Search results

1 – 10 of over 23000
To view the access options for this content please click here
Article

Md. Jewel Rana, Md. Rakibul Hasan and Md. Habibur Rahman Sobuz

Application of appropriate shading device strategies in buildings can reduce direct solar heat gain through windows as well as optimize cooling and artificial lighting…

Abstract

Purpose

Application of appropriate shading device strategies in buildings can reduce direct solar heat gain through windows as well as optimize cooling and artificial lighting load. This study investigates the impact of common shading devices such as overhangs, fins, horizontal blinds, vertical blinds and drapes on energy consumption of an office building and suggests energy efficient shading device strategies in the contexts of unique Bangladeshi subtropical monsoon climate.

Design/methodology/approach

This research was performed through the energy simulation perspective of a prototype office building using a validated building energy simulation tool eQUEST. Around 100 simulation patterns were created considering various types of shading devices and building orientations. The simulation results were analysed comprehensively to find out energy-efficient shading device strategies.

Findings

Optimum overhang and fin height is equal to half of the window height in the context of the subtropical climate of Bangladesh. South and West are the most vulnerable orientations, and application of shading devices on these two orientations shows the highest reduction of cooling load and the lowest increment of lighting load. An existing building was able to save approximately 7.05% annual energy consumption by applying the shading device strategies that were suggested by this study.

Originality/value

The shading device strategies of this study can be incorporated into the Bangladesh National Building Code (BNBC) as new energy-efficient building design strategies because the BNBC does not have any codes or regulations regarding energy-efficient shading device. It can also be used as energy-efficient shading device strategies to other Southeast Asian countries with similar climatic contexts of Bangladesh.

Details

Smart and Sustainable Built Environment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-6099

Keywords

To view the access options for this content please click here
Article

Abhijeet M. Malge and Prashant Maruti Pawar

Three different configurations of vertical axis wind turbines (VAWT) were fabricated by changing the storey height and their orientations. The purpose of this study is to…

Abstract

Purpose

Three different configurations of vertical axis wind turbines (VAWT) were fabricated by changing the storey height and their orientations. The purpose of this study is to find the effect of storey height and orientation on the performance of wind turbines. The multistory VAWT has three storeys. The first configuration had increased middle storey height, with 0–90-0 orientation of blades. Wherein the second turbine had equal storey heights. The third configuration had increased middle storey height with 0–120-240 orientation of blades. The blades were tested numerically and experimentally.

Design/methodology/approach

In this research work, prototypes of innovative multistory VAWT were built with different configurations and orientations. Three configurations of three-storey VAWT were fabricated by varying the height of storey of turbines. The orientations were made by keeping the storeys orthogonal to each other. Multistory VAWT was tested numerically and experimentally. ANSYS Fluent was used for computational fluid dynamic analysis of VAWT. K-epsilon model was used for numerical analysis of wind turbine. Experimentation was carried out in a wind tunnel for different tip speed ratios (TSR).

Findings

The three configurations of innovative multistory VAWT were tested numerically and experimentally for different TSR. It has been found that the VAWT with equal storey height had a better performance as compared to the other two configurations with increased middle storey height. The power coefficient of equal storey height VAWT was about 22%, wherein the power coefficient of turbines with reduced upper and lower storey height was between 5%–8%

Research limitations/implications

The research work of multi-storey VAWT is very novel and original. The findings of the research will contribute to the existing work done in the field of VAWT. This will help other researchers to have insight into the development of multistory VAWT. The effect of storey height and configuration of multi-storey VAWT is studied numerically and experimentally, which concludes that the performance of equal storey is superior as compared to other configurations.

Practical implications

The multi-storey concept of VAWT was developed to counter the problem of wind direction. The blades of each storey were arranged orthogonal to each other. This helped to harness wind power irrespective of the direction of the wind. This will make the VAWT more sustainable and financially viable for domestic use.

Social implications

The turbines are specially designed for remotely located housed in rural areas where the power grid is not yet reached. Users can install the turbine on their rooftop and harness wind power of 100 W capacity. This will help them to make their life easy.

