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This paper considers locating congested fast charging stations (FCSs) and deploying chargers in a stochastic environment, while the related studies have predominantly focused on problems in deterministic environments. Reducing the inconvenience caused by congestion at FCSs is an important challenge for FCS service provider. This is the underlying motivation for this study to consider a problem for FCS network design with the congestion restriction in a stochastic environment. We proposed a maximal coverage problem subject to budget constraints and a congestion restriction in order to maximize the demand coverage. With the derivation of the congestion restriction in the considered stochastic environment, the problem is formulated into an integer programming model. A real-life case study is conducted and managerial implications are drawn from its results.

Autism spectrum disorder (ASD) is a lifelong disorder that requires intervention and support services for a growing geriatric population. The purpose of this paper is to examine the mean age at death of individuals with ASD and subsequent comorbidity with Alzheimer’s disease, and any form of dementia, as a whole and according to sex.

Data consisted of 1,754 individuals who had an ASD listed as one of the causes of deaths from the National Vital Statistics System with data from 1999 to 2015. In the current study, the authors present contradictory results with a mean age at death for individuals with ASD was 68 years by adjusting for changing prevalence rates.

Females with ASD had a higher mean age at death than males with ASD; consistent with the trend in the sex differences in the general population. The results of the current study also indicate that individuals with ASD were, in fact, less likely than the general population to have Alzheimer’s disease or a form of dementia. However, males with ASD were significantly more likely to have acquired Alzheimer’s disease or a form of dementia as compared to females with ASD.

Guan and Li (2017) reported a mean age at death of 36 years old for individuals with ASD, which was subsequently reported in the mass media, most notably CNN. The authors contend that this study provides a more accurate estimate mean age at death.

The research aims to establish importance scheme of geospatial factors for land valuation activities that may serve as an eye-opener and aid the concerned government agencies in drafting land valuation policies and guidelines to achieve a sound land governance and administration. It specifically identifies and weighs geospatial valuation factors to establish their importance.

The research involves discussions and survey questionnaires given to land experts (i.e. appraisers, environmental planners, land economist, geodetic engineers and assessors) who indicated their opinions on influence of geospatial factors on land value. The analytic hierarchy process (AHP) is then used to weigh the factors in terms of its importance.

The result was then compared with the multiple regression analysis (MRA) taking into consideration the standardized regression coefficient of the 15 factors. The AHP method found out the major road accessibility and slope direction as the most and least influential factors, respectively, while surprisingly MRA found major road accessibility not significant at p < 0.05 level of significance.

The research generally reflects the sub-urban type of study area; hence, inclusion of other road types such as express ways and subways and performing sensitivity analysis of AHP are suggested in future studies.

The findings of the study will provide information of concerned government agencies in improving valuation activities, as well as to update values regularly based on the geospatial factors.

To the best of the authors’ knowledge, this study is the first effort to rank geospatial factors with analytic hierarchy analytic process that further considered both their negative and positive influences on land value. The approach surmounts the flaw and shortcomings of empirical methods of identifying importance of factors.

Meta-heuristic algorithms are efficient in achieving the optimal solution for engineering problems. Hybridization of different algorithms may enhance the quality of the solutions and improve the efficiency of the algorithms. The purpose of this paper is to propose a novel, robust hybrid meta-heuristic optimization approach by adding differential evolution (DE) mutation operator to the accelerated particle swarm optimization (APSO) algorithm to solve numerical optimization problems.

The improvement includes the addition of DE mutation operator to the APSO updating equations so as to speed up convergence.

A new optimization method is proposed by introducing DE-type mutation into APSO, and the hybrid algorithm is called differential evolution accelerated particle swarm optimization (DPSO). The difference between DPSO and APSO is that the mutation operator is employed to fine-tune the newly generated solution for each particle, rather than random walks used in APSO.

A novel hybrid method is proposed and used to optimize 51 functions. It is compared with other methods to show its effectiveness. The effect of the DPSO parameters on convergence and performance is also studied and analyzed by detailed parameter sensitivity studies.

IN order to obtain a clear view of the analysis it is perhaps better first to consider the analogy of a channel section rigidly attached to two cylinders subjected to a shear at their in the plane of the web of the channel (see Fig. 1).

Accurate perception of the environment using range sensors such as laser scanner, SONAR, infrared, vision, etc., for the application, such as path planning, localization, autonomous navigation, simultaneously localization and mapping, is a highly challenging area. The reliability of the perception by range sensors relies on the sensor accuracy, precision, sensor model, sensor registration, resolution, etc. Laser scanner is even though accurate and precise but still the efficient and consistent mapping of the environment is yet to be attained because laser scanner gives error as the extrinsic and intrinsic parameters varied which cause specular reflection, refraction, absorption, etc., of the laser beam. The paper aims to discuss this issue.

This paper presents an error analysis in sensory information of laser scanner due to the effect of varying the scanning angle with respect to the optical axis and surface reflectivity or refractive index of the targets. Uncertainties caused by these parameters are reduced by proposing a new technique, tilt mounting system (TMS) with designed filters of tilting the angular position of a laser scanner with the best possible selection of range and scanning angle for the robust occupancy grid mapping. Various experiments are performed in different indoor environments, and the results are validated after the implementation of the TMS approach with designed filters.

