Search results for: Cheng Hong YEO

Authors: J. Mona, R. R. da Silva, C.-L.Cheng, Y. Kopelevich

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We report on a possible occurrence of superconductivity in 5 nm particle size diamond powders treated with sulfur (S) at 500 o C for 10 hours in ~10-2 Torr vacuum. Superconducting-like magnetization hysteresis loops M(H) have been measured up to ~ 50 K by means of the SQUID magnetometer (Quantum Design). Both X-ray (Θ-2Θ geometry) and Raman spectroscopy analyses revealed no impurity or additional phases. Nevertheless, the measured Raman spectra are characteristic to the diamond with embedded disordered carbon and/or graphitic fragments suggesting a link to the previous reports of the local or surface superconductivity in graphite- and amorphous carbon–sulfur composites.

Keywords: nanodiamond, sulfur, superconductivity, Raman spectroscopy

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Authors: C. H. Chang, R. Z. Qiu, C. W. Tsao, Y. H. Cheng, C. H. Chen, W. J. Hsueh

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Characteristics of photoluminescence (PL) in a resonant quasi-periodic double-period quantum wells (DPQW) are demonstrated. The maximum PL intensity in the DPQW is remarkably greater than that in a traditional periodic QW (PQW) under the Bragg or anti-Bragg conditions. The optimal PL spectrum in the DPQW has an asymmetrical form instead of the symmetrical form in the PQW. Moreover, there are two large values of PL intensity in the DPQW, which also differs from the PQW.

Keywords: Photoluminescence, quantum wells, quasiperiodic structure

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Authors: Tris Kee

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This research investigates social sustainability factors in transitional housing projects and their impact on fostering healthy living environments that promote physical activity and social interaction for residents. Social sustainability is integral to individual health and well-being, as emphasized by Goal 11 of the 2030 Agenda for Sustainable Development, which highlights the importance of safe, affordable, and accessible transport systems, green spaces, and public spaces catering to vulnerable populations' needs. Communal spaces in urban environments are essential for fostering social sustainability, as they serve as settings for physical activities and social interactions among diverse socio-economic groups. Factors such as neighborhood social atmosphere, historical context, social disparity, and mobility can influence the relationship between existing and transitional communities. Mental health effects can be measured through housing segregation, mobility and accessibility, and housing tenure. A significant research gap exists in understanding the living environment of transitional housing in Hong Kong and the social sustainability factors affecting residents' mental and physical health. To address this gap, our study employs a mixed-methods approach combining survey questionnaires and interviews to gather both quantitative and qualitative data. This methodology will provide comprehensive insights into residents' experiences and perceptions. Our research's main contribution is identifying key social sustainability factors in transitional housing and their impact on residents' well-being, informing policy-making and the creation of inclusive, healthy living environments. By addressing this research gap, we aim to provide valuable insights for future housing projects, ultimately promoting the development of socially sustainable transitional communities.

Keywords: social sustainablity, affordable housing, transitional housing, high density housing

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Authors: Yu-Yao Wang, Xiao-Meng Hu, Joanne Yeung, Xiao-Yan Li

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The high private cost and unquantified external cost limit the development of reclaimed water. In this study, an integrated framework comprising life cycle assessment (LCA), quantitative microbial risk assessment (QMRA), and life cycle costing (LCC) was developed to evaluate both costs of reclaimed water supply in water systems of various scales. LCA assesses the environmental impacts, and QMRA estimates the associated pathogenic impacts. These impacts are monetized as external costs and analyzed with the private cost by LCC to count the total life cycle cost. The framework evaluated the Hong Kong urban water system in the baseline scenario (BS) and five wastewater reuse scenarios (RS). They are RSI: substituting freshwater for toilet flushing only, RSII: substituting both freshwater and seawater for toilet flushing, RSIII: using reclaimed water for all non-potable uses, RSIV: using reclaimed water for all non-potable uses and indirect potable uses, and RSV: non-potable use and indirect potable use by conveying 100% reclaimed water to recharge the reservoirs. The results show that substituting freshwater and seawater for toilet flushing has the least total life cycle cost, exhibiting that it is the most cost-effective option for Hong Kong. Meanwhile, the evaluation results show that the external cost of each scenario is comparable to the corresponding private cost, indicating the importance of the inclusion of comprehensive external cost evaluation in private cost assessment of water systems with reclaimed water supply.

