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This paper aims to investigate the effect of ultrasonic vibration (USV) on the evolution of intermetallic compounds (IMCs), grain morphology and shear strength of soldered Ni/Sn/Ni samples.

The Ni/Sn/Ni joints were obtained through ultrasonic-assisted soldering. The formation of IMCs, their composition, grain morphology and the fractured-surface microstructures from shear tests were characterized using scanning electron microscopy and energy-dispersive x-ray spectroscopy.

Without USV, a planar interfacial Ni₃Sn₄ layer was formed at the Ni/Sn interface, and a few Ni₃Sn₄ grains were distributed in the soldered joint. The morphology of these grains was needle-shaped. With USV, several grooves were formed at the interfacial Ni₃Sn₄ layer due to ultrasonic cavitation. Some deepened grooves led to “neck” connections at the roots of the Ni₃Sn₄ grains, which accelerated the strong detachment of Ni₃Sn₄ from the substrate. In addition, two types of Ni₃Sn₄ grains, needle-shaped and granular-shaped, were observed at the interface. Furthermore, the shear strength increased with longer USV time, which was attributed to the thinning of the interfacial IMC layers and dispersion strengthening from the Ni₃Sn₄ particles distributed evenly in the joint.

The novelty of the paper is the detailed study of the effect of USV on the morphology, size changes of interfacial IMC and joint strength. This provides guidance for the application of ultrasonic-assisted soldering in electronics packaging.

This study aims to solder AlN ceramics with a Cu substrate using an active type Sn-Ag-Ti solder. Soldering was performed with power ultrasound. The Sn3.5Ag2Ti alloy was first studied.

It was found to contain a Sn matrix, where both Ag phase – ɛ-Ag₃Sn – and Ti phases ɛ-Ti₆Sn₅ and Ti₂Sn₃ – were identified. Ti contained in these phases is distributed to the interface with ceramic material. A reaction layer was thus formed. This layer varies in thickness from 0.5 to 3.5 µm and ensures the wettability of an active solder on the surfaces of ceramic materials.

X-ray diffraction analysis proved the presence of new NTi and AlTi₂ phases on the fractured surface. Sn plays the main role in bond formation when soldering the Cu substrate with Sn-Ag-Ti solder. The Cu₃Sn and Cu₆Sn₅ phases, which grow in direction from the phase interface to solder matrix, were found in all cases within the solder/Cu substrate interface. The combination of AlN ceramics/Cu joint maintained a shear strength of 29.5 MPa, whereas the Cu/Cu joint showed a somewhat higher shear strength of 39.5 MPa.

The present study was oriented towards soldering of AlN ceramics with a Cu substrate by the aid of ultrasound, and the fluxless soldering method was applied. Soldering alloy type Sn-Ag-Ti was analysed, and the interactions between the solder and ceramic and/or Cu substrate were studied. The shear strength of fabricated soldered joints was measured.

The purpose of this study is to understand the effect of different brand positions (underdog vs top dog) and comparative advertising on consumers’ brand attitudes. Additionally, this study also aims to demonstrate the effects of inspiration, self-relevance and empathy on the relationship between brand positioning and comparative advertising.

A two-by-three factorial design was employed with brand positions (underdog vs top dog) and three types of comparative advertising (noncomparative, indirect comparative and direct comparative) as the independent variables. Inspiration serves as the mediator, while self-relevance and empathy act as moderators and brand attitude is the dependent variable.

The results show that different brand positions significantly affect brand attitudes, with respondents having a better brand attitude toward the underdog brand. Brand attitude is partially mediated by inspiration. Self-relevance moderates the relationship between brand positioning and brand attitude. However, brand positioning, comparative advertising and empathy do not have interaction effects.

This study contributes to a better understanding of the effect of psychological variables on brand positioning and comparative advertising.

The results suggest that the underdog setting requires a real and honest story because consumers will spot a fake underdog story, which will damage consumer trust in the brand and harm the brand image.

There is a lack of research using psychological variables to demonstrate the effect of being the underdog brand. This study contributes to the literature by employing psychological variables to illustrate the effect of underdog positioning. These findings can help brands develop branding positioning strategies.

The paper aims to provide an overview of the area of digital pattern developing for customized apparel.

The paper outlines several methods of digital pattern developing for customized apparel, and discusses the principles, characters and applications. Digital pattern developing process has two paths. One path develops apparel according to traditional 2D pattern‐making technology. There are three methods: parametric design, traditional grading technique, and pattern generating based on artificial intelligence (AI). Another path develops pattern through surface flattening directly from individual 3D apparel model.

For parametric method, it can improve greatly the efficiency of pattern design or pattern alteration. However, the development and application of parametric Computer‐Aided‐Design (CAD) systems in apparel industry are difficult, because apparel pattern has fewer laws in graphical structure. For grading technique, it is the most practical method because of its simple theory, with which pattern masters are familiar. But these methods require users with higher experience. Creating expert pattern system based on AI can reduce the experience requirements. Meanwhile, a great deal of experiments should be conducted for each garment with different style to create their knowledge databases. For 3D CAD technology, two methods of surface flattening have been outlined, namely geometry flattening and physical flattening. But many improvements should be done if the 3D CAD systems are applied in apparel mass customization.

