• Title/Summary/Keyword: Deterioration factors

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A Study on the Influence of Urban Environment on the Generation of Thermal Diseases (도시 환경이 온열질환 발생에 미치는 영향에 관한 연구)

  • Lee, Su-Mi;Kweon, Ihl;Kim, Yong-Jin
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.84-92
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    • 2019
  • The deterioration of the urban heat environment due to climate change and the occurrence of heat-related diseases have emerged as one of the major social problems. This has led to more research on climate change, including heat waves, but it is mainly focused on climate factors. However, the urban heat island phenomenon accelerates the summer heat wave, and the increasing trend of heat-related patients in urban areas suggests the impact of the city's environment. Thus, this study analyzed the effects of physical and social characteristics of urban areas on heat-related patients in Seoul and Gyeonggi-do. The analysis showed that the ratio of the total area of residential, commercial and industrial facilities, the main source of heat energy locality, among the land use statuses, was not statistically significant, but the road area and the green area were found to have a positive and negative The population density and the percentage of people aged 65 or older, the percentage of people living alone and the proportion of people receiving basic living were all shown to be significant, with only the ratio of elderly living alone and the ratio of population density having negative effects. The results of the study can be used to develop urban policy alternatives related to local warming patients.

A Study on the Improvement of Stretchability of Mozzarella Cheese (모짜렐라 치즈의 신전성 향상에 관한 연구)

  • 박희경;최수임;허태련
    • Food Science of Animal Resources
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    • v.24 no.2
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    • pp.156-163
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    • 2004
  • This study was carried out to investigate the improvement of stretchability in Mozzarella cheese based on the influence of various factors such as starter type, fat content, salt content and stretching temperature. To do this study, stretchability, meltability, fat leakage and the change of soluble nitrogen compound were measured during storage of the Mozzarella cheese at 4$^{\circ}C$ for 10 weeks. When L bulgaricus starter was added, stretchability of the cheese was excellent and cheese manufactured with starter of L bulgaricus and L. bulgaricus : Str. thermophilus = 1:2 improved meltability because of high soluble nitrogen compound. When salt content of cheese was 0.5%, this resulted in extreme deterioration of quality in regard to stretchability, meltability and fat leakage at five weeks and when salt content of cheese was 0.5, 1.0 and 1.5%, soluble nitrogen compound was 4.49, 4.45 and 2.61 % at one week and 19.71, 19.44% and 17.07% at eight weeks, respectively. Stretchability was good at high stretching temperature, and cheese with stretching at 60'C showed poor meltability at the first stage, but this cheese had good meltability in process of time because increase in soluble nitrogen compound was high at low stretching temperature.

Study on the method of safety diagnosis of electrical equipments using fuzzy algorithm (퍼지알고리즘을 이용한 전기전자기기의 안전진단방법에 대한 연구)

  • Lee, Jae-Cheol
    • Journal of Digital Convergence
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    • v.16 no.7
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    • pp.223-229
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    • 2018
  • Recently, the necessity of safety diagnosis of electrical devices has been increasing as the fire caused by electric devices has increased rapidly. This study is concerned with the safety diagnosis of electric equipment using intelligent Fuzzy technology. It is used as a diagnostic input for the multiple electrical safety factors such as the use current, cumulative use time, deterioration and arc characteristics inherent to the equipment. In order to extract these information in real time, a device composed of various sensor circuits, DSP signal processing, and communication circuit is implemented. The fuzzy logic algorithm using the Gaussian function for each information is designed and compiled to be implemented on a small DSP board. The fuzzy logic receives the four diagnostic information, deduces it by the fuzzy engine, and outputs the overall safety status of the device as a 100-step analog fuzzy value familiar to human sensibility. By experiments of a device that combines hardware and fuzzy algorithm implemented in this study, it is verified that it can be implemented in a small DSP board with human-friendly fuzzy value, diagnosing real-time safety conditions during operation of electric equipment. In the future, we expect to be able to study more intelligent diagnostic systems based on artificial intelligent with AI dedicated Micom.

