Travel behaviour and mobility needs of older adults in an ageing and car-dependent society

Jianqiang Cui,Becky P. Y. Loo,Dong Lin 서울시립대학교 도시과학연구원 2017 도시과학국제저널 Vol.21 No.3

An ageing population poses long-term challenges for a nation’s health, labour force market, housing and transport, affecting economic growth, living standards and government finances. With increasingly rapid ageing in both developed and developing countries, how to develop future transport frameworks, taking into account the increasingly large ageing population and their travel needs, has been emerging as a major challenge in urban policy development. This review explores how demographic changes in an ageing society and the associated travel patterns of a changing older cohort may impact on future transport demand by providing evidence on the travel behaviour of older adults, its associated influencing factors and the possible alternatives to car transport for older adults. It concludes by discussing major policy areas for addressing the elderly’s mobility needs via the provision of future transport infrastructure and services, implementing legislative and institutional approaches, and building accessible mobility environments. The paper also identifies key directions for further research.

Target alignment method of inertial confinement fusion facility based on position estimation

Lin Weiheng,Zhu Jianqiang,Liu Zhigang,Pang Xiangyang,Zhou Yang,Cui Wenhui,Dong Ziming 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.10

Target alignment technology is one of the most critical technologies in laser fusion experiments and is an important technology related to the success of laser fusion experiments. In this study, by combining the open-loop and closed-loop errors of the target alignment, the Kalman state observer is used to estimate the position of the target, which improves the observation precision of the target alignment. Then the optimized result is used to guide the alignment of the target. This method can greatly optimize the target alignment error and reduce uncertainty. With the improvement of the target alignment precision, it will greatly improve the reliability and repeatability of the experiments’ results, thereby improving the success rate of the experiments.

The perception of accessibility and ease of orientation of underground pedestrian systems: a survey in Shanghai

Jianqiang Cui,Andrew Allan,Michael A.P. Taylor,Dong Lin 서울시립대학교 도시과학연구원 2012 도시과학국제저널 Vol.16 No.3

Dominant modes of transport in city centres have a significant influence on urban morphology, land usage, the character of the urban environment and people’s life style. Improving accessibility, continuity, safety, availability and connectivity for pedestrians has critical importance as a means of decreasing vehicle usage and increasing public transport usage. Within the city centres of the mega cities,underground pedestrian systems (UPS) have been used to integrate pedestrian traffic in transport systems as a redevelopment strategy to provide additional space resources for multiple functions, such as commercial and public activities. With the recent economic success in China, the research relating to the impact on urban environments remains lacking, and this challenges the successful development of UPS in the future. Three UPS in Shanghai were subjected to a detailed investigation to understand the impact of the UPS, especially from the perspective of the users’ perception. Data were obtained from on-the-spot observations, face to face questionnaires with the UPS users, and interviews with an academic, a coordinator of a UPS project and two UPS managers. The research integrated both qualitative and quantitative methods, which analyzed the issues relating to accessibility and ease of orientation with the UPS. The research revealed that as an important component of central urban area pedestrian systems, the UPS have limited functionality to its users and are not fully utilized by the general public. The research focused on Shanghai’s expanding constellation of UPS, which has previously lacked discussion in the literature.

Sub-centres, socio-economic characteristics and commuting: a case study and its implications

Dong Lin,Andrew Allan,Jianqiang Cui 서울시립대학교 도시과학연구원 2017 도시과학국제저널 Vol.21 No.3

Institutional and economic reforms in China have not only delivered major improvements in people’s living standards but also changed the spatial structure of Chinese cities. In addition, substantially increased commuting times have become a serious problem influencing quality of life in the mega-cities of China. Accordingly, research into the dynamics of urban restructuring in rapidly growing Chinese cities and the impacts on workers’ commuting patterns would provide important evidence in this research field. The results of this case study suggest that polycentric urban development has a significant influence on employees’ commuting times. Promoting local jobs-housing balance in sub-centres would shorten commuting times for workers. The findings also suggest that the locations and types of employment centres are significantly associated with individuals’ choice of housing and workplace locations, and accordingly their commuting behaviour. The effects of decentralization of employment on workers’ commuting times differ depending on the extent of suburbanization of different economic sectors. The findings in this research also suggest that workers’ commuting behaviour is related to individual socio-economic characteristics, such as income and education.

The impacts of urban spatial structure and socio-economic factors on patterns of commuting: a review

Dong Lin,Andrew Allan,Jianqiang Cui 서울시립대학교 도시과학연구원 2015 도시과학국제저널 Vol.19 No.2

Previous studies have reported that urban spatial structure and the spatial relationship between jobs and housing are strongly correlated with commuting patterns. Nevertheless, a number of studies have also supported the concept that the spatial relationship between workplaces and residences cannot be the only reason behind observed commuting behaviour. Some ‘soft’ factors also affect people's commuting patterns. When considering these ‘soft’ factors, urban land development patterns such as urban structure and the spatial relationship between jobs and housing must not be overlooked. In this paper, we first conduct a brief review of the debate about how urban spatial structure and the jobs–housing relationship affect commuting patterns. Then we mainly focus on the ‘soft’ factors related to commuting behaviour. We divided the ‘soft factors’ into city-level factors and individual- and household-level factors. These perspectives will offer insights to identify a set of key factors that could affect the patterns of commuting.

