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The market equilibrium model predicts that the supply and demand schedules of labor to an industry will cross at a level at which labor receives the value of its marginal product as contributed to the output produced. The imposition of an effective minimum wage in that industry creates a price floor for labor which will reduce employment as it promotes incentives to substitute capital for labor and/or workers with higher marginal productivity for those with lower skill and lower marginal productivity. This means in effect that it will lead employers to eliminate less productive jobs. Teenagers (youths 16–19 years old) with little training or work‐experience may be priced out of the market because they are not “worth” (in terms of productivity) the minimum wage.

This paper aims to elaborate in a greater detail about how to manage and eventually help resolve outstanding issues, including the core issue of Kashmir between nuclear India and Pakistan. In doing so, this paper elaborates various innovative measures that could be applicable to South Asian nuclear environment that in turn could assist the South Asian nuclear leadership in understanding and managing the fragility of South Asian nuclear deterrence.

Innovatively, this research paper looks at the South Asian nuclear issues at three levels of analysis – understanding the prevailing dynamics of nuclear revolution and improved means of communications and promoting deterrence stability in South Asia. All three levels may be more needed than ever before in the wake of the arrival of nuclear weapons for a broader Southern Asian region.

This paper finds out that although nuclear weapons have become a reality in South Asia and these deadly weapons have prevented major wars between India and Pakistan, nuclear weapons have not prevented the crises between India and Pakistan. Therefore, both India and Pakistan have confronted a number of crises. The paper finds out that any serious crisis between India and Pakistan could further undermine the credibility of existing confidence-building measures and the same could escalate from military to nuclear level. Absent from immediate measures undertaken by the South Asian security leadership, nuclear weapons may not help prevent the war between India and Pakistan at the sub-conventional level, this paper finds out.

By explaining innovative measures at the three level of analysis, this papers adds to the existing literature in understanding the behavior of South Asian security leadership and how these measures could best bring positive results in preventing a major crisis that potentially bears the risk of escalation to nuclear level.

This study aims to determine the minimum force required to pull out a surface mount component in printed circuit boards (PCBs) during the wave soldering process through both experimental and numerical procedures.

An efficient experimental technique was proposed to determine the minimum force required to pull out a surface mount component in PCBs during the wave soldering process.

The results showed that the pullout force is approximately 0.4 N. Comparing this value with the simulated force exerted by the solder wave on the component ( ≅ 0.001158 N), it can be concluded that the solder wave does not exert sufficient force to remove a component.

This study provides a deep understanding of the wave soldering process regarding the component pullout, a critical issue that usually occurs in the microelectronics industry during this soldering process. By applying both accurate experimental and numerical approaches, this study showed that more tests are needed to evaluate the main cause of this problem, as well as new insights were provided into the depositing process of glue dots on PCBs.

The purpose of this paper is to focus on the local minima issue encountered in motion planning by the artificial potential field (APF) method, investigate the currently existing approaches and analyze four types of previous methods. Based on the conclusions of analysis, this paper presents an improved wall‐following approach for real‐time application in mobile robots.

In the proposed method, new switching conditions among various behaviors are reasonably designed in order to guarantee the reliability and the generality of the method. In addition, path memory is incorporated in this method to enhance the robot's cognition capability to the environment. Therefore, the new method greatly weakens the blindness of decision making of robot and it is very helpful to select appropriate behaviors facing to the changeable situation. Comparing with the previous methods which are normally considering specific obstacles, the effectiveness of this proposed method for the environment with convex polygon‐shaped obstacles has been theoretically proved. The simulation and experimental results further demonstrate that the proposed method is adaptable for the environment with convex polygon‐shaped obstacles or non‐convex polygon‐shaped obstacles. It has more widely generality and adaptiveness than other existed methods in complicated unknown environment.

The proposed method can effectively realize real time motion planning with high reliability and generality. The cognition capability of mobile robot to the environment can be improved in order to adapt to the changeable situation. The proposed method can be suitable to more complex unknown environment. It is more applicable for actual environment comparing with other traditional APF methods.

This paper has widely investigated the currently existed approaches and analyzes deeply on four types of traditional APF methods adopted for real time motion planning in unknown environment with simulation works. Based on the conclusions of analysis, this paper presents an improved wall‐following approach. The proposed method can realize real time motion planning considering more complex environment with high reliability and generality. The simulation and experimental results further demonstrate that the proposed method is adaptable for the environment with convex polygon‐shaped obstacles or non‐convex polygon‐shaped obstacles. It has more widely generality and adaptiveness than other existed methods in complicated unknown environment.

The purpose is to predict the distribution of the residual pretightening force of the bolt group under the action of any initial pretightening force, and to achieve the final residual pretightening force as the target to solve the initial pretightening force value to be applied.

Based on the finite element method and the elastic interaction theory between bolt group, this paper establishes a prediction model for the residual pretightening force distribution of bolt group for one-step pretightening and multi-step pretightening of gasketless flange connection systems. In addition, using the general modeling method given in this paper, the prediction model of residual pretightening force of long plate bolt connection system is established, and compared with reference, which fully proves the effectiveness and universality of the general prediction model of residual pretightening force of bolt group.

