process concepts or to quantify the risk level of processes. As a case study, six process routes for producing methyl methacrylate are discussed. Three health indexes are compared in the case study. The HQI is able to highlight the difference of hazard levels between the routes better as a result of more detailed assessment of the exposures.     

Study on the early stage of runaway reaction using Dewar vessels

In this paper, compared with a UN cylindrical 500 mL Dewar (H.4 in the UN tests), a spherical 1 L Dewar vessel was used to study the early stages of runaway reactions of several liquid and solid samples, including three organic peroxides and a reactive material. The samples were filled in the vessels and the temperature profiles versus times at different positions of the samples were measured. As a result, the minimum temperatures, defined as the SADT, were averagely 10 K lower than those measured in the cylindrical Dewar vessels. At the same time, the temperature profiles of solids in the spherical Dewars tended to be homogeneous. The heat transfer coefficient of a spherical Dewar is only 0.18 W/K/m, one-eighth of a conventional cylindrical Dewar vessel. Meanwhile it has a low phi factor. These factors are essential to simulate low heat loss bulk conditions in the equilibrium process and at the early stage of a runaway reaction. To characterize the ability of the adiabaticity of a storage vessel, it can be seen that a spherical Dewar could simulate the plant process having critical storage size of a reactive-material, r₀, approximately 0.6 m. It is recommended that such a technique is used to investigate the SADT of an unstable material in larger scale packaging or a material with very weak heat release in industry.     

Computer-aided assessment of occupationally healthier processes during research and development stage

Each year more people die from occupational related diseases than are killed in industrial accidents. Therefore it is critical to start considering health aspect early when developing a new chemical process. In this paper, a computer-aided tool for assessing inherent occupational health is proposed for chemical process research and development stage. The method was developed based on the reaction chemistry data, which is the only data available at this stage. Three types of approaches were formulated to calculate the route index value using additive type, average type and worst case type calculations. The tool can be used to rank the alternative chemical synthesis routes by their health properties as well as characterize the hazard level of single process. Finally the tool was applied to six process routes for methyl methacrylate production for demonstration. The case study revealed hazards of the processes from different perspectives, e.g. the results from the additive-type calculation were mainly affected by the total number of steps in the route, which indicates the impact of process complexity on the level of hazard. The introduction of such tool provides a swift yet reliable means that will encourage health criteria to be considered earlier in process development besides economic, safety and environment.     

生态土壤渗滤系统启动周期研究

利用室内模拟试验装置,考察了4种生态土壤渗滤系统在0.1 m3/(m2·d)的水力负荷条件下对生活污水中TP、COD和NH3-N的去除效果及启动周期; 同时对整个系统及同类生态工艺启动周期的判断方法做了探讨.研究结果表明,生态土壤渗滤系统对TP、COD和NH3-N的启动周期分别为15～27 d、24～40 d和24～26 d; 土壤渗滤系统对TP的启动周期最短,对COD的启动周期最长; 处理系统启动周期的判断原则是综合考察系统对主要污染物各自的启动周期,以最长的作为系统启动周期.4组试验中,1#和2#系统的启动周期为40 d; 3#和4#的为24 d.     

The effect of career stage on the meaning of key organizational events

This study addresses the question of how career stage affects the meaning managers attribute to key organizational events. Propositions were developed suggesting that career stage provides a frame of reference when interpreting events and that the frequency with which this frame of reference is used differs in each career stage. In depth interviews with 40 managers across three career stages supported these propositions.     

水电工程施工阶段应急管理系统脆弱性评价

为有效评估水电工程施工阶段应急管理系统应急能力并发现系统中的薄弱环节,提出一种应急管理系统脆弱性评价方法。首先,引入脆弱性理论,将应急管理系统的脆弱性分为暴露性、适应性和恢复性3部分;然后,根据水电工程施工阶段应急管理系统的特点构建了进攻性和防御性指标体系,并运用ANP（网络层次分析法）计算各指标权重,结合灰色聚类分析得到各防御性指标和系统整体的脆弱性系数,从而判断水电工程施工阶段应急管理系统脆弱性等级;最后,运用该模型对国内某水电站工程应急管理系统进行评价,在定量计算的基础上得到该应急系统的脆弱性等级,结果表明该系统脆弱性等级处于中等状态,并发现其薄弱环节,为完善水电工程施工阶段应急管理系统的建设提供支撑。     

