• Title/Summary/Keyword: methods of data analysis

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Optimal supervised LSA method using selective feature dimension reduction (선택적 자질 차원 축소를 이용한 최적의 지도적 LSA 방법)

  • Kim, Jung-Ho;Kim, Myung-Kyu;Cha, Myung-Hoon;In, Joo-Ho;Chae, Soo-Hoan
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.47-60
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    • 2010
  • Most of the researches about classification usually have used kNN(k-Nearest Neighbor), SVM(Support Vector Machine), which are known as learn-based model, and Bayesian classifier, NNA(Neural Network Algorithm), which are known as statistics-based methods. However, there are some limitations of space and time when classifying so many web pages in recent internet. Moreover, most studies of classification are using uni-gram feature representation which is not good to represent real meaning of words. In case of Korean web page classification, there are some problems because of korean words property that the words have multiple meanings(polysemy). For these reasons, LSA(Latent Semantic Analysis) is proposed to classify well in these environment(large data set and words' polysemy). LSA uses SVD(Singular Value Decomposition) which decomposes the original term-document matrix to three different matrices and reduces their dimension. From this SVD's work, it is possible to create new low-level semantic space for representing vectors, which can make classification efficient and analyze latent meaning of words or document(or web pages). Although LSA is good at classification, it has some drawbacks in classification. As SVD reduces dimensions of matrix and creates new semantic space, it doesn't consider which dimensions discriminate vectors well but it does consider which dimensions represent vectors well. It is a reason why LSA doesn't improve performance of classification as expectation. In this paper, we propose new LSA which selects optimal dimensions to discriminate and represent vectors well as minimizing drawbacks and improving performance. This method that we propose shows better and more stable performance than other LSAs' in low-dimension space. In addition, we derive more improvement in classification as creating and selecting features by reducing stopwords and weighting specific values to them statistically.

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Concurrent Chemoradiotherapy in Locally Advanced Esophageal Cancer (국소적으로 진행된 식도암에서 동시항암화학방사선치료의 결과)

  • Byun, Sang-Jun;Kim, Jin-Hee;Kim, Ok-Bae;Song, Hong-Suk
    • Radiation Oncology Journal
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    • v.29 no.1
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    • pp.20-27
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    • 2011
  • Purpose: This study was designed to evaluate the results of local control, survival rate, prognostic factors, and failure pattern in locally advanced esophageal cancer. Materials and Methods: We retrospectively studied 50 patients with locally advanced esophageal cancer treated with concurrent chemoradiotherapy at Keimyung University Dongsan Medical Center from June of 1999 to August of 2008. Seven patients with inappropriate data were excluded, and 43 patients were analyzed. There were 39 males and four female patients ranging in age from 43 to 78 years (median, 63 years). There were seven patients with stage IIA and 36 with stage III. Irradiation from 46 Gy to 63 Gy (median, 54 Gy) was carried out 5 days per week, 1.8 Gy once a day. There were eight patients with neo-adjuvant chemotherapy, and we mostly used 5-fluorouracil, cisplatin with 3 cycles for concurrent chemotherapy. The range of follow up periods was from 2 to 82 months (median, 15.5). Results: There were nine patients that exhibited a cornplete response, 23 that exhibited a partial response, 9 that exhibited no response, and 2 that exhibited disease progression. The median survival time was 15 months. Two-year and 5-year survival rates were 36.5% and 17.3%, respectively. Two-year and 5-year disease-free survival rates were 32.4% and 16%, respectively. Treatment failure occurred in 22 patients (51.2%). Patterns of failure were categorized as local failure in 18 patients and distant metastasis in four patients. In a univariate analysis for prognostic factors related to overall survival and disease-free survival, the hemoglobin levels during chemoradiotherapy (${\geq}$ 12 vs. <12, p=0.02(p=0.1) and the response to the treatments (CR/PR vs. NR/PD, p=0.002/p< 0.0001) were statistically significant. In a multivariate analysis, only response to the treatments was revealed to be statistically significant. There was no statistical significance associated with patient age, gender, disease stage, T-stage, smoking history, tumor location, or neo-adjuvant chemotherapy. Conclusion: Our survival rate was similar to those of other institutions. Local recurrence was the main reason for failure. It is suggested that further prospective studies should be performed to improve local control.

