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The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

Considers the factors which influence Taiwanese decisions to buy Japanese or US refrigerators, basing the conclusions on the results of a survey of 586 respondents drawn from Taiwan’s four largest cities – Taipei, Kaoshiung, Taichung and Tainan. Describes how the questionnaires were constructed and pretested, and explains how the data was recorded (using a 5‐point Likert‐type scale) and analysed (using factor analysis and t‐tests). Tests particularly for cultural values of the Chinese, consumer ethnocentrism, openness to foreign culture, country image, and consumer sophistication. Finds that, despite the longer presence of Japanese goods in Taiwan, Japan’s proximity to Taiwan, and more cultural similarities between the Japanese and Taiwanese, Taiwanese consumers rate the USA’s country image factor higher than Japan’s, with consequent implications regarding intention to buy US goods. Recommends that US marketers build on their advantageous country image when they promote US appliances in foreign markets. Cautions against making too much of this snapshot data but concedes that further research into different foreign markets, different appliances, and with a longitudinal approach, would ascertain if findings are consistent with this survey, which has obvious benefits as new markets, such as China and India, open up to western goods and appliances.

Notes that cellular is the inevitable future architecture for the personal communication service system (PCS). This is important for wireless mobile communications and will eventually be integrated with the Internet. Recent initiatives to add mobility to the Internet and packet data services for the next generation cellular systems are being considered by many mobile service providers, and providing a seamless support for IP‐based packet switched services is an important issue. Mobile Internet Protocol version 6 (Ipv6) is a new version of the Internet Protocol that was standardized by the Internet Engineering Task Force (IETF). It supports mobility and is presently being standardized by the IETF Mobile IP Working Group. Discusses the current cellular support based on Ipv6 and points out the shortfalls of using Mobile IP. Highlights protocols especially for mobile management schemes which can optimize a high speed mobile station moving among small wireless cells.

This paper aims to verify weather atmospheric plasma spray (APS) in situ remelting posttreatment is effective for densifying the porous FeCoCrMoCBY amorphous alloy (FAA) coating and improving the antiabrasion and anticorrosion performances or not.

APS was used to deposit and in situ densify FAA coating on the 40Cr substrate. Scanning electron microscope, X-ray diffractometer, energy dispersive spectroscopy, neutral salt spray, hardness and wear behavior test were used to evaluate the densifying effects.

APS remelting technology can effectively improve the hardness of the coating by reducing the porosity. After remelting at 30 kW power, the hardness of the coating increased by about 260 HV0.2 and the porosity decreased to 2.78%. The amorphous content of the coating is 93.9%, which is about 3.5% lower than original powders. The electrochemical impedance spectrum and neutral salt spray test results show that APS remelting can reduce the corrosion rate by about 62.7%.

APS remelting method is firstly proposed in this work to replace laser remelting or laser cladding methods. APS remelting method can effectively improve the corrosion and abrasion resistance of the FAA coating by increasing the densification with much low recrystallization, which is big progress for application of FAA coatings.

The purpose of this paper is agile attitude control design with the novel three-dimensional (3D) magnetically suspended wheel (MSW) that is the preferred type for agile maneuvering compared to conventional control moment gyro due to frictionless, low vibration and long lifetime. This system does not require a separate steering law for pyramid arrangement to derive tilt angles. It is also conducting an agile maneuver with high accuracy despite the high-frequency disturbances.

In this paper, a disturbance observer-based attitude stabilization method is proposed for an agile satellite with a pyramid cluster of the novel 3D magnetically suspended wheel actuator. This strategy includes a disturbance observer and a linear quadratic regulator controller. The rotor shaft deflection of MSW is actively controlled to reduce vibration and producing gyro torque. The deflection angle of the pyramid cluster MSWs considered as control parameters. The closed-loop stability is proved by using the Lyapunov strategy. The efficiency and performance of the offered method verified by numerical simulation via MATLAB/SIMULINK software.

According to simulation results, the disturbance observer-based control controller stabilized the system with high accuracy and optimal tilt angles without any extra steering law equation. Hence, the system speed is increased, and the system error is minimized without separate steering law.

The magnetically suspended wheel is a new kind of inertia actuator for attitude control that has several benefits such as frictionless, high-speed rotor, clean environment and low vibration compared to the traditional wheel. It has complex nonlinear dynamics that cause have complicated controller design. The proposed strategy stabilizes the system and conducting an agile maneuver with high precision despite the high-frequency disturbances. It is applicable for some missions requiring high accuracies, like Earth observation and the solar observation mission that require a very accurate pointing control and a long lifetime.