Predictors and Frailty Level in the Frail Elderly Receiving Home Visiting Health Care Services (방문건강관리사업 대상 재가노인의 허약정도와 예측요인)

  • Park, Jeong Sook;Oh, Yun Jung
    • Journal of agricultural medicine and community health
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    • v.41 no.3
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    • pp.129-139
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    • 2016
  • Objective: The purpose of this study was to identify the predictors and frailty level in the frail elderly receiving home visiting health care services. Methods: The subjects were 177 frail elders aged over 65 registered in the home visiting health care services of three public health centers in Daegu. The data collection was performed from June 9 to June 24, 2015. This study used descriptive statistics, t-test, ANOVA, scheffe test and stepwise multiple regression by SPSS Win 18.0 program. Results: The mean of the frailty score was 10.05 (${\pm}4.52$). Age and life satisfaction were the significant factors related to the frailty score in frail elderly. Health promotion behavior, empowerment, social participation and perceived health status had a negative correlation with the frailty score. Thirty seven point four percent of the variance in the frailty score can be explained by perceived health status (${\beta}=-0.398$, p<0.001), health promotion behavior (${\beta}=-0.251$, p<0.001) and age (${\beta}=0.232$, p<0.001)(Cum $R^2=0.374$, F=25.744, p<0.001). Perceived health status was the most important factor related to the frailty score in our study. Conclusions: An integrative care program which includes these significant variables of subjects is essential to prevent the deterioration of frailty in frail elderly.

Development of Route Selecting System based on GIS for Prior Environmental Review using AHP (AHP 기법을 활용한 GIS기반의 사전환경성검토 노선선정시스템 개발)

  • Kim, Sang-Seok;Jang, Yong-Gu;Yang, Seung-Tae;Kang, In-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.2
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    • pp.152-163
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    • 2007
  • The on-going pre-environmental investigation at present is performed by separate numerical analysis of each provision which makes integrated pre-environmental investigation is difficult. The application of numerical data is insufficient, which results to the deterioration of environmental investigation result's objectivity. A lot of time and money is required for the investigation. In this study, the spacial analysis function of GIS was applied on the 8 pre-environmental investigation factors. Pre-environmental investigation GIS DMS(Decision Making System) using AHP was constructed to make integrated investigation possible through the use of investigation results for each factor. Through the use of the developed pre-environmental investigation GIS DMS and the pre-constructed GIS data, the objectivity of environmental investigation is sufficient and time and cost are reduced. Therefore, this system can be used for pre-environmental investigation during route selection in the initial stages of road construction. Through the numerical and visual data obtained from the system developed in this paper, it is easier to gain the approval of the public. Furthermore, environmental problems due to road construction can be investigated with less time and money during the initial stages of road construction.

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Electric Circuit Analysis for PV Array on Short-Circuit Failure of Bypass Diode in PV Module (PV모듈의 바이패스 다이오드 단락 고장 시 태양광어레이 회로 특성분석)

  • Lee, Chung-Geun;Shin, Woo-Gyun;Lim, Jong Rok;Hwang, Hye-Mi;Ju, Young-Chul;Jung, Young-Seok;Kang, Gi-Hwan;Chang, Hyo-Sik;Ko, Suk-Whan
    • Journal of the Korean Solar Energy Society
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    • v.39 no.6
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    • pp.15-25
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    • 2019
  • As the installation of photovoltaic systems increases, fire accidents of PV system grow every year. Most of PV system fires have been reported to be caused by electrical components. The majority of fire accidents occurred in combiner box, which is presumed to be short-circuit accidents due to dustproof and waterproof failures or heat deterioration of blocking diode. For this reason, the blocking diode installation became optional by revised PV combiner regulation. In this paper, according to the revised regulation, reverse current that generated by voltage mismatch was measured and analyzed in PV array without a blocking diode. The factors that cause voltage mismatch in array are assumed to be shaded PV module and short circuit failure of bypass diode. As the result of experiment, there is no reverse current to flow under shading condition in module, but reverse current flows on the failure of bypass diode in module. According to the module's I-V characteristic curve analysis, open voltage was slightly reduced due to operation of bypass diode in shading. However, it showed that open circuit voltage has decreased significantly in the failure of bypass diode. This indicates that the difference in open voltage reduction of voltage mismatch factor causes reverse current to flow.