FAMILY DYNAMICS OF INCEST PERCEIVED BY ADOLESECENTS (청소년이 지각한 근친상간의 가족역동)

  • Kim, Hun-Soo;Shin, Hwa-Sik
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.56-64
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    • 1995
  • Family is a primary unit of the major socialization processing for children. Parents among the family members are one of the most important figures from whom the child and adolescent acquire a wide variety of behavior patterns, attitudes, values and norms. An organization of family members product family structural functioning. Abnormal family structure is one of the most important reference models in the learning of antisocial patterns of behavior. Therefore incest and child sexual abuse including spouse abuse, elderly abuse, and neglect occurs in the abnormal family structural setting. In particular, incest, a specific form of sexual abuse, was once thought to be a phenomenon of great rarity, but our clinical experiences, especially over the past decade, have made us aware that incest and child sexual abuse is not rare case and on the increasing trend. Therefore, the aim of this study was to determine the family problem and dynamics of incest family, and character pattern of post-incest adolescent victim in Korea. A total of 1,838 adolescents from middle and high school(1,237) and juvenile correctional institute(601) were studied, sampled from Korean student population and adolescent delinquent population confined in juvenile correctional institutes, using proportional stratified random sampling method. The subjects' ages ranged from 12 to 21 years. Data were collected through questionnaire survey. Data analysis was done by IBM PC of Behavior Science Center at the Korea university, using SAS program. Statistical methods employed were Chi-square, principal component analysis and t-test etc. The results of this study were as follows ; 1) Of 1,071 subjects, 40(3.7%) reported incest experiences(sibling incest : 1.6% ; another type of incest : 2.1%) in their family setting. 2) The character pattern of post-incest adolescent victim was more socially maladjusted, immature, impulsive, rigid, anxious and dependent than non-incest adolescent. Also they showed some problem in academic performance and their assertiveness. 3) The other family members of incest family revealed more psychological and behavioral problem such as depression, alcoholism, psychotic disorder and criminal act than the non-incest family, even though there is no evidence of the context between them. 4) The family dynamics of incest family tended to be dysfunctional trend, as compared with non-incest family. It showed that the psychological instability of family member, parental rejection toward their children, coldness and indifference among family member and marital discordance between the parents had significant correlation with incest.

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Correlation of serum total hydroperoxide levels and diseases of prematurity (미숙아 합병증 발생과 혈중 활성 산화물 농도와의 관계)

  • Kim, Shin-Hye;Hur, Hae Young;Lee, Kyu Hyoung;Moon, Ja Young;Chae, Kyu Young
    • Clinical and Experimental Pediatrics
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    • v.50 no.8
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    • pp.746-752
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    • 2007
  • Purpose : Total hydroperoxide (TH), free radical-mediated oxidation product can be used as a measure of free radical injury. The aim of the present study was to see if preterm newborns are at increased risk for oxidative stress compared with term newborns, and to determine whether oxidative stress during postnatal first 1 week is associated with clinical outcomes in preterm infants. Methods : Serum TH levels of preterm infants (n=39) were compared with those of term infants (n=24) on the postnatal day 1. Among the preterm infants, serum TH levels of uncomplicated group (n=23) were also compared with those of complicated group (n=16) who developed oxygen radical related diseases on the postnatal day 1 and 7. Retrospective analysis was performed to find out risk factors for oxygen radical injuries based on birth history, laboratory data, neuroimaging findings and clinical progress in two preterm groups. Results : Serum TH levels on postnatal day 1 were higher in the preterm infant group than the term infant group. Serum TH levels on postnatal day 1 in the complicated preterm infant group were significantly higher compared with uncomplicated group, but there was no significant difference in serum TH levels on postnatal day 7. Also, there was no significant difference in serum TH levels between uncomplicated preterm infants and term infants. Serum TH level on postnatal day 1 was independently associated with higher morbidity after adjusting for gestational age, Apgar score (5 min), arterial blood gas analysis. Conclusion : Complicated preterm newborns are at increased risk for oxidative stress compared with uncomplicated newborns and term newborns. Oxidative injury during the prenatal or postnatal day 1 is associated with adverse outcomes in preterm infants. Elevated TH levels on postnatal day 1 may have a value to predict clinical outcomes in preterm infants.

