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The main purpose of the study is to examine the influence of family directors on the firm performance of public listed companies (PLCs) in Malaysia. This study provides empirical evidence on the agency problems between controlling shareholders and minority interests in the concentrated ownership setting.

Samples of the study are 112 PLCs in year 2006. Two measures of firm performance are used: return on assets (ROA) and Tobin’s Q. Managerial ownership refers to the percentage shareholdings of executive directors with direct and indirect holdings. It was further categorized into family ownership and non-family ownership.

In relation to ROA, managerial ownership is found positively significant. The results also show that the positive relationship between managerial ownership is contributed by the managerial-non-family ownership. In relation to Tobin’s Q, the results show a U-shape with turning point at 31.38% for managerial ownership and 28.29% for the managerial-family ownership. The results found significant and positive relationships between managerial ownership and both measures of firm performance which indicates that managerial ownership and family ownership yield greater efficiency.

The study highlights the effects of corporate governance on ROA and Tobin’s Q are somewhat different. It provides some evidence on the need to use appropriate measure of firm performance. The significant relationship supports the argument of Chami (1999), Fama and Jensen (1983), and DeAngelo and DeAngelo (1985) and empirical evidence of Lee (2004) that family ownership enhances monitoring activities.

Differentiating the types of managerial ownership into family and non-family categories enriches our knowledge about who actually contributes to the improved performance.

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.

The time development of the symmetrical standing zones of recirculation, which is formed in the early stages of the impulsively started laminar flow over the square cylinder, have been studied numerically. The Reynolds number considered ranges from 25 to 1,000. Main flow characteristics of the developing recirculation region aft of the square cylinder and its interaction with the separating shear layer from the leading edges are studied through the developing streamlines. Other flow characteristics are analysed in terms of pressure contours, surface pressure coefficient, wake length and drag coefficient. Four main‐flow types and three subflow types of regimes are identified through a detailed analysis of the evolution of the flow characteristics. Typically, for a given Reynolds number, it is noted that flow starts with no separation (type I main‐flow). As time advances, symmetrical standing zone of recirculation develops aft of the square cylinder (type II main‐flow). The rate of growth in width, length and structure of the aft end eddies (sub‐flow (a)) depends on the Reynolds number. In time, separated flow from the leading edges of the square cylinder also develops (type III main‐flow) and forms growing separation bubbles (sub‐flow (b)) on the upper and lower surfaces of the square cylinder. As time advances, the separation bubbles on the upper and lower surfaces of the cylinder grow towards downstream regions and eventually merge with the swelling symmetrical eddies aft of the cylinder. This merging of the type II and type III flows created a complex type IV main‐flow regime with a disturbed tertiary flow zone (sub‐flow (c)) near the merging junction. Eventually, depending on the Reynolds number, the flow develops into a particular category of symmetrical standing recirculatory flow of specific characteristics.

The growth of social media and the sharing economy is generating abundant unstructured image and video data. Computer vision techniques can derive rich insights from unstructured data and can inform recommendations for increasing profits and consumer utility – if only the model outputs are interpretable enough to earn the trust of consumers and buy-in from companies. To build a foundation for understanding the importance of model interpretation in image analytics, the first section of this article reviews the existing work along three dimensions: the data type (image data vs. video data), model structure (feature-level vs. pixel-level), and primary application (to increase company profits vs. to maximize consumer utility). The second section discusses how the “black box” of pixel-level models leads to legal and ethical problems, but interpretability can be improved with eXplainable Artificial Intelligence (XAI) methods. We classify and review XAI methods based on transparency, the scope of interpretability (global vs. local), and model specificity (model-specific vs. model-agnostic); in marketing research, transparent, local, and model-agnostic methods are most common. The third section proposes three promising future research directions related to model interpretability: the economic value of augmented reality in 3D product tracking and visualization, field experiments to compare human judgments with the outputs of machine vision systems, and XAI methods to test strategies for mitigating algorithmic bias.

The purpose of this paper is to present a quick inspection method based on the post-flight data to examine static aeroelastic behavior for transport aircraft subjected to instantaneous high g-loads.

In the present study, the numerical approach of static aeroelasticity and two verified cases will be presented. The non-linear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling of artificial intelligence techniques based on post-flight data. The first and second derivatives of flight dynamic and static aeroelastic behaviors, respectively, are then estimated by using these aerodynamic models.

The flight dynamic and static aeroelastic behaviors with instantaneous high g-load for the two transports will be analyzed and make a comparison study. The circumstance of turbulence encounter of the new twin-jet is much serious than that of four-jet transport aircraft, but the characteristic of stability and controllability for the new twin-jet is better than those of the four-jet transport aircraft; the new twin-jet transport is also shown to have very small aeroelastic effects. The static aeroelastic behaviors for the two different types can be assessed by using this method.

As the present study uses the flight data stored in a quick access recorder, an intrusive structural inspection of the post-flight can be avoided. A tentative conclusion is to prove that this method can be adapted to examine the static aeroelastic effects for transport aircraft of different weights, different sizes and different service years in tracking static aeroelastic behavior of existing different types of aircraft. In future research, one can consider to have more issues of other types of aircraft with high composite structure weight.

This method can be used to assist airlines to monitor the variations of flight dynamic and static aeroelastic behaviors as a complementary tool for management to improve aviation safety, operation and operational efficiency.

The purpose of this paper is to present the irregular deviation examination of flight control surfaces and the potential problem diagnosis of irregular deviations for the jet transport aircraft. A four-jet transport aircraft at transonic flight in cruise phase is the study case of the present article.