Inherent occupational health assessment during process research and development stage

Occupational health studies the interaction of work and health, especially the long-term effect of chemicals to health. In this paper an Inherent Occupational Health Index has been developed for assessing the health risks of process routes during process research and development stage. The method takes into account both the hazard from the chemicals present and the potential for the exposure of workers to the chemicals. The index can be used either for determining the level of inherent occupational health hazards or comparing alternative process routes for these risks. The method is tailored for the process research and development stage by including only such properties of chemicals and operating conditions of process, which are available already in this early stage. In the end of this paper the approach is demonstrated by comparing the inherent occupational healthiness of six methyl methacrylate process routes using three different types of index calculations; additive-type, average-type, and worst case-type. The study discloses that the average- and worst case-based approaches analyze the characteristics of a route better than the additive calculation, which is greatly affected by the number of steps in the route. A quantitative standard scale for the index is also developed to allow health level assessment of a single process.     

Organizational commitment,career factors and career/life stage

A model of organizational commitment was developed using, as independent variables, factors associated with self, with family and with career. Australian military officers (males only) were used as the research population (N=13OO). All these factors were influential in explaining the variance in organizational commitment. Examination of the interplay of the independent variables across career/life stages gives insight into the dynamics of organizational commitment.     

基于灰色聚类方法的航空公司飞机进近着陆阶段安全性评估

进近着陆阶段时间短、任务重、环境复杂,是飞行事故多发阶段。飞行机组应当具备过硬的心理素质和熟练的驾驶技术,严格执行标准操作程序,提升稳定进近能力和复飞的决断能力,保障飞行安全。本文通过综合分析民用飞机在进近着陆时的影响因素和QAR译码数据,建立相关指标体系,构造出相应灰色聚类评价模型,根据综合聚类系数对航空公司某阶段飞机进近着陆安全性进行评估。该研究为航空公司进行进近着陆阶段安全性评估提供了一种较为科学的定量化依据,对于保障飞行安全具有现实意义。     

现阶段我国地震应急技术框架分析及评价

破坏性地震发生后,快速高效地开展地震应急工作离不开地震应急技术的基础支撑。为进一步掌握我国地震应急技术现状,持续增强我国应急能力,通过梳理现阶段我国地震应急指挥、地震烈度调查与损失评估、地震现场流动监测3大技术系统,从技术构成、技术功能、存在问题等方面探讨我国现有地震应急技术。结果表明:现阶段我国的地震应急技术发展显著,但仍存在不足和薄弱环节,标准化、智能化、综合化或将成为新方向。     

Burning velocity evaluation from pressure evolution during the early stage of closed-vessel explosions

In the present paper, a comprehensive set of data on explosions in a spherical and a cylindrical vessel with central ignition was examined in order to check the validity of the cubic law, empirically found by many authors for explosions in small- and medium-size closed vessels. Experiments were performed on propylene–oxygen mixtures, in the presence of various additives (Ar, N₂, CO₂, CH₂BrCl or exhaust gases), at total initial pressures p₀ from 0.3 to 1.3 bar. For this pressure range, the cubic law was found valid for pressure rise Δp≤p₀ and the cubic law constants were evaluated by a non-linear regression analysis. These constants were further used to compute the burning velocities of the examined systems according to the isothermal and adiabatic compression models. This simple and reliable method for burning velocity determination may find an useful application to complex systems, formed either by a composite fuel (landfill gas, gasoline, Diesel fuel) and air or by single fuel–air mixed with composite additives (i.e. their own exhaust gases).     

The influence of career stage on the work attitudes of male and female accounting professionals

The present study compared work commitments, overall job satisfaction, intrinsic and extrinsic rewards satisfactions, and organizational and professional turnover intentions of 718 male and female accounting professionals at different career stages. Career stage was measured by professional tenure. The results indicate that there are some differences in work attitudes across career stages for male accounting professionals. Job involvement, organizational commitment, and intrinsic and extrinsic rewards satisfaction are positively related to professional tenure. Organizational turnover intentions are negatively related to professional tenure for male accounting professionals. There are no significant differences in work attitudes across career stages for female accounting professionals. An examination of reasons for differences in work attitude patterns between male and female accountants suggests the need for research to determine whether later career stages (advancement and maintenance) differ for men and women. The results also suggest that future research should consider defining career stage in terms of the overlap between stages defined using alternate career stage measures.     

