• Title/Summary/Keyword: Transmission period

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The Immune Response and Protective Efficacy of Hepatitis B Vaccine in Neonates Born from Hepatitis B Carrier Mothers (B형 간염 바이러스 보유 산모로부터 분만된 신생아의 B형 간염 백신의 면역반응 및 방어효과)

  • Kim, Jong-Hyun;Kang, Jin-Han;Hur, Jae-Kyun;Koh, Dae-Kyun;Oh, Chang-Kyu
    • Pediatric Infection and Vaccine
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    • v.5 no.1
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    • pp.96-103
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    • 1998
  • Purpose : We performed this study to evaluate the immune responses and protective efficacies of the HBV vaccine in infants born from hepatitis B virus(HBV) carrier mothers. Methods : Seventy eight infants born from HBV carrier mothers, who were able to follow up for 12months in the Catholic University St. Vincents hospital, were involved in this study from July 1995 to December 1996. Samples were collected at birth, 4, 8 and 12months after injection of HBIG and HBV heat-inactivated plasma derived vaccines. We evaluated the changes and relationships of viral markers detecting by enzyme immunoassay and radioimmunoassay between HBV carrier mothers and their infants. Results : 1) A total of 5.0%(106/2,117) of pregnant women were found to be a HBV carrier. The rates of HBeAg positive and negative were 38.5%(37/96) and 61.5%(59/96), respectively. 2) The seroconversion rates of anti-HBs with infants of HBV carrier mothers at 4, 8 and 12 months were 85.9%(67/78), 75.6%(59/78) and 73.1%(57/78), respectively. Although these were statistically significant differences(P<0.05), they were not related to HBeAg status of the mothers. The geometric mean titers of anti-HBs at 8 and 12 months were significantly higher than at 4 months, statistically(P<0.05). The protective efficacy of the HBV vaccine and HBIG at 12 months in infants from HBeAg positive and negative mothers were 89.8% and 100%, respectively. 3) Five of 78(6.4%) infants became infected by HBV from only HBeAg positive mothers during the follow up period of 12 months. Three of 5 infected infants became HBV carriers. HBsAg positive at birth from HBeAg positive and negative mother were 4 infants, respectively. Three of 4 infants became infected by HBV from only HBeAg positive mothers. Conclusion : We confirmed that the seroconversion rate of HBV heat-inactivated plasma derived vaccine which was one of other vaccines manufacturing in Korea was 85.9%. The protective efficacy of this HBV vaccine and HBIG at 12 months in infants from HBeAg positive and negative mothers were 89.8% and 100%, respectively.

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The Effects of Maternal HBs antigenemia on the Neonatal Health (산모(産母)의 B형 간염(肝炎) Virus 보유(保有)가 신생아(新生兒) 건강(健康)에 미치는 영향(影響))

  • Park, Jung-Han;Yoon, Sung-Do;Kim, Chang-Youn;Lee, Sung-Kwan
    • Journal of Preventive Medicine and Public Health
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    • v.17 no.1
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    • pp.47-55
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    • 1984
  • To study the risk factors associated with maternal HBsAg carrier and the effects of maternal HBs antigenemia on the neonatal health, sera of 729 pergnant women admitted to the Keimyung University Hospital for delivery during the period of February 1-May 30. 1982 were tested for HBsAg by RPHA method and for anti-HBs by PHA method. Among them 43 women (5.9%) had HBsAg and 246 women (33.7%) had anti-HBs giving an infection rate of 39.6%. The interview data for 43 HBsAg positive mothers and randomly selected 210 HBsAg negative mothers showed a statistically significant association between acupuncture history and HBsAg positive rate (p<0.005) which suggest that acupuncture might have contributed significantly to the propagation of viral hepatitis in Korea. The living standard of HBsAg positive mothers was generally lower than that of HBsAg negative mothers which supports the hypothesis that environmental factors are associated with viral hepatitis B infection. None of the 43 neonates born to HBsAg positive mothers had HBsAg in their cord blood. Three months after birth, 35 out of 43 infants were retested and only one infant became HBsAg positive. At six months of age, 32 out of 35 infants were retested and none of them were HBsAg positive except the same infant who was positive at three months. Among 20 control infants of HBsAg negative mothers, all of them were HBsAg negative at three and six months follow-up. These findings are not consistent with the supposition that perinatal infection is a main route of viral hepatitis B transmission in south-east Asia including Korea. HBsAg positive mothers had significantly higher rate of premature delivery (27.9%) than HBsAg negative mothers (11.7%) (p<0.05). Also, the low birthweight incidence rate was higher among HBsAg positive mothers (23.3%) than negative mothers (14.1%) but this was not statistically significant (P=0.16). The premature rupture of membrane was more frequent among HBsAg positive mothers (25.5%) than negative mothers (11.1%) (p<0.05). There were no significant differences in the stillbirth rate and incidence of congenital anomalies between HBsAg positive and negative groups. It was not clarified in this study due to small sample size whether higher incidence of premature delivery and premature rupture of membranes among HBsAg positive mothers was due to HBs antigenemia per so or their lower living standard than HBsAg negative mothers.

