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.

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.

Practical Research on Promoting the Reform of“One Field for One Household”in Guoyang County

In recent years,the problem of farmland fragmentation has become a major obstacle to the development of modern agriculture,and the reform of“one field for one household”can effectively sort out cultivated land resources,increase contracted land area,improve land utilization rate,and effectively solve the problems of contracted land dispersion and farmland fragmentation in rural areas.This paper systematically anatomized the practice and effects of“one household,one field”reform in Guoyang County,analyzed the problems existing in the implementation process,and put forward corresponding suggestions and countermeasures,in order to provide experience and reference for the reform of one field in other regions.

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.

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.

E-house箱体及吊具的吊装过程受力数值计算

预装式变电站(E-house)作为电网重要的电能传输枢纽,已经被广泛应用。在安装施工过程中,箱体质量、吊具结构、吊装速度等因素均会引起箱体形变的发生,导致设备的损坏。为了解决该问题,对所设计的9.8 m×3.2 m尺寸的E-house箱体及吊具结构进行吊装受力分析,并利用有限元方法分析了吊装结构和箱体的应力变形,确定了吊具和箱体易变形损坏部位。计算结果表明,为减少轴向压力对吊具的影响,钢丝绳安全夹角应控制在60°以内,安全的吊装速度应控制在1 m/s以下。研究结果可以为后续的箱体结构设计与优化提供理论参考。

The Challenges in Providing Affordable Housing in Nigeria and the Adequate Sustainable Approaches for Addressing Them

Despite multiple schemes implemented by various governments around the country, affordable housing remains elusive to the average Nigerian. Because the situation is comparable to that of other developing nations, it remains a key concern in these countries’ socioeconomic development. Over 52% of Nigeria’s population has been claimed to live in shanties, squatter communities, and informal settlements. This article, therefore, reviews the challenges to the provision of affordable housing in Nigeria and the Sustainable approaches to address them. The article’s findings were based on a thorough examination of the literature. The article’s findings indicated that sustainable approaches for addressing Nigeria’s affordable housing barriers may best be examined through the economic, ecological, social, institutional, and technical factors. The paper urges the present regime, investors, lawmakers, and private developers in Nigeria to implement these approaches for affordable housing provision. The findings from this article will add to the current body of knowledge by providing important information on affordable housing provision and re-directing research interest towards affordable housing in Nigeria and other developing countries.

The Benefits of Solar Energy on the Provision of Sustainable Affordable Housing in Nigeria

Solar energy is the most abundant form of energy on Earth. Solar energy brings impactful benefits and products that are expected to make homes more reliable, sustainable, and affordable. Thanks to technological advancements like the solar cell, we can gather this energy and turn it into electricity. The construction industry has an exceptional chance of benefiting from this sustainable energy. Many recognised benefits have been spelled forth in the construction industry, such as providing homes with clean energy with no trace of ozone depleting material emission. There are many people in Nigeria who are not linked to the public electric grid, and the energy sector produces and generates less than 58% of the entire amount of energy required. As stated in the Nigeria’s National Energy General Plan, the Sustainable Energy programme aims to enhance the country’s use of solar electricity. This paper focuses on the role of solar energy in the provision of sustainable affordable housing in Nigeria. It considers the description, method, and utilisation of solar energy with a focus on residential and commercial buildings.

Assessment of Compliance to Building Energy Efficiency Strategies in the Development of Housing Estates in FCC, Abuja Nigeria

Compliance to local energy efficiency strategies can significantly reduce energy consumption in buildings and promote sustainability. However, Nigeria Building Energy Efficiency Code (BEEC) seems to be just paper work without enforcement or compliance. Assessment of Compliance to Green Building Energy Efficiency Strategies in the Development of Housing Estates in FCC, Abuja Nigeria was carried out. The compliance of estate buildings to BEEC in the study area was assessed;and the aspects of the building energy efficiency strategies with more compliance were determined. Data were mainly from primary sources such as questionnaire survey, interview with key informants and observation. The study population included all estate developers and building construction professionals. Data were gathered from one hundred and fifty (150) building professionals through questionnaire administration. Data collected were analysed using Z score and ANOVA and presented in tables. Results show that only 18% of respondents agreed that building complied with BEEC, and the Z score for positive affirmation is below average score. There is a significant difference in the integration of different energy efficient management strategies in the estates’ construction at 95% confidence level. The integration of measures such as window to wall ratio and window shading’ were significantly higher than other BEEC strategies such as roof insulation and minimal air condition unit (≤EER/COP of 2.8). Thus, the development of estates in FCC Abuja did not achieve energy efficiency.

