• Title/Summary/Keyword: Limited Sound Level

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Development of the Furling Control Type Small Wind Turbine System (과풍속 출력 제한형 소형 풍력 발전장치 개발)

  • Choi, Young-Chul;Kim, Chul-Ho;Lee, Hyun-Chae;Seo, Young-Taek;Han, Young-Oun;Song, Jung-Il
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.6
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    • pp.693-701
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    • 2012
  • In this study, a small wind turbine airfoil specialized for national wind condition was designed in order to develop the furling control type HAWT. And then a flow analysis was carried out based on the blade drawing which was designed to characterize of the developed airfoil. The result of the flow analysis showed that the torque on the 3 blades was 180.23N.m. This is equivalent to an output power of 5.66kw and an output efficiency of 0.44. Then we produced and constructed a 3kW - furling control type HAWT by getting the system unit design technology such as the specialized furling control device. By operating this turbine, we could get 3kW of the rated power at a wind speed of 10.5m/s through the ability test. Cut-in wind speed was 2m/s, generator efficiency was 92% at the rated power output. Sound power level was 87.2dB(A). Also we observed that the output power was limited to 10.5m/s with furling system operation.

Pathogenic E. coli Inactivation in Upland Soils to a Change of Soil Moisture Content and Temperature (밭토양에서 토양수분과 온도변화에 따른 분변성 대장균 사멸율 변화)

  • Kim, Min-Kyeong;Kim, Min-Young;Choi, Chul-Man;Ko, Byong-Gu;Kwon, Soon-Ik;Weon, Hang-Yeon
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.1
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    • pp.90-95
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    • 2010
  • The application of livestock manure to cropland is a practice that has been used for centuries. Agricultural crops can utilize nutrients from manure, and the producer can utilize land for disposal, although in a "sustainable system" the concept is manure utilization and not waste disposal. However, meeting regulatory criteria regarding microbial quality remains an expensive and time consuming process. The purpose of this study was to quantify the level of environmental impact of soil moisture and temperature on fecal coliform (Escherichia coli or E. coli) survival in upland soils for sound application of livestock manure. Samples were collected up to 30 days depending on the given conditions. The inactivation rate of E. coli increased linearly with increased temperature while the inactivation rate gradually decreased with decreased soil moisture level. The overall findings of this study showed that the temperature was the limited factor on E. coli survival in soils over soil moisture content. This study will provide useful and practical guidelines to applicators of soil in deciding appropriate handling and time frames for land application for sustainable agriculture.

High-frequency Reverberation Simulation of High-speed Moving Source in Range-independent Ocean Environment (거리독립 해양환경에서 고속이동 음원의 고주파 잔향음 신호모의)

  • Kim, Sunhyo;Lee, Wonbyoung;You, Seung-Ki;Choi, Jee Woong;Kim, Wooshik;Park, Joung Soo;Park, Kyoung Ju
    • The Journal of the Acoustical Society of Korea
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    • v.32 no.2
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    • pp.104-115
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    • 2013
  • In a shallow water waveguide, reverberation signals and their Doppler effects form the primary limitation on sonar system performance. Therefore, in the reverberation-limited environment, it is necessary to estimate the reverberation level to be encountered under the conditions in which the sonar system is operated. In this paper, high-frequency reverberation model capable of simulating the reverberation signals received by a high-speed moving source in a range independent waveguide is suggested. In this model, eigenray information from the source to each boundary is calculated using the ray-based approach and the optimizing method for the launch angles. And the source receiving position changed by the moving source is found by a scattering path-finding algorithm, which considers the speed and direction of source and sound speed to find the path of source movement. The scattering effects from sea surface and bottom boundaries are considered by APL-UW scattering models. The model suggested in this paper is verified by a comparison to the measurements made in August 2010. Lastly, this model reflects well statistical properties of the reverberation signals.

