Economy of RHA （Rice Husk Ash） in Concrete for Low-Cost Housing Delivery in Nigeria

Delivery of housing units in adequate quantity and quality has been the pursuits of individuals and successive governments in Nigeria. Still, the gap between demand and supply is becoming wider on daily basis due to exorbitant cost of building materials that is beyond the reach of average Nigerians. Concrete being the most acceptable construction material is expensive due to high cost of cement. Efforts made to reduce the cost of cement were to no avail, thus there is need to look elsewhere. Past researches showed that substituting cement with 15% of RHA （rice husk ash） in concrete improves the performance of concrete and reduces global warming as a result of emissions from cement production. This paper looks into the effect of using RHA as partial substitute of cement on the cost of a low-cost housing unit. Results showed that cement based construction materials are responsible for 82.58% of the total cost in which cement is responsible for 42%. When 15% RHA was used to substitute cement over N90,000 was saved, amounting to about 7% of the total cost of the building. In addition, depletion of natural resources was reduced.

AN INTEGRATED DESIGN PROCESS OF LOW-COST HOUSING IN CHILE

This paper discusses the application of Integrated Design Process for the design of low-cost housing in Chile.It aims to question common practice for the development of housing based on prescriptive regulations and non-interdisciplinary work,which has resulted in poor quality building requirements.The first stage consisted in defining performance requirements for aspects such as energy demand,U value,air tightness and indoor air quality for a specific case of low-cost houses located in the city of Temuco.An integrated design process was carried out by an interdisciplinary team of professionals specialized in each of the performance aspects that were taken into account.The construction and post-occupancy stages were characterized by verifying the performance requirements,which resulted in a low-cost house prototype that included strategies for energy efficiency and a healthy indoor environment.

Metropolitan Housing Development in Urban Fringe Areas-A Case Study of Three Metropolitan Cities of South Africa: Johannesburg, Ekurhuleni and Tshwane

Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of South Africa and has a strong presence and contributes in areas of manufacturing sector,financial and business services,retail and wholesale trade,etc.The rapid urban population,increase in the informal settlements and socio-economic opportunities has resulted in considerable urban sprawl in and around the urban fringe areas of these metropolitan cities.The urban fringe areas of these metros often come under the influence of rapid urbanization process and pressures.Coupled with the economical and potential land dynamics and lack of priority of spatial development guidelines,these areas attract rapid and haphazard development from communities and developers.Research Design/Methodology:This research is based on a qualitative approach through a comprehensive literature review that included content analysis of key documents on housing sector such as IDPs(Integrated Development Plans),Municipal Annual Reports,Growth Development Strategies,and among other sectoral documents on housing sector.Some of the key priority issues considered in the housing sector included:eradication of housing backlogs,spatial restructuring of housing,provision of choice in terms of location,tenure and housing typology.Findings:The current paper discusses the approaches of metropolitan housing development processes in three metropolitan cities of South Africa from Gauteng region,namely:Johannesburg,Ekurhuleni and Tshwane.The paper discusses the existing housing sectoral scenario along with the fringe areas in three cities with focus on:formal and informal settlements,housing segregation and the backlogs,current institutional arrangements,role of public private participation,and scope for alternate mechanisms.The paper concludes in discussion on sustainable development options for housing development in urban fringe areas.

Microstructure and properties of 35 kg large aluminum alloy flywheel housing components formed by squeeze casting with local pressure compensation

The squeeze casting method with local pressure compensation was proposed to form a flywheel housing component with a weight of 35 kg.The numerical simulation,microstructure observation and phase characterization were performed,and the influence of local pressure compensation on feeding of thick-wall position,microstructure and mechanical properties of the formed components were discussed.Results show that the molten metal keeps a good fluidity and the filling is complete during the filling process.Although the solidification at thick-wall positions of the mounting ports is slow,the local pressure compensation effectively realizes the local forced feeding,significantly eliminating the shrinkage cavity defects.In the microstructure of AlSi9Mg alloy,α-Al primarily consists of fragmented dendrites and rosette grains,while eutectic Si predominantly comprises needles and short rods.The impact of local pressure compensation on strength is relatively minimal,yet its influence on elongation is considerable.Following local pressure compensation,the average elongation at the compensated areas is 9.18%,which represents a 44.90%higher than that before compensation.The average tensile strength is 209.1 MPa,and the average yield strength is 100.6 MPa.The local pressure compensation can significantly reduce or even eliminate the internal defects in the 35 kg large-weight components formed by squeeze casting.

