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The purpose of this study is to use the individual blade pitch control (IBC), reduce actively both the rotor hub vibratory loads and airframe vibration responses for the lift-offset compound helicopter at a high-speed flight condition.

The Sikorsky X2 technology demonstrator (X2TD) is used as the lift-offset compound helicopter. The X2TD lift-offset rotor is modelled and its rotor hub vibratory loads at a flight speed of 250 knots are predicted using a rotorcraft comprehensive analysis code, CAMRAD II, and the airframe structural dynamics is represented with a finite element analysis code, MSC.NASTRAN. When the propulsive trim methodology is applied for rotor trim, the best input condition for IBC using multiple harmonic inputs is searched to reduce the rotor vibration, while the rotor aerodynamic performance (the rotor effective lift-to-drag ratio) is improved or maintained at least. Finally, the reduction in airframe vibration responses is investigated when the best input condition for IBC with multiple harmonics is applied to the lift-offset rotor.

When the IBC with the single harmonic input using the 2/rev actuation frequency, amplitude of 2° and control phase angle of 120° (2P/2°/120°) is considered for X2TD rotor, the rotor vibration is reduced by about 26.37% only and the rotor effective lift-to-drag ratio increases slightly by 0.98%. When X2TD rotor uses the IBC with multiple harmonic inputs (2P/2°/45° + 5P/1°/90°), the rotor hub vibratory loads and airframe vibration responses are reduced by 44.69% and from 0.48 to 79.10%, respectively, while rotor effective lift-to-drag ratio is improved by 0.77%, as compared to the baseline without IBC.

This study is the first study to use the 2/rev actuation for IBC to the four-bladed lift-offset coaxial rotor and to investigate to obtain simultaneously the rotor vibration reduction, rotor performance improvement and airframe vibration reduction, using IBC with multiple harmonic inputs.

To provide a design guideline for an automotive electronic module in order to improve its reliability in elevated environmental environments as well as in vibration environments.

Wire looping profiles, gel heights, and effects of mechanical vibration on aluminium wire bond failures are studied. Natural frequencies of various wire profiles are evaluated and effects of gel heights on reliability of products are studied using stochastic finite element analyses. The frequency dependent properties of silicone gels used in electronic modules are characterized by the corn and plate test. An experiment was also conducted in order to confirm numerical results.

The present study shows that the gel plays an important role in wire bond failures and reliability of the product. The gel reduces the amplitude of vibration of electronic modules due to its damping characteristics. However, both analytic and experimental results indicate that the gel imposes extra weight on the wires and may induce stresses on heels.

In the future study, it is suggested that other gel materials should be studied since the properties of gel strongly depend on the frequency which will affect the fatigue behavior of bonding wires.

The findings can be used as general design guidelines for wire bonding for automotive electronic modules.

The results will be very useful to design bonding wires for automotive electronic modules.

The purpose of this paper is to propose an objective method for technology forecasting (TF). For the construction of the proposed model, the paper aims to consider new approaches to patent mapping and clustering. In addition, the paper aims to introduce a matrix map and K‐medoids clustering based on support vector clustering (KM‐SVC) for vacant TF.

TF is an important research and development (R&D) policy issue for both companies and government. Vacant TF is one of the key technological planning methods for improving the competitive power of firms and governments. In general, a forecasting process is facilitated subjectively based on the researcher's knowledge, resulting in unstable TF performance. In this paper, the authors forecast the vacant technology areas in a given technology field by analyzing patent documents and employing the proposed matrix map and KM‐SVC to forecast vacant technology areas in the management of technology (MOT).

The paper examines the vacant technology areas for MOT patent documents from the USA, Europe, and China by comparing these countries in terms of technology trends in MOT and identifying the vacant technology areas by country. The matrix map provides broad vacant technology areas, whereas KM‐SVC provides more specific vacant technology areas. Thus, the paper identifies the vacant technology areas of a given technology field by using the results for both the matrix map and KM‐SVC.

The authors use patent documents as objective data to develop a model for vacant TF. The paper attempts to objectively forecast the vacant technology areas in a given technology field. To verify the performance of the matrix map and KM‐SVC, the authors conduct an experiment using patent documents related to MOT (the given technology field in this paper). The results suggest that the proposed forecasting model can be applied to diverse technology fields, including R&D management, technology marketing, and intellectual property management.

