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1 – 10 of over 4000The purpose of this paper is to examine the Summer performance, comfort, and heat stress in structural timber buildings. The research utilises building simulation as a tool to…
Abstract
Purpose
The purpose of this paper is to examine the Summer performance, comfort, and heat stress in structural timber buildings. The research utilises building simulation as a tool to investigate the performance of the case study buildings under non-extreme weather conditions.
Design/methodology/approach
The research explores three UK sites using the test reference year (TRY) weather files for the current and future weather conditions. The study focuses on the Summer performance and heat stress in non-extreme weather conditions; therefore, the Design Summer Year (DSY) weather files are not used for the simulations. The simulation data are calibrated and validated using the measured data from the field study.
Findings
The results revealed the mean predicted temperatures varied from 20.2–20.8°C for the 2000s. The mean temperatures for the 2030s ranged from 23.1 to 24.2°C. Higher temperatures are predicted at the buildings in the Southeast site than the Midlands and the Northwest sites. The results revealed that there is no significant improvement in the thermal environment when the floor area and the floor-to-ceiling height are increased. However, the study showed that the integration of different design interventions can improve the future performance and resilience of the buildings in various weather conditions.
Research limitations/implications
By applying the wet-bulb globe temperature (WBGT) and the Universal Thermal Comfort Index (UTCI) mathematical models to calculate the heat stress at the buildings, the study proposes the WBGT of 20.0°C and the UTCI of 24.1°C as possible heat stress indicators for occupants of the buildings in the 2030s.
Practical implications
On the one hand, the results revealed the maximum temperatures in some of the case study buildings exceed the comfort threshold (28°C). On the other hand, the study showed that occupants of the buildings are not prone to extreme Summertime overheating and heat stress under moderate weather conditions. However, different outcomes may be predicted if DSY weather files for the selected sites are considered.
Originality/value
This study is the first reported work to explore building simulation and mathematical equations to investigate Summer performance, comfort and heat stress indexes in timber buildings under moderate weather conditions in different regional sites in the UK.
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Mahzabin Chowdhury, Khan Salam and Richard Tay
The purpose of this paper is to understand consumer preferences for green vehicles with low fuel consumption and emission. It will examine six important vehicle attributes…
Abstract
Purpose
The purpose of this paper is to understand consumer preferences for green vehicles with low fuel consumption and emission. It will examine six important vehicle attributes, including fuel efficiency and CO2 emissions, and determine the impacts of increasing demand for green attributes on the domestic car industry in Sweden.
Design/methodology/approach
Responses to an adaptive choice-based conjoint experiment from a sample of 100 residents in Northern Sweden were analyzed using monotone regression and market simulation.
Findings
The authors found that consumer preferences were sensitive to changes in fuel efficiency and emission levels. However, engine power was the most important attribute for existing owners whereas price was the most important one for potential customers, while both market segments valued emission more than fuel efficiency. Also, the domestic producer will benefit from both an increase in market size and market share if all new vehicles have higher fuel efficiency but its market share will decrease if all new vehicles have lower CO2 emissions.
Social implications
Although promoting green vehicle purchase is beneficial for the environment, policy makers also need to balance this benefit against any potential adverse effect on the domestic industry and the economy. This study will provide evidence-based recommendations to increase the share of green cars in new vehicle purchase, and thus contribute to improving the environment. Moreover, it will also predict the changes in the market shares of different vehicles, and the potential impact on the domestic automobile manufacturing sector and the economy.
Originality/value
This study will contribute significantly to the understanding of consumer preferences by exploring the preferences of a sample of consumers from a country with a well-established alternative fuel and green car market but has adverse weather and driving conditions and a domestic automobile manufacturing industry. It will also examine the differences in preference between existing owners and potential green car buyers. Finally, it will simulate the effects of changing fuel efficiency and emission levels on consumer utility and preference shares to predict changes in market share of different vehicles, and thus the potential impact on the domestic automobile manufacturing sector and the economy.
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TOUFIC M. MEZHER and WISSAM TAWIL
The present paper presents the major causes of delays in the construction industry in Lebanon and the relative importance of these postponements. A survey of a randomly selected…
Abstract
The present paper presents the major causes of delays in the construction industry in Lebanon and the relative importance of these postponements. A survey of a randomly selected sample of 11 owners, 15 contractors and 10 architectural/engineering (A/E) firms from Lebanon was undertaken. The survey included 64 causes of delay, grouped into 10 major groups, in which the participants were asked to indicate their level of importance of each delay. The level of importance of the causes and the groups were measured and ranked by the importance index for owners, contractors and A/E firms. It was found that all three parties generally agreed on the ranking of the major categories of delay factors. Owners had more concerns with regard to financial issues, while contractors ranked contractual relationships highest, and finally, A/E firms ranked project management highest.
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Alexandros M. Goulielmos, Markos A. Goulielmos and Androniki Gatzoli
The purpose of this paper is to inform readers comprehensively and sufficiently about the marine accident of MV Samina Express with 80+2 dead in the Aegean Sea in September 2000.