Optimization and characterization of biodiesel produced from vegetable oil

  • Mustapha, Amina T.;Abdulkareem, Saka A.;Jimoh, Abdulfatai;Agbajelola, David O.;Okafor, Joseph O.
    • Advances in Energy Research
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    • v.1 no.2
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    • pp.147-163
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    • 2013
  • The world faces several issues of energy crisis and environmental deterioration due to over-dependence on single source of which is fossil fuel. Though, fuel is needed as ingredients for industrial development and growth of any country, however the fossil fuel which is a major source of energy for this purpose has always been terrifying thus the need for alternative and renewable energy sources. The search for alternative energy sources resulted into the acceptance of a biofuel as a reliable alternative energy source. This work presents the study of optimization of process of transesterification of vegetable oil to biodiesel using NaOH as catalyst. A $2^4$ factorial design method was employed to investigate the influence of ratio of oil to methanol, temperature, NaOH concentration, and transesterification time on the yield of biodiesel from vegetable oil. Low and high levels of the key factors considered were 4:1 and 6:1 mole ratio, 30 and $60^{\circ}C$ temperatures, 0.5 and 1.0 wt% catalyst concentration, and 30 and 60 min reaction time. Results obtained revealed that oil to methanol molar ratio of 6:1, tranesetrification temperature of $60^{\circ}C$, catalyst concentration of 1.0wt % and reaction time of 30 min are the best operating conditions for the optimum yield of biofuel from vegetable oil, with optimum yield of 95.8%. Results obtained on the characterizzation of the produced biodiesel indicate that the specific gravity, cloud point, flash point, sulphur content, viscosity, diesel index, centane number, acid value, free glycerine, total glycerine and total recovery are 0.8899, 4, 13, 0.0087%, 4.83, 25, 54.6. 0.228mgKOH/g, 0.018, 0.23% and 96% respectively. Results also indicate that the qualities of the biodiesel tested for are in conformity with the set standard. A model equation was developed based on the results obtained using a statistical tool. Analysis of variance (ANOVA) of data shows that mole ratio of ground nut oil to methanol and transesterification time have the most pronounced effect on the biodiesel yield with contributions of 55.06% and 9.22% respectively. It can be inferred from the results various conducted that vegetable oil locally produced from groundnut oil can be utilized as a feedstock for biodiesel production.

Emission Characteristics of Volatile Organic Compounds from Building Flooring Materials (건축용 바닥재로부터의 휘발성유기화합물 방출특성)

  • Yun, Joong-Seop;Lee, Myong-Hwa;Eom, Seok-Won;Kim, Min-Young;Kim, Jong-Ho;Kim, Shin-Do
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.10
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    • pp.973-978
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    • 2010
  • The emission of volatile organic compounds (VOCs) from building materials is one of great concerns due to maintain airtight condition of a building to reduce energy consumption, and it causes the deterioration of indoor air quality. Therefore, the emission characterization of VOCs from building materials is necessary to improve indoor air quality. Emission characteristics of VOCs from a plywood flooring that is one of the most commonly used materials in an under-heating system, and from an adhesive that is generally used to stick a plywood flooring to a concrete floor were investigated using an emission chamber test in this study. It was found that the VOCs emission factor was dependent upon and proportional to indoor temperature, and the emission characteristics were closely related to the existing places and conditions of VOCs sources inside the building materials. Maximum emission factors of hexane and toluene from building materials were generally observed at the beginning, however, only that of toluene from a plywood flooring was shown after 6 hours from the beginning. It could be considered that the existing place and condition of toluene source inside a plywood flooring could influence on the VOCs emission. From this study, bake-out time more than 72 hours could be recommended before moving in to avoid the exposure to high concentration of VOCs emitted from an under-heating system.