After the implementation of the proposed TMS approach with filters, the errors in the laser grid map are reduced by 15.6 percent, which results in 62.5 percent reduction in the collision of a mobile robot during autonomous navigation in the laser grid map.

The TMS approach with designed filter reduces the effect of variation in intrinsic and extrinsic parameters to generate efficient laser occupancy grid map to achieve collision-free autonomous navigation.

This study aims to evaluate the performance of the Portuguese fund managers by examining the selectivity and market timing skills of 51 Portuguese mutual funds from June 2002 to March 2012.

The authors assess empirically the performance of a sample of funds by applying the unconditional and conditional models of Treynor and Mazuy (1966) and Henriksson and Merton (1981).

The results suggest that, overall, the Portuguese mutual funds do not possess selectivity or timing skills. However, regardless of the model used, the domestic equity funds exhibit a statistically significant market timing ability. Furthermore, the domestic and North American equity funds display positive selectivity during bull markets and timing skills during bear markets. Additionally, there is some evidence that older funds are better stock pickers than younger funds.

To address some of the limitations of this study, the authors suggest for further research correcting the Treynor and Mazuy (1966) model for the convexity cost of replicating Merton’s (1981) option approach. Additionally, for further research, we suggest using a bigger sample, higher frequency data, as such data may lead to higher frequency of timing ability as proposed by Bollen and Busse (2001). To overcome some of the limitations of traditional models, future research may consider using Jiang’s (2003) nonparametric test, as it is not affected by manager’s risk aversion, or Ferson and Khang (2002) conditional performance evaluation using portfolios holdings.

The authors contribute to the current literature by extending the period of study to 10 years in comparison to previous studies; extending the sample of funds to 51; addressing, for the first time in this context, the importance of public information on funds’ performance, through the comparison of unconditional and conditional models of Treynor and Mazuy’s (1966) and Henriksson and Merton’s (1981); and, for the first time in the Portuguese context, analysing the relationship between funds’ size, age and market cycles and selectivity and market timing skills.

This paper aims to discuss factors affecting temporary migrants' ability to access and make effective use of public and private healthcare services in the Republic of Cyprus (hereafter referred to as Cyprus). These factors are raised in the context of a larger study focusing on the healthcare needs of temporary migrants from non‐EU countries living and working in Cyprus.

Semi‐structured interviews with 13 domestic workers and 17 students from Sri Lanka, Pakistan, Bangladesh, India and the Philippines explored migrants' experiences with accessing and utilizing healthcare services in Cyprus. The theoretical framework utilized is grounded in the health capability approach which focuses on individuals' confidence and ability to be effective in achieving optimal health.

The study highlights issues concerning the accessibility and acceptability of healthcare services which emerge as the result of both the organisation and delivery of healthcare services and social, political and economic structures.

The implications of this study are relevant in the current debate taking place at the EU level about the opportunities and challenges of temporary migration. Specifically, it is argued that governments and societies should promote individual freedoms and opportunities that empower people to lead the lives they want to live.

Temporary migrants form a group whose experiences and needs have not been as extensively investigated as those of other migrant groups, particularly in Cyprus. The capability approach allows for assessing both policy and health systems taking into consideration equity and the impact of multi‐sectoral influences on health.

The study aims to reveal the state of building operation and maintenance (O&M) manpower in Hong Kong. In addition, the study included supply and demand of O&M practitioners, gaps between their required and possessed competences and ways to meet the manpower needs.

After developing a model that integrates manpower levels (L), trades (T) and natures (N) of O&M works (named as “LTN” model), a full spectrum of O&M jobs were established followed by collecting data of 75 organizations and 402 stakeholders through two surveys.

Besides the large O&M workforce, vacancy rates of the jobs were found to be significant. For the different trades and natures of O&M works, the knowledge/skills levels perceived by the stakeholders were lower than the corresponding importance levels.

The methodology of the study can be used in future research for revealing the state of O&M manpower in Hong Kong and cities alike. The way in which the “LTN” model was developed may be used as a reference for constructing similar models for manpower research in other industries.

The findings and the measures for improving the O&M manpower can assist policymakers and human resources departments to formulate necessary education and training courses for the building industry.

The study is the first of its kind focusing on building O&M manpower. The state of the manpower it unveiled forms a basis for comparison with similar findings in future.

The purpose of this paper is to analyze the network structure of technology in and between different fields, as well as the evolution of their relations.

Using the patent data in Derwent Innovation Index (DII) from 1991 to 2010, this paper analyzes the co-classification of Derwent Manual Code (DMC) of patents in all technology fields. Large-scaled co-classification matrices are employed to generate the DMC co-classification networks. In addition, analyses are pursued at different levels of aggregation in four five-year windows: 1991-1995, 1996-2000, 2001-2005 and 2006-2010. Using Girvan-Newman algorithm in the clustering process, the structure transformations over time are detected.

The paper identifies the key technological knowledge in certain fields and finds out how different technological fields are connected and integrated. What is more, the dynamic evolution between networks in different time periods reveals the trend of generic technology development in the macroscopic level.

The paper investigates a large quantity of data – all the patent data in DII from 1991 to 2010 in this paper. The paper applies Girvan-Newman algorithm in the co-classification analysis and uses co-classification networks to reveal technology network structures. Evolution coincident with the realistic technological shifts can be observed.