Tight bounds for NF-based bounded-space online bin packing algorithms

In Zheng et al. (J Comb Optim 30(2):360–369, 2015) modelled a surgery problem by the one-dimensional bin packing, and developed a semi-online algorithm to give an efficient feasible solution. In their algorithm they used a buffer to temporarily store items, having a possibility to lookahead in the list. Because of the considered practical problem they investigated the 2-parametric case, when the size of the items is at most 1 / 2. Using an NF-based online algorithm the authors proved an ACR of \(13/9 = 1.44\ldots \) for any given buffer size not less than 1. They also gave a lower bound of \(4/3=1.33\ldots \) for the bounded-space algorithms that use NF-based rules. Later, in Zhang et al. (J Comb Optim 33(2):530–542, 2017) an algorithm was given with an ACR of 1.4243,  and the authors improved the lower bound to 1.4230. In this paper we present a tight lower bound of \(h_\infty (r)\) for the r-parametric problem when the buffer capacity is 3. Since \(h_\infty (2) = 1.42312\ldots \), our result—as a special case—gives a tight bound for the algorithm-class given in 2017. To prove that the lower bound is tight, we present an NF-based online algorithm that considers the r-parametric problem, and uses a buffer with capacity of 3. We prove that this algorithm has an ACR that is equal to the lower bounds for arbitrary r.     

The Standard of Living of the Workers in a Spanish Industrial Town: Wages,Nutrition, Life Expentancy and Heigth in Alcoy (1870–1930)

This is the first study that empirically examines how migration influences migrants’ time use patterns in China, utilizing a mixed-method approach. We systematically estimate the migration effects on weekly hours on working, leisure, personal care and domestic responsibilities, based on data from the nationally representative 2010 Chinese Family Panel Studies. We then supplement these analyses with in-depth interviews conducted in Beijing to further understand the underlying mechanisms. Compared with urban locals, rural-to-urban migrants have longer work hours and less leisure time. The largest differences are found among men. On average, migrant men work 5 h longer and have 7 fewer hours of leisure per week than urban local men. These differences are moderated by migrants’ and their parents’ socioeconomic status, and their family responsibilities. The in-depth interviews reveal that the busier work schedules are largely motivated by the transient nature of most rural-to-urban migration and the overwhelming economic pressures for household establishment and career development.     

Shaping LGBTQ Identities: Western Media Representations and LGBTQ People’s Perceptions in Rural Spain

A growing academic discussion has focused on how, in a globalized world, LGBTQ identities are shaped and influenced by different and international actors, such as the media. This article analyzes how LGBTQ people from a rural region of a Western country—Spain—feel toward their representations on TV series from English-speaking countries. Employing a qualitative approach, this research aims to depict whether the academic conceptualizations to analyze these identity conformation processes are accurate. In addition, it explores how dominating media representations are being adapted in a region that, although within the West, can serve a context of a very different nature. The results found that a major rejection of the TV series representations among participants can suggest both an inaccuracy of the conceptualizations used by some scholars to understand LGBTQ flows and a problematic LGBTQ representation in media products that goes beyond regions and spaces.     

Private condominiums in Luanda: more than just the safety of walls,a new way of living

ABSTRACT

Since its independence in 1975, Angola’s capital Luanda has been going through deep processes of demographic, economic, social and physical transformations. In this article, apart from introducing the case study of private condominiums in the general discussion on urban studies in the Global South, we focus on the dynamics of transformations regarding housing for the mid/upper strata, providing the background for the emergence and recent expansion of gated communities/condominiums, a phenomenon that has acquired major importance in the recent decades in Luanda. The specialised literature relates the demand for and multiplication of these residential structures in Africa with issues such as the search for safety associated with demonstrations of exclusive lifestyles. In the case of Luanda, the authors found––through a case study and qualitative data collected among residents and non-residents of condominiums––that, contrary to the results from other studies, condominiums in Luanda are essentially sought after primarily for functional reasons such as access to infrastructure and better living.     

