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Given the ever-growing air travel industry, there is an increasing strain on the systems that provide safe flights. Different methods have to be adopted to help to cope with the increasing demand, especially in Southeast Asia. The purpose of this study is to sectorise one existing airspace to better manage sector workloads.

Cambodia’s airspace was chosen for this study because it had only one sector and it was quickly approaching its limit. In this paper, after characterising the airspace, it was first bi-partitioned using the spectral clustering algorithm. The weights of the resulting subgraphs were then balanced through a weight-balancing algorithm. Also, a post-processing algorithm established the sector boundary to be drawn. The method was first carried out on one test airspace. Following the successful sectorisation of the test airspace, the actual Cambodian airspace was sectorised. The resulting two new sectors were then calculated to be able to last for approximately five years before they would reach their capacity. Hence, a further sectorisation was carried out. This resulted in four sectors, which were projected to last more than 10 years.

The method produced satisfactory results. The methodology presented is proven to be effective in achieving the sectorisation. The workloads of the new sectors obtained are balanced, and the sector boundaries are at least 15 km away from the air routes and nodes. The methodology is also general and can be applied to different scenarios. This means that applications to other airspace in the region are possible, which can further help to increase the safety, efficiency and capacity of the air traffic movement in this region.

This paper presents one of the approaches for airspace sector designs. The problems are clearly presented with references. The authors discuss the advantages and disadvantages of subdividing airspace and the need to sectorise Cambodia’s airspace, and present a method to solve the sectorisation problem. It is very precious to apply methodologies and algorithms to real cases. The presented method offers significant advantages such as the ease of implementation and efficiency. The problems can easily be solved using standard linear algebra algorithms. Instead of looking at the airspace as a whole, and generating new sector boundaries, our algorithm uses current sector boundaries and bisects them. Moreover, only sectors that require sectorisation would be affected. This algorithm has the advantage of maintaining the current sector boundaries to prevent radical changes to daily operations. The Voronoi diagram used in this work does not generate polygonal cells. It instead calculates the area based on pixels. The advantage of doing this is that it offers higher flexibility. Also, the sector boundary is generated based on straight lines calculated by joining the midpoints of links. This is simple and ensures that sections of the sector boundary are made up of straight, distinct lines. The authors also discuss the problems of the method and presented solutions to them.

Airspace sectorization is an important task, which has a significant impact in the everyday work of air control services. Especially in recent years, because of the constant increase in air traffic, existing airspace sectorization techniques have difficulties to tackle the large air traffic volumes, creating imbalanced sectors and uneven workload distribution among sectors. The purpose of this paper is to propose a new approach to find optimal airspace sectorization balancing the traffic controller workload between sectors, subject to airspace requirements.

A constraint programming (CP) model called equitable airspace sectorization problem (EQASP) relies on ordered weighted averaging (OWA) multiagent optimization and the parallel portfolio architecture has been developed, which integrates the equity into an existing CP approach (Trandac et al., 2005). The EQASP was evaluated and compared with the method of Trandac et al. (2005), according to the quality of workload balancing between sectors and the resolution performance. The comparison was achieved using real air traffic low-altitude network data sets of French airspace for five flight information regions for 24 h a day and the Algerian airspace for three various periods (off peak hours, peak hours and 24 h).

It has been demonstrated that the proposed EQASP model, which is based on OWA multicriteria optimization method, significantly improved both the solving performance and the workload equity between sectors, while offering strong theoretical properties of the balancing requirement. Interestingly, when solving hard instances, our parallel sectorization tool can provide, at any time, a workable solution, which satisfies all geometric constraints of sectorization.

This study can be used to design well-balanced air sectors in terms of workload between control units in the strategic phase. To fulfil the airspace users’ constraints, one can refer to this study to assess the capacity of each air sector (especially the overloaded sectors) and then adjust the sector’s shape to respond to the dynamic changes in traffic patterns.

This theoretical and practical approach enables the development and support of the definition of the “Air traffic management (ATM) Concept Target” through improvements in human factors specifically (balancing workload across sectors), which contributes to raising the level of capacity, safety and efficiency (SESAR Vision of ATM 2035).

In their approach, the authors proposed an OWA-based multiagent optimization model, ensuring the search for the best equitable solution, without requiring user-defined balancing constraints, which enforce each sector to have a workload between two user-defined bounds (W_min, W_max).

This paper aims to explore the election cycle and financial markets puzzle in a unique emerging market like Malaysia.

By employing an event-study methodology and wavelet analyses, the author tests for uncertain information hypothesis by examining the reactions of the Kuala Lumpur Composite Index (KLCI) and ringgit surrounding Malaysian general elections, spanning from GE5 (1978) to GE14 (2018). This paper also explores the relationship between KLCI and ringgit.

While the author does not find support for the uncertain information hypothesis, the author uncovers that KLCI tends to overreact following elections, regardless of the winning coalition. The author also records no relationship between KLCI and ringgit in the short run, but the author observes that ringgit leads KLCI in the long run.