Competitive Adsorption of Binary Mixture of Leptospirillum ferriphilum and Acidithiobacillus caldus Onto Pyrite

Jian Song,Jianqun Lin,Jianqiang Lin,Yilin Ren 한국생물공학회 2010 Biotechnology and Bioprocess Engineering Vol.15 No.6

Leptospirillum ferriphilum and Acidithiobacillus caldus are two important acidophilic microorganisms involved in iron and sulfur oxidation during bioleaching. Cell adsorption to mineral surfaces is important for the direct leaching or contact leaching of minerals. In this study, we report the competitive adsorption of binary mixtures of L. ferriphilum LF-104 and A. caldus MTH-04onto pyrite surfaces. The Langmuir adsorption parameter (CAm) indicated that these two bacteria underwent competitive adsorption to pyrite. Real-time quantitive PCR was used to quantify the relative amounts of L. ferriphilum and A. caldus adsorbed onto the surfaces of pyrite following exposure to a mixture of these two organisms. The adsorption of L. ferriphilum was not affected by A. caldus. However, adsorption of A. caldus was greatly affected by the presence of L. ferriphilum. Zeta-potential measurements and FT-IR spectroscopic studies showed that L. ferriphilum had a higher electrostatic attraction towards pyrite when compared to A. caldus. Based on the above results, we propose a competitive adsorption model to explain the mechanism by which L. ferriphilum and A. caldus compete in their adsorption to pyrite, although L. ferriphilum dominated in the competitive adsorption process. This work provides a better understanding of the adsorption behavior of mixed microbial populations onto mineral surfaces.

Thermal deformation prediction for spindle system of machining center based on multi-source heterogeneous information fusion

Yushen Chen,Xiaolei Deng,Xiaoliang Lin,Shupeng Guo,Shaofei Jiang,Jianqiang Zhou 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.8

In order to predict the thermal deformation of CNC machine tool spindle system more accurately, a method based on multi-source heterogeneous information fusion is proposed. Aiming at the problem that it is difficult to obtain the global information of thermal deformation with a single type of information source, the effective prediction of thermal deformation of spindle system in machining center is realized under the fusion of temperature and vibration signals. First, the combined denoising method of empirical mode decomposition (EMD) and wavelet threshold is used to preprocess the vibration data. Then, the time-domain, frequencydomain, and time-frequency features of vibration signals are extracted, and the feature dimension is reduced based on correlation analysis and kernel principal component analysis (KPCA). After dimensionality reduction, the vibration data and temperature information are fused in the eigenmatrix. The nonlinear prediction of thermal deformation is studied by support vector regression for grid search parameter optimization (GS-SVR) and support vector regression for particle swarm optimization (PSO-SVR) methods. In order to realize the information acquisition of multi-channel temperature, vibration, and verify the effectiveness of the prediction model in the case of information fusion, a specific machining center is taken as the research object and experiments are performed based on multi-channel and heterogeneous signal acquisition. Finally, the prediction results based on different information sources are compared and analyzed. The results show that the thermal deformation of the machine tool obtained by the multi-source heterogeneous information fusion method is consistent with the actual test results. As compared with the predicted performance using only temperature information, the mean square error (MSE) decreased by 0.1663 μm. Therefore, the temperature - vibration information fusion model has higher accuracy in terms of predicting the thermal deformation of the spindle system model.

Complete Genome of Leptospirillum ferriphilum ML-04 Provides Insight into Its Physiology and Environmental Adaptation

Shuang Mi,Jian Song,Yuanyuan Che,Huajun Zheng,Jianqiang Lin,Jianqun Lin 한국미생물학회 2011 The journal of microbiology Vol.49 No.6

Leptospirillum ferriphilum has been identified as the dominant, moderately thermophilic, bioleaching microorganism in bioleaching processes. It is an acidic and chemolithoautrophic bacterium that gains electrons from ferrous iron oxidation for energy production and cell growth. Genetic information about this microorganism has been limited until now, which has hindered its further exploration. In this study, the complete genome of L. ferripilum ML-04 is sequenced and annotated. The bacterium has a single circular chromosome of 2,406,157 bp containing 2,471 coding sequences (CDS), 2 rRNA operons, 48 tRNA genes, a large number of mobile genetic elements and 2 genomic islands. In silico analysis shows L. ferriphilum ML-04 fixes carbon through a reductive citric acid (rTCA) cycle, and obtains nitrogen through ammonium assimilation. The genes related to “cell envelope biogenesis, outer membrane” (6.9%) and “DNA replication, recombination and repair” (5.6%) are abundant, and a large number of genes related to heavy metal detoxification, oxidative and acidic stress defense, and signal transduction pathways were detected. The genomic plasticity, plentiful cell envelope components, inorganic element metabolic abilities and stress response mechanisms found the base for this organism’s survival in the bioleaching niche.