Emergency Housing Solutions after Earthquakes:Innovative Technologies and Resilience Strategies

The international research project,developed through the collaboration between the University of Chieti and Pescara“G.d'Annunzio”and theÉcole Nationale d'Architecture of Marrakech,aims to explore new strategies for emergency housing,with a focus on technological innovation and the resilience of temporary shelters.The main goal of the research is to define a more efficient housing module for post-earthquake scenarios,based on the analysis of the most advanced international solutions for first-response shelters.This study has made it possible to identify both the strengths and weaknesses of existing proposals,leading to the development of a housing model capable of improving living conditions during emergency phases.The objective is to propose an innovative housing module that not only addresses immediate post-disaster needs but is also adaptable to the specific socio-cultural characteristics of the affected populations.As a result of this work,the“DIVA-Variable Dimension Emergency Shelter”project was developed.This housing model stands out for its ability to adapt to the needs of different emergency phases,offering a versatile and customizable solution that effectively addresses post-earthquake challenges while ensuring respect for cultural specificities and improving quality of life.

Industrialization,Efficiency and Social Housing:Sustainable Prefabrication for the Colombian Social and Cultural Context

This research aims to generate processes of industrialization and qualification of social housing in Colombia through prefabrication,low energy consumption and high environmental quality to reduce the current deficit and improve the quality of life in communities with fewer economic resources.Modular coordination and the use of materials with thermal behaviors,appropriate to the country’s climatic characteristics,reduce production costs,avoid waste and improve the architectural and environmental quality of social housing.Passive cooling strategies,such as controlling solar incursion and generating natural cross ventilation eliminate energy consumption and allow reaching desired standards of comfort.In a context in which traditional construction systems have still not resolved the social housing deficit in Colombia and which generate high costs for energy consumption in the search for thermal comfort,industrialized and efficient construction with high environmental quality provides solutions according to the economic,geographic,social and cultural context in Colombia.

Assessing and Optimizing the Technical Life of Architectural Components of Low-Cost Multistoried Rental Housing in Jakarta

Low-cost multistoried rental housing （rumah susun sederhana sewa, abbreviated to rusunawa） recently has become the main policy for the Indonesian government to provide adequate housing for low income people in the metropolitan areas. In line with the policy, the government in the year 2005 has raised the technical life of building for low-cost multistoried rental housing from 30 years to 50 years. This study is conducted to assess variables that affect the technical life of architectural components, using Delphi study method involving stakeholders who have participated in the planning, design, construction, operation and maintenance of low-cost multistoried rental housing in Jakarta. Research findings contribute significantly to the assurance of technical life of architectural components in low-cost multistoried rental housing in Indonesia.

Living in a Condominium Regime:Neighborhood Conflicts in Low-Income Housing,Tijuana,Baja California-A Secondary Publication

This paper analyzes neighborhood conflicts arising from the condominium property regime,under which social housing promoted by Mexican government institutions and private developers is acquired.This regime has facilitated access to housing for the salaried population,but it is far from contributing to the attainment of the right to housing.The research takes as case studies housing complexes located in the city of Tijuana,Baja California,Mexico.The analysis included a mixed methodology.Firstly,similar case studies were analyzed;secondly,a review of the Condominium Property Regime Law was carried out in order to understand its implications.In view of the pandemic situation,a virtual survey was applied to the inhabitants of these areas,as well as interviews with presidents of neighborhood committees of these complexes.From the above,it was found that this form of ownership generates conflicts,reflected in the dissatisfaction of the inhabitants with their housing,disagreements and controversies in their organization and coexistence.The inhabitants have to collectively solve the problems they face,related to the maintenance and use of common areas,insecurity,and cleanliness,among others.In addition,there is a lack of support from local authorities.With this,it is concluded that although the inhabitants have a space that solves their housing problem,it does not manage to be a space that adequately guarantees their right to housing.