Originality/value

This research work is very original and first of a kind. The multistory concept of the wind turbine was checked for the effect of storey height and orientations of blades on its performance. Different configurations and orientations of the vertical axis were designed and developed for the first time.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

Keywords

To view the access options for this content please click here
Book part

Eric B. Schneider

This paper is the first to use the individual level, longitudinal catch-up growth of boys and girls in a historical population to measure their relative deprivation. The…

Abstract

This paper is the first to use the individual level, longitudinal catch-up growth of boys and girls in a historical population to measure their relative deprivation. The data is drawn from two government schools, the Marcella Street Home (MSH) in Boston, MA (1889–1898), and the Ashford School of the West London School District (1908–1917). The paper provides an extensive discussion of the two schools including the characteristics of the children, their representativeness, selection bias and the conditions in each school. It also provides a methodological introduction to measuring children’s longitudinal catch-up growth. After analysing the catch-up growth of boys and girls in the schools, it finds that there were no substantial differences between the catch-up growth by gender. Thus, these data suggest that there were not major health disparities between boys and girls in late-nineteenth-century America and early-twentieth-century Britain.

Details

Research in Economic History
Type: Book
ISBN: 978-1-78635-276-7

Keywords

To view the access options for this content please click here
Book part

John Komlos and Leonard Carlson

We analyze heights of Indian scouts in the U.S. army born between ca. 1825 and 1875. Their average height of ca. 170 cm (67 in.) confirms that natives were tall compared…

Abstract

We analyze heights of Indian scouts in the U.S. army born between ca. 1825 and 1875. Their average height of ca. 170 cm (67 in.) confirms that natives were tall compared to Europeans but were nearly the shortest among the rural populations in the New World. The trend in their height describes a slightly inverted “U” shape with an increase between those born 1820–1834 and 1835–1839 of ca. 1.8 cm (0.7 in.) (p = 0.000) and a subsequent slight decline after the Civil War. This implies that they were able to maintain and perhaps even improve their nutritional status through the Civil War, though harder times followed for those born thereafter. We also recalculate the heights of Native Americans in the Boas sample and find that the Plains Indians were shorter than most rural Americans. The trend in the height of Indians in the Boas sample is similar to that of the scouts.

Details

Research in Economic History
Type: Book
ISBN: 978-1-78350-487-9

Keywords

To view the access options for this content please click here
Book part

Leslie Rott

This chapter examines the everyday experiences of short women, focusing on the problems they face and the coping strategies used to navigate being short in a heightist…

Abstract

Purpose

This chapter examines the everyday experiences of short women, focusing on the problems they face and the coping strategies used to navigate being short in a heightist society. Further, this chapter views height as a stigmatized identity, which both negatively and positively impacts short women.

Methodology

Sixteen qualitative interviews were conducted with women 5′2″ and under.

Findings

Using the literature on stress, and coping models laid out by social psychologists, this chapter elucidates the unique place of short women in American society.

Originality

While there has been a wealth of literature on how short stature impacts men, research on how short stature impacts women has been scant.

Details

Disability and Intersecting Statuses
Type: Book
ISBN: 978-1-78350-157-1

Keywords

To view the access options for this content please click here
Book part

Rebecca Sear, Nadine Allal and Ruth Mace

We examine the relationship between height and reproductive success (RS) in women from a natural fertility population in the Gambia. We observe the predicted trade-off…

Abstract

We examine the relationship between height and reproductive success (RS) in women from a natural fertility population in the Gambia. We observe the predicted trade-off between adult height and age at first birth: women who are tall in adulthood have later first births than short women do. However, tall women have reproductive advantages during the rest of their reproductive careers, primarily in the lower mortality rates of their children. This ultimately leads to higher fitness for taller women, despite their delayed start to reproduction. The higher RS of tall women appears to be entirely due to the physiological benefits of being tall. There is no evidence that female height is related to patterns of marriage or divorce in this population.

Details

Socioeconomic Aspects of Human Behavioral Ecology
Type: Book
ISBN: 978-1-84950-255-9

To view the access options for this content please click here
Book part

Gregori Galofré-Vilà, Andrew Hinde and Aravinda Meera Guntupalli

This chapter uses a dataset of heights calculated from the femurs of skeletal remains to explore the development of stature in England across the last two millennia. We…

Abstract

This chapter uses a dataset of heights calculated from the femurs of skeletal remains to explore the development of stature in England across the last two millennia. We find that heights increased during the Roman period and then steadily fell during the “Dark Ages” in the early medieval period. At the turn of the first millennium, heights grew rapidly, but after 1200 they started to decline coinciding with the agricultural depression, the Great Famine, and the Black Death. Then they recovered to reach a plateau which they maintained for almost 300 years, before falling on the eve of industrialization. The data show that average heights in England in the early nineteenth century were comparable to those in Roman times, and that average heights reported between 1400 and 1700 were similar to those of the twentieth century. This chapter also discusses the association of heights across time with some potential determinants and correlates (real wages, inequality, food supply, climate change, and expectation of life), showing that in the long run heights change with these variables, and that in certain periods, notably the thirteenth and fourteenth centuries, the associations are observable over the shorter run as well. We also examine potential biases surrounding the use of skeletal remains.

