Design of variable stiffness fixture for computerized embroidery machine based on shape memory polymer

It is a challenge to handle the metal fixture used for cloth clamping in a computerized embroidery machine because of its fixed stiffness. Herein, a prototype that acts as a fixture to provide variable stiffness property is explored by discussing the potential of a thermal-sensitive epoxy resin-based shape memory polymer (SMP). The general model of fixture design is obtained after analyzing the working condition of the metal fixture. The structure of the SMP fixture is designed by discussing the material properties and working requirements of SMP, and a theoretical model is established to deduce the relationship between thickness and stiffness of the fixture. Six SMP fixtures that memorized clamping and opening state were manufactured with different proportions of raw materials. The results show that the designed fixtures have a lighter weight but higher clamping force than the metal fixture at room temperature (RT). It is the first work that demonstrates the potential of the SMP fixture to replace the metal fixture in the computerized embroidery machine and provides inspiration for product design with variable stiffness characteristic in engineering.

High-performance work practices lecturers’ performance connection: Does working condition matter?

Poor performance of lecturers in Nigerian Polytechnics warrants independent research on lecturers’ job performance, given that the poor performance has seriously affected educational development in the country. Substantial evidence from the extant literature has highlighted that high-performance work practices are significant predictors and drivers of enhanced performance. Also, the functionality of high-performance work practices is context-dependent. Therefore, the current study investigates the effect of high-performance work practices (recruitment and selection, training and development, and employee involvement) on lecturers’ performance in the context of Nigerian polytechnics. It also examines the moderating role of working conditions in the high-performance work practices’ relationship with lecturers’ performance. Data were obtained from 539 academics in the North-west Nigerian polytechnics. The overall findings indicate that training and development and employee involvement are significant predictors of enhanced lecturers’ performance, and working condition strengthens the recruitment and selection–performance connection and employee involvement–performance relationship. This implies that the link between HR practices and enhanced performance could be affected by the environment within which organizations operate. The present study focused mainly on teaching staff from the polytechnics located in the north-central geopolitical zone of Nigeria. Thus, other geopolitical zones and non-teaching staff from various polytechnics could be studied further by future studies.

A study on diesel engine crankshaft bearing failure analysis with consideration of bearing lubrication

Purpose The edge of diesel engine crankshaft main bearing is more likely to fail in its real working condition. This paper aims to study the bearing failure mechanism by finding the relationship between bearing lubrication characteristics and its working condition. Design/methodology/approach This work builds the mixed lubrication model of crankshaft bearing to analyze the cause of bearing abnormal wear, and the finite difference method was used to solving the average Reynolds equation. During the analysis, journal misaligned angle, external load and roughness are considered. Findings The result shows that the wear of the diesel engine crankshaft bearing happens in engine startup phase and the bottom of the bearing are more prone to be excessively worn. Under the influence of journal misalignment, bearing asperity contact load and speed range of mixed lubrication will increase markedly. The edge of the bearing will be excessively worn. The effect of misalignment on bearing lubrication performance varies under different shaft rotation speed. Originality/value The former research studies on crankshaft bearing either just focused on its lubrication characteristics or interested in its failure types (wear, adhere, cavitation). This paper studies the relationship between bearing failure mechanism and lubrication performance.

Explaining Challenges Experienced and Evaluation of the Working Condition of Midwives: A Mixed-method Study Protocol

BackgroundMidwifery is one of the most important jobs in maintaining community health. Various factors can reduce job productivity and cause physical and psychological complications in midwives. The present study aims to: a) explain challenges experienced by midwives; b) evaluate the working condition in midwifery working settings. MethodsThis mixed-methods study consists of three phases. The first phase is a qualitative study explaining challenges experienced by midwives. In this phase, the subjects will be selected through purposive sampling; moreover, in-depth individual interviewing will be used for data collection. Then, the conventional content analysis approach will be employed for data analysis. The second phase will be used a cross-sectional approach for evaluating the working condition in midwifery working settings. In this regard, a multistage cluster sampling method will be used to select 293 subjects who work in the hospital and health care centers. Finally, using findings of the qualitative and quantitative phases and nominal group technique some strategies will be given to reduce challenges of the midwifery working settings.DiscussionThe present research is the first study to investigate the challenges experienced and working conditions among midwives in working settings. For the purposes of the study, a mixed-methods approach will be used which aims to develop strategies for creating suitable working conditions. It is hoped that the strategy proposed in the current study could lead to improvements in midwife’s satisfaction and health care services.Ethical codeIR.TBZMED.REC.1400.113.

TRADE UNIONS AND BASIC INCOME: SOME DANISH EXPERIENCES

Theoretically, there are many good arguments that unions should support a proposal on basic income. The main reason for the Danish trade unions resistance to basic income reform is that it would go against the short-term interest of the unions in organisational self-maintenance. Trade unions will lose power in relation to their members with a basic income. Trade unions have control over individual members by virtue of the collective agreement system and the labour law system. If you have a basic income system, the individual worker will decide when he or she wants to leave his workplace and strike. Suppose a single worker or a group of workers leave their workplace because of dissatisfaction with the working condition. In that case, they will be punished financially according to the rules of labour law rely on any support from their trade union.