Keywords: life cycle assessment, life cycle costing, quantitative microbial risk assessment, water reclamation, reclaimed water, alternative water resources

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Authors: Kenny Chi Man Chui

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Background: In Chinese culture, the traditional equivalent term for English dementia is chi dai zheng, which, whether translated as ‘insanity’ or ‘idiocy’ carries a sharply negative connotation. In fact, even though the traditional name for dementia has evolved, from chi dai zheng to shi zhi zheng, nao tui hua zheng or ren zhi zhang ai zheng, educating the population about more respectful terms for the condition and promoting a positive understanding about people with dementia in society have proven to be time-intensive endeavors. By extension, the use of such terms promotes the perception that people with dementia undergo a ‘total loss of self’ or experience a ‘living death’ or ‘social death’. Both in Asia and elsewhere, the appropriate nomenclature for dementia remains controversial, and different medical and healthcare professionals in Hong Kong have taken various stances on how to refer to the condition there. Indeed, how this negative perception affects the interaction between people with dementia and the surrounding others? Methodology: Qualitative research with the concept of postmodernism, interpretivism, and Foucauldian theory was adopted as frameworks in applying participatory observations, in-depth interviews, and other qualitative methods. First, ten people with dementia—one man and nine women—living in two residential care homes in Hong Kong were interviewed, as were ten members of the care staff, all of whom were women. Next, to coach the staff in understanding the feelings and self-perceptions of people with dementia, two reflective training sessions were provided. Afterward, to assess the impact of the training sessions on the staff, two focus groups were held. Findings: The findings revealed that residents with dementia did not perceive themselves as being ‘demented’ and were confused by not getting responses from the others. From the understanding of care staff, they perceived the residents as being ‘demented’, desolate troublemakers. They described people with dementia as ‘naughty children’ who should be controlled and be punished while treated them as ‘psychiatric patients’ who could be ignored and be mute. “Psychosocial restraint” happened regarding the discrepancy of perception between people with dementia and the care staff. People with dementia did not think that their confusion of memory was related to dementia or, frankly speaking, they did not know what dementia was. When others treated them as ‘demented patients, the residents with mild to moderate dementia fiercely rejected that designation and reported a host of negative feelings, hence the fluctuations of mood and emotion noted by the care staff. Conclusion: As the findings revealed, the people with dementia were also discontent with the care arrangements in the care homes, felt abandoned by others and worried about bothering others. Their shifting emotional states and moods were treated as the Behavioral and Psychological symptoms of Dementia (BPSD), which nothing can do reported by the care staff in the residential care homes. People with dementia become social withdrawal or isolated in daily living, which should be alert and be changed by the social work professionals about the occurrence of “psychosocial restraint” in dementia care.

Keywords: psychosocial restraint, qualitative research, social work with dementitude, voice of people with dementia

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Authors: Wan-Ling Jiang, Hsin Chi, Jia-Lu Cheng, Ming-Fang Cheng

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Background: Investigating the risk factors for the fecal carriage of third-generation cephalosporin-resistant E.coli could contribute to further disease prevention. Previous research on third-generation cephalosporin-resistant prevalence in children in different regions of Taiwan is limited. This project aims to explore the risk factors and regional differences in the prevalence of third-generation cephalosporin-resistant and other antibiotic-resistant E. coli in the northern, southern, and eastern regions of Taiwan. Methods: We collected data from children aged 0 to 18 from community or outpatient clinics from July 2022 to May 2023 in southern, northern, and eastern Taiwan. The questionnaire was designed to survey the characteristics of participants and possible risk factors, such as clinical information, household environment, drinking water, and food habits. After collecting fecal samples and isolating stool culture with E.coli, antibiotic sensitivity tests and MLST typing were performed. Questionnaires were used to analyze the risk factors of third-generation cephalosporin-resistant E. coli in the three different regions of Taiwan. Results: In the total 246 stool samples, third-generation cephalosporin-resistant E.coli accounted for 37.4% (97/246) of all isolates. Among the three different regions of Taiwan, the highest prevalence of fecal carriage with third-generation cephalosporin-resistant E.coli was observed in southern Taiwan (42.7%), followed by northern Taiwan (35.5%) and eastern Taiwan (28.4%). Multi-drug resistant E. coli had prevalence rates of 51.9%, 66.3%, and 37.1% in the northern, southern, and eastern regions, respectively. MLST typing revealed that ST131 was the most prevalent type (11.8%). The prevalence of ST131 in northern, southern, and eastern Taiwan was 10.1%, 12.3%, and 13.2%, respectively. Risk factors analysis identified lower paternal education, overweight status, and non-vegetarian diet as statistical significance risk factors for third-generation cephalosporin-resistant E.coli. Conclusion: The fecal carriage rates of antibiotic-resistant E. coli among Taiwanese children were on the rise. This study found regional disparities in the prevalence of third-generation cephalosporin-resistant and multi-drug-resistant E. coli, with southern Taiwan having the highest prevalence. Lower paternal education, overweight, and non-vegetarian diet were the potential risk factors of third-generation cephalosporin-resistant E. coli in this study.