Comparison of Meal Management Attitudes among Housewives between in Industrial Complex and in Non-Industrial Complex on Ansan City in Korea (일부 공단 지역 가정 어머니의 식생활 관리 태도 비교)

  • 남숙연;김선효
    • Journal of the Korean Home Economics Association
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    • v.40 no.4
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    • pp.167-178
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    • 2002
  • This study was carried out to compare the meal management attitudes among the mothers(41 years of age) who had middle school students between in industrial complex and in non-industrial complex. The subjects of each group were composed of 192 mothers Living in Ansan city in Korea, and this study was performed by self-administered questionnaire. The results of the present study were as follows: (1) Monthly family income and education level of parents were lower in industrial complex-family(ICF) than in non-industrial complex-family (NICF). The mean age of mothers and family size were similar in two groups, but the frequency of mothers employed was higher in ICF than in NICF Most mothers in ICF worked as a manual- or skilled-laborer. (2) The mothers in ICF tended to have less positive attitude in sewing balanced meals to their families than those in NICF. The score of nutritional knowledge was lower in mothers in ICF than those in NICF. (3) The percentage of expense for purchasing staple foods to total expense of foods tended to be higher in ICF than in NICF. Engel's coefficient was higher, and the frequency and expense for eating out was lower in ICF than in NICF (4) The mothers in ICF did not try to use their time and energy efficiently for meal management. (5) The mothers in ICF were less active in sewing the pleasurable meals including the provision of various cooking methods, flavors, and temperatures, to their families, than those in NICF. Above findings show that family environment such as industrial complex-families and non-industrial complex-families influences the meal management attitudes of mothers. The mothers in ICF had a less positive altitudes for scientific meal managements than those in NICF even though they had the limited resources including money, time and energy for meal management because most mothers in ICF had a job that were paid low salary and finished irregularly or late. Therefore, these results underscore the need to provide the sound nutritional education for the mothers in ICF with respect to reasonable meal management for 'optimal nutrition of family'. In addition, the government should try to make the various welfare policies to improve nutritional status of low income famines including the poor industrial complex-families.

Study of Pro-environmental Development for Golf Course in Korea (한국 골프장의 친환경적 개발에 관한 연구)

  • 김광두
    • Asian Journal of Turfgrass Science
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    • v.12 no.1
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    • pp.49-78
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    • 1998
  • Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

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Determining Correlation between Experiences of a Sensory Courtyard and DAS (Depression, Anxiety and Stress)

  • Nam, Jinvo;Kim, Keunho
    • Journal of People, Plants, and Environment
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    • v.24 no.4
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    • pp.403-413
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    • 2021
  • Background and objective: There is growing concern about the effects of modern society on mental health, coming with Covid-19-related caveats on depression, anxiety, and stress (DAS). This can be a subject to provide alternative methods which alleviate DAS. In line with this context, sensory gardens are widely acknowledged to stimulate the five major senses (sight, sound, taste, touch, and smell) and can have a significant (positive) impact on mental health. However, there is limited empirical evidence on the effect of these gardens with regard to alleviating DAS - particularly with respect to urban society This is a gab in knowledge how such limits can be addressed. Accordingly, this present study is clearly needed in order to verify if there are any correlations between sensory gardens and (positive) effects on DAS. The aim of this study was therefore to understand current levels of DAS in a high density building with a sensory garden in a courtyard and determine correlations between experiences in the sensory courtyard and levels of DAS. Methods: The Depression Anxiety and Stress Scale (DASS-21) was employed to test the level of DAS. Results: Additionally, 13 different factors associated with experiences in the building, including the stimulation of the five major senses in the sensory courtyard, were measured to reveal their contribution to mitigating depression, anxiety, and stress. It is noted that the average levels of DAS were 7.91, 7.77 and 9.01 respectively indicating that the mental health of participants requires mental health management. However, results show that factors associated with the sensory courtyard could improve mental health. For example, new social relationships, walking with colleagues, and the stimulation of each of the five major senses in the sensory garden could improve DAS. Conclusion: This illustrates that external experiences are more effective at mitigating depression, anxiety, and stress than internal ones. Factor analysis revealed four components: stimulating the five senses; internal and external facilities; internet-based device use; and new social relationships. There was a strong positive correlation between new social relationships and walking with colleagues. There were also strong positive correlations among the stimulation of each of the five senses. In conclusion, there are strong indications that sensory courtyards can help alleviate DAS and should therefore be promoted, particularly in the current Covid-19 situation wherein the physical and mental health of the public at large are threatened. Accordingly, courtyard design should be rethought in light of the relationship between the positive impact of sensory gardens and mental health.