The appropriate pretightening sequence, increasing the number of pretightening steps and variable amplitude loading can effectively reduce the influence of elastic interaction and improve the uniformity of residual pretightening force of the bolt group. And the selection of material, number of bolts and connected thickness of bolt connection system also has a great influence on the distribution of residual pretightening force of bolt groups.

The general prediction model for the residual pretightening force of bolt group of connecting structural components considering elastic interaction given in this paper can provide a reference for the design and optimization of the bolt assembly process of the rotor system and the casing system in aero-engine and the prediction of the performance of the connecting system.

Posture adjustment plays an important role in spacecraft manufacturing. The traditional posture adjustment method, which has a large workload and is difficult to guarantee the quality of posture adjustment, cannot meet the requirements of modern spacecraft manufacturing. This paper aims to optimize the trajectory of posture adjustment, reduce the internal force of the posture adjustment mechanism and improve the accuracy of the system.

First, the measuring point is measured by a laser tracker and the position and posture of the cabin is solved. Then, Newton–Euler method is used to construct the dynamic model of the posture adjustment system (PAS) without internal force. Finally, the adjustment time is optimized based on Fibonacci search method and the trajectory of the cabin is fitted by the fifth order polynomial.

The simulation results show that, compared with the other trajectory planning methods, this method can effectively avoid the internal force of posture adjustment caused by redundant driving, and the trajectory of velocity and acceleration obtained are continuous, meeting the engineering constraints.

In this paper, a dynamic model of PAS without internal force is constructed. The trajectory planning of posture adjustment based on this model can improve the quality of cabin assembly.

The purpose of this paper is to solve the common problems that traditional optimization methods cannot fully improve the performance of electromagnetic linear actuators (EMLAs).

In this paper, a multidisciplinary optimization (MDO) method based on the non-dominated sorting genetic algorithm-II (NSGA-II) algorithm was proposed. An electromagnetic-mechanical coupled actuator analysis model of EMLAs was established, and the coupling relationship between static/dynamic performance of the actuator was analyzed. Suitable optimization variables were designed based on fuzzy grayscale theory to address the incompleteness of the actuator data and the uncertainty of the coupling relationship. A multiobjective genetic algorithm was used to obtain the optimal solution set of Pareto with the maximum electromagnetic force, electromagnetic force fluctuation rate, time constant and efficiency as the optimization objectives, the final optimization results were then obtained through a multicriteria decision-making method.

The experimental results show that the maximum electromagnetic force, electromagnetic force fluctuation rate, time constants and efficiency are improved by 18.1%, 38.5%, 8.5% and 12%, respectively. Compared with single-discipline optimization, the effectiveness of the multidiscipline optimization method was verified.

This paper proposes a MDO method for EMLAs that takes into account static/dynamic performance, the proposed method is also applicable to the design and analysis of various electromagnetic actuators.

This chapter analyzes the effects of introducing a graduated minimum wage in a model with optimal income taxation in which a government seeks to maximize social welfare. It shows that the optimal graduated minimum wage increases social welfare by increasing the low-productivity workers’ consumption and bringing it closer to the first-best. The chapter also describes how the graduated minimum wage in a social welfare optimum depends on important economy characteristics such as the government’s revenue needs, the social welfare weight of low-productivity workers, and the numbers and productivities of the different types of workers.

Roller burnishing (RB) is a finishing treatment method that is used to impart certain physical and mechanical properties, such as surface roughness, improved visual appearance, or increased corrosion, friction, wear, and fatigue resistance. The purpose of this paper is to study, the influence of RB on corrosion resistance in A53 steel in HCl solution.

Microhardness (MH), microstructure, weight loss, and potentiostatic polarization are investigated at pressing forces of 40, 60, 80, 100 and 120 N.

MH increases with increasing the applied force and the percentage improvements are found to be 12, 24, 28, 35 and 65 percent for 40, 60, 80, 100 and 120 N RB pressing forces, respectively. Weight losses, in general, showed an optimum value at about 80 N. Corrosion potential and corrosion current decrease with increasing pressing force and reached a minimum at about 80 N, then begin to increase with increasing RB force.

The results present in this paper are important to the understanding of the effect of the surface plastic deformation methods on surface properties and corrosion resistance in steel.

The purpose of this paper is to describe the optimization of a permanent magnet linear actuator with soft magnetic mover for electromagnetic valve. The optimization is carried out with respect to the minimal magnetomotive force ensuring required minimum electromagnetic force on the mover.

Three optimization factors are employed. The value of the electromagnetic force and the objective function – the magnetomotive force – are obtained by caring out a full factorial design of experiment. For obtaining the objective function for each parameter combination, nonlinear equation is solved in order to minimize the flux that creates force in backward direction. Thus, several finite element analyses are carried out for each parameter combination. Then, response surface model is created and optimized. The obtained optimal solution is verified again by finite element analysis.

The paper finds that optimal actuator has been obtained and its force‐stroke characteristics and temperature distribution at steady‐state mode are given.

The valve is optimized by defining optimization function to be the solution of an equation canceling the flux in the nonactive part of the valve.