Keywords: Escherichia coli, fecal carriage, antimicrobial resistance, risk factors, prevalence

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Authors: Kin On Kwok, Vivian Wei, Benjamin Cowling, Steven Riley, Jonathan Read

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Background: The role of social contact behavior measured in different contact constructs in the transmission of respiratory pathogens with acute respiratory illness (ARI) remains unclear. We, therefore, aim to depict the individual pattern of ARI in the community and investigate the association between different contact dimensions and ARI in Hong Kong. Methods: Between June 2013 and September 2013, 620 subjects participated in the last two waves of recruitment of the population based longitudinal phone social contact survey. Some of the subjects in this study are from the same household. They are also provided with the symptom diaries to self-report any acute respiratory illness related symptoms between the two days of phone recruitment. Data from 491 individuals who were not infected on the day of phone recruitment and returned the symptom diaries after the last phone recruitment were used for analysis. Results: After adjusting different follow-up periods among individuals, the overall incidence rate of ARI was 1.77 per 100 person-weeks. Over 75% ARI episodes involve running nose, cough, sore throat, which are followed by headache (55%), malagia (35%) and fever (18%). Using a generalized estimating equation framework accounting for the cluster effect of subjects living in the same household, we showed that both daily number of locations visited with contacts and the number of contacts, explained the ARI incidence rate better than only one single contact construct. Conclusion: Our result suggests that it is the intertwining property of contact quantity (number of contacts) and contact intensity (ratio of subject-to-contact) that governs the infection risk by a collective set of respiratory pathogens. Our results provide empirical evidence that multiple contact constructs should be incorporated in the mathematical transmission models to feature a more realistic dynamics of respiratory disease.

Keywords: acute respiratory illness, longitudinal study, social contact, symptom diaries

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Authors: H. Al-Qassem, L. Cheng, Y. Pan

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In this paper, we establish sharp bounds for oscillatory singular integrals with an arbitrary real polynomial phase P. Our kernels are allowed to be rough both on the unit sphere and in the radial direction. We show that the bounds grow no faster than log (deg(P)), which is optimal and was first obtained by Parissis and Papadimitrakis for kernels without any radial roughness. Our results substantially improve many previously known results. Among key ingredients of our methods are an L¹→L² sharp estimate and using extrapolation.

Keywords: oscillatory singular integral, rough kernel, singular integral, orlicz spaces, block spaces, extrapolation, L^{p} boundedness

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Authors: Chiu-Yin Leung

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This research investigates a complex assemblage among indigenous identities, socio-political organization and national apparatus in the border landscape of post-colonial Hong Kong. This former British colony had designated a transient mode of governance in its New Territories and particularly the northernmost borderland in 1951-2012. With a discriminated system of land provisions for the indigenous villagers, the place has been inherited with distinctive village-based culture, historic monuments and agrarian practices until its sovereignty return into the People’s Republic of China. In its latest development imperatives by the national strategic planning, the frontier area of Hong Kong has been identified as a strategy site for regional economic integration in South China, with cross-border projects of innovation and technology zones, mega-transport infrastructure and inter-jurisdictional arrangement. Contemporary literature theorizes borders as the material and discursive production of territoriality, which manifest in state apparatus and the daily lives of its citizens and condense in the contested articulations of power, security and citizenship. Drawing on the concept of assemblage, this paper attempts to tract how the border regime and infrastructure in Hong Kong as a city are deeply ingrained in the everyday lived spaces of the local communities but also the changing urban and regional strategies across different longitudinal moments. Through an intensive ethnographic fieldwork among the borderland villages since 2008 and the extensive analysis of colonial archives, new development plans and spatial planning frameworks, the author navigates the genealogy of the border landscape in Ta Kwu Ling frontier area and its implications as the milieu for new state space, covering heterogeneous fields particularly in indigenous rights, heritage preservation, rural sustainability and regional economy. Empirical evidence suggests an apparent bias towards indigenous power and colonial representation in classifying landscape values and conserving historical monuments. Squatter and farm tenants are often deprived of property rights, statutory participation and livelihood option in the planning process. The postcolonial bureaucracies have great difficulties in mobilizing resources to catch up with the swift, political-first approach of the mainland counterparts. Meanwhile, the cultural heritage, lineage network and memory landscape are not protected altogether with any holistic view or collaborative effort across the border. The enactment of land resumption and compensation scheme is furthermore disturbed by lineage-based customary law, technocratic bureaucracy, intra-community conflicts and multi-scalar political mobilization. As many traces of colonial misfortune and tyranny have been whitewashed without proper management, the author argues that postcolonial justice is yet reconciled in this fragmented border landscape. The assemblage of border in mainstream representation has tended to oversimplify local struggles as a collective mist and setup a wider production of schizophrenia experiences in the discussion of further economic integration among Hong Kong and other mainland cities in the Pearl River Delta Region. The research is expected to shed new light on the theorizing of border regions and postcolonialism beyond Eurocentric perspectives. In reassembling the borderland experiences with other arrays in state governance, village organization and indigenous identities, the author also suggests an alternative epistemology in reconciling socio-spatial differences and opening up imaginaries for positive interventions.