Problems and Challenges of Foreign Labour Migrants

This paper is based on problems and challenges of foreign labour migration and the main aim of this paper is to identity the problems and challenges faced by migrant workers in the destination countries, and is based on five different manpower agencies. Information was collected through 255 respondents and respondent’s household’s information and descriptive and cross sectional research design and sample selection has been based on purposive method. About 37.3 percent foreign labour migrants want to go Malaysia and highest i.e. 29.4 percent respondents want to go foreign labour work by cause of poverty and 23.5 percent respondents by cause of unemployment. More than 90 percent respondents do not have any knowledge about right of foreign labour migrants. Total 163 respondents had returned from foreign labour migration; the highest 36.2 percent respondents are returned back from Malaysia. More than 55 percent foreign labour migrants stayed in foreign employment for 2-4 year and 35 percent returned migrants engaged in factory labour and 36 percent foreign labour returned migrants worked 12 hours. The highest i.e. 60.8 percent returned foreign labour migrants were sick of frequent fever and 58.8 percent foreign labour returned migrants had their treatment charge paid by their companies. Lack of information about the adequate the destination countries, poverty, unemployment, manpower agencies or agents’ exploitation, discrepancy in wages before and after departure, working condition and situation in the destination countries, language, environment, out off that work permit problems are the major problems in both origin and destination place. To promote the rights of migrant’s worker is major issue in present time. Foreign labour migration sending the large amount of remittance of Nepal, but they have not been able to utilize in productive sectors.

A Deep Transfer NOx Emission Inversion Model of Diesel Vehicles with Multisource External Influence

By installing on-board diagnostics (OBD) on tested vehicles, the after-treatment exhaust emissions can be monitored in real time to construct driving cycle-based emission models, which can provide data support for the construction of dynamic emission inventories of mobile source emission. However, in actual vehicle emission detection systems, due to the equipment installation costs and differences in vehicle driving conditions, engine operating conditions, and driving behavior patterns, it is impossible to ensure that the emission monitoring data of different vehicles always follow the same distribution. The traditional machine learning emission model usually assumes that the training set and test set of emission test data are derived from the same data distribution, and a unified emission model is used for estimation of different types of vehicles, ignoring the difference in monitoring data distribution. In this study, we attempt to build a diesel vehicle NOx emission prediction model based on the deep transfer learning framework with a few emission monitoring data. The proposed model firstly uses Spearman correlation analysis and Lasso feature selection to accomplish the selection of factors with high correlation with NOx emission from multiple sources of external factors. Then, the stacked sparse AutoEncoder is used to map different vehicle working condition emission data into the same feature space, and then, the distribution alignment of different vehicle working condition emission data features is achieved by minimizing maximum mean discrepancy (MMD) in the feature space. Finally, we validated the proposed method with the diesel vehicle OBD data that were collected by the Hefei Environmental Protection Bureau. The comprehensive experiment results show that our method can achieve the feature distribution alignment of emission data under different vehicle working conditions and improve the prediction performance of the NOx inversion model given a little amount of NOx emission monitoring data.

Development of Model of Proactive Management of Refineries' Equipment Restoration

The article considers the topic of maintenance of equipment in a working condition in the activities of oil producing enterprises. The exploitation of the means of labor takes place in difficult mining, geological and climatic conditions. Ensuring the reliability and efficiency of the surface and underground equipment operation is a priority task for the oil producing enterprises of the Russian Federation. In modern economic conditions, there is a need to improve the efficiency of work on the restoration of equipment.

Optimization and realization on the coordination control strategy for auxiliary power unit of range-extended electric vehicle

The auxiliary power unit (APU) is a major power source of range-extended electric vehicle (R-EEV). Excellent coordination control strategy of APU has a great significance impact on improving the overall electrical control system performance of R-EEV. A coordination control strategy based on parameters adapt fuzzy-PID is proposed to ensure the dynamic and static response characteristics of the coordination control system. Firstly, the APU high precision simulation control model is built in GT-Power and Matlab-Simulink. Three coordination control strategies based on traditional PID control method are designed, namely, engine speed control model (ESCM), generator torque control model (GTCM), and APU speed-torque control model (AS-TCM). The three coordination control strategies are simulated on working conditions, which include start-up working condition, power raised working condition, and power reduced working condition. Combined with the PID control principle, the control performance and inherent limitations of three traditional PID control strategies (TPCS) are analyzed and compared. Then, according to the above simulation results of analysis and comparation, the parameters adapt fuzzy-PID control strategy (PAF-PCS) is designed and simulated. The results show that three control parameters ( kp, ki, kd) are changed in real time to ensure the flexibility and adaptability of the control system and improve the stability and robustness of control system. Finally, the results of bench test show that power responds quickly and no oscillation and fixed-point power generation works smoothly, which are basically consistent with the simulation results. Therefore, the PAF-PCS proposed in this paper has good feasibility and effectiveness.