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Intensive Culture of the Pacific White Shrimp Litopenaeus vannamei, under Limited Water Exchange - II. Indoor Post-Nursery Culture of Juvenile Shrimp - (사육수 비교환 방식에 의한 흰다리새우의 고밀도 사육 - II. 흰다리새우의 실내 중간양성 -)

  • Jang, In-Kwon;Kim, Jong-Sheek;Seo, Hyung-Chul;Cho, Kook-Jin
    • Journal of Aquaculture
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    • v.22 no.1
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    • pp.42-50
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    • 2009
  • Shrimp farming which is entirely conducted in outdoor ponds in the west coast of Korea has been suffered from mass mortality due to viral epizootics. Intensive indoor shrimp culture under limited water exchange can solve these problems of outdoor ponds including viral transmission from environment, pollution due to discharge of rearing water, low productivity and limited culture period. In this study, juvenile L. vannamei (B.W. 0.08-0.09 g) was stocked with $3,000-5,455/m^3$ in density in four raceway tanks (two $12.9\;m^2$, two $18\;m^2$ tanks) and cultured for 42 days with 2.7-3.4% of daily water exchange. Results from four tanks showed FCR of 0.79-1.29, survival of 38.2-48.0%, and yields of $2.49-4.22\;kg/m^3$ which is consistent with 12-20 and 8-14 times higher than those of commercial shrimp hatchery and outdoor pond in Korea, respectively. Concentrations of total ammonia nitrogen in all four tanks were 1.11-1.42 ppm in mean level and did not exceed 6.0 ppm (0.096 ppm of $NH_3$) which is still acceptable levels for shrimp growth. During the culture trial, concentration of $NO_2$-N rapidly increased from stocking, resulting in mean concentration of 18.45-22.07 ppm. It also exceeded 10 ppm over four weeks and maintained at 35-45 ppm for four days in all tanks, accounting for low survival of shrimp due to long-term exposure to high concentration of $NO_2$-N. Nevertheless, the results with survival rate over 38% from raceways which experienced the extreme $NO_2$-N levels suggests that under "biofloc system" white shrimp can acclimate to high $NO_2$-N concentration to some degree.

Various Cultural Factors Associated with Disease Development of Garlic White Rot Caused by Two Species of Sclerotium (마늘 흑색썩음균핵병 발생에 관여하는 여러가지 경종적 요인)