Keywords: heritage conservation, indigenous communities, post-colonial borderland, regional development, rural sustainability

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Authors: J. Rhodes, V. Cheng, P. Lok

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The aim of this study is to develop a parsimonious model that explains the effect of different stimulus on a tourist’s intention to visit a new destination. The model consists of destination trust and interest as the mediating variables. The model was tested using two different types of stimulus; both studies empirically supported the proposed model. Furthermore, the first study revealed that advertising has a stronger effect than positive online reviews. The second study found that the peripheral route of the elaboration likelihood model has a stronger influence power than the central route in this context.

Keywords: advertising, electronic word-of-mouth, elaboration likelihood model, intention to visit, trust

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Authors: Yih-Chien Chen, Yu-Cheng You

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The microwave dielectric properties of La2MoO6 ceramics were investigated with a view to their application in mobile communication. La2MoO6 ceramics were prepared by the conventional solid-state method with various sintering conditions. The X-ray diffraction peaks of La2MoO6 ceramic did not vary significantly with sintering conditions. The average grain size of La2MoO6 ceramics increased as the temperature and time of sintering increased. A maximum density of 5.67 g/cm3, a dielectric constants (εr) of 14.1, a quality factor (Q×f) of 68,000 GHz, and a temperature coefficient of resonant frequency (τf) of -56 ppm/℃ were obtained when La2MoO6 ceramics that were sintered at 1300 ℃ for 4h.

Keywords: ceramics, sintering, microwave dielectric properties, La2MoO6

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Authors: Tak Mau Simon Chan, Ying Chuen Lance Chan

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Homelessness has been a popular and controversial debate in Hong Kong, a city which is densely populated and well-known for very expensive housing. The constitution of the homeless as threats to the community and environmental hygiene is ambiguous and debatable in the Hong Kong context. The lack of an intervention model is the critical research gap thus far, aside from the tangible services delivered. The life story approach (LSA), with its unique humanistic orientation, has been well applied in recent decades to depict the needs of various target groups, but not the homeless. It is argued that the life story approach (LSA), which has been employed by health professionals in the landscape of dementia, and health and social care settings, can be used as a reference in the local Chinese context through indigenization. This study, therefore, captures the viewpoints of service providers and users by constructing an indigenous intervention model that refers to the LSA in serving the chronically homeless. By informing 13 social workers and 27 homeless individuals in 8 focus groups whilst 12 homeless individuals have participated in individual in-depth interviews, a framework of LSA in homeless people is proposed. Through thematic analysis, three main themes of their life stories was generated, namely, the family, negative experiences and identity transformation. The three domains solidified framework that not only can be applied to the homeless, but also other disadvantaged groups in the Chinese context. Based on the three domains of family, negative experiences and identity transformation, the model is applied in the daily practices of social workers who help the homeless. The domain of family encompasses familial relationships from the past to the present to the speculated future with ten sub-themes. The domain of negative experiences includes seven sub-themes, with reference to the deviant behavior committed. The last domain, identity transformation, incorporates the awareness and redefining of one’s identity and there are a total of seven sub-themes. The first two domains are important components of personal histories while the third is more of an unknown, exploratory and yet to-be-redefined territory which has a more positive and constructive orientation towards developing one’s identity and life meaning. The longitudinal temporal dimension of moving from the past – present - future enriches the meaning making process, facilitates the integration of life experiences and maintains a more hopeful dialogue. The model is tested and its effectiveness is measured by using qualitative and quantitative methods to affirm the extent that it is relevant to the local context. First, it contributes to providing a clear guideline for social workers who can use the approach as a reference source. Secondly, the framework acts as a new intervention means to address problem saturated stories and the intangible needs of the homeless. Thirdly, the model extends the application to beyond health related issues. Last but not least, the model is highly relevant to the local indigenous context.

