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This study aims to examine the problems encountered during the establishment of the Central Police Academy (CPA) under the Nationalist regime from 1936 to 1949. While the authoritarian party-state unified the police academies by forceful means, this catalyzed the cleavage between the schools of police studies and resulted in power struggles over police education, intellectual thought, collectivity and even the national reform of police administration. More than narrating the progress of power consolidation, this study attempts to identify the problems underlying the factional strife and to reveal the interwoven pattern of these power struggles, exploring the confusion regarding what the police is, a question that troubled Chinese policemen from the mainland to Taiwan.

This paper explains the emergence of the factional strife from the beginning of the preliminary growth of the Police Academies in Nanking and Chekiang. It widely makes use of the official archives from Japan Center for Asian Historical Records and Historica Academia to show the dynamic situation in police education and administration. Rather, the official publications of the Police Academies and their affiliated associations reveal the hidden political agenda behind a unified framework as the party-state claimed. Moreover, official gazettes, memorials and newspapers are also used to strengthen the core argument of this study.

This paper examines the impact of the factional strife between the police leaders Dai Li and Li Shizhen on the CPA from 1936 to 1949. It illustrates that the establishment of the CPA ostensibly unified the nationwide police force but triggered power struggles over the control of the police administration. More importantly, it also shows how the factions strove for larger shares of power under the supreme doctrines that Chiang Kai-shek and the party-state imposed.

The failure of police education to become powerful was a special case among other more typical institutions. The governors coercively merged the police academies and created robust conditions for growth under the shelter of state authority. The police force did not follow the same path of national monopoly as what recent studies found but drifted apart with its vested interests and incompatible beliefs. Hence, the greater the demand for centralized control by the state, the greater the tension of the factional strife.

This paper aims to present a method based on dynamics to find the transient pressure at the nozzle area of a piezoelectric inkjet printer. This pressure responds to input signals of the piezoelectric driver deformation. The pressure at the nozzle is the boundary condition of the computational fluid dynamics model of the inkjet printer nozzle, and serves as the “bridge” between the piezoelectric driver actuation and the droplet generation of an inkjet printer.

The transient pressure was estimated using a fluid-solid coupling numerical model of the printerhead. In this study, a simple step-shape signal was applied. The printerhead chamber was considered to act as a linear Helmholtz resonator to determine the system transfer function between the input of driver deformation and the output of pressure. By decomposing the input signal into several simple signals, the transient pressure is the superposition of those calculated pressures.

The pressure values determined by transfer function and by superposition match the pressure values directly calculated by a fluid-solid coupling model. This demonstrates the rationality and practicability of the method.

This paper proposes a method to identify a proper boundary condition of pressure for numerical models that only include the fluid field around the nozzle. This strategy eliminates the need to calculate the complex and unstable fluid-solid coupling for every pattern of input. Additionally, the suitable boundary condition of transient pressure can be set rather than relying on the shape of the PZT driver deformation signal.

The purpose of this paper is to design a lightweight tree-shaped internal support structure for fused deposition modeling (FDM) three-dimensional (3D) printed shell models.

A hybrid of an improved particle swarm optimization (PSO) and greedy strategy is proposed to address the topology optimization of the tree-shaped support structures, where the improved PSO is different from traditional PSO by integrating the best component of different particles into the global best particle. In addition, different from FEM-based methods, the growing of tree branches is based on a large set of FDM 3D printing experiments.

The proposed improved PSO and its combination with a greedy strategy is effective in reducing the volume of the tree-shaped support structures. Through comparison experiments, it is shown that the results of the proposed method outperform the results of recent works.

The proposed approach requires the derivation of the function of the yield length of a branch in terms of a set of critical parameters (printing speed, layer thickness, materials, etc.), which is to be used in growing the tree branches. This process requires a large number of printing experiments. To speed up this process, the users can print a dozen of branches on a single build platform. Thereafter, the users can always use the function for the fabrication of the 3D models.