  • Kim, Yong-Ki;Kwon, Mi-Kyung;Shim, Hong-Sik;Kim, Tack-Soo;Yeh, Wan-Hae;Cho, Weon-Dae;Choi, In-Hu;Lee, Seong-Chan;Ko, Sug-Ju;Lee, Yong-Hwan;Lee, Chan-Jung
    • Research in Plant Disease
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    • v.11 no.1
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    • pp.28-34
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    • 2005
  • This study was conducted to investigate the control possibility of garlic white rot causing severe yield losses of Allium species and cultivars using cultural practices such as optimal sowing date and burial depth, and lime application. Inoculum density in infested field soil was investigated at different soil depth, and that on the diseased plant debris was done. Inoculum density and recovery ratio of white rot pathogen of garlic was highly different between two species of Sclerotium cepivorum forming comparatively small sclerotia and Sclerotium sp. forming comparatively large ones. It was confirmed that S. cepivorum formed more sclerotia on bulbs of garlic than S. sp., and sclerotial recovery of S. cepivorum was higher than that of S. sp. Inoculum density of white rot pathogen in the infested field at garlic seeding period ranged from one to thirteen sclerotia per 30 g soil. Inoculum density of white rot pathogen decreased remarkably with increasing soil depth and above 95% of sclerotia were distributed within 5 cm of soil depth. Disease severity of white rot was higher on slightly planted garlics than deeply-planted ones. Garlic seed bulbs infected by white rot pathogens were confirmed to be one of main inoculum sources of white rot in the field and the disease incidences caused by garlic seed transmission showed big differences among garlic varieties. When nine garlic varieties harvested from infested plots were sown in the field, highly susceptible varieties, ‘Wando’, ‘Daeseo’, ‘Namdo’ and ‘Kodang’ showed high disease incidences, whereas other five varieties were not infected at all. It was confirmed that white rot occurred higher on early-sown garlics, before middle October, than on late-sown ones, after late October. Meanwhile, increasing application rate of lime ranged from 100 to 300 g reduced disease severity of white rot.

Effects of Chlorine Water and Plasma Gas Treatments on the Quality and Microbial Control of Latuca indica L. Baby Leaf Vegetable during MA Storage (염소수와 플라즈마 가스 처리가 왕고들빼기 어린잎채소의 MA저장 중 품질과 미생물 제어에 미치는 영향)

  • Kim, Ju Young;Han, Su Jeong;Whang, Lixia;Lee, Joo Hwan;Choi, In-Lee;Kang, Ho-Min
    • Journal of Bio-Environment Control
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    • v.28 no.3
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    • pp.197-203
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    • 2019
  • This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

A Study of the Transmission of Community Religion in Seoul Focussing on the Shrine of the Authorities and the Change (서울지역 공동체신앙 전승과정 고찰 조선시대 각사(各司) 신당(神堂)의 존재양상과 변화를 중심으로)

  • O, Mun Seon
    • Korean Journal of Heritage: History & Science
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    • v.41 no.2
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    • pp.5-25
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    • 2008
  • Seoul's community beliefs originated from the ritual performed by the shrines affiliated to each government office in the Joseon Dynasty. Lower branches of government officials were assigned to perform these rituals. Generally, these shrines were called Bugundang(府君堂). Records show that Bugundang(府君堂) was generally one to three units and enshrined the portrait of Bugun(府君), the worshipped, inside. According to historical records, the worshipped were mostly General Choi Young(崔瑩將軍) or Madame Song(宋氏夫人). In fact, however, each Bugundang(府君堂) worshipped different persons. Some of the worshipped were historical characters from the Goryeo Dynasty or the founding period of Joseon Dynasty, Guan Yu(關羽) and Zhuge Liang(諸葛孔明) that became gods after the Japanese Invasion of 1952, Wanggun(王建), Dangun(檀君), General Nam Yi(南怡將軍), Kim Yoo Shin(金庾信), Lim Gyeong Up (林慶業), King Gongmin(恭愍王), King Taejo(Lee Sung Gye, 太祖 李成桂), Joban(趙?) who is one of the supporters of the foundation of Joseon Dynasty, Sir Hong(洪氏大監) and his women who appear in the legend of Nanhansanseong(南漢山城) area, and many other historical figures. It is difficult to compare the rituals of these shrines from community Gut(Shaman ritual) performances of Seoul. According to historical records, Gut and ceremony coexisted in rituals. As time passed, these rituals spread as the community Beliefs of commoners and have been transmitted in the context of Seoul's cultural change. This study examined the existence of affiliated shrines of local government offices in the Joseon Dynasty and discussed the cases of Jangchung-dong Gwanseong Shrine(將忠洞 關聖廟), Bangsan-dong Seongje Shrine(方山洞 聖帝廟), and Seobinggo Bugundang(西氷庫 府君堂) to trace the succession of rituals at these shrines as folk customs of commoners. Bangsan-dong Seongje Shrine(方山洞 聖帝廟) spread to the public as Gwanwoo(關羽), who was considered the god of soldiers, transformed into the god of merchants along with historical transition. It clearly shows the process as to how merchants from a certain region developed a community religion. Jangchung-dong Gwanseong Shrine(將忠洞 關聖廟) is Bugundang(府君堂) of the soldiers of Nampyoug(南營). As the ritual was succeeded by a ritual group called Yeoungsinsa(永信社), composed of nearby residents, it was naturally spread and succeeded by the residents in local community. Seobinggo Bugundang(西氷庫 府君堂) was related to the changes in the historical background of ice gathering in the late Joseon Dynasty.