Keywords: homeless, indigenous intervention, life story approach, social work practice

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Authors: Li Cheng, Zhang Yilei, Cohen Yehuda

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Two motility mechanisms were introduced into iDynoMiCs software, which adopts an individual-based modeling method. Based on the new capabilities, along with the pressure motility developed before, influence of bacterial motility on biofilm formation was studied. Simulation results were evaluated both qualitatively through 3D structure inspections and quantitatively by parameter characterizations. It was showed that twitching motility increased the biofilm surface irregularity probably due to movement of cells towards higher nutrient concentration location whereas free motility, on the other hand, could make biofilms flatter and smoother relatively. Pressure motility showed no significant influence in this study.

Keywords: iDynoMics, biofilm structure, bacterial motility, motility mechanisms

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Authors: Nam Sze Cheng, P. C. Janita Chau

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Background: Eczema is a chronic inflammatory disease with high global prevalence rates in many childhood populations. It is also the most common paediatric skin problem. Although eczema education and proper skin care were effective in controlling eczema symptoms, the lack of both sufficient time for patient consultation and structured eczema education programme hindered the transferability of knowledge to patients and their parents. As a result, these young patients and their families suffer from a significant physical disability and psychological distress, which can substantially impair their quality of life. Objectives: This integrative review is to examine the effects of educational interventions for children with eczema and identify the core elements associated with an effective intervention. Methods: This integrative review targeted all articles published in 10 databases between May 2016 and February 2017 that reported the outcomes of disease interventions of any format for children and adolescents with the clinical diagnosis of eczema who were under 18 years of age. Five randomized controlled trials (RCT) and one systematic review of 10 RCTs were identified for review. All these publications had high methodological quality, except one study of web-based eczema education that was limited by selection bias and poor subject blinding. Findings: This review found that most studies adopted nurse-led or multi-disciplinary parental eczema education programme at the outpatient clinic setting. The format of these programmes included individual lectures, demonstration and group sharing, and the educational materials covered basic eczema knowledge and management as well as methods to interrupt itch-scratch cycle. The main outcome measures of these studies included severity of eczema symptoms, treatment adherence and quality of life of both patients and their families. Nine included studies reported statistically significant improvement in the primary outcome of symptom severity of these eczematous children. On the other hand, all these reviews failed to identify an effective dosage of intervention under these educational programmes that was attributed to the heterogeneity of the interventions. One study that was designed based on the social cognitive theory to guide the interventional content yielded statistically significant results. The systematic review recommended the importance of measuring parental self-efficacy. Implication: This integrative review concludes that structured educational programme can help nurses understand the theories behind different health interventions. They can then deliver eczema education to their patients in a consistent manner. These interventions also result in behavioral changes through patient education. Due to the lack of validated educational programmes in Chinese, it is imperative to conduct an RCT of eczema educational programme to investigate its effects on eczema severity, quality of life and treatment adherence in Hong Kong children as well as to promote the importance of parental self-efficacy.

Keywords: children, eczema, education, intervention

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Authors: Zijian Cheng, Frank Liu, Yupu Sun

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The relationship between the intensity of share pledging activities and the level of financial constraint in publicly listed firms in China is examined in this paper. Empirical results show that the high financial constraint level may motivate insiders to use share pledging as an alternative funding source and an expropriation mechanism. Share collateralization can cause a subsequently more constrained financing condition. Evidence is found that share pledging made by the controlling shareholder is likely to mitigate financial constraints in the following year. Research findings are robust to alternative measures and an instrumental variable for dealing with endogeneity problems.

Keywords: share pledge, financial constraint, controlling shareholder, dividend policy

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Authors: Sungjun Hong, Youah Lee, Jongwook Kim

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In the last COP21 held in Paris on 2015, Korean government announced that Intended Nationally Determined Contributions (INDC) was 37% based on BAU by 2030. The GHG reduction rate of the transportation sector is the strongest among all sectors by 2020. In order to cope with Korean INDC, Korean government established that 3rd eco-friendly car deployment national plans at the end of 2015. In this study, we make the energy system model for estimating GHG emissions using LEAP model.