The standard lift-to-drag ratio (L/D) and flight dynamic models are established through flight data mining and the fuzzy logic modeling technique based on the flight data of quick access recorder available in the Flight Operations Quality Assurance (FOQA) program of the airlines. The irregular deviations of flight control surfaces are examined by the standard L/D model-predicted results through sensitivity analysis. The contribution values in L/D deficiency are predicted by the deviations and the L/D derivatives of all influencing variables in Taylor series expansion. The potential problems due to irregular deviations can be excavated by the flight dynamic models through the analysis of in-flight stability and controllability.

The magnitude of stabilizer angle to the deficiency of L/D is the largest among the four control surfaces and elevator is the second one through the judgment of contribution values in L/D deficiency. The stabilizer has irregular deviations with obvious endplay problems of jackscrew, as found in the present study. The stabilizer is suggested to have the unscheduled maintenance for the flight control rigging.

The specific transport aircraft of the standard L/D model should be the best one in L/D performance among all transport aircraft in the fleet of the airlines. The present method is a new concept to monitor the irregular deviation of flight control surface. The study case of the four-jet transport aircraft at transonic flight in cruise phase is illustrated as the standard L/D mode. The required flight data of monitored flight is requested to eliminate the biases through compatibility checks. The flight data of study case in the present study is also illustrated as monitored flight data.

To diagnose the irregular deviations of flight control surface deflected angles with contributing to the L/D deficiency estimation is an innovation to improve the flight data analysis of FOQA program for airlines. If the irregular deviation problems of control surfaces can be fixed after rigging in maintenance, the goal of flight safety and aviation fuel saving will be achieved.

The flight control surface rigging of unscheduled maintenance is not expected to coincide with an airline’s peak season or unavailable space in hangar. The optimal time of unscheduled maintenance for the flight control rigging will be easily decided through the correlations between excessive fuel cost and flight safety.

This method can be used to assist airlines to monitor irregular angular positions of flight control surfaces as a complementary tool for management to improve aviation safety, operation and operational efficiency.

The onset of climate change is expected to result in variations in weather patterns which can exacerbate water scarcity issues. This can potentially impact the economic productivity of nations as economic activities are highly dependent on water especially for agricultural countries. In response to this, the concepts of virtual water and water footprint have been introduced as metrics for measuring the water intensity of products, services and nations. Researchers have thus looked into virtual water trade flows as a potential strategy for alleviating water scarcity. The paper aims to discuss these issues.

Environmentally extended input-output models (IOMs) are often used to analyze interactions between economic and ecological systems. This work thus develops a multi-regional input-output model for optimizing virtual water trade between different geographic regions in consideration of local environmental resource constraints, product demands and economic productivity.

A case study on agriculture crop production and trade in different regions of the Philippines is utilized to demonstrate the capabilities of the model. The results show that the optimal strategy does not necessarily limit a water-scarce region to produce less water-intensive crops.

The model uses an input-output framework whose fixed coefficients reflect a fixed technological state. As such, the model is best used for short-term projections, or projections for mature technological state (i.e. where no major gains in efficiency or yield can be foreseen).

The proposed modeling framework can be used in any geographic region (provided relevant statistical data are available for calibration) to provide decision support for optimal use of limited water resources.

The model proposed in this work has general applicability to the optimal planning of agro-industrial systems under water footprint constraints. This modeling approach will be particularly valuable in the future, as climate change causes changes in precipitation patterns and water availability.

Recent development of wireless communication devices dictates that miniaturization, multi-functions and high integration are the important factors for antenna structures. This has resulted in the requirement of antennas with dual or multi-frequency operations. Although the dual-band antennas can be achieved through the experience-based configuration selection with the parameter adjustment, it is still a challenging problem to design an antenna with specific dual-frequency operations effectively. The purpose of the paper is to develop an effective design method to guide the design of antennas with specific dual-frequency operations.

The topology optimization is carried out through the material distribution approach, where the patch of the antenna is taken as the design domain. The optimization formulation is established with maximizing the minimum antenna efficiency at the target frequencies. The sensitivity of the antenna efficiency with the design variables is derived, and the optimization problem is solved by a gradient-based algorithm.

Based on the proposed design method, an example of a patch antenna design for specific dual-frequency operations is presented. The performance of the designed antenna is cross-verified by experimentation, where the reflection coefficients (S₁₁) obtained by simulation and experiment show a good agreement. The simulation and the experimentation of the designed antenna show that two operational bands are optimized to occur around the target frequencies, which confirms the effectiveness of the proposed design method.

This paper presents a topology optimization-based design method for patch antennas operating at dual specific frequencies.

The Women in Leadership Development (WLD) Initiative is a year-long, multifaceted co-curricular leadership development opportunity created to support the unique developmental needs of emerging women leaders. WLD was intentionally designed around the context of second-generation gender bias with a firm grounding of research and theory on gender and leadership.

Organized around three leadership pathways – leadership training, leadership coaching, and leadership support networks – WLD brings together the best practices of leadership development in combination with feminist pedagogy and critical perspectives to foster meaningful and impactful development of women leaders.

This paper describes the design of the initiative and how each leadership pathway supports the leadership development journey for emerging women leaders. It provides a model that is impactful as well as foundational, for undergraduate women’s leadership development.

Women leaders, in particular, can benefit from leadership development that takes gender into account (DeFrank-Cole & Tan, 2022a; Ely et al., 2011).