资质评定再扬帆中安协安防工程企业资质评定第二批扩大试点正式启动

2006年,经公安部科技局批准,中国安全防范产品行业协会(以下简称中安协)在北京、天津、湖北三省市开展了工程企业资质评定的第一批试点.从已经取得的结果看,成绩可谓不菲,三省市共有500多家工程企业提出了申请,颁发企业资质证书约400家.……     

基于YOLO-BP神经网络的古建筑修缮阶段火灾监测方法*

为提高古建筑修缮阶段火灾监测水平,有效预防火灾事故,提出1种基于YOLO-BP神经网络算法的古建筑修缮阶段火灾监测模型。针对修缮作业对古建筑产生的消防隐患,在施工场地设置监测点,并利用YOLO算法以火源、可燃物为目标进行检测与定位,计算火源与可燃物距离;以火源温度、含氧量、火源与可燃物距离3项指标作为BP神经网络输入层,以火灾概率为输出层,从而进行预测;基于古建筑修缮阶段焊接、切割动火作业阶段的样本数据进行仿真模拟。结果表明:利用模型监测古建筑修缮阶段火灾的准确率达93.9%,验证模型的可靠性;当火源温度在150~2 000 ℃范围内,含氧量不小于19.5%时,动火作业安全距离为10.1 m。     

地铁施工阶段险兆事件自愿上报意愿影响因素研究

为提高地铁施工阶段险兆事件自愿上报水平,研究地铁施工阶段险兆事件自愿上报意愿的影响因素,通过文献查阅和访谈等方法归纳出险兆事件自愿上报意愿的影响因素,建立险兆事件自愿上报意愿指标体系。基于组合赋权法计算的权重对各指标进行重要性排序,并提出提高险兆事件自愿上报水平的对策建议。结果表明:认知水平、未对上报者和当事人保密、存在责备及苛责文化和无惩罚制度没有充分落实是地铁施工阶段险兆事件自愿上报意愿的关键影响因素。     

Inherently safer design of solvent processes at the conceptual stage: Practical application for substitution

The implementation of inherently safer design concepts is considered beneficial to avoid hazards during early stages of design. The application of existing process design and modeling techniques that aid ‘substitution’, ‘intensification’ and ‘attenuation’ has been shown in this work. The techniques have been applied to solvent processes because of the inherent hazards associated with them, such as large inventories, and presence of highly toxic and flammable materials. For ‘substitution’, computer aided molecular design technique has been applied to select inherently safer solvents for a solvent operation. For ‘intensification’ and ‘attenuation’, consequence models and regulatory guidance from EPA RMP have been integrated into process simulation. Combining existing techniques provides a design team with a higher level of information to make decisions based on process safety. A case study has been shown for liquid extraction of acetic acid–water mixture. Suitable solvents were identified using ICAS 11.0-ProCAMD, and consequence models were integrated into Aspen plus simulator using a calculator sheet. Solvents such as 5-nonanone, 2-nonanone and 5-methyl-2-hexanone provide inherently safer options, but conventionally-used solvent, ethyl acetate, provides higher degree of separation capability. A conclusive decision regarding feasible solvents and operating conditions would depend on design requirements, regulatory guidance, and safety criteria specified for the process. Inherent safety has always been an important consideration to be implemented during early design steps, and this paper presents a methodology to incorporate the principles and to obtain inherently safer alternatives.     

二次采动下沿空留巷围岩变形及其控制研究

针对二次采动下沿空留巷围岩变形控制困难问题,揭示了沿空留巷围岩变形规律,建立了二次采动下沿空留巷围岩变形力学模型,推导出了围岩变形的理论公式,据此分析了围岩变形的影响因素,提出了支护对策,并进行了工程实践。结果表明:围岩变形理论公式与现场实测值基本一致;顶底板移近量以底鼓为主,底鼓量为直接底压曲量与老底挠曲量的最大值;各因素对围岩变形影响程度依次为巷旁支护体宽度、迭加应力集中系数、采高、采深、老底弹性模量。围岩变形控制对策应围绕关键性影响因素进行,据此提出“锚网索+高强度墩柱+老底注浆”耦合支护对策,工程实践表明,沿空留巷围岩变形稳定,得到了有效控制。