Keywords: INDC, greenhouse gas, LEAP, transportation

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Authors: Shengjun Zhang, Xu Cheng, Feng Shen

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The passive containment cooling system (PCCS) is widely used in the advanced nuclear reactor in case of the loss of coolant accident (LOCA) and the main steam line break accident (MSLB). The internal heat exchanger is one of the most important equipment in the PCCS and its heat transfer characteristic determines the performance of the system. In this investigation, a theoretical model is presented for predicting the heat and mass transfer which accompanies condensation. The conduction through the liquid condensate is considered and the interface temperature is defined by iteration. The parameter in the correlation to describe the suction effect should be further determined through experimental data.

Keywords: non-condensable gas, condensation, heat transfer coefficient, heat and mass transfer analogy

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Authors: Yi-Cheng Tian, Miin-Shen Yang

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The mixture likelihood approach to clustering is a popular clustering method where the expectation and maximization (EM) algorithm is the most used mixture likelihood method. In the literature, the EM algorithm had been used for mixture regression models. However, these EM mixture regression algorithms are sensitive to initial values with a priori number of clusters. In this paper, to resolve these drawbacks, we construct a learning-based schema for the EM mixture regression algorithm such that it is free of initializations and can automatically obtain an approximately optimal number of clusters. Some numerical examples and comparisons demonstrate the superiority and usefulness of the proposed learning-based EM mixture regression algorithm.

Keywords: clustering, EM algorithm, Gaussian mixture model, mixture regression model

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Authors: Bin-Wen Lan, Ying-Xin Chen, Hsueh-Cheng Yang

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Liquefied petroleum gas is a fuel that has high octane number and low carbon number. This paper uses MSC-51 controller to investigate the effect of liquefied petroleum gas (LPG) on exhaust emissions for different engine speeds in a single cylinder, four-stroke and spark ignition engine. The results indicate that CO, CO2 and NOX exhaust emissions are lower with the use of LPG compared to the use of unleaded gasoline by using the developed controller. The open-loop in the LPG injection system was controlled by MCS-51 single chip. The results show that if a SI engine is operated with LPG fuel rather than gasoline fuel under the same conditions, significant reduction in exhaust emissions can be achieved. In summary, LPG has positive effects on main exhaust emissions such as CO, CO2 and NOX.

Keywords: LPG, control circuit, emission, MCS-51

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Authors: Qian Zhao, Shi-Qi Liu, Bo Guo, Zhi-Jun Cheng, Xiao-Yue Wu

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Cold standby redundancy is considered to be an effective mechanism for improving system reliability and is widely used in industrial engineering. However, because of the complexity of the reliability structure, there is little literature studying on the residual life of cold standby system consisting of complex components. In this paper, a simulation method is presented to predict the residual life of k-out-of-n cold standby system. In practical cases, failure information of a system is either unknown, partly unknown or completely known. Our proposed method is designed to deal with the three scenarios, respectively. Differences between the procedures are analyzed. Finally, numerical examples are used to validate the proposed simulation method.

Keywords: cold standby system, k-out-of-n, residual life, simulation sampling

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Authors: Il Ho Park, Joong Seob Lee, Sung Hun Kang, Jae-Min Shin, Il Seok Park, Seok Min Hong, Seok Jin Hong

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Introduction: The human microbiota is the aggregate of microorganisms, and the bacterial microbiome of the human digestive tract contributes to both health and disease. In health, bacteria are key components in the development of mucosal barrier function and in innate and adaptive immune responses, and they also work to suppress the establishment of pathogens. In human upper airway, the sinonasal microbiota might play an important role in chronic rhinosinusitis (CRS). The purpose of this study is to investigate the human upper airway microbiome in CRS patients and to compare the sinonasal microbiome of adults with children. Materials and methods: A total of 19 samples from 19 patients (Group1; 9 CRS in children, aged 5 to 14 years versus Group 2; 10 CRS in adults aged 21 to 59 years) were examined. Swabs were collected from the middle meatus and/or anterior ethmoid region under general anesthesia during endoscopic sinus surgery or tonsillectomy. After DNA extraction from swab samples, we analysed bacterial microbiome consortia using 16s rRNA gene sequencing approach (the Illumina MiSeq platform). Results: In this study, relatively abundance of the six bacterial phyla and tremendous genus and species found in substantial amounts in the individual sinus swab samples, include Corynebacterium, Hemophilus, Moraxella, and Streptococcus species. Anaerobes like Fusobacterium and Bacteroides were abundantly present in the children group, Bacteroides and Propionibacterium were present in adults group. In genus, Haemophilus was the most common CRS microbiome in children and Corynebacterium was the most common CRS microbiome in adults. Conclusions: Our results show the diversity of human upper airway microbiome, and the findings will suggest that CRS is a polymicrobial infection. The Corynebacterium and Hemophilus may live as commensals on mucosal surfaces of sinus in the upper respiratory tract. The further study will be needed for analysis of microbiome-human interactions in upper airway and CRS.