This paper is the initial paper to design a pyramid array for magnetically suspended wheels. Compared to other research, this method doesn’t need a separate steering law of the MSWs cluster and presented optimal tilt angles with less computational. Also, it designs a disturbance observer-based controller for this system that proposed high accuracy and agile stabilization.

This study is set out to assess the country of origin effect on Turkish consumption practices in order to provide a richer context for its formation process.

The research is exploratory and interpretative in nature. It follows a qualitative design with in-depth analysis of consumption experiences by utilizing semi-structured interviews.

The research shows that country of origin effect is product specific, and when it exists, it has an essential effect on product evaluations. It reveals that the country of origin effect is intrinsically constituted with the individual perceptions of and attitudes toward brands, countries, and past experiences, and it is extrinsically constituted with socially created perceptions by media, marketplace myths, and popularity.

This research investigated country of origin effect in a specific context of a developing country with a qualitative methodology. Unlike the existing literature, this study analyzes consumers’ actual purchase decisions in different product categories. Country of origin effect is found to be formed by individual and societal factors.

Multinational corporations (MNCs) are converging world cultures by creating common consumer lifestyles across countries through standardized products. However, little is known about how consumers’ exposure to foreign cultures affects their purchase experience from the country. This study explores this gap in the literature by investigating how consumers’ exposure to foreign cultural source (e.g., entertainment) shapes their attitude toward its country. This attitude is conceptualized to influence the perceived product quality and corporate ability of the country’s MNCs, which are further hypothesized to influence consumers’ purchase experience with products offered by the MNCs. Furthermore, the impact of product quality and corporate ability on consumer purchase experience is expected to be moderated by consumer ethnocentrism. The study framework is tested in the context of the Korean Wave (or “Hallyu”) using data consisting of 533 Indonesian consumers. The results support most of the study hypotheses. Theoretical and managerial implications of these findings are discussed.

Using an experimental design setting, this study investigates how global firms can make use of warranty strategies to influence consumers’ evaluations of hybrid products that are designed in one country and manufactured in another. The results confirm that consumers tend to perceive lower quality and higher purchase risk when evaluating products manufactured in a country perceived to be of lesser capability than its country of design (i.e., negative hybrid effects). However, global firms with products that carry such negative hybrid effects can develop appropriate warranty strategy to overcome such biases. For instance, the results show that consumers improve their assessment of the quality and purchase risk of the negative hybrid products when these products carry warranty with wider coverage and longer duration than the standard package, and when the firm providing the warranty has good warrantor reputation. Implications of these findings for international marketing and research are also discussed.

Semi-crystalline polymers such as polyamide-12 can be used for selective laser sintering (SLS) to make near-fully dense plastic parts. At present, however, the types of semi-crystalline polymers suitable for SLS are critically limited. Therefore, the purpose of this paper is to investigate the processibility of a new kind of semi-crystalline polypropylene (PP) with low isotacticity for SLS process.

The SLS processibility of the PP powder, including particle size and shape, sintering window, degree of crystallinity and degradation temperature, was evaluated. Effects of the applied laser energy density on the surface micromorphology, density, tensile strength and thermal properties of SLS-built PP specimens were studied.

The results show that the PP powder has a nearly spherical shape, smooth surfaces, an appropriate average particle size of 63.6 μm, a broad sintering window of 21 oC and low crystalline degree of 30.4 per cent comparable to that of polyamide-12, a high degradation temperature of 381.8°C and low part bed temperature of 105°C, indicating a very good SLS processibility. The density and the tensile strength first increase with increasing laser energy density until they reach the maximum values of 0.831 g/cm3 and 19.9 MPa, respectively, at the laser energy density of 0.0458 J/mm², and then decrease when the applied laser energy density continue to increase owing to the degradation of PP powders. The complex PP components have been manufactured by SLS using the optimum parameters, which are strong enough to be directly used as functional parts.

This paper provides a new knowledge for this field that low-isotacticity PPs exhibit good SLS processibility, therefore increasing material types and broadening the application of SLS technology.

Purpose – Extensive research in the area of consumer behavior has documented the “Country of Origin Effect,” which identifies country of origin as an important decision variable in evaluating products and services. Past research has mostly assumed that country of origin effect is driven by the performance of the products originating in that country. However, consumers can also form opinions about countries based on exposure to information that is unrelated to the product and may have roots in macro factors such as history, culture, and politics. These emotions, while extraneous to the product, can also influence product evaluations along with performance-related country information.Design/methodology/approach – This review examines research addressing both performance and emotional perceptions related to country of origin.Findings – This review presents an integrating framework termed “Nation Equity” to systematically understand and examine the influence of various dimensions of country of origin on consumer decision making.