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The study investigates whether there is an association between climate types and farm risk attitudes of principal operators.

The study exploits temperature variation in the diverse climate types across the US and defines hot- and cold-climate states. Ordered logit and generalized ordered logit models are used to model principal operators' farm risk attitudes, which are measured on a Likert scale. The study uses two datasets. The first dataset is a 2017 survey of US large commercial producers (LCPs). The second dataset provides a Köppen-Geiger climate classification of the US at a spatial resolution of 5 arcmin for a 25-year period (1986–2010).

The study finds that principal operators in hot-climate states are 4–5% more likely to have a higher willingness to take farm risk compared to principal operators in cold-climate states.

It is likely that farm risk mitigation decisions differ between hot- and cold-climate states. For instance, the authors show that corn acres' enrollment in federal crop insurance and computers' usage for farm business are pursued more intensely in cold-climate states than in hot-climate states. A differentiation of farm risk attitude by hot- and cold-climate states may help agribusiness, the government and economists in their farm product offerings, farm risk management programs and agricultural finance models, respectively.

Based on Köppen-Geiger climate classification, the study introduces hot- and cold-climate concepts to understand the relationship between climate types and principal operators' farm risk attitudes.

This paper investigates thermal mass performance (TMP) in hot climates. The impact of using precast concrete (PC) as a core envelope with different insulation materials has been studied. The aim is to find the effect of building mass with different weights on indoor energy consumption, specifically cooling load in hot climates.

This research adopted a case study and simulation methods to find out the efficiency of different mass performances in hot and humid climate conditions. Different scenarios of light, moderate and heavyweight mass using PC have been developed and simulated. The impact of these scenarios on indoor cooling load has been investigated using the integrated environment solution-virtual environment (IES-VE) software.

The results showed that adopting a moderate weight mass of two PC sheets and a cavity layer in between can reduce indoor air temperature by 1.17 °C; however, this type of mass may increase the cooling demand. On the other hand, it has been proven that adopting a heavyweight mass for building envelopes and increasing the insulation material has a significant impact on reducing the cooling load. Using a PC Sandwich panel and increasing the insulation material layers for external walls and thickness by 50 mm will reduce the cooling load by 15.8%. Therefore, the heavyweight mass is more efficient compared to lightweight and moderate mass in hot, humid climate areas such as the UAE, in spite of the positive indoor TMP that can be provided by the lightweight mass in reducing the indoor air temperature in the summer season.

This research contributes to the thermal mass concept as one of these strategies that have recently been adopted to optimize the thermal performance of buildings and developments. Efficient TMP can have a massive impact on reducing energy consumption. However, less work has investigated TMP in hot and humid climate conditions. Furthermore, the impact of the PC on indoor thermal performance within hot climate areas has not been studied yet. The findings of this study on TMP in the summer season can be generated in all hot climate zones, and investigating the TMP in other seasons can be extended in future studies.

This research will analyze the traditional Iranian buildings according to the climatic factors by the use of graph theory. By this way, the hypothesis that climate factor has a major effect on the organization of the spaces in traditional Iranian buildings will be tested. Access graphs have been used to clarify the connectivity and depth of a building’s spaces from the socio-cultural point of view. However, it cannot be applied to climate studies. Thus, this study developed the existing technique to define building layouts in terms of climate and thermal comfort. The thermal comfort was graphically evaluated by the two main factors like solar gain and wind effect, with the use of a simple multi-attribute rating technique. All the analysis had been done in the interval of zero (the worst condition) to three (the best condition). The proposed orientation-weighted graph method proved that the thermal comfort factors of the buildings under study match the seasonal movements of their inhabitants. Consequently, the developed orientation-weighted graph method can be used to study space organization in traditional Iranian building in terms of solar gain and wind effect.

Window shading has always been an effective technique to control the access of solar radiation; however, inappropriate selection of the shading technique, location and optical properties may lead to an increase in energy consumed for cooling and artificial lighting. Venetian blinds (VBs) are a type of adjustable shading devices that can be installed to the interior, exterior or in between glass panes of a window and that can be easily implemented in both new and existing buildings. This study aims to investigate the impact of three VB parameters: slat angle, reflectivity and location on the overall energy consumption of a residential space with a south-facing facade under the hot arid desert climate of Saudi Arabia’s capital, Riyadh. For the purpose of globalizing the findings, the same investigations were applied for two other cities of similar climates: Cairo, Egypt, and Arizona, the USA.