The MTF Measurement of the Conventional X-ray System by using the Computed Radiography (CR을 이용한 일반촬영장치의 MTF 측정)

  • Kim, Chang-Bok
    • Journal of radiological science and technology
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    • v.28 no.2
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    • pp.111-115
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    • 2005
  • The quality of image from the system that creates medical images by using X-ray depends on the various different reasons such as the X-ray generator, the subject and the image transmission medium. In other words, thereare various factors existing that can influence on the quality of image from the moment when the X-ray is generated and until the final image is created. Therefore, the operator who creates images at the clinical site should make continuous evaluation and observation from the final image. There are various methods of evaluating the medical images, but it is assumed that the MTF measurement method can be suitable for measuring actual or effective resolution. So in this study, the MTF measurement method by using X-ray film has been avoided and the MTF features according to the deterioration of the X-ray system have been measured by using the software (the program used Borland C++ builder software and LEAD tools software) that can measure the MTF of the digital medical images. As the result of this measurement, it has been found out through the MTF graph that the resolution and sharpness from the old x-ray generator with a many years of using and many numbers of times of using were deteriorated for the quality of image comparing to those from the new system. Also a simple and easy measurement method for the MTF from the digital medical images can be obtained in this study.

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An Exploration on Prescription of Resistance Training for Geriatric Physical Therapy (노인물리치료를 위한 저항트레이닝 처방에 대한 탐색)

  • Shin Hong-Cheul;Jeong Dong-Hyuk
    • The Journal of Korean Physical Therapy
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    • v.15 no.1
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    • pp.61-81
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    • 2003
  • There can be little dissension that the ultimate goal of all physical therapy interventions with the elderly is to restore or maintain the highest level of function possible for the individual. Whenever physical therapists take on this challenge, they assist elders in maintaining their identities as competent adults. Advancing age is associated with profound changes in body composition, including increased fat mass, decreased fat-free mass(particularly muscle), decreased total body water and decreased bone density. Along with these changes in body compositions, and perhaps as a direct result of them, elderly people have lower energy needs, reduced strength and functional capacity and a greatly increased risk for such diseases as noninsulin-dependent diabetes mellitus and osteoporosis. Resistance training is considered a promising intervention for reversing the loss of muscle function and the deterioration of muscle structure that is associated with advanced age. This reversal is thought to result in improvements in functional abilities and health status in the elderly by increasing muscle mass, strength and power and by increasing bone mineral density. In the past couple of decades, many studies have examined the effects of Resistance training on risk factors for age-related diseases or disabilities. We have explored the positive and negative aspects of older adults' participation in resistance training programs. The benefits to older adults are reported to be increased strength, endurance, muscle capacity, and flexibility; more energy; and improved self-image and confidence. The negative aspects include some pain or stiffness and other nonspecific problems. The positive and negative aspects of resistance training are therefore very similar to those in younger populations. Scientific investigations over the past 10 years have demonstrated that resistance training can be safely and successfully implemented in older populations. Even the frail and very sick elderly can benefit and improve their quality of life. Proper design and progression of a resistance training program for older adults is vital to optimal benefits from resistance exercise. The results of data provided by this research on resistance training for health shows that there is enough existing evidence to conclude that resistance training, particularly when incorporated into a comprehensive fitness program, can offer substantial health benefits which can be obtained by persons of all ages. These benefits, including improvements in functional capacity, translate into an improved quality of life.

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