A Study on tradition of Nihonbuyo(日本舞踊) and the Imoto(家元) system (니혼부요(日本舞踊)의 전승과 이에모토(家元) 제도)

  • Nam, Sung-Ho
    • (The) Research of the performance art and culture
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    • no.40
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    • pp.71-109
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    • 2020
  • Nihonbuyo(日本舞踊), a typical traditional Japanese dance, began with kabuki dancing and formed many schools, and was managed by Iemoto system. Iemoto(家元) is the head family of a school of a traditional Japanese art. Iemoto(家元) existed after the establishment of the ancient family system, and it was established as a system during the modern feudal period. Especially in Nihon Buyo, the Iemoto system has developed greatly since the modern era. Iemoto System has has contributed greatly to the succession of traditional arts and has been considered one of the characteristics of Japanese society. Basically, Iemoto system considers it the best authority to pass on the skills of excellent teachers without any distortion. It has various forms depending on the field and the school, but it is an organization with a family structure similar to that of a family with Iemoto at the top. In this article, I examined the establishment and background of the Nihonbuyo and considered the succession of the fame and authority of Iemoto through the system of succession. There are so many schools in the Nihonbuyo world that it is said to be a school kingdom. These schools were divided into kabuki actors, choreographers, female entertainers, ChiutaMai dance(地唄舞) and new dance styles, and the aspect of the Iemoto system was examined through the background and characteristics of each school. While Iemoto system has a positive aspect of inheriting the tradition, there are also many negative criticisms in the art world, such as rigid organizational management, the products of feudal society, the power of Iemoto, and the stalemate of arts. Nevertheless, in a Japanese society that places importance on tradition, the landlady system will not disappear easily. In fact, today, when there are many different art genres in common, young dancers are starting to challenge themselves along with self-examination of Iemoto in order to make the best use of traditional art. We hope that through consideration of the Japanese housekeeping system, it will become a place where intangible cultural properties will be re-acknowledged.

The Transmission Activities and characteristic of the Naeseo Traditional Folk art Conservation Association in Masan (마산 내서전통민속문화예술보존회의 전승 활동과 특징)

  • Choi, Ja-Un
    • (The) Research of the performance art and culture
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    • no.43
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    • pp.121-143
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    • 2021
  • The Aim of the this paper is to figure out impetus of the Naeseo Traditional Folk art Conservation Association. This Preservation Society derived from Hogaeri farmers' band. Through aging and hollowing out Hogaeri farmers' band got into a period of stagnation. In order to overcome slump villager and people of a township organized a conservation society in 1994. Members restored and directed folk song which from age to age for performance. are designated as cultural asset in 2017. Sutguldeong song is only song in inland area. This song are worthy of notice in . which is consist of various agricultural work songs experienced two changes. Rice-planting songs are characteristic. Especially, Executive playing a central role harden foundation of the Preservation Society. The mainspring of activity is the sense of responsibility. Preservation Society laying emphasis on recruiting new members. Preservation Society is planning to develop curriculum for Jurisdiction elementary and middle school students. This Preservation Society is made up of First generation members and Second generation members. First generation members who are born and bred in Hogaeri have been good friends both in joy and in sorrow Early days of Preservation Society. So, They has a strong family bond. In order to induce membership Members are practicing Nongak, popular folk songs, dancing program. Second generation members are not conversant with a folk song. Nonetheless They have a strong mind on a member line.