A Triple Nexus Water-Energy-Housing (WEH) Framework Modelling towards Improved Decision-Making in Humanitarian Operations

Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute unsustainability to inadequate provision of basic resources and highlight the apparent bottlenecks that prevent access to the meaningful data needed to plan and remedy problems. Most operations have relied on an “ad hoc ism” approach, employing parallel and disconnected data processing methods, resulting in a wide range of data being collected without subsequent prioritization to optimize interconnections that could enhance performance. There have been little efforts to study the trade-offs potentially at stake. This work proposes a new framework enabling all subsystems to operate in a single system and focusing on data processing perspective. To achieve this, this paper proposes a Triple Nexus Framework as an attempt to integrate water, energy, and housing sector data derived from a specific sub-system within the overall system in the application of Model-Based Systems Engineering. Understanding the synergies between water, energy, and housing, Systems Engineering characterizes the triple nexus framework and identifies opportunities for improved decision-making in processing operational data from these sectors. Two scenarios illustrate how an integrated platform could be a gateway to access meaningful operational data in the system and a starting point for modeling integrated human settlement systems. Upon execution, the model is tested for nexus megadata processing, and the optimization simulation yielded 67% satisfactory results, demonstrating that an integrated system could improve sustainability, and that capacity building in service delivery is more than beneficial.

手机Housing检包线平衡分析及优化设计

针对某电子企业手机Housing检包线目前存在的生产效率低下、劳动成本上升的问题,依据作业测定技术所获得的数据,结合Flexsim仿真技术分析检包线瓶颈,运用方法研究分别从作业方式和工站布置两个方面,对检包线进行平衡分析和优化设计,并通过Flexsim建立优化后的检包线仿真模型验证其有效性,采用新方案后,在成本降低的情况下,达到了平衡各工站负荷、提高生产效率的目的。研究表明,工业工程理论方法与仿真技术相结合,可使制造系统的改善更加有效。

Field survey of indoor thermal comfort in rural housing of northern China in heating season

This paper introduces a field measurement of an indoor thermal environment in rural housing in suburban Beijing from December 2008 to March 2009.The indoor environment parameters such as air temperature,mean radiant temperature（MRT）,airflow velocity and relative humidity are measured.A questionnaire survey of the occupants＇ thermal sensations in these surveyed houses is conducted and their daily activities and clothing conditions are recorded.The results show that the thermal neutral temperature of rural housing is 18.4 ℃,and the lower limit of acceptable temperature range can be extended to 10.9 ℃.The comfortable indoor temperature is affected by the occupants＇ clothing and lifestyle.Therefore,the indoor temperature standards of space heating for suburban housing cannot be simply duplicated from that for urban housing.Compared with occupants in suburban Beijing,it is found that the occupants in rural Hunan province feel colder at the same operative temperature due to the high relative humidity in Hunan province.

Simulation of urban affordable housing land-use evolution based on CA-MAS model

In order to simulate the evolution of affordable housing land use a dynamic model that combines cellular automata CA and a multi-agent system MAS is established.This paper aims to utilize the approach of decision factors on site selection of affordable housing through a literature review to construct a hierarchy model of those factors identifying the weight of each factor by an analytic hierarchy process AHP .Based on those weight factors the CA-MAS model is designed. Nanjing city is taken as an example to verify the feasibility of the model.The results show that the CA-MAS model is pragmatic and effective in simulating evolution of affordable housing land use which also promotes the fundamental understanding and perception of the development of affordable housing and urbanization.

国外“合作居住”(Co-Housing)社区开发过程解析

"合作居住"社区是20世纪60年代最早出现在丹麦的一种新型居住模式。总体上说,其开发过程可以归纳为开始阶段、编制发展计划阶段、编制设计及施工文件阶段以及建造阶段。文章将介绍"合作居住"社区开发的开发模式、主要流程、居民参与过程、建筑师的职能和开发过程中通常使用的一些关键性策略,对这些开发经验加以分析和整理,希望对中国房地产开发提供一些参考。

Design Drivers for Affordable and Sustainable Housing in Developing Countries

Current demand for housing worldwide has reached unprecedented levels due to factors such as human population growth, natural disasters and conflict. This is felt no more so than in developing countries which have experienced disproportionate levels of demand due to their innate vulnerability. Many current approaches to housing delivery in developing countries continue to utilize inappropriate construction methods and implementation procedures that are often problematic and unsustainable. As such affordability and sustainability are now vital considerations in the international development debate for housing the poor in developing countries in order to meet the long term sustainable development goals and needs of housing inhabitants. This paper utilized an extensive scoping study to examine the various facets impacting on design decision making relative to sustainable and affordable housing delivery in developing country contexts. Aspects of affordability, sustainability, design decision making, appropriate technology use, cultural awareness, as well as current barriers to affordable and sustainable construction in developing countries are examined in detail. Results highlighted the capability of indigenous knowledge, skills and materials as well as selected appropriate technology transfer and cultural awareness by foreign bodies can be utilized in innovative ways in addressing current housing needs in many developing country contexts.