Associations of serum 25(OH)D levels with depression and depressed condition in Korean adults: results from KNHANES 2008-2010 (한국 성인의 혈청 25(OH)D 수준과 우울증 및 우울증상 경험과의 연관성: 국민건강영양조사 2008-2010 분석 결과)

  • Koo, Sle;Park, Kyong
    • Journal of Nutrition and Health
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    • v.47 no.2
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    • pp.113-123
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    • 2014
  • Purpose: Vitamin D has been known to play an important role in the central nervous system and brain functions in the human body, and cumulative evidence has shown that vitamin D deficiency might be linked with various mental health conditions. Epidemiologic studies have shown that vitamin D deficiency may be associated with higher risk of depression in the US and European populations. However, limited information is available regarding the association between vitamin D status and depression in the Korean population. The objective of this study was to examine the associations between vitamin D levels and prevalence of depression. Methods: We conducted a cross-sectional analysis using nationally representative data from the 2008-2010 Korean National Health and Nutrition Examination Survey from which serum 25-hydroxyvitamin D concentrations were available. A total of 18,735 adults who had available demographic, dietary, and lifestyle information were included in our analysis. We defined "depression" with a diagnosis by a physician. "Depressed condition" was defined as having feelings of sadness or depression without diagnosis by a physician. Results: The prevalence of depression was 1.63% and 5.43% in Korean men and women, respectively; 12.5% of men and 26.1% of women were defined as the group having depressed conditions. In multivariate logistic regression models, no significant associations were observed between vitamin D status and prevalence of depression or depressed conditions in Korean men and women. Conclusion: We found no association between vitamin D insufficiency and depression/depressed conditions in Korean adults. Future large prospective studies and randomized controlled trials are needed to confirm this relationship.

A study on evaluation of the image with washed-out artifact after applying scatter limitation correction algorithm in PET/CT exam (PET/CT 검사에서 냉소 인공물 발생 시 산란 제한 보정 알고리즘 적용에 따른 영상 평가)

  • Ko, Hyun-Soo;Ryu, Jae-kwang
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.1
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    • pp.55-66
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    • 2018
  • Purpose In PET/CT exam, washed-out artifact could occur due to severe motion of the patient and high specific activity, it results in lowering not only qualitative reading but also quantitative analysis. Scatter limitation correction by GE is an algorism to correct washed-out artifact and recover the images in PET scan. The purpose of this study is to measure the threshold of specific activity which can recovers to original uptake values on the image shown with washed-out artifact from phantom experiment and to compare the quantitative analysis of the clinical patient's data before and after correction. Materials and Methods PET and CT images were acquired in having no misalignment(D0) and in 1, 2, 3, 4 cm distance of misalignment(D1, D2, D3, D4) respectively, with 20 steps of each specific activity from 20 to 20,000 kBq/ml on $^{68}Ge$ cylinder phantom. Also, we measured the distance of misalignment of foley catheter line between CT and PET images, the specific activity which makes washed-out artifact, $SUV_{mean}$ of muscle in artifact slice and $SUV_{max}$ of lesion in artifact slice and $SUV_{max}$ of the other lesion out of artifact slice before and after correction respectively from 34 patients who underwent $^{18}F-FDG$ Fusion Whole Body PET/CT exam. SPSS 21 was used to analyze the difference in the SUV between before and after scatter limitation correction by paired t-test. Results In phantom experiment, $SUV_{mean}$ of $^{68}Ge$ cylinder decreased as specific activity of $^{18}F$ increased. $SUV_{mean}$ more and more decreased as the distance of misalignment between CT and PET more increased. On the other hand, the effect of correction increased as the distance more increased. From phantom experiments, there was no washed-out artifact below 50 kBq/ml and $SUV_{mean}$ was same from origin. On D0 and D1, $SUV_{mean}$ recovered to origin(0.95) below 120 kBq/ml when applying scatter limitation correction. On D2 and D3, $SUV_{mean}$ recovered to origin below 100 kBq/ml. On D4, $SUV_{mean}$ recovered to origin below 80 kBq/ml. From 34 clinical patient's data, the average distance of misalignment was 2.02 cm and the average specific activity which makes washed-out artifact was 490.15 kBq/ml. The average $SUV_{mean}$ of muscles and the average $SUV_{max}$ of lesions in artifact slice before and after the correction show a significant difference according to a paired t-test respectively(t=-13.805, p=0.000)(t=-2.851, p=0.012), but the average $SUV_{max}$ of lesions out of artifact slice show a no significant difference (t=-1.173, p=0.250). Conclusion Scatter limitation correction algorism by GE PET/CT scanner helps to correct washed-out artifact from motion of a patient or high specific activity and to recover the PET images. When we read the image occurred with washed-out artifact by measuring the distance of misalignment between CT and PET image, specific activity after applying scatter limitation algorism, we can analyze the images more accurately without repeating scan.