A test room was modelled for energy simulation, with a 20% window-to-wall ratio. A VB was assigned with alternatives of being located to the indoor, outdoor or in between double glass panes. High, medium and low reflectivity values were applied at each location at slat angle alternatives of 15°, 30°, 45°, 60°, 75° and 90°.

Results showed VB performance across slat angles, where up to 20.1% energy savings were achieved by mid-pane high reflectivity VBs in Riyadh, while the value exceeded 30% in case of being externally located. A similar performance pattern occurred in the other two cities of hot arid desert climates: Cairo and Arizona.

The study is limited to VBs at a fixed position, with no upward movement for partial or full openness conditions. The effect of blind control and operation on performance, such as the amount and duration of openness/closure of the blind and changes in slat angle across time, in addition to VB automation, shall be investigated in a future study.

The better understanding of VB energy performance achieved would enhance a more rational selection of VBs, which would benefit the construction industry as it would assist designers, real estate developer companies, as well as end-users in the decision-making process and help to realize energy-efficient solutions in residential buildings. VB production entities would also benefit by manufacturing and promoting for energy-efficient products.

In this study, a matrix of combinations of three VB parameters was developed, and the effect of these combinations on the overall energy consumption of both artificial lighting and heating, ventilation and air conditioning (HVAC) systems was evaluated and compared to identify the combinations of higher efficiency. The literature showed that these three parameters were hardly investigated in a combined form and hardly assessed by considering the overall energy consumed by both artificial lighting and HVAC.

The stabilization of earthen blocks improves their mechanical strength and avoids adobe construction erosion due to rainwater. However, the stabilization affects the thermal properties of the earthen blocks, and thus their capacity to provide adequate thermal comfort to occupants. This article examines the influence of cement and geopolymer binders on thermal comfort in compressed earthen buildings in hot and arid climates.

The test cell is on the building platform in Burkina Faso. The building is made of compressed earth blocks (CEB) consisting of laterite, water and binder. The thermal models of the building were implemented in EnergyPlus v9.0.1 software. Empirical validation is used to check whether the model used for the thermal dynamic simulation can reproduce with accuracy the thermal behavior in a real situation. The adaptive thermal comfort model of ASHRAE 55–2010 was used to assess thermal comfort in long-term hot and dry tropical conditions.

The results show that the CEB buildings remain hot despite the use of cement or geopolymer binder. Indeed, with both cement and geopolymer binders, on a daily basis, 19 h and 15 h are uncomfortable during, respectively, the hot and cold seasons. An increase of 1% in cement content raises the comfort hours by 9.2 h during the hot season and 11.7 h during the cold season. Hence, the comfort time varies linearly with the cement content in the building material. Moreover, there is no linear relationship between comfort time and geopolymer rate.

Complementary work should also assess the influence of stabilization on building humidity levels. In fact, earthen materials are very sensitive to outdoor humidity and indoor humidity affects thermal comfort even if it is not taken into account in the ASHRAE adaptive thermal comfort model.

The present study will certainly contribute to a better valorization of clay potential in countries with similar climatic conditions.

The use of geopolymer binder is a suitable ecological option to replace the cement binder. It is important to mention that nighttime comfort can be increased through passive strategies such as natural ventilation.

Most CEB material stabilization analyses including cement and geopolymer ones were mostly investigated at the laboratory scale and less at the building scale. Also, the influence of the binder rate on the thermal performance of buildings made of cement and geopolymer has not yet been assessed. This paper fills this gap of knowledge by assessing the impact of cement and geopolymer binder rates on the thermal comfort of CEB dwellings.

The purpose of this paper is to assess the spatial and temporal variations of extreme hot days (H*) and heat wave frequencies across Iran.

The authors used daily maximum temperature (T_max) data of 27 synoptic stations in Iran. These data were standardized using the mean and the standard deviation of each day of the year. An extreme hot day was defined when the Z score of daily maximum temperature of that day was equal or more than a given threshold fixed at 1.7, while a heat wave event was considered to occur when the Z score exceeds the threshold for at least three continuous days. According to these criteria, the annual frequency of extreme hot days and the number of heat waves were determined for all stations.

The trend analysis of H* shows a positive trend during the past two decades in Iran, with the maximum number of H* (110 cases) observed in 2010. A significant trend of the number of heat waves per year was also detected during 1991-2013 in all the stations. Overall, results indicate that Iran has experienced heat waves in recent years more often than its long-term average. There will be more frequent and intense hot days and heat waves across Iran until 2050, due to estimated increase of mean air temperature between 0.5-1.1 and 0.8-1.6 degree centigrade for Rcp2.6 and Rcp8.8 scenarios, respectively.