The proposed approach is useful for the designers and manufacturers to save materials and printing time in fabricating the shell models using the FDM technique; although the target is to minimize the volume of internal support structures, it is also applicable to the exterior support structures, and it can be adapted to the design of the tree-shaped support structures for other AM techniques such as SLA and SLM.

This paper aims to present an optimization method of the input driving signal of a piezoelectric inkjet printhead to improve droplet consistency and increase jetting frequency.

The optimization target is the transient pressure in the nozzle caused by the input driving signal, which directly generates the droplets. After demonstrating the linearity of the driving input and system pressure, an analytic model as a transfer function was developed, allowing calculation of the pressure vibration in the nozzle for an arbitrary input. Different patterns of input signal were parameterized and applied into the optimizing function, which represents the difference between the ideal and the actual pressure vibration. By determining the function minimum, the optimized parameters of the input signal were estimated.

Optimization results of different input patterns were compared and verified by the numerical model of the printhead, and it was revealed that the optimization method that combined the quenching pulse and an increased falling time interval was more effective than use of a single method.

After the process of optimization, a new type of input signal to the piezoelectric inkjet printhead was showed. By this method, the frequency of the printhead could be increased without losing consistency of droplets.

The purpose of this paper is to propose a template‐based framework for nasal prosthesis fabrication using a 3D areal scanner and a CT scanner.

Use of a self‐designed 3D areal scanner enables acquisition of accurate data describing the patient's face. Patients with nasal defects have no organization for reference, but the template‐based model construction method can ensure successful building of the outer surface of the nasal prosthesis. Since the areal scanner has some difficulties acquiring data for concave areas, preoperative CT data are used to provide concave information, enabling construction of the inner surface for the nasal prosthesis. The combined inner and outer surfaces are used to generate the completed nasal prosthesis.

The results showed that the nasal prosthesis fits the patient's appearance well. Clinical applications confirmed that this framework is attractive and has the potential desired nasal prosthesis in daily clinical practice.

The results of this study improve the fabrication accuracy of nasal prostheses. The construction and development technique employs a nasal digital library, 3D areal scanning data and CT scanning data. This technique facilitates fabrication of precise nasal prostheses while helping the patients predict the effect before the prosthesis is manufactured.

This template‐based framework has strong potential for clinical applications because of its advantages over other methods in terms of accuracy, speed, safety, and cost.

The purpose of this paper is to propose an imperfect symmetry transform framework for orbital prosthesis modelling.

Current models of patients with orbital defects have imperfect symmetries. Commonly used methods, such as principal component analysis (PCA) or iterative closest points algorithm (ICP), do not detect perfect symmetries and therefore produce poor results. The authors propose an improved ICP algorithm based on the M‐estimator, which can remove outliers from the optimization and detect incorrect symmetry. Using this algorithm, the mid‐facial plane of a patient's facial model can be precisely obtained despite perturbation of the facial shape due to the defect.

The results showed that the orbital prosthesis fitted well to the patient's appearance. Clinical applications confirmed that this framework is attractive and has the potential for use in creating desired orbital prostheses or other bilateral maxillofacial prostheses in daily clinical practice.

The method described in this report will improve the fabrication accuracy of orbital prostheses or other bilateral maxillofacial prostheses.

This imperfect symmetry transform framework has great potential for use in clinical applications because of its advantages over other existing methods in terms of accuracy.

The purpose of this paper is to describe a processing system for 3D dress geometry modelling and texture mapping.

Since the range image and its corresponding texture from one direction could be acquired by areal 3D scanner simultaneously, the texture can be integrated into the range image exactly. In the geometry modelling stage, the graph‐based algorithm is used for multi‐view registration. In order to enhance its robustness, a method for judging bad pairwise registration is proposed based on the computation of two views' overlapping percentage. In order to enrich its completeness, combined the graph analysis with the metaview method is used to deal with the measurement data for local details. In the texture mapping stage, based on grid search structure, the method of solving the Poisson equation for the colour field that best fits the colour gradients can produce a seamlessly textured surface quickly.