Most TF models are based on qualitative and subjective methods such as Delphi. That is, there are few objective models. In this regard, this paper proposes a quantitative and objective TF model that employs patent documents as objective data and a matrix map and KM‐SVC as quantitative methods.

Apple is a representative company of technological innovation (TI) and management. It has launched new and innovative products since 1977, and many companies and business schools around the world have attempted to learn about the success story of Apple's innovation. However, most previous research works on Apple's innovation have been based on qualitative approaches such as experts' opinions. Such studies offer a subjective point of view. By contrast, in this paper the authors aim to study the TI and forecasting of Apple by analyzing its patent applications, which is an objective approach to examining the innovation of Apple from a technological perspective.

TI is an important issue concerning technology management for companies and governments. To examine Apple's TI, the authors analyze all applied patents and construct analytical models according to three approaches. First, they build statistical models using the time series regression and multiple linear regression methods to create a technology map. Second, they cluster all Apple's patents to find its vacant technology domain. Lastly, they use social network analysis to search for technologies central to Apple's future.

The authors' study shows the technological trends and relations between Apple's technologies. This research finds vacant technology areas and central technologies for Apple's TI.

Using statistical and machine learning methods, the authors analyze all Apple's patents in order to predict the firm's future technologies. This research contributes to examining the TI of Apple. Therefore, the results of the patent analysis can highlight the technological opportunities for Apple's TI.

Traditional TI models have been based on qualitative methods. Previous investigations of Apple's TI have also relied on traditional analytical approaches. In this paper, however, the authors develop a quantitative and objective approach for examining Apple's TI.

This paper aims to determine the extent to which employees’ experiences of acoustic comfort, well-being and productivity in open-plan offices are determined by specific characteristics (including demographic information, task characteristics, and personality traits).

A questionnaire was distributed to the occupants of three open-plan office sites and was completed by 166 employees in total.

The results indicated that acoustic comfort in open-plan offices is largely determined by noise sensitivity. Higher noise sensitivity was associated with more negative ratings of acoustical quality, more perceived disturbance by speech and more difficulties in concentration. More negative experiences were also reported by employees with lower interactivity with colleagues.

There is significant inter-individual variability in experiences of acoustic comfort, well-being and productivity in open-plan offices. As such, workplace practitioners should consider acoustic and behavioural solutions for introducing a greater diversity of functional workspaces within the office, so that employees can choose the most suitable working area for their requirements.

Whereas the majority of past acoustics research has been laboratory-based, this study is conducted in real office environments with a representative sample of knowledge workers.

With the increasing dependence on market-based distribution of health-care resources in the USA, spending on health-care service advertisements directly targeting consumers has also increased. Previous research has shown that the ads fail to deliver information deemed essential by regulators. Nevertheless, the attitude of consumers toward health-care service advertising has been more positive than negative. The purpose of this study is to create a taxonomy of advertising information features to better describe the relationships between information features in the advertisements and consumer attitudes toward them.

A cross-sectional survey was conducted with 128 health-care consumers in a western state in the USA.

Factor analysis generated seven groups of information features. Among them, information features about access, cost and quality of care were rated as most helpful, whereas providers’ clinical qualifications and communication were rated least helpful. The advertising attitude measure was validated to contain two subscales, one regarding health-care service advertising and the other regarding physicians who advertise. People who highly rated the consumerism features had more positive attitudes toward health-care service advertising and people who highly rated provider clinical qualification features had more negative attitudes toward advertising physicians.

This study made methodological improvements in health-care service advertising research that would be crucial for its theoretical development. It also shed light on consumer characteristics and perceptions about information features that could influence their attitudes toward health-care service advertising.

There is an increasing need for a better understanding of healthcare service marketing in social media. This paper aims to examine Under the framework of positioning theory, popular Instagram posts related to #plasticsurgery and their accounts were analyzed and the relationships between the posts’ attributes and the number of user comments and likes were examined.

A total of 272 posts associated with #plasticsurgery and their account profiles were analyzed.