Details

Research in Economic History
Type: Book
ISBN: 978-1-78756-582-1

Keywords

To view the access options for this content please click here
Book part

Howard Bodenhorn, Timothy W. Guinnane and Thomas A. Mroz

Long-run changes in living standards occupy an important place in development and growth economics, as well as in economic history. An extensive literature uses heights to…

Abstract

Long-run changes in living standards occupy an important place in development and growth economics, as well as in economic history. An extensive literature uses heights to study historical living standards. Most historical heights data, however, come from selected subpopulations such as volunteer soldiers, raising concerns about the role of selection bias in these results. Variations in sample mean heights can reflect selection rather than changes in population heights. A Roy-style model of the decision to join the military formalizes the selection problem. Simulations show that even modest differential rewards to the civilian sector produce a military heights sample that is significantly shorter than the cohort from which it is drawn. Monte Carlos show that diagnostics based on departure from the normal distribution have little power to detect selection. To detect height-related selection, we develop a simple, robust diagnostic based on differential selection by age at recruitment. A companion paper (H. Bodenhorn, T. Guinnane, and T. Mroz, 2017) uses this diagnostic to show that the selection problems affect important results in the historical heights literature.

To view the access options for this content please click here
Article

Zhiyuan Li, Lijuan Zheng, Chengyong Wang, Xin Huang and Jiechi Xie

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic…

Abstract

Purpose

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic product and the popularity of wearable devices. The reliability of circuit could be influenced by the hole quality of FPC, such as burrs, which is one of the major problem in FPC.

Design/methodology/approach

In this paper, micro-drill with a diameter of 0.1 mm was used to drill the double-sided flexible copper clad laminate. The thrust force, the burr and tool wear were investigated. The influencing factors of the height of the burrs were studied. The relationship between the thrust force and the height of the burrs was also explored. Finally, the formation mechanism of burrs was analyzed.

Findings

The entrance burrs were usually less than the exit burrs. The burr height increased with the feed per rotation. The height of the burr increased with the increase of the thrust force for the plastic deformation of the copper foil was dominant. The abrasion of the drill gave rise to increase the height of burr. In micro-hole drilling, the growth of burrs can be suppressed effectively by reducing the clearance between the FPC and the backup plate. The thrust force would be controlled in a certain range to reduce the burr with specific drilling parameters. There existed a certain relationship of Gaussian distribution between the height of the burrs and the thrust force of FPC.

Originality/value

The reliability of the integrated circuit was directly affected by the burrs of the FPC. This research on the formation mechanism of FPC burrs and forecast of burr height provided a firm foundation for further work in the area of improvement of the micro-hole quality.

Details

Circuit World, vol. 46 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

To view the access options for this content please click here
Article

Jianzhong Shang, Xin Li, Zhuo Wang, Rong Wang and Hong Zhu

This study aims to investigate rheological and extrusion behavior of thermosetting epoxy resins, which to find the universal property and printing parameters for…

Abstract

Purpose

This study aims to investigate rheological and extrusion behavior of thermosetting epoxy resins, which to find the universal property and printing parameters for extrusion-based rapid prototyping applications.

Design/methodology/approach

The thickener proportion greatly influences its viscosity and rheological behavior and therefore plays an important role in the shape of the cross-section of the extrudate.

Findings

A pseudoplastic (shear-thinning) is a basic requirement for obtaining extruded lines with plump cross-sections. In addition to the effects of the rheological behavior of the composite, shape maintenance and its wettability on the substrate, the cross-sectional geometry of the extrudate is also strongly affected by printing process parameters including the extrusion nozzle height, nozzle moving speed, extrusion rate and critical nozzle height. Proper combinations of these process parameters are necessary to obtain single-line extrudates with plump cross-sections and 3-D objects with dimensional accuracy, uniform wall thickness, good wall uprightness and no wall slumping. Formulas and procedures for determining these extrusion parameters are proposed and demonstrated in experiments.

Originality/value

The results obtained have been explained in terms of the interactions among the rheological properties of the composite, the shear rate imposed on the composite during extrusion, the wettability of the composite on the substrate and the shape maintenance of the composite during extrusion.

Details

Rapid Prototyping Journal, vol. 25 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

1 – 10 of over 23000