An Investigation on the self-consciousness Symptoms of the Clerical Workers attendant upon Office Automation (사무 자동화에 따른 사무직 근로자의 건강과 연관된 자각 증상에 대한 조사연구)

  • Jung, Mi Wha
    • Korean Journal of Occupational Health Nursing
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    • v.3
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    • pp.54-70
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    • 1993
  • According as the automation of clerical work(OA ; Office Automation) develops, the use of VDT(Visual or Video Display Terminal) is increasing suddenly. But, in proportion to the spread of office automation(OA tendency), the self-conciousness syptom attendant upon the work is appearing also (Kim, Jung Tae, Lee, Young Ook, 1990). The apparatuses of office enable the clerical workers to be convenient and perform mass businesses. But, they are increasing the opportunity to be exposed to VDT syndrom, techno stress, computer terminal disease, pain by muscle strain(RSI), bradycausia of noise nature, and electromagnetic waves, etc. which are referred to as the new type of occupational diseases to the workers. It is the real situation that the workers to use VDT is complaining of the physical inconvenience sense in the recent newspaper and literature, it is the point of time that the sydrome to come from VDT use and computer terminal disease, etc. must be classified into the occupational disease(Lee, Kwang Young 1990, Lee, Kyoo Hak 1990, Lee, Won Ho 1991, Lee, Si Young 1991, Lee, Joon 1991, Choi, Young Tae 1991, Heo, Seung Ho 1989). In addition, it is the real situation that the scientifitic study result about the scope that electromagnetic waves has influence on the human body has not been suggested yet, and criticism on the stable exposure permission standard about electromagnetic waves to be emitted from VDT and on the problem in the health about electromagnetic waves is continuing. (IEEE Spectrum, 1990). In addition according to the experience of nursery business of industry field, it is the real situation that the patients who consult complaining of physical and mental inconvenience sence, among the users of apparatus of office automation, are reaching 10% of the patients coming to doctor's room. Therefore, it is necessary to confirm the self-consciousness symptom that the clerical workers complain of multilaterally with the actual state examination about the use of the apparatuses of offices automaton. Thus, this study was tried as th basic data for the cosultation and education for the maintenance and furtherance of the health of workers as the nurse of industry field, by confirming the contents of self-consciousness symptom attendant upon the use of the apparatus for office outomation making the financial institution in which the spparatus for office automation in most frequently used as the subject, and by examining whether there is the difference according to the subject of study, the data were collected, by using the questionnaire method, making 200 workers who consented to the study participation as the subject, among the persons who have spent over 3 months since they used the apparatuses for office automation and didn't receive the treatment in hospital due to the clerical disease for recent 3 years. The period of data collection was from Oct. 9, 1991 to Oct. 12. As for the measurement instrument about the complaint if self-consciousness symptom attendant upon the use of apparatuses fo office automation, the question item on the complaint symptom of health problem attendant upon the treatment of VDT that Kim(1991) developed and on CMI health problem and the question items on the fatigue degree due to industry were used by previous examination to 25 persons. Collected data were analyzed with the statistical method such as percentage, arithmetic mean, Person correlation coeffient, Kai square verfication, t-test, ANOVA, etc. by using SPSS/PC+ program, and the result is as follows : 1. The self-consciousness symptom that the clerical workers complained of most frequetly appeared high in 'My eyes are tired'(99.4%), 'I feel fatigue and weariness'(99.4%), 'I feel that my head is heavy5(90.0%), 'eyesight fell'(88.8%), 'I have a stiff neck'(88.8%), 'I fell pain in the shoulder'(85.0%), 'I feel cold and painful in the eyes'(76.9%), 'I feel the dry sense of eyeball'(76.2%), 'My nerves are edgy, and I an fretful, (75.6%), 'I feel pain in the waist'(73.2%) and 'I fell pain in the back'(72.8%). It emerged that the subject use the apparatuses for office automation complained of self-consciousness symptoms related to visual symptoms and musculoskeletal symptoms. 2. As for the general feature of examination subjects, the result to see the distribution by classifying into sex, age, school career, use career of apparatuses for office automation, skillfulness degree of the use of apparatus for office automation, use hours of the apparatuses for office automation per 1 day, type of business of the apparatus for office automation, rest hours during the use of apparatus for office automation, satifaction degree of business of office automation, and work circumstance, etc. emerged as follows : As for the sex of subjects, the distribution showed that men were 58.8% and women were 41.3%, Age was average 26.9. As the distribution of school career, the distribution showed that4below the graduation of high school' was 58.8%, 'graduation from junior college-university' was 35.0%, and 'over graduate school' was 6.3%. In the question to ask the existence or non-existence of experience of health consultation in connection with the work of office automation, the response that I had the consultation exprience and I feel the necessity emergerd as 90.1% And, the case that the subject who didn't wear the glasses or lens before using the OA apparatus wear glasses or lens after using OA apparatus emerged as 28.3% of whole. As for the existence or non-existence of use career of OA apparatus, the case under 3 years was highest as 52. 7%. As for the skillfulnness degree about the use of apparatus for office automation, most of them are skillful with the fact that 'common' was 44.4%, 'skill' was 42.5%, and 'unskillful' was 13.1% As for the use average hours of the apparatus for office automation per 1 day, the distribution showed that the case under 3-6 hours was 33.1%, the case under 6-9 hours was 28.1%, the case under 3 hours was 30.6%, and the case over 9 hours was 8.1% Main OA business and the use hours for 1 day showed in the order of keeping and retrieval, business of information transmission(162min), business of information transmission(79.3 min), business of document framing(55.5 min), and business of duplication and printing(25.4min). as for the rest during the use of apparatus for affice automation, that I take rest occasion demands the major portion, but that I take after completing the work emerged as 33.8%. Though the subiness gets to be convenient by the use of the apparatus for of office automation, respondents who showed the dissatisfaction about the present OA business emergd high as 78.1%. The work circumstances of each office was good with the fact that the temperature of office was 21.8, noise was average 42.7db, and the illumination was average 364.4 lx, in the light of ANSi/HFS 100 Standard. 3. Sight syptom, musculoskeletal symptom, skin and other symptoms showed the significant difference according to the extent of skillfulness of the apparatus for office automation. All the symptoms exept skin symptom showed the difference according to the use hours of the apparatus for office automation. All the question items exept the sytoms of digestive organs and the rest hours during the apparatus for office automation showed the signicant difference. The question item which showed the signicant difference from the satisfaction degree of present OA business showed the significant difference from all the question item classified into 6 groups. But, age and school career didn't significant difference from the complaint of any self-consciousness symptoms.