A Study on Cognition about 119 Rescue·First Aid Team - Gwangju Area College Student as the Central Figure - (119구조·구급대에 대한 인식도 조사 연구 - 광주지역 보건계열과 비보건계열 대학생을 중심으로 -)

  • Kim, Kab-Sun
    • The Korean Journal of Emergency Medical Services
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    • v.6 no.1
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    • pp.141-152
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    • 2002
  • The purpose of this study is to provide the basic materials for searching the way of improvement to heighten the emergency medical welfare level by one step further. To achieve this purpose, the subjects of this study were selected 452 college students in Gwangju, using a random sampling method. The statistical analysis methods utilized for analyzing the collected data are frequency analysis, $x^2$ test. The conclusions obtained from these analyses are as following ; 1. In question about necessary optimum number of persons for rescue first aid activity, health and non-health major college students responded by 39.2%, 45.3% respectively that rescue team 15 people, first aid team 3 people is most suitable. But there was no significant difference in major department(p<0.05). 2. In question about security of the public health doctor and the emergency medical technician, all health and non-health major college students are recognizing necessity urgently, but there was no significant difference in major department(p<0.05). 3. In question about 119 rescue first aid team member applying for an examination qualification grant to the department of EMT's graduate, all health and non-health major college students were highest by 52.9%, 52.4% respectively in "necessity" item. But there was no significant difference in major department(p<0.05). 4. Because rescue first aid equipment level appears higher than 41.7% in non-health major college student's case by 54.2% in health major college student's case, health major college students are recognizing that equipment level should be supplemented more but there was no significant difference in major department(p<0.05). 5. In question about equipment supplement, all health and non-health major college students appeared highest by 64.8%, 69.3% in accident type different special equipment. But there was no significant difference in major department(p<0.05). 6. In question about rescue ambulance car size, we could know being thinking that health and non-health major college student each 61.2%, 56.5% is small and narrow that large size of the rescue ambulance amount need. But there was no significant difference in major department(p<0.05). 7. In question about patient's state is worsened, because rescue first aid equipment is inferior, health major college student responded sometimes 55.1%, many 29.5%. very many by 11.5%, while non-health major college student responded 65.8%, 23.1%, 4.0% respectively. There was significant difference in major department(p<0.05). 8. In question about emergency patient must utilize for 119 rescue ambulance car, all health and non-health major college students appeared highest by 38.8%, 41.3% in "not so" item. In question about rescue first aid team's first-aid treatment ability improves more, all health and non-health major college students appeared highest by 58.1% and 58.7% respectively in "improve" item. In question about "119 rescue ambulance car must go more rapidly than now", all health and non-health major college students are recognizing that should be quicker by 58.1%, 60.9% respectively. When called to 119 all health and non-health major college students responded highest by 55.5%, 53.3% respectively that we must receive first-aid treatment direction from a doctor. In question about "119 rescue ambulance car must be made the pay system", all health and non-health major college students responded 74%, 80% respectively in "not so" item. There was significant difference in major department(p<0.05). In conclusions, In oder to provide superior rescue first aid service to people, a public health doctor should be placed in the situation room inside the fire station so that the doctor could instruct the proper emergency treatment suitable for each situation to the rescue first aid team. Also, national education about a first-aid treatment that do to all people is necessarily necessary in emergency delivery system and this should be spread extensively through school education and broadcasting medium and education should be gone side by side, and see that will can save emergency patients' life which is more when these education consists continuously fixed period for public institution of policeman, fire officer etc. specially. And for reinforcement of patient transfer system, public organization must procure special ambulance car so that emergency patient receive first aid treatment while transfer.

