Improved Scatter Search Algorithm for Multi-skilled Personnel Scheduling of Ship Block Painting

This paper focuses on the optimization method for multi-skilled painting personnel scheduling.The budget working time analysis is carried out considering the influence of operating area,difficulty of spraying area,multi-skilled workers,and worker’s efficiency,then a mathematical model is established to minimize the completion time. The constraints of task priority,paint preparation,pump management,and neighbor avoidance in the ship block painting production are considered. Based on this model,an improved scatter search(ISS)algorithm is designed,and the hybrid approximate dynamic programming(ADP)algorithm is used to improve search efficiency. In addition,the two solution combination methods of path-relinking and task sequence combination are used to enhance the search breadth and depth. The numerical experimental results show that ISS has a significant advantage in solving efficiency compared with the solver in small scale instances;Compared with the scatter search algorithm and genetic algorithm,ISS can stably improve the solution quality. Verified by the production example,ISS effectively shortens the total completion time of the production,which is suitable for scheduling problems in the actual painting production of the shipyard.

The role of intangible capital in wage inequality between skilled and unskilled workers in China

Wage inequality between skilled and unskilled workers has increased rapidly in China, right along with its major trading partner--the United States. Trade liberalization and technological improvement have been proposed as causes for the inequality, yet trade liberalization and technological improvement have set the stage for another, possibly more important, cause of the inequality： the movement of intangible capital to China. Intangible capital works synergistically with other inputs to make skilled-workers and tangible capital more valuable. Once the accumulated tangible capital reaches a certain level, its lower unit cost will attract the inflow of intangible capital, which will further expand the demand for skilled workers. As a result, wage inequality becomes larger in China. This paper takes the first step in an attempt to understand the role that the movement of intangible capital plays in the increasing wage inequality in China, and sets out several possible policy prescriptions for China to deal with this inequality.

Skill Analysis of Highly Skilled Worker in Optical Fiber Fusion Splicing

In this study, information related to optical fiber fusion splicing skills is consolidated by extracting explicit knowledge of the proficiency levels of skilled technicians in two ways. The first is to visually capture and quantify those skills by identifying differences in the skill levels of a nationally certified technician and a highly skilled expert technician using motion capture software, the other is to explore the relevance of the operation and thinking processes by interviewing the expert technician and then attempt to quantify empirical tacit knowledge by an analysis of mobile tracking views using motion capture software. The results show that a technician＇s ability to engage in ＂sensory thinking＂, such as the proper management of visual and tactile cues, is the most important component of his or her proficiency during optical fiber fusion splicing operations, and it was clear that operations were complemented when work path movements were reduced.

An Evaluation of Training Needs of Supervisors of South African Chemical Weeding Plantation Forest Operations through Forester Perceptions

The success of an annual plan of operations （APO） for a plantation forest management unit （FMU） has great reliance on the capacity of field supervisors who execute it with workers. Foresters＇ perception of skills and performance levels of field supervisors in charge of chemical weeding operations, which are keys to integrated vegetation management strategies at FMUs, were evaluated through a researcher-administered questionnaire implemented through telephone interviews. The research focussed on chemical weeding, of which implementation quality impacts directly on operational costs, worker safety, negative environmental externalities and crop performance. The study was done to establish capacitation requirements （training needs） for the plantation forest sector in the Eastern Cape, Western Cape and KwaZulu-Natal provinces of South Africa. The results of the research identified skills gaps and emotional issues that could be addressed through training. Overall, chemical weeding field supervisors （CWFS） were adequately prepared to perform in most key result areas of planning and leadership. They, however, faced considerable challenges in functions related to controlling and organizing work. In all three provinces, the highest levels of performance inadequacy were in safety and team discipline. Some province-associated peculiarities in field supervisor performances were also identified. Remedial action that foresters recommended was related mostly to the need to strengthen technical and workplace culture management skills. It was observed that effective skills development in CWFS would require planned continuous improvement programmes.

Influence of the Process of Worker on the Mechanical Properties of Carbon Fiber Reinforced Plastic Molded by Autoclave

The present study aims to investigate the difference of the operation process and the significant mechanical properties between expert workers and beginner workers clearly. The influence of the performance of the carbon fiber reinforced plastic (CFRP) molds made by subjects with difference skill level was discussed. Subjects were allowed to choose their process and molding tools. Subject A had 13 years,and subject B had 1 year of professional experience.The time spent usage of tools and process was recorded by a video camera used for analysis and comparison. Mechanical properties assessed in this study include tensile,compressive and Izod impact properties. The working time analysis shows that subject A needs short time for each process. On the other hand,subject B takes twice time to work for each process compared with subject A. From the surface and cross-section observation, it was found that the molding made by subject B had wrinkles all over and the disorderly inter-layer direction; on the contrary,the wrinkles on the molding surface of subject A are barely,and the inter-layer direction of which are more orderly. The results of tensile and Izod impact tests show that the surface winkles have little influence on the mechanical properties of the molding. According to the compression test and failure structure analysis in edge corner part,it was found that it had a great influence on the compression mechanical properties of the sample belonging to different subjects with different experience.