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Stopping and questioning citizens is an important policing tactic. Prior research explores citizens’ perceptions of stop and question policing, or “SQP”, by municipal police, yet campus police also use this tactic. The purpose of this paper is to understand whether and why college students believe campus police should have the right to engage in SQP.

Data come from 73 in-depth interviews with students attending a university in metropolitan Atlanta, GA. The sample was obtained through convenience and purposive sampling methods. Data were analyzed using the ethnographic perspective.

Most participants said campus police should practice SQP for three reasons: it is their job; SQP is an effective crime fighting tactic; and SQP is useful given the features and functions of college campuses. Among participants who said campus police should not practice SQP, they were concerned that officers would use it in unwarranted situations.

Findings suggest that the police might be able to reduce resistance to SQP by clearly explaining to suspects why they are being stopped and also clarifying to the public the legal thresholds for stopping and questioning citizens.

This is the first study to consider perceptions of SQP by campus police. The findings also shed light on how campus and municipal police are (dis)similar in perceptions of their SQP practices.

The purpose of this study is to investigate the links between lean, service quality expectation (SQE) and service quality performance (SQP) in outpatient departments (OPD).

The measurement instruments were developed from a comprehensive literature review, then verified by experts and confirmatory factor analysis. Multiple responses were applied to improve the reliability of data obtained from 220 Thai hospitals. The hypotheses were tested with linear regression and path analysis of structural equation modeling.

It was found that lean has significant positive impacts on all SQP dimensions (i.e. tangibility, reliability, responsiveness, assurance and empathy) and on overall SQP. SQE has significant positive direct effects on lean and SQP, and has a significant positive indirect effect on SQP through lean.

This is one of the first examples of research to present insights into the relationships between lean, SQE and SQP in OPD.

The time complexity of most multiple sequence alignment algorithm is O(N2) or O(N3) (N is the number of sequences). In addition, with the development of biotechnology, the amount of biological sequences grows significantly. The traditional methods have some difficulties in handling large-scale sequence. The proposed Lemk_MSA method aims to reduce the time complexity, especially for large-scale sequences. At the same time, it can keep similar accuracy level compared to the traditional methods.

LemK_MSA converts multiple sequence alignment into corresponding 10D vector alignment by ten types of copy modes based on Lempel-Ziv. Then, it uses k-means algorithm and NJ algorithm to divide the sequences into several groups and calculate guide tree of each group. A complete guide tree for multiple sequence alignment could be constructed by merging guide tree of every group. Moreover, for large-scale multiple sequence, Lemk_MSA proposes a GPU-based parallel way for distance matrix calculation.

Under this approach, the time efficiency to process multiple sequence alignment can be improved. The high-throughput mouse antibody sequences are used to validate the proposed method. Compared to ClustalW, MAFFT and Mbed, LemK_MSA is more than ten times efficient while ensuring the alignment accuracy at the same time.

This paper proposes a novel method with sequence vectorization for multiple sequence alignment based on Lempel-Ziv. A GPU-based parallel method has been designed for large-scale distance matrix calculation. It provides a new way for multiple sequence alignment research.

The purpose of this paper is to evaluate the worst-case behavior of a given electronic circuit by varying the values of the components in a meaningful way in order not to exceed pre-defined currents or voltages limits during a transient operation.

An analytic formulation is used to identify the time-dependent solution of voltages or currents using proper state equations in closed form. Circuits with linear elements can be described by a system of differential equations, while circuits composing nonlinear elements are described by piecewise-linear models. A sequential quadratic program (SQP) is used to find the worst-case scenario.

It is found that the worst-case scenario can be obtained with as few solutions to the forward problem as possible by applying an SQP method.

The SQP method in combination with the analytic forward solver approach shows that the worst-case limit converges in a few steps even if the worst-case limit is not on the boundary of the parameters.

The importance of international dry port integration in the supply chain has received a great deal of attention and been widely discussed in the literature. This study empirically examines the relationship among dry port logistics supply chain integration (DPLSCI), its operational performance (OP) and dry port competitiveness (DPC) in the context of China.

The authors developed a structured questionnaire based on the supply chain integration (SCI) theory and resource-based view, and collected data from the dry port operation enterprises and their stakeholders in central and western China. A structural equation model (SEM) is used to test the research hypotheses.

The results demonstrate that DPLSCI has a positive effect on logistics cost performance (LCP) and service quality performance (SQP), which further improves DPC. Meanwhile, OP (LCP and SQP) is a full mediator between DPLSCI and DPC.

This paper provides guidelines for dry port operators and their stakeholders to integrate supply chain resources and develop the OP for improving the overall competitiveness of an international dry port. The government could also invest in physical infrastructure and system platform to strengthen the OP of a dry port and further enhance its competitiveness.

The authors emphasise that the international dry port is a proactive and integrated system in providing a supply chain logistics service. This study fills up a research gap in the extant literature on theoretically proposing and empirically testing a new theoretical model. It also contributes to dry port stakeholders by providing useful guidelines to enhance OP and dry port competitiveness.