A Study on the Risk Factors for Maternal and Child Health Care Program with Emphasis on Developing the Risk Score System (모자건강관리를 위한 위험요인별 감별평점분류기준 개발에 관한 연구)

  • 이광옥
    • Journal of Korean Academy of Nursing
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    • v.13 no.1
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    • pp.7-21
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    • 1983
  • For the flexible and rational distribution of limited existing health resources based on measurements of individual risk, the socalled Risk Approach is being proposed by the World Health Organization as a managerial tool in maternal and child health care program. This approach, in principle, puts us under the necessity of developing a technique by which we will be able to measure the degree of risk or to discriminate the future outcomes of pregnancy on the basis of prior information obtainable at prenatal care delivery settings. Numerous recent studies have focussed on the identification of relevant risk factors as the Prior infer mation and on defining the adverse outcomes of pregnancy to be dicriminated, and also have tried on how to develope scoring system of risk factors for the quantitative assessment of the factors as the determinant of pregnancy outcomes. Once the scoring system is established the technique of classifying the patients into with normal and with adverse outcomes will be easily de veloped. The scoring system should be developed to meet the following four basic requirements. 1) Easy to construct 2) Easy to use 3) To be theoretically sound 4) To be valid In searching for a feasible methodology which will meet these requirements, the author has attempted to apply the“Likelihood Method”, one of the well known principles in statistical analysis, to develop such scoring system according to the process as follows. Step 1. Classify the patients into four groups: Group $A_1$: With adverse outcomes on fetal (neonatal) side only. Group $A_2$: With adverse outcomes on maternal side only. Group $A_3$: With adverse outcome on both maternal and fetal (neonatal) sides. Group B: With normal outcomes. Step 2. Construct the marginal tabulation on the distribution of risk factors for each group. Step 3. For the calculation of risk score, take logarithmic transformation of relative proport-ions of the distribution and round them off to integers. Step 4. Test the validity of the score chart. h total of 2, 282 maternity records registered during the period of January 1, 1982-December 31, 1982 at Ewha Womans University Hospital were used for this study and the“Questionnaire for Maternity Record for Prenatal and Intrapartum High Risk Screening”developed by the Korean Institute for Population and Health was used to rearrange the information on the records into an easy analytic form. The findings of the study are summarized as follows. 1) The risk score chart constructed on the basis of“Likelihood Method”ispresented in Table 4 in the main text. 2) From the analysis of the risk score chart it was observed that a total of 24 risk factors could be identified as having significant predicting power for the discrimination of pregnancy outcomes into four groups as defined above. They are: (1) age (2) marital status (3) age at first pregnancy (4) medical insurance (5) number of pregnancies (6) history of Cesarean sections (7). number of living child (8) history of premature infants (9) history of over weighted new born (10) history of congenital anomalies (11) history of multiple pregnancies (12) history of abnormal presentation (13) history of obstetric abnormalities (14) past illness (15) hemoglobin level (16) blood pressure (17) heart status (18) general appearance (19) edema status (20) result of abdominal examination (21) cervix status (22) pelvis status (23) chief complaints (24) Reasons for examination 3) The validity of the score chart turned out to be as follows: a) Sensitivity: Group $A_1$: 0.75 Group $A_2$: 0.78 Group $A_3$: 0.92 All combined : 0.85 b) Specificity : 0.68 4) The diagnosabilities of the“score chart”for a set of hypothetical prevalence of adverse outcomes were calculated as follows (the sensitivity“for all combined”was used). Hypothetidal Prevalence : 5% 10% 20% 30% 40% 50% 60% Diagnosability : 12% 23% 40% 53% 64% 75% 80%.

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A Comparative Study on Buddhist Painting, MokWooDo (牧牛圖: PA Comparative Study on Buddhist Painting, MokWooDo (牧牛圖: Painting of Bull Keeping) and Confucian/Taoist Painting, SipMaDo (十馬圖: Painting of Ten Horses) - Focused on SimBeop (心法: Mind Control Rule) of the Three Schools: Confucianism, Buddhism and Taoism -nd Control Rule) of the Three Schools: Confucianism, Buddhism and Taoism - (불가(佛家) 목우도(牧牛圖)와 유·도(儒·道) 십마도(十馬圖) 비교 연구 - 유불도(儒佛道) 삼가(三家)의 심법(心法)을 중심으로 -)