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A Study of the Representation in the Elementary Mathematical Problem-Solving Process (초등 수학 문제해결 과정에 사용되는 표현 방법에 대한 연구)

  • Kim, Yu-Jung;Paik, Seok-Yoon
    • Journal of Elementary Mathematics Education in Korea
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    • v.9 no.2
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    • pp.85-110
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    • 2005
  • The purpose of this study is to examine the characteristics of visual representation used in problem solving process and examine the representation types the students used to successfully solve the problem and focus on systematizing the visual representation method using the condition students suggest in the problems. To achieve the goal of this study, following questions have been raised. (1) what characteristic does the representation the elementary school students used in the process of solving a math problem possess? (2) what types of representation did students use in order to successfully solve elementary math problem? 240 4th graders attending J Elementary School located in Seoul participated in this study. Qualitative methodology was used for data analysis, and the analysis suggested representation method the students use in problem solving process and then suggested the representation that can successfully solve five different problems. The results of the study as follow. First, the students are not familiar with representing with various methods in the problem solving process. Students tend to solve the problem using equations rather than drawing a diagram when they can not find a word that gives a hint to draw a diagram. The method students used to restate the problem was mostly rewriting the problem, and they could not utilize a table that is essential in solving the problem. Thus, various errors were found. Students did not simplify the complicated problem to find the pattern to solve the problem. Second, the image and strategy created as the problem was read and the affected greatly in solving the problem. The first image created as the problem was read made students to draw different diagram and make them choose different strategies. The study showed the importance of first image by most of the students who do not pass the trial and error step and use the strategy they chose first. Third, the students who successfully solved the problems do not solely depend on the equation but put them in the form which information are decoded. They do not write difficult equation that they can not solve, but put them into a simplified equation that know to solve the problem. On fraction problems, they draw a diagram to solve the problem without calculation, Fourth, the students who. successfully solved the problem drew clear diagram that can be understood with intuition. By representing visually, unnecessary information were omitted and used simple image were drawn using symbol or lines, and to clarify the relationship between the information, numeric explanation was added. In addition, they restricted use of complicated motion line and dividing line, proper noun in the word problems were not changed into abbreviation or symbols to clearly restate the problem. Adding additional information was useful source in solving the problem.

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Comparative study on prevalence and components of metabolic syndrome and nutritional status by occupation and gender: Based on the 2013 Korea National Health and Nutrition Examination Survey (남녀별 직업군에 따른 대사증후군의 구성요소와 유병률 및 영양 상태의 비교 연구 : 2013년 국민건강영양조사 자료를 이용하여)

  • Kim, Ga Ram;Park, Hae Ryun;Lee, Young Mi;Lim, Young Suk;Song, Kyung Hee
    • Journal of Nutrition and Health
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    • v.50 no.1
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    • pp.74-84
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    • 2017
  • Purpose: In this study, factors of metabolic syndrome and nutritional status were examined according to gender and occupations using the 2013 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: This study was conducted on 1,750 workers (male : 892, female : 858) aged between 30 and 64, who participated in a health survey, health examination, and nutrition survey using the 6th 2013 KNHANES. Occupations were classified into white collar and blue collar workers