Keywords: microbiome, upper airway, chronic rhinosinusitis, adult and children

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Authors: Mabel Y. C. Yau, Roy C. F. Lai, Hugo Y. H. Or

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This study is a pilot surveillance of hygiene compliance and food microbial safety of both licensed and mobile vendors selling Chinese ready–to-eat snack foods in Hong Kong. The study reflects similar situations in running mobile food vending business on trucks. Hong Kong is about to launch the Food Truck Pilot Scheme by the end of 2016 or early 2017. Technically, selling food on the vehicle is no different from hawking food on the street or vending food on the street. Each type of business bears similar food safety issues and cast the same impact on public health. Present findings demonstrate exemplarily situations that also apply to food trucks. 9 types of Cantonese style snacks of 32 samples in total were selected for microbial screening. A total of 16 vending sites including supermarkets, street markets, and snack stores were visited. The study finally focused on a traditional snack, the steamed rice cake with red beans called Put Chai Ko (PCK). PCK is a type of classical Cantonese pastry sold on push carts on the street. It used to be sold at room temperature and served with bamboo sticks in the old days. Some shops would have them sold steam fresh. Microbial examinations on aerobic counts, yeast, and mould, coliform, salmonella as well as Staphylococcus aureus detections were carried out. Salmonella was not detected in all samples. Since PCK does not contain ingredients of beef, poultry, eggs or dairy products, the risk of the presence of Salmonella in PCK was relatively lower although other source of contamination might be possible. Coagulase positive Staphylococcus aureus was found in 6 of the 14 samples sold at room temperature. Among these 6 samples, 3 were PCK. One of the samples was in an unacceptable range of total colony forming units higher than 105. The rest were only satisfactory. Observational evaluations were made with checklists on personal hygiene, premises hygiene, food safety control, food storage, cleaning and sanitization as well as waste disposals. The maximum score was 25 if total compliance were obtained. The highest score among vendors was 20. Three stores were below average, and two of these stores were selling PCK. Most of the non-compliances were on food processing facilities, sanitization conditions and waste disposal. In conclusion, although no food poisoning outbreaks happened during the time of the investigation, the risk of food hazard existed in these stores, especially among street vendors. Attention is needed in the traditional practice of food selling, and that food handlers might not have sufficient knowledge to properly handle food products. Variations in food qualities existed among supply chains or franchise eateries or shops. It was commonly observed that packaging and storage conditions are not properly enforced in the retails. The same situation could be reflected across the food business. It did indicate need of food safety training in the industry and loopholes in quality control among business.

Keywords: cantonese snacks, food safety, microbial, hygiene, street food

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Authors: Chi-Yan Chu, Kai-Chi Chuang, Huang-Chung Cheng

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In this study, the RRAM devices with the TiN/Ti/HfO_x/TiN structure were fabricated, then the electrical characteristics of the devices without annealing and after 400 °C and 500 °C of the furnace annealing (FA) temperature processes were compared. The RRAM devices after the FA’s 400 °C showed the lower forming, set and reset voltages than the other devices without annealing. However, the RRAM devices after the FA’s 500 °C did not show any electrical characteristics because the TiN/Ti/HfO_x/TiN device was oxidized, as shown in the XPS analysis. From these results, the RRAM devices after the FA’s 400 °C showed the best electrical characteristics.

Keywords: RRAM, furnace annealing (FA), forming, set and reset voltages, XPS

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Authors: Qianjia Cheng, Hongquan Jiang

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Crowdsourcing solves the problems that computers can't handle by integrating computers and the Internet. Its extensive knowledge sources, high efficiency and high quality, make crowdsourcing attract wide attention in industry and academia in recent years. The development of online crowdsourcing platforms such as Clickworker and Amazon Mechanical Turk(Mturk) tend to mature gradually. This paper sorts out the concept of crowdsourcing, sorts out the workflow of competitive crowdsourcing, summarizes the related technologies of crowdsourcing based on the workflow, quality control, cost control and delay control, introduces the typical crowdsourcing platform. Finally, we highlight some open problems of the current crowdsourcing and present some future research direction in this area.