  • Park, So-Hyun;Lee, Jung-Han
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.4
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    • pp.67-80
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    • 2022
  • SipWooDo (十牛圖: Painting of Ten Bulls), a Buddhist painting, is a kind of Zen Sect Buddhism painting, which is shown as a mural in many of main halls of Korean Buddhist temples. MokWooDo has been painted since Song Dynasty of China. It paints a cow, a metaphor of mind and a shepherd boy who controls the cow. It comes also with many other types of works such as poetry called GyeSong, HwaWoonSi and etc. That is, it appeared as a pan-cultural phenomenon beyond ideology and nation not limited to Chinese Buddhist ideology of an era. This study, therefore, selects MokWooDo chants that represent Confucianism, Buddhism and Taoism to compare the writing purposes, mind discipline methods and ultimate goals of such chant literatures in order to integrate and comprehend the ideologies of such three schools in the ideologically cultural aspect, which was not fully dealt with in the existing studies. In particular, the study results are: First, the SipWooDo of Buddhist School is classified generally into Bo Myoung's MokWooDo and Kwak Ahm's SimWooDo (尋牛圖: Painting of Searching out a Bull). Zen Sect Buddhism goes toward nirvana through enlightenment. Both MokWooDo and SimWooDo of Buddhist School are the discipline method of JeomSu (漸修: Discipline by Steps). They were made for SuSimJeungDo (修心證道: Enlightenment of Truth by Mind Discipline), which appears different in HwaJe (畫題: Titles on Painting) and GyeSong (偈頌: Poetry Type of Buddhist Chant) between Zen Sect Buddhism and Doctrine Study Based Buddhism, which are different from each other in viewpoints. Second, Bo Myoung's MokWooDo introduces the discipline processes from MiMok (未牧: Before Tamed) to JinGongMyoYu (眞空妙有: True Vacancy is not Separately Existing) of SsangMin (雙泯: the Level where Only Core Image Appears with Every Other Thing Faded out) that lie on the method called BangHalGiYong (棒喝機用: a Way of Using Rod to Scold). On the other side, however, it puts its ultimate goal onto the way to overcome even such core image of SsangMin. Third, Kwak Ahm's SimWooDo shows the discipline processes of JeomSu from SimWoo (尋牛: Searching out a Bull) to IpJeonSuSu (入鄽垂手: Entering into a Place to Exhibit Tools). That is, it puts its ultimate goal onto HwaGwangDongJin (和光同塵: Harmonized with Others not Showing your own Wisdom) where you are going together with ordinary people by going up to the level of 'SangGuBori (上求菩提: Discipline to Go Up to Gain Truth) and HaHwaJungSaeng (下化衆生: Discipline to Go Down to Be with Ordinary People)' through SaGyoIpSeon (捨敎入禪: Entering into Zen Sect Buddhism after Completing a Certain Volume of Doctrine Study), which are working for leading the ordinary people of all to finding out their Buddhist Nature. Fourth, Shimiz Shunryu (清水春流)'s painting YuGaSipMaDo (儒家十馬圖: Painting of Ten Horses of Confucian School) borrowed Bo Myoung's MokWooDo. That is, it borrowed the terms and pictures of Buddhist School. However, it features 'WonBulIpYu (援佛入儒: Enlightenment of Buddhist Nature by Confucianism)', which is based on the process of becoming a greatly wise person through Confucian study to go back to the original good nature. From here, it puts its goal onto becoming a greatly wise person, GunJa who is completely harmonized with truth, through the study of HamYang (涵養: Mind Discipline by Widening Learning and Intelligence) that controls outside mind to make the mind peaceful. Its ultimate goal is in accord with "SangCheonJiJae, MuSeongMuChee (上天之載, 無聲無臭: Heaven Exists in the Sky Upward; It is Difficult to Get the Truth of Nature, which has neither sound nor smell)' words from Zhōngyōng. Fifth, WonMyeongNhoYin (圓明老人)'s painting SangSeungSuJinSamYo (上乘修真三要: Painting of Three Essential Things to Discipline toward Truth) borrowed Bo Myoung's MokWooDo while it consists of totally 13 sheets of picture to preach the painter's will and preference. That is, it features 'WonBulIpDo (援佛入道: Following Buddha to Enter into Truth)' to preach the painter's doctrine of Taoism by borrowing the pictures and poetry type chants of Buddhist School. Taoism aims to become a miraculously powerful Taoist hermit who never dies by Taoist healthcare methods. Therefore, Taoists take the mind discipline called BanHwanSimSeong (返還心性: Returning Back to Original Mind Nature), which makes Taoists go ultimately toward JaGeumSeon (紫金仙) that is the original origin by changing into a saint body that is newly conceived with the vital force of TaeGeuk abandoning the existing mind and body fully. This is a unique feature of Taoism, which puts its ultimate goal onto the way of BeopShinCheongJeong (法身淸淨: Pure and Clean Nature of Buddha) that is in accord with JiDoHoiHong (至道恢弘: Getting to Wide and Big Truth).