Static converters generate current harmonics in grids. Numerous studies on analytical frequency models of converters are often required to carry out their harmonic modeling in the context of sizing by optimization. Some formulations are proposed to solve such models. Each formulation has its own advantages and drawbacks. The paper mainly focuses on two formulations: the first to be solved by Sequential Quadratic Programming (SQP) and the second to be solved by Newton-Raphson (NR). In this way, the paper presents the performances of each formulation and compares the results of both formulations for the modeling of a single-phase diode rectifier.

The paper aims to compare SQP formulation and NR formulation, and to propose the ways to improve their convergence. In the modeling, by using an explicit formulation of the state variables combined to a numerical method, equations are defined to reduce, as far as possible, the number of unknowns.

The difficulty is to find the good operating mode of the static converter. So, outside the equations and the constraints, the paper proposes to use the eigenvalues of the state space matrixes to initialize the duration of every configuration and to consider the operating symmetries of the static converter that allow to reduce the research area and also the variables calculated.

The number of the conducting phase per half period is a priori, as the operating mode.

The modeling is based on the use of linear components, ideal switches and the static converter operates in steady-state. The main difficulties are to formulate the equations representing the non-controlled switching of semiconductors, and to solve them.

This investigation applied a hybrid method combining a trained artificial neural network (ANN) and the sequential quadratic programming (SQP) method to determine an optimal parameter setting for a reflow soldering process of ball grid array packages in printed circuit boards.

Nine experiments based on an orthogonal array table with three‐controlled inputs and average shear forces of solder spheres as a quality target were utilized to train the ANN and then the SQP method was implemented to search for an optimal setting of parameters.

The ANN can be utilized successfully to predict the shear force under different reflow soldering conditions after being properly trained and the identified optimal parameter setting are capable of striking the balance between the average shear forces and the manufacturing cycle time.

The reflow time and the peak temperature were found to be the most significant factors for the reflow process via analysis of variance.

This study provided an algorithm integrating a black‐box modeling approach (i.e. the ANN predictive model) with the SQP method to resolve an optimization problem. This algorithm offered an effective and systematic way to identify an optimal setting of the reflow soldering process. Hence, the efficiency of designing the optimal parameters was greatly improved.

Methods to optimize lattice structure design, such as ground structure optimization, have been shown to be useful when generating efficient design concepts with complex truss-like cellular structures. Unfortunately, designs suggested by lattice structure optimization methods are often infeasible because the obtained cross-sectional parameter values cannot be fabricated by additive manufacturing (AM) processes, and it is often very difficult to transform a design proposal into one that can be additively designed. This paper aims to propose an improved, two-phase lattice structure optimization framework that considers manufacturing constraints for the AM process.

The proposed framework uses a conventional ground structure optimization method in the first phase. In the second phase, the results from the ground structure optimization are modified according to the pre-determined manufacturing constraints using a second optimization procedure. To decrease the computational cost of the optimization process, an efficient gradient-based optimization algorithm, namely, the method of feasible directions (MFDs), is integrated into this framework. The developed framework is applied to three different design examples. The efficacy of the framework is compared to that of existing lattice structure optimization methods.

The proposed optimization framework provided designs more efficiently and with better performance than the existing optimization methods.

The proposed framework can be used effectively for optimizing complex lattice-based structures.

An improved optimization framework that efficiently considers the AM constraints was reported for the design of lattice-based structures.

This paper evaluates a Successive Response Surface Method (SRSM) specifically developed for simulation‐based design optimization, e.g. that of explicit nonlinear dynamics in crashworthiness design. Linear response surfaces are constructed in a subregion of the design space using a design of experiments approach with a D‐optimal experimental design. To converge to an optimum, a domain reduction scheme is utilized. The scheme requires only one user‐defined parameter, namely the size of the initial subregion. During optimization, the size of this region is adapted using a move reversal criterion to counter oscillation and a move distance criterion to gauge accuracy. To test its robustness, the results using the method are compared to SQP results of a selection of the well‐known Hock and Schittkowski problems. Although convergence to a small tolerance is slow when compared to SQP, the SRSM method does remarkably well for these sometimes pathological analytical problems. The second test concerns three engineering problems sampled from the nonlinear structural dynamics field to investigate the method's handling of numerical noise and non‐linearity. It is shown that, despite its simplicity, the SRSM method converges stably and is relatively insensitive to its only user‐required input parameter.

Considers, without loss of generality, a simple linear problem, where in a certain domain the magnetic field, generated by infinitely long conductors, whose locations as well as the currents are unknown, has to meet a certain figure. The problem is solved by applying hierarchical simulated annealing, which iteratively reduces the dimension of the search space to save computational cost. A Gauss‐Newton scheme, making use of analytical Jacobians, preceding a sequential quadratic program (SQP), will be applied as a second approach to tackle this severely ill‐posed problem. The results of these two techniques will be analyzed and discussed and some comments on future work will be given.