Keywords: application, crowdsourcing, crowdsourcing platform, system architecture

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Authors: Cheng-Yen Huang, Yu-Jen Shih, Ming-Chun Yen, Yao-Hui Huang

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This research developed a fluidized-bed homogeneous crystallization (FBHC) process to remove copper from synthetic wastewater in terms of recovery of highly pure malachite (Cu2(OH)2CO3) pellets. The experimental parameters of FBHC which included pH, molar ratio of copper to carbonate, copper loading, upper flowrate and bed height were tested in the absence of seed particles. Under optimized conditions, both the total copper removal (TR) and crystallization ratio (CR) reached 99%. The malachite crystals were characterized by XRD and SEM. FBHC was capable of treating concentrated copper (1600 ppm) wastewater and minimizing the sludge production.

Keywords: copper, carbonate, fluidized-bed, crystallization, malachite

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Authors: Yuan-Hong Ho, Chiung-Ju Huang

Abstract:

This article presents a monitoring indicators system that predicts whether a local government in Taiwan is heading for fiscal distress and identifies a suitable fiscal policy that would allow the local government to achieve fiscal balance in the long run. This system is relevant to stockholders’ interest, simple for national audit bodies to use, and provides an early warning of fiscal distress that allows preventative action to be taken.

Keywords: fiscal health, fiscal distress, monitoring signals, 10-point scale

Procedia PDF Downloads 463

Authors: Jianguo Huang, Hong Cai, Bin Dong, Jifang Tao, Aiqun Liu, Dim-Lee Kwong, Yuandong Gu

Abstract:

We developed a miniaturized tunable optomechanical oscillator based on the nanoelectromechanical systems (NEMS) technology, and its frequencies can be electrostatically tuned by as much as 10%. By taking both advantages of optical and electrical spring, the oscillator achieves a high tuning sensitivity without resorting to mechanical tension. In particular, the proposed high-Q optical cavity design greatly enhances the system sensitivity, making it extremely sensitive to the small motional signal.

Keywords: nanoelectromechanical systems (NEMS), nanotechnology, optical force, oscillator

Procedia PDF Downloads 501

Authors: An-Shik Yang, Chin-Ting Kuo, Yung-Chun Yang, Wen-Hsin Hsieh, Chiang-Ho Cheng

Abstract:

Optical biosensors have become a powerful detection and analysis tool for wide-ranging applications in biomedical research, pharmaceuticals and environmental monitoring. This study carried out the computational fluid dynamics (CFD)-based simulations to explore the dispersion phenomenon in the microchannel of a optical biosensor. The predicted time sequences of concentration contours were utilized to better understand the dispersion development occurred in different geometric shapes of microchannels. The simulation results showed the surface concentrations at the sensing probe (with the best performance of a grating coupler) in respect of time to appraise the dispersion effect and therefore identify the design configurations resulting in minimum dispersion.

Keywords: CFD simulations, dispersion, microfluidic, optical waveguide sensors

Procedia PDF Downloads 550

Authors: Hyun-Seok Hong, In-Gun Kim, Ye-Jun Oh, Ju Lee

Abstract:

This paper deals with the effects of welding performed for the manufacture of laminations in a stator in the case of prototype motors that are manufactured in small quantity. As a result of performing the no-load test for an IPM (interior permanent magnet)-type BLDC (blushless direct current) motor manufactured by welding both inside and outside of the stator, it was found that more DC input than expected was provided. To verify the effects of welding, a stator was re-manufactured by bonding, and DC inputs provided during the no-load test were compared.

Keywords: welding, stator, Eddy current, BLDC

Procedia PDF Downloads 566

Authors: N. Li, Y. M. Cheng

Abstract:

In this paper, the classical bearing capacity problem is re-considered from discrete element analysis. In the discrete element approach, the bearing capacity problem is considered from the elastic stage to plastic stage to rupture stage (large displacement). The bearing capacity failure mechanism of a strip footing on soil is investigated, and the influence of micro-parameters on the bearing capacity of soil is also observed. It is found that the distinct element method (DEM) gives very good visualized results, and basically coincides well with that derived by the classical methods.

Keywords: bearing capacity, distinct element method, failure mechanism, large displacement

Procedia PDF Downloads 371