The trend analysis of hot days and heat wave frequencies is a particularly original aspect of this paper. It is very important for policy- and decision-makers especially in agriculture and health sectors of Iran to make some adaptation strategies for future frequent and intense hot days over Iran.

Several calls have been everywhere asking for proper use of passive design tools like shading devices, insulation, natural ventilation and solar panels in building architecture of hot-dry area in order to improve the thermal performance of indoor spaces. This paper examines the effect of these passive tools on indoor thermal performance which in turn helps arrange thermal priorities properly. Herein, basic principles of Successive Integration Method (SIM) have been utilized for an integrated design of two floors with small openings integrated with floor cooling, solar panels, natural ventilation, shading devices, and insulation. As a result, create priorities of passive tools that are structured consequently for ventilation, insulation, solar panels, and shading devices. This structure could guide designers and builders to set their priorities for the new development of building construction.

This paper aims to address Passive Design Strategies (PDSs) in the traditional houses of Sabzevar and to assess the adaptation level of these strategies to the climate of the region.

Identifying the Sabzevar climate, five samples of traditional houses have been chosen to be analyzed via two stages. In stage one, the efficiency of each strategy is weighted through qualitative analysis, and in stage two, the houses are simulated in EnergyPlus 9.3.0 to quantitatively evaluate their heating and cooling performances.

The obtained results from the energy performance analysis of the case studies indicate that the houses present diverse energy performances in different seasons. Those buildings with PDSs for both cold-arid and hot-arid climates, however, are more adaptable cases to the climate of the region.

The results of this study are expected to provide a basis of materials and methods for the climatic assessment of the traditional buildings, specifically traditional houses and will open new doors to future studies about the integration of these potential PDSs with the new technological developments and climate considerations as well as protecting the conservation policies of these buildings by means of optimizing and improving their energy performance and implementing effective retrofit scenarios.

The contemporary urban fabrics in hot climate regions have overextended urban spaces that face problems of high heat stress due to intense solar radiation and air temperature and that cause the pedestrians to abandon the urban spaces due to thermal discomfort. This work introduced the shading effects as one of the prime factors that contribute to restore thermal comfort and attract pedestrian activities. The purpose of this paper is to identify the proportional limits of the urban space to maintain feasible shades for pedestrian activities.

The urban space abstracted into a floor surrounded by four walls was then classified into four typologies. The assessment tool was developed to calculate the shading efficiency at the floor level of urban space. The width and the length of the floor equally was expanded in the range (0.5/0.5 to 4.0/4.0). The average shading efficiency of the expanded typologies was calculated along three intervals (Morning, midday and afternoon). The results were then analyzed, and critical guidelines were established that could be utilized in the design of the futuristic urban space and provide amendments to the existing urban space.

The paper concluded that the performance of urban spaces was not due to the accumulative performances of all walls but rather due to the combination specific effective walls in response to the interactive variations shading patterns concerning daily pedestrian activities. Any large shallow urban space could be segmented into multiples of the recommended typologies by a vertical landscape.

It is the first study that identified the expansion limit of the urban space that maintains feasible shades for the pedestrian. A further value of this study is establishing guidelines to the urban designers for the effective configurations of the urban space in terms of shading. These guidelines could be utilized in the design of the futuristic urban space and provide amendments to the existing urban space.

Despite worldwide climate change and the problems caused by using fossil fuels, energy consumption in the world keeps rising every year. The areas with extremely cold or scorching climates are large, and significant amounts of energy are getting used in these areas for heating, cooling, and ventilation. The general purpose of this study is to investigate the possible relationship between the climatic characteristics of the Esfahak, a village located in the hot desert region of Iran, and the physical characteristics of its built environment.

The method of this research is qualitative and somewhat descriptive-analytical. In this regard, the architectural features of Esfahak village are compared with the principles mentioned in the Mahoney tables to determine the degree of compliance of the architecture of this village with the climatic condition.

The results show that design principles have been used in all indicators discussed in the Mahoney tables. By applying these principles, not only did the acute weather conditions not prevent the initial settlement in the village location, they have not caused inhabitants to leave the site over time as well.

The impacts of bioclimatic design strategies on thermal comfort in hot desert regions are seldom studied. This research provides evidence-based and informed design recommendations that can help building designers and city authorities integrate bioclimatic design strategies at the earliest conceptual design phases in hot desert climates.