    . In conclusion, the self-consciousness symptoms of the subjects to use OA apparatus appeared differently, according to sex distiction, skillfull degree of OA apparatus, use hours of OA apparatus, the rest hours during th use of OA apparatus, and the satiafaction degree of persent business. Therefore, it is necessary that the nurse in the inuctry field must recognize to receive the education about the human technological physical condition which is most proper for te use of OA apparatus and about the proper rest method until they get accustomed to the use of OA apparatus. In addition, the simple exercise relax the tention of muscle due to the repetitive simple movement, and the education for the protection of eyesight are necessary.

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  • On the vibration influence to the running power plant facilities when the foundation excavated of the cautious blasting works. (노천굴착에서 발파진동의 크기를 감량 시키기 위한 정밀파실험식)

    • Huh Ginn
      • Explosives and Blasting
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      • v.9 no.1
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      • pp.3-13
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      • 1991
    • The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ${\phi}70mm$ on the calcalious sand stone (soft -modelate -semi hard Rock). The total numbers of test blast were 88. Scale distance were induced 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ were V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum charge per delay-period of eight milliseconds or more (kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents where the quantity $\frac{D}{W^b}$ is known as the scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagorized in three groups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge Per delay Plots of peak particle velocity versus distoance were made on log-log coordinates. The data are grouped by test and P.P.V. The linear grouping of the data permits their representation by an equation of the form ; $V=K(\frac{D}{W^{\frac{1}{3}})^{-n}$ The value of K(41 or 124) and n(1.41 or 1.66) were determined for each set of data by the method of least squores. Statistical tests showed that a common slope, n, could be used for all data of a given components. Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m ------- under l00m ${\cdots\cdots\cdots}{\;}41(D/sqrt[2]{W})^{-1.41}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}A$ Over 100m ${\cdots\cdots\cdots\cdots\cdots}{\;}121(D/sqrt[3]{W})^{-1.66}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}B$ where ; V is peak particle velocity In cm / sec D is distance in m and W, maximLlm charge weight per day in kg K value on the above equation has to be more specified for further understaring about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

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