Dehumanization and Islamophobia: attitudes towards the Syrian refugee crisis / Deshumanización e islamofobia: actitudes ante la crisis de los refugiados sirios

The dehumanization of certain outgroups is manifested in the deligitimization of the other and generates exclusion, especially in conditions perceived as potentially threatening. The purpose of this study is to analyse the perceptions of Syrian refugees and image of the Muslim population among young people between the ages of 15 and 18 (n = 205) and people over the age of 60 (n = 117). To do so, scales of dehumanization, modern racism and Islamophobia were applied and analysed according to certain variables such as age and degree of perceived religiosity. The results show that there are significant differences in terms of age in dehumanization, modern racism and Islamophobia, but the dehumanization of both Muslims and Syrian refugees seems to appear at all levels, with the perception of threat as a crucial factor. Religiosity also seems to be a significant variable in the study of racism and Islamophobia, although not in dehumanization. The psychosocial implications of these findings are discussed.     

Physical workload during firefighting in Chilean volunteers

The study was performed in a sample of 39 firemen. The state of health for each fire fighter was evaluated by means of a clinical examination and also through some specific exams. Aerobic capacity was estimated as an indicator of physical fitness. In each load, cardiac frequency and oxygen consumption were measured under a steady state condition. Additionally, body composition was calculated using a Tanita professional scale. Physical effort at work was determined by measuring cardiac frequency using a telemetric unit. Evaluations were carried out during night shifts, registering information under the following conditions: night shifts without emergency, fire simulation, training exercises and real fire fighting. In general terms, it is possible to state that fire fighters are healthy according to the result of the clinical examination. However, it is very important to highlight that 70% of the firemen consume alcohol and 80% were smokers. The average aerobic capacity of the sample was 2.6 l/min or 34.5 ml/kg/min. In terms of overweight and obesity, the body mass index was 25.7, whereas the percentage fat mass reached an average of 22.9 %. The cardiovascular load in the night shifts without emergencies did not surpass 40%, which in Chile is considered the highest limit for sustained work. However, during training, simulations and real fires, the firemen had higher cardiac frequencies, reaching peak levels close to 100% cardiovascular load.     

The inclusion of ergonomic tools in the informational, conceptual and preliminary phases of the product design methodology

The process of product development has received special attention as it is being recognized as a source of competitive gain. Through its systematic use companies reduce costs, increase quality and decrease development time. However, one can find products being launched on the market that cause dissatisfaction to its users, and in consequence if the customer feels harmed or injured he will no longer purchase a product from the same brand. This in regard only to the commercial aspect; usually the danger of an accident or injury is not even thought about. This paper is the basis of the dissertation master's degree and used a literature research to build the repertoire, analyzing the methodologies applied by product design engineers, designers and ergonomists. The analysis results demonstrate the inefficiency of the design methodologies ergonomic issues. The contribution of this work lies in the suggestion to include ergonomic tools in all phases of product development and the presentation of a table with the tools that points out its most suitable time of application and results.     

Analysis of mental workload of electrical power plant operators of control and operation centers

Electrical systems can be categorized as critical systems where failure can result in significant financial loss, injury or threats to human life. The operators of the electric power control centers perform an activity in a specialized environment and have to carry it out by mobilizing knowledge and reasoning to which they have adequate training under the terms of the existing rules. To reach this there is a common mental request of personnel involved in these centers due the need to maintain attention, memory and reasoning request. In this sense, this study aims to evaluate the Mental Workload of technical workers of the Control Centers of Electrical Energy. It was undertaken a research on operators control centers of the electricity sector in Northeast Brazil. It was used for systematic observations, followed by interview and application of the instrument National Aeronautics and Space Administration Task Load Index known as NASA-TLX. As a result there will be subsidies for an assessment of mental workload of operators, and a contribution to improving the processes of managing the operation of electric utilities and the quality of workers.