Abstract
Purpose
The purpose of this paper is to inform readers comprehensively and sufficiently about the marine accident of MV Samina Express with 80+2 dead in the Aegean Sea in September 2000.
Design/methodology/approach
The paper uses analysis of court and experts as well as published papers on the accident using nonlinear management techniques.
Findings
When dialogue and communications in shipping companies fail then accidents to vessels result.
Research limitations/implications
There was difficult access to court material and limited information on actual causes and the action of payers.
Practical implications
Open communications can aid in finding the cause of accidents.
Originality/value
The paper reveals the causes of accident due to human errors in a clear way; it outlines the responsibility of the captain as manager of the ship; and shows where and why the dialogue and communication fails.
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Aitor Erkoreka, Ivan Flores-Abascal, Cesar Escudero, Koldo Martin, Jose Antonio Millan and Jose Maria Sala
Understanding the dynamic hygrothermal behavior of building elements is very important to ensure the optimal performance of buildings. The Laboratory for Quality Control in…
Abstract
Purpose
Understanding the dynamic hygrothermal behavior of building elements is very important to ensure the optimal performance of buildings. The Laboratory for Quality Control in Buildings of the Basque Government tested a flat roof designed by a construction company that developed a building to be constructed using prefabricated modules. This is a five to eight floor building with ventilated façade and a flat roof covered by gravel with the possibility of changing it to a green cover. The paper aims to discuss this issue.
Design/methodology/approach
The interest of this research was threefold. The first objective was to accurately test, under real dynamic weather conditions, the roof design in a PASLINK test cell to obtain the U-value and the thermal capacitance of the different roof layers, and of the roof as a whole, through the precise calibration of resistance-capacitance mathematical models of the roof. Based on the parameters and experimental information of these calibrated models, a second goal was to calibrate and validate a Wufi model of the roof.
Findings
This second calibrated model was then used to simulate the dynamic hygrothermal behavior of the roof, obtaining the roof’s hourly thermal demand per square meter for a whole year in different locations considered in the Spanish Building Code. These simulations also permitted the authors to study the risk of condensation and mold growth of the tested component under different climatic conditions.
Originality/value
The successful combination of the PASLINK method to calibrate the Wufi hygrothermal model is the main novelty of this research.
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The purpose of this paper is to examine the seasonal performance, occupants’ comfort and cold stress in cross-laminated timber school buildings located in the USA (Northeast…
Abstract
Purpose
The purpose of this paper is to examine the seasonal performance, occupants’ comfort and cold stress in cross-laminated timber school buildings located in the USA (Northeast region).
Design/methodology/approach
The Fall survey was done from October–November 2017. In the Winter, it was considered from December 2017–February 2018. The study measured environmental parameters in the chosen spaces. The research applied the wet-bulb globe temperature (WBGT) model to determine the indexes in various seasons.
Findings
In the Fall, the average inside temperature was 21.2°C, the average RH was 50.7 per cent, and the mean dew-point was 9.3°C. The mean inside temperature was 20.5°C in the Winter while the mean RH was 23.9 per cent and the average dew-point was −1.9°C. The overall mean inside temperatures in both seasons were within the ASHRAE comfort temperature limits for cold seasons. During the surveys, higher average values of temperature, RH and dew-point were measured in the offices than the other spaces.
Practical implications
The research showed people might be subject to lower temperatures in the hall than the other spaces. Some design parameters and occupation hours may contribute to the lower temperatures reported in the hall than the different spaces.
Originality/value
The study proposes the WBGT of 16.0°C and 13.7°C as the stress indexes in the Fall and Winter seasons correspondingly. Last, the research suggests a WBGT of 14.9°C as the overall mean stress index within the spaces considered in this study.
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The purpose of this paper is to present the advantages of a solar store system with transpired solar air collector (TSC) in North Wales, UK. The collectors are designed as a…
Abstract
Purpose
The purpose of this paper is to present the advantages of a solar store system with transpired solar air collector (TSC) in North Wales, UK. The collectors are designed as a proposal to meet the target of the solar air storage and heating project to improve the efficiency of solar collectors in the UK.
Design/methodology/approach
IES software simulation is used to examine the potential of a solar store system in Deeside Leisure Centre compared to the traditional constant air volume (CAV) system and CAV system with heat pump. The design parameters and configurations are determined on the basis of the monitoring results gained from recent experiments.
Findings
The result demonstrates good agreement between simulations and monitoring results and the solar store system demonstrates considerably lower energy consumption compared to the traditional CAV system with and without heat pump.
Originality/value
The usage of TSC is proven to be useful in improving COP of the heat pumps and reducing overall energy consumption in a leisure center. The framework proposed in this study could also be applied to different building types in order to highlight their advantages.
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Introduction Concrete is a mixture of naturally occurring geological aggregates bonded together by a cementitious agent which ‘sets’ by reacting with water. This setting process…
Abstract
Introduction Concrete is a mixture of naturally occurring geological aggregates bonded together by a cementitious agent which ‘sets’ by reacting with water. This setting process is called ‘hydration’ and is not a dissolution process. The advantages of concrete are as follows:
Prospects for Sub-Saharan African economies in 2018.