The paper provides information of value to the future research on developing a practical made‐to‐measure apparel pattern system.

The purpose of this paper is to provide a theoretical model for considering ease numerically in the clothing pattern. Classifying the pattern as a geometric Cartesian coordinate system, this model proposes the need to quantify the partly coincident variables of ease, which will enable greater control over garment fit and function, using traditional or CAD/CAM methods.

The principles of pattern/garment dimensions are considered with support from analysis of literature and contributing factors to the variables of ease are categorised. These principles support a proposed theoretical model for considering pattern/garment dimensions, in the numeric format that they exist within the context of pattern construction.

Pattern construction occurs in a 2D Cartesian coordinate system, guided by body dimensions and ease. This can be modelled in the form of an algorithm relating to the placement of cardinal points defining the pattern outline. Recognition of the numerical nature of the pattern, suggests the need to quantify the coincident variables of ease, to achieve greater control over garment fit and function.

Few sources exist enabling the recognition of ease requirements in the pattern/garment and when guidance on ease is presented, there is little rationale as to how it has been established, or what contributes to its definition.

The paper shows how current methods of pattern construction can be modelled more effectively, recognising the geometric nature on which they are based. Modelling these relationships highlights where quantification can be provided, by existing knowledge or future research.

The purpose of this paper is to propose a relatively simple and rapid method to create a digital human model (DHM) to serve clothing industry.

Human body’s point cloud is divided into hands, foots, head and torso. Then forward modeling method is used to model hands and foots, photo modeling method is used to model head and reverse modeling method is used to model torso. After that, hands, foots, head and torso are integrated together to get a static avatar. Next, virtual skeleton is bound to the avatar. Finally, a lifelike digital human body model is created by the mixed modeling method (MMM).

In allusion to the defect of the three-dimension original data of human body, this paper presented an MMM, with which we can get a realistic digital human body model with accurate body dimensions. The DHM can well meet the needs of fashion industry.

The DHM, which is got by the MMM, can be well applied in the field of virtual try on, virtual fashion design, virtual fashion show and so on.

The originality of the paper lies in the integration of forward modeling, reverse modeling and photo modeling to present a novel method of human body modeling.

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.

The main issue in the mass customization of apparel products is how to efficiently produce products of various sizes. A parametric pattern-making system is one of the notable ways to rectify this issue, but there is a lack of information on the parametric design itself and its application to the apparel industry. This study compares and analyzes three types of parametric clothing pattern CAD (P-CAD) software currently in use to identify the characteristics of each, and suggest a basic guideline for efficient and adaptable P-CAD software in the apparel industry.

This study compared three different types of P-CAD software with different characteristics: SuperALPHA: PLUS(as known as YUKA), GRAFIS and Seamly2D. The authors analyzed the types and management methodologies of each software, according to the three essential components that refer to previous studies about parametric design systems: entities, constraints and parameters.

The results demonstrated the advantages and disadvantages of methodology in terms of three essential components of each software. Based on the results, the authors proposed five strategies for P-CAD development that can be applied to the mass customization of clothing.

This study is meaningful in that it consolidates and organizes information about P-CAD software that has previously been scattered. The framework used in this study has an academic value suggesting guidelines to analyze P-CAD systems.

The purpose of this paper is to find the pattern with minimal deformation energy while developing from 3D designed garments. Moreover, darts are generated to further reduce deformation energy. The aims of the energy-based flattening method are to reduce the difference between 3D designed garments and 2D flattened patterns in an accurate and efficient way.

This study uses a mass spring method and iterative optimization to analyze pattern contours with minimal contour deformation while flattening three dimensional draping designs into a plane. Darts are generated to further reduce distortion during surface flattening and the energy method is introduced to verify that the analysis results obtained match the garment darts provided by the Bunka formula which is currently widely used in East Asia.

An efficient method for generating optimal darted pattern is presented. It compares the important factors of darts, including position, length and amount. After iterative optimization and darts generation, the maximum energy reduction is about 30 percent.

This study provides an aggregate to analyze and compare the differences between different patterns and conduct a verification comparison with traditional pattern formula.

Low levels of human capital in rural China are rooted in the poor schooling outcomes of elementary school students. The purpose of this paper is to provide insight into the distribution of academic performance in rural China and identify vulnerable groups.

The authors draw on a data set of 25,892 observations constructed from 11 school-level surveys spanning nine provinces and one municipality in China conducted from 2013 to 2015.

The authors find that the distribution of academic performance is uneven across provinces and subgroups. In general, male students, Han, living in richer counties, living with their parents and studying in rural public schools do better academically than female students, non-Han, living in poorer counties, left behind and studying in private migrant schools in cities.

Using the results of this study, policymakers should be able to better target investments into rural education focusing on at risk subpopulations.

With limited data sources, the research on the academic performance of students in rural China is largely absent. The findings of this study help to fill the gaps in the literature base.