Evaluation of Large-Scale Housing Projects in Terms of Their Compatibility to Criteria of Environmental Design

The design and execution of large-scale housing projects always have negative environmental impacts in terms of excessive consumption of non-renewable energy resources and environmental pollution. These negative impacts are multiplied in the case of large-scale housing projects where a large number of standardized units are implemented in a repeated manner. This proposed paper will study and evaluate the environmental impacts of large-scale housing projects according to criteria of environmental design. The case study project is Haram City that is a housing project for small low-income families. The project consists of 50,000 housing units and is located in 6th of October City, which has a hot dry desert climate that necessitates special design considerations and applications of environmental design concepts. The project will be analyzed and evaluated in terms of site layout, design of buildings, orientation, materials used, construction techniques, thermal behavior, landscaping, etc.

Relationship between Housing Price and Land Price Based on Grey Relational Analysis

In recent Years, China＇s real estate market has been rapid developed, and real estate has become a hot spot of consumption and investment. In some large and medium-sized cities there has been a rapid rise in housing prices. The rapid rise in housing prices has led to difficulties in the purchase of houses in some cities and towns, and this phenomenon has aroused the attention and con- cern of all walks of life. Housing is the basic human life needs. Housing problem is not only an economic problem, but also a social problem. The relationship between house price and land price and the effective control of housing prices have become the focus of government and scholars. Thus, grey relational analysis is used to ana- lyze the relationship between housing prices and land prices, and the grey relational coefficients are calculated.

CHINA'S URBAN HOUSING SYSTEM IN TRANSITION

This paper discusses transition of urban housing system andhousing policy issues in China. It focuses on China's urban housing systemand future housing policies Some of the main contexts to be discussed are:(1) the process and characterstics of housing development in new China, (2)the weaknesses of the old urban housing system; (3) reforms of the urbanhousing system; (4) China's housing markets in transition; (5) Current urbanhousing reform policy dilemmas; (6) experiences from developed countries;(7) main housing policy issues in the western world, and (8) ways to dealwith the dilemmas.

A GIS-Based Multicriteria Decision Analysis Approach for Mapping Accessibility Patterns of Housing Development Sites: A Case Study in Canmore, Alberta

This paper presents a Geographic Information System (GIS) based multicriteria decision analysis approach for mapping accessibility patterns of housing development sites in Canmore, Alberta. The approach involves integrating two multicriteria decision methods (Analytical Hierarchy Process and Ordered Weighted Aver-aging) in a raster GIS environment, and incorporating the linguistic quantifier concept as a method for ob-taining the order weights. The approach facilitates a wide range of location (decision) strategies to be gener-ated and examined. The aim of the study is to help the housing development authorities in addressing the uncertainty involved in the decision making process, achieving a better understanding of the alternative ac-cessibility patterns. It also assists the authorities in evaluating and prioritizing the potential housing devel-opment sites in terms of accessibility levels.

Barrier-free Design of Public Rental Housing

With the aging of society,special groups have had increasing needs of integrating into social life,and higher requirements on life quality,and the society has attached increasing importance to barrier-free design.Taking public rental housing for example,both circulation space and furniture design have to fully consider needs of special groups such as the seniors and the disabled.Barrier-free design in living spaces can help improve their ability of self-care,reduce their dependence on family members,fully demonstrate the"human-centered"design concept of public rental housing,and show the designers’sense of social responsibility.

Hedonic price analysis of urban housing:An empirical research on Hangzhou,China

The hedonic price model is widely applied to study the urban housing market because of the heterogeneity of housing products. Literature indicated that the hedonic price theory mainly includes two parts: Lancaster’s partiality theory and Rosen’s characteristic market equilibrium analysis. This paper chose 18 characteristics as independent variables and set up a linear hedonic price model for Hangzhou City. The model was tested with 2473 housing samples and field survey data of 290 housing commu-nities. This research found that 14 out of 18 characteristics had significant influence on housing price. They were classified into 5 groups according to their impact degree.