Identifying Spatial Heterogeneity in the Effects of High-Tech Firm Density on Housing Prices:Evidence from Guangdong-Hong Kong-Macao Greater Bay Area,China

Innovation capitalization is a new concept in innovation geography research.Extant research on a city scale has proven that innovation is an important factor affecting housing prices and verified that innovation has a capitalization effect.However,few studies investigate the spatial heterogeneity of innovation capitalization.Thus,case verification at the urban agglomeration scale is needed.Therefore,this study proposes a theoretical framework for the spatial heterogeneity of innovation capitalization at the urban agglomeration scale.Examining the Guangdong-Hong Kong-Macao Greater Bay Area(GHMGBA),China as a case study,the study investigated the spatial heterogeneity of the influence of high-tech firms,representing innovation,on housing prices.This work verified the spatial heterogeneity of innovation capitalization.The study constructed a data set influencing housing prices,comprising 11 factors in 5 categories(high-tech firms,convenience of living facilities,built environment,the natural environment,and the fundamentals of the districts)for 419 subdistricts in the GHMGBA.On the global scale,the study finds that high-tech firms have a significant and positive influence on housing prices,with the housing price increasing by 0.0156%when high-tech firm density increases by 1%.Furthermore,a semi-geographically weighted regression(SGWR)analysis shows that the influence of high-tech firms on housing prices has spatial heterogeneity.The areas where high-tech firms have a significant and positive influence on housing prices are mainly in the GuangzhouFoshan metropolitan area,western Shenzhen-Dongguan,north-central Zhongshan-Nansha district,and Guangzhou—all areas with densely distributed high-tech firms.These results confirm the spatial heterogeneity of innovation capitalization and the need for further discussion of its scale and spatial limitations.The study offers implications for relevant GHMGBA administrative authorities for spatially differentiated development strategies and housing policies that consider the role of innovation in successful urban development.

An Assessment of Housing Market Renewal in East Lancashire

The paper analyses the impact of the Government Housing Market Renewal(HMR)programme in the UK.It focuses on Burnley,East Lancashire,and on the inner-city neighbourhood of Burnley Wood.The aim of the programme was to rebalance the housing market in places suffering shrinkage.The intention was to renew failing housing markets and reconnect them to regional markets,to improve neighbourhoods and to encourage people to live and work in these areas.One of these was East Lancashire and the author visited Burnley,one of its principal towns,in 2005,as part of a CABE study.The paper describes the Pathfinding policy,the actions being taken and the community's reaction.The author recently returned to Burnley and spoke to some of the same people reported in 2005.This paper documents what has been achieved in the past 7 years.

Architecture as a Means of Developing Social Exchange:Learning from a Danish Case Study of Refurbishment and Urban Transformation in a Disadvantaged Housing Area

Disadvantaged housing areas from the postwar period typically consist of relatively monotonous and monofunctional multi-storey blocks and have a separate traffic system rendering the areas isolated enclaves in the urban fabric.It is argued that this spatial isolation contributes to social isolation,and current refurbishments are therefore aimed at linking the housing areas with the surrounding neighbourhoods to enable social exchange between the residents and people from the surrounding areas.Based on a case study in a Danish social housing area,this paper discusses to what extent architectural development and urban strategic transformations can contribute to enabling social exchange in disadvantaged housing areas.Do neighbours enter the disadvantaged housing area as intended?If so,how does this influence their perception of the housing area?The analysis shows that architectural development and urban transformations are interdependent in establishing a social mix in disadvantaged housing areas.It is argued that refurbishments can reduce the stigma surrounding the housing area and its residents.However,the applicability of such strategies is highly dependent on the local context of the housing area.

Characterization,identification and life prediction of acoustic emission signals of tensile damage for HSR gearbox housing material

Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional tests of mechanical property can hardly meet this requirement.Design/methodology/approach-In this study the acoustic emission(AE)technology is applied in the tensile tests of the gearbox housing material of an high-speed rail(HSR)train,during which the acoustic signatures are acquired for parameter analysis.Afterward,the support vector machine(SVM)classifier is introduced to identify and classify the characteristic parameters extracted,on which basis the SVM is improved and the weighted support vector machine(WSVM)method is applied to effectively reduce the misidentification of the SVM classifier.Through the study of the law of relations between the characteristic values and the tensile life,a degradation model of the gearbox housing material amid tensile is built.Findings-The results show that the growth rate of the logarithmic hit count of AE signals and that of logarithmic amplitude can well characterize the stage of the material tensile process,and the WSVM method can improve the classification accuracy of the imbalanced data to above 94%.The degradation model built can identify the damage occurred to the HSR gearbox housing material amid the tensile process and predict the service life remains.Originality/value-The results of this study provide new concepts for the life prediction of tensile samples,and more further tests should be conducted to verify the conclusion of this research.