Results show that the processing system can provide a 3D textured dress geometry model with no seams and low distortion successfully.

The processing system can provide an accurate 3D dress geometry model, which can be used to modify the further design or virtual try.

A 3D dress geometry model with no seams and low distortion provides the fashion designer with not only the visual effects, but also accurate data used for design modification.

The purpose of this paper is to propose a universal, robust and efficient method to obtain a reliable initial guess solution for the one‐step finite element simulation.

In one‐step simulation, getting initial guess solutions effectively is essential to ensure the success of the non‐linear resolution in the implicit static solver and to speed up the convergence of the Newton‐Raphson iterations. A newly emerging mesh parameterization approach named As‐Rigid‐As‐Possible method, which is widely used in computer graphics, is proposed as an effective initial guess estimation method in this paper. It is almost an isometric parameterization and showing excellent area‐preserving capability than other state‐of‐the‐art approaches. Several numerical examples are provided to verify the validity and efficiency of the presented method.

Compared with the geometry mapping methods, the presented ARAP method shows its universality in handling types of workpieces whether they have quasi‐vertical walls or they are long and complicated. Complex 3D workpieces with many local convex and concave features can also be well handled without large element shape distortions. In contrast to the energy based mapping algorithm, the method presented in this paper does not need to predefine the boundary nodes which will introduce less distortion to the elements near the boundary.

This paper is the first to utilize the As‐Rigid‐As‐Possible mesh parameterization algorithm to obtain an initial guess for the one‐step simulation. The numerical experiments show that the approach is universal, robust and efficient and can be further utilized in the optimum blank design or blank shape optimization.

The purpose of this paper is to describe a computer‐aided design/manufacturing (CAD/CAM) system for fabricating facial prostheses.

The CAD/CAM system can be used for fabricating custom‐made facial prostheses with symmetrical or asymmetrical features. This system integrates non‐contact structured light scanning, reverse engineering and rapid prototyping manufacturing technology. Fringe projection based on the combination of the phase‐shift and grey‐code methods is used for data collection. A robust approach is proposed to calculate the mid‐plane of the human face without any knowledge of the centroid position or the principal axis in data processing.

Results show that the proposed method increases the fabrication accuracy and reduces the operating time. Patients were satisfied with the rehabilitation results as the custom‐made facial prostheses fitted them well.

This study improves the fabrication accuracy of facial prostheses. Three‐dimensional data of the facial surface of a patient needing a facial prosthesis were obtained with almost no harm to his body; after a series of robust processes, a precise and suitable aesthetic facial prosthesis was fabricated.

This system has bright prospects for clinical application because of its advantages over other methods in terms of speed, accuracy, safety, cost, etc.

The purpose of this paper is to estimate aerodynamic parameters accurately from flight data in the presence of unknown noise characteristics.

The introduced adaptive filter scheme is composed of two parallel UKFs. At every time‐step, the master UKF estimates the states and parameters using the noise covariance obtained by the slave UKF, while the slave UKF estimates the noise covariance using the innovations generated by the master UKF. This real time innovation‐based adaptive unscented Kalman filter (UKF) is used to estimate aerodynamic parameters of aircraft in uncertain environment where noise characteristics are drastically changing.

The investigations are initially made on simulated flight data with moderate to high level of process noise and it is shown that all the aerodynamic parameter estimates are accurate. Results are analyzed based on Monte Carlo simulation with 4000 realizations. The efficacy of adaptive UKF in comparison with the other standard Kalman filters on the estimation of accurate flight stability and control derivatives from flight test data in the presence of noise, are also evaluated. It is found that adaptive UKF successfully attains better aerodynamic parameter estimation under the same condition of process noise intensity changes.

The presence of process noise complicates parameter estimation severely. Since the non‐measurable process noise makes the system stochastic, consequently, it requires a suitable state estimator to propagate the states for online estimation of aircraft aerodynamic parameters from flight data.

This is the first paper highlighting the process noise intensity change on real time estimation of flight stability and control parameters using adaptive unscented Kalman filter.