Plastic surgery procedures were positioned on Instagram primarily by doctors and celebrity patients who were motivated by self-promotion. Doctors often omitted their medical credential information from their account profile and posts while featuring their vanity photos, emojis and consultation solicitations. They showed patients as the objects of surgery. On the other hand, patients positioned themselves as individuals with the agency by showing their faces rather than focusing on their body parts. Instagram users responded better to the doctors who positioned themselves more as business owners than medical professionals by soliciting consultations, offering discounts, displaying surgery photos and using emojis. In responding to patient posts, Instagram users liked under-dressed images more than fully clothed images and commented more on before-and-after photos than others.

In Instagram, doctors positioned themselves as self-interested providers of plastic surgery services, whereas patients positioned themselves as active consumers. Medical professionals’ social media activities should be more closely monitored to protect patient safety and the trust between patients and doctors.

This study shed light on how doctors and patients position themselves on social media and how they are received by social media users in the context of #plasticsurgery on Instagram.

The purpose of this research is to establish an evaluation model for business value of a company's existing patents portfolio to improve the performance of the technology development and the company’s competitiveness through identifying the right direction for technology development.

This research targets 11 leading companies in ten manufacturing industries and one e‐business industry and evaluates their existing patents portfolios. This research developed a core business model set by using clustering and classification. For comparative analysis, this research sets NAVER as a leading company and DAUM as a following company in e‐business industry.

This research proposes nine business model components to evaluate a patent from business perspectives. Second, by evaluating a company's existing patents portfolio in view of business model components, this research proposes the importance of business model components and developed six core business models. Through these role models, companies can analyze the directions for development in the future and find companies with similar characteristics.

This research develops a methodology to provide the direction for technology development of a company by evaluating technologies through the patents portfolio of a company rather than evaluating the value of a single patent. It is different from previous research that evaluates R&D from technology perspectives; this research takes account of the business value of technologies by developing tools in view of business model components.

The purpose of this paper is to examine salient mechanism by which the quality of political and administrative leadership might influence employee engagement in public sector organizations through public service motivation (PSM). Specifically, the purpose of the paper is twofold. First, the psychological outcomes of quality of leadership perceptions among public employees are identified. Second, how PSM mediates the influence of leadership quality perceptions on employee engagement is examined.

This study uses the US Merit System and Protection Board’s (MSPB) 2010 Merit Principles Survey. To establish the distinctive validity of the constructs, the authors performed exploratory factor analysis and confirmatory factor analysis for latent variables, and subsequently conducted validity and reliability analyses. The authors performed a structural equation model to determine relationship between quality of political and administrative leadership, PSM, and employee engagement.

The results reveal that the quality of political and administrative leadership is positively related to PSM and employee engagement. This study also confirmed the mediating role of PSM on the relationship between the quality of political and administrative leadership.

The paper expands the literature through studies that may discover critical mechanisms that are of significance in enhancing employee engagement such as quality of leadership depicted in political and administrative leaders and PSM. While previous studies have extensively explored several antecedents of employee engagement, research focusing on the role of quality in public sector leadership and PSM remains limited.

Previous scholars have assumed that multinational enterprises (MNEs) can reduce the liability of foreignness and increase profitability by investing in corporate social responsibility (CSR). However, empirical validation of this assumption has rarely been attempted. This study aims to provide empirical evidence that the adoption of multi-stakeholder initiatives, which are globally recognized as signals of CSR, helps MNEs increase profits from internationalization.

Fixed effect models, which address model misspecification problems, and instrumental variable estimation, which controls for the endogeneity in firms’ choice of internationalization, offer empirical evidence supporting the moderating effects of global multi-stakeholder initiatives on the relationship between internationalization and firm performance.

This study examines the moderating role of multi-stakeholder initiatives in the relationship between internationalization and firm performance, drawing on signaling and stakeholder theories. The results suggest that the signaling effect of multi-stakeholder initiatives can help MNEs overcome the liability of foreignness and, therefore, profit from overseas markets.

Although the internationalization–firm performance relationship has been a subject of debate in the field of international business, the role of firms’ stakeholder engagement in this relationship has been largely overlooked in previous studies. In this study, the authors explore the impact of multi-stakeholder initiatives on the internationalization–firm performance relationship. Our primary contention is that multi-stakeholder initiatives have moderating effects on this relationship by reducing the liability of foreignness experienced by MNEs in host countries. Furthermore, the findings suggest that active engagement in multi-stakeholder initiatives significantly contributes to the financial success of MNEs as they internationalize.