Upcycling municipal solid waste to sustainable hydrogen via two-stage gasification-reforming

As global municipal solid waste(MSW)quantities continue to escalate,serious socio-environmental challenges arise,necessitating innovative solutions.Waste-to-hydrogen(WTH)via two-stage gasification-reforming(TSGR)presents an emergent technology for MSW upcycling,offering to ease waste management burdens and bolster the burgeoning hydrogen economy.Despite early initiatives to advance TSGR technology,a cohesive and critical analysis of cutting-edge knowledge and strategies to enhance hydrogen production remains lacking.This review aggregates literature on MSW upcycling to hydrogen via TSGR,with a focus on optimizing process control and catalytic efficiency.It underscores technological avenues to augment hydrogen output,curtail catalyst costs,and refine system performance.Particularly,the review illuminates the potential for integrating chemical and calcium looping into TSGR processes,identifying opportunities,and pinpointing challenges.The review concludes with a summary of the current state of techno-economic analysis for this technology,presenting outstanding challenges and future research directions,with the ultimate goal of transitioning WTH from theoretical to practical application.

Probabilistic Pre-requisites Contributing to Successful Housing Association Partnering

The necessity to achieve value for money(VFM)has been paramount during the current economic climate,with reductions in investment inducing Housing Associations(HAs)to minimise waste and pursue the maximisation of value.Differing characteristics between HAs and private sector clients have a bearing on the pre-requisites associated with a successful partnering outcome.The purpose of this paper is to assist HAs maximise VFM by increasing the likelihood of a successful partnering outcome through gaining an understanding of the most important pre-requisites to be implemented into the arrangement from a HA perspective.A quantitative analysis was adopted to identify the level of importance placed by HA on the probabilistic pre-requisites that contribute to a successful partnering outcome.The results highlight the most important probabilistic pre-requisites from a HA perspective.The research concluded that the three most importantly ranked pre-requisites that contribute to a successful partnering arrangement,perceived exclusively by HAs,were mutual trust between parties;stakeholder commitment and mutual objectives.The plethora of construction partnering research is predominantly based on the construction industry generally.This research focuses on the specific needs of HAs.The findings therefore enable HAs to differentiate between the most and least important pre-requisites identified within the literature.This will increase the probability of a successful partnering arrangement through the unveiling of the pre-requisites that HAs should focus on implementing.Subsequently,the research will assist HAs maximise VFM during the challenging economic period where investment into social housing has been reduced.

Mass Customization and Design for High Density Indemnificatory Housing in China

The use of computer in architectural design shouldn’t sacrifice the pursuit of a human-oriented built environment.The technological applications should be legitimated by the objectives and motivations in multiple dimensions,but not abuse its generative power against the social and cultural interests.This article is based upon our synthetic computational design research for high density indemnificatory housing in China(Fig.1),which challenges the conventional standard design for large scale social housing in the Industrial Era,and reflects our exploration for innovative,multi-disciplinary,systematic and synthetic design in the new design paradigm of computation.It also promotes to shift the privilege of cutting-edge design techniques and avant-garde concepts from the“High(end)Architecture”to the ordinary architecture during the unprecedented built-environment development in China.Architectural design should have no discrimination between the Olympic stadiums in the capital and the social housing in the subordinate developed cities,as they both need to be innovative and meaningful.The final design research outputs address sustainable transformation initiated by the residents during the whole life span of the housing.We believe that the human factor(including stakeholders,users,designers and builders)is even more important in architectural design,city planning,urban design,landscape and interior design while technology development is accelerating.Conceptualization,imagination and systemization would become significant pacemakers which perpetuate design innovation.

Methanol steam reforming for hydrogen production driven by an atomically precise Cu catalyst

Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can be used as light-harvesting materials in solar energy utilization such as photocatalytic methanol steam reforming.In this work,we report an atomically precise Cu_(13)cluster protected by dual ligands of thiolate and phosphine that can be viewed as the assembly of one top Cu atom and three Cu_(4)tetrahedra.The Cu_(13)H_(10)(SR)_(3)(PR’_(3))_(7)(SR=2,4-dichlorobenzenethiol,PR’_(3)=P(4-FC_(6)H_(4))_(3))cluster can give rise to highly efficient light-driven activity for methanol steam reforming toward H_(2)production.

Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16

To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.