The study’s findings bear implications for investors' disposition in the Malaysian equity market. Investors should square off their positions before the general elections to avoid equity market overreactions and potential losses.

Before Malaysia GE14 (2018) general election, Barisan Nasional carried the reputation as one of the longest-serving ruling coalitions in the world since Malaya independence in 1957. However, the ruling coalition was voted out in GE14 (2018), and the Malaysian equity has since dropped.

As investors' expectations shift toward corporate sustainability, many corporations have jumped on the bandwagon of being “green” by issuing green bonds. However, as a recent green financing tool, little attention has been paid on the value that green bonds actually deliver. This causes the problem of greenwashing, in which firms pretend to be environmentally responsible when in reality they are not. This study therefore aims to explore green bonds' impact on issuers' corporate environmental and financial performance.

The sample is collected from among the green bond and conventional bond issues between 2015 and 2019 issued by corporations from various countries. Using the propensity score matching (PSM) and then difference-in-difference (DiD) approaches, two sub-groups (green bond and conventional bond issuers) were generated for comparison. Changes in environmental and financial performance over time between the sub-groups are then examined.

The overall results show that green bonds are effective in improving environmental performance, but only when they are certified by third parties. Additionally, green bonds do not have an impact on financial performance. The findings imply that green bonds' dependency on external certification may be a consequence of an underdeveloped green bond market, where weak governance still dominates the green bond market. Because of this, corporations tend to take advantage of green finance's growing popularity, causing the greenwashing problem.

Green bonds are an extremely new area of research. Few research studies focus on the effectiveness of green bonds in impacting corporate financial and environmental performance. Therefore, this study strives to fill this research gap. It sheds light on the effectiveness of green bonds in supporting the development of green projects and provides a reference point for decision-making in strengthening transparency and accountability in environmental disclosure and helps regulating authorities develop tighter regulatory controls.

The literature has dealt with the relationship between board characteristics (BC) and firm performance (FP) on a large scale. However, it yielded inconsistent results. Thus, this paper aims to examine the indirect relationship between BC and FP through the mediating role of the capital structure (CS).

This study used a sample of 528 non-financial companies listed on Bursa Malaysia from 2015 to 2019. Also, a two-step system generalised method of moments estimation technique was applied.

The results show that board diversity and the frequency of board meetings positively affect financial performance, and it is negatively influenced by board turnover, size and independence. Also, the results indicate a positive relationship between the independence of the board and all CS variables. Importantly, the findings support the policy-setting role of the board of directors where CS (measured by total debt and short-term debt) suppresses some governance mechanisms’ detrimental effect on FP. Hence, the board of directors, apart from the monitoring function, introduce various policies (financial and non-financial) that enhance the overall performance of companies.

These results are consistent with the agency’s perspective that management practices in selecting the optimal capital reduce agency costs and improve performance. The findings contribute to developing a broader theoretical framework that accounts for the policy-setting role of the board of directors. The current study model of corporate governance offers insight for policymakers into the role of corporate governance other than monitoring functions in organisations and how CS should be taken into consideration with corporate governance and FP association.

The operation state of lithium-ion battery for vehicle is unknown and the remaining life is uncertain. In order to improve the performance of battery state prediction, in this paper, a joint estimation method of state of charge (SOC) and state of health (SOH) for lithium-ion batteries based on multi-scale theory is designed.

In this paper, a joint estimation method of SOC and SOH for lithium-ion batteries based on multi-scale theory is designed. The venin equivalent circuit model and fast static calibration method are used to fit the relationship between open-circuit voltage and SOC, and the resistance and capacitance parameters in the model are identified based on exponential fitting method. A battery capacity model for SOH estimation is established. A multi-time scale EKF filtering algorithm is used to estimate the SOC and SOH of lithium-ion batteries.

The SOC and SOH changes in dynamic operation of lithium-ion batteries are accurately predicted so that batteries can be recycled more effectively in the whole vehicle process.

A joint estimation method of SOC and SOH for lithium-ion batteries based on multi-scale theory is accurately predicted and can be recycled more effectively in the whole vehicle process.

The main concern of this research is to examine the indirect effects servant leadership on organisational sustainability (OS) through creativity and psychological resilience in the hoteling sector in Malaysia.

A survey method based on a questionnaire was employed to gather data from 441 employees working in the hotel industry in Malaysia. The partial least squares technique, SmartPLS3.3.7, was employed to examine the hypotheses.

The result of the study found support for effect of servant leadership on creativity and psychological resilience. In addition, the effect of creativity and psychological resilience on OS was supported. Moreover, the mediation role of creativity and psychological resilience between servant leadership and organisational suitability was also supported by data.

This is a pioneering study that has combined human capital elements (i.e. servant leadership, creativity and psychological resilience) to examine their impacts on OS. Besides, this work has established comparatively new relationships, i.e. the impact of servant leadership on OS through the mediating role of creativity and psychological resilience. In addition, this study has developed relatively new link between psychological resilience and OS. In addition, it has confirmed the validity and reliability of servant leadership and OS at first and second orders.

This study aims to provide a comprehensive review of the existing literature on corporate governance (CG) aspects of the Malaysian market. It offers insights into the phases of Malaysian CG, identifies crucial gaps in the literature and outlines an agenda for impending research.

Following a systematic literature review approach, a final sample of 125 studies from Scopus and Web of Science databases was used in this study. These studies were selected based on quality assessment criteria. Then, the sample literature was evaluated in terms of journals, methodology, theories, modelling, research outcomes and CG characteristics.

The results show that there is a growing interest among researchers to further explore CG aspects in Malaysia due to the continuous development of the Malaysian CG codes. Likewise, the review reveals that the majority of prior studies are quantitative and were carried out using archived data from non-financial firms. Also, the existing literature has primarily focused on the outcomes of CG, especially firm performance.

Overall, the results show that there is ample room for future research. The present paper identifies a number of methodological problems and concerns, and discusses the implications of these problems, while also providing recommendations for future research. The main caveat is that the authors use scholarly papers published in academic journals only, but this approach offers them with opportunities for considerable further developments.

To the best of the authors’ knowledge, this study contributes to the literature by being the first of its kind to concentrate on the Malaysian context. It provides a comprehensive knowledge assessment of the Malaysian CG research and offers advice regarding improvements in research, policy and practice by identifying possible knowledge gaps. Consequently, this study provides a cohesive story of the past and a road map for future research on Malaysian CG.

The purpose of this paper is to investigate the effect of stand‐off height (SOH) on the microstructure and mechanical behaviour of the solder joints in high density interconnection.

Cu/Sn/Cu solder joints with 100, 50, 20 and 10 μm SOH are prepared using a reflow process. The microstructures and compositions of solder joints are observed and analyzed by scanning electron microscopy. Tensile testing is carried out to investigate the mechanical properties of the solder joints.

The SOH has a significant effect on the microstructure and mechanical behaviour of Cu/Sn/Cu solder joints. The thickness of the intermetallic compound (IMC) decreases with the reducing SOH; however, their corresponding IMC proportion increases. Meanwhile, the Cu concentration in the solder bulk experiences a marked increase, and the dissolved Cu exists in the forms of a solid solution and Cu‐rich particles at the grain boundary. Because of the higher strain rate and more dissolved Cu in the solder bulk with the reducing SOH, the ultimate tensile strength of solder joints is enhanced. When the SOH reduces to 10 μm, there is only one grain in height in the bulk, and a fracture in the IMC layer occurs. According to the mass balance of substance, a model is established to semi‐quantitatively calculate the consumed Cu thickness, and it is found that the consumed Cu thickness decreases with the reducing SOH.

The paper offers insights into the microstructural and mechanical property changes of the solder joints with the reducing SOH.

The purpose of this article is to establish why the wetting on PCBs with SnCu (HASL) and Snimm finishes in the presence of a flux is better than the wetting of those on a copper substrate. The practical aspect of the obtained results is the main goal of these investigations.

The authors applied the wetting balance method for the wetting measurements at 230 and 250°C, in nitrogen atmosphere, in the presence of the ORM0 type flux. The PCBs with the SnCu (HASL) and Snimm finishes were investigated in the state “as received”. To establish the wetting properties of the SnCu (HASL) and Snimm finishes on the PCBs, wetted by the investigated SnZnBiIn alloys, the SEM and EDX analyses were performed.

The authors obtained very good wetting results of the PCBs with the SnCu and Snimm finishes, wetted by the SnZn7Bi3In4 alloys. By applying the SEM and EDX methods, it was possible to establish that the barrier layer which was created during the HASL process between the copper and the SnCu solder is efficient enough to protect the copper against the influence of the Zn atoms from the SnZn7Bi3In4 solder. This is the reason for an improvement of the wetting properties. An immersion tin finish does not create such barrier layer with the copper. It results in a worse wetting than for the SnCu finishes but a better one than that for the copper. Immersion tin dissolves in the alloys during the soldering and this process delays the reaction between the copper and the Zn atoms from the SnZn7Bi3In4 solder.

It is suggested that further studies are necessary for the confirmation of the practical application, but they should be limited to the reliability of the solder joint performance.

The best wetting results of the PCBs with “tin finishes”, especially with SnCu, wetted by the SnZn7Bi3In4 alloy, at 230 and 250°C and in nitrogen atmosphere, suggest a possibility of a practical usage of the tin‐zinc‐bismuth‐indium alloys for soldering in electronics.

The wetting balance method combined with the SEM and EDX analyses were used as the quickest way to determine the mechanism of the better wettability properties in the case of the PCBs with the SnCu and Snimm finishes, wetted by the SnZn7Bi3In4 alloy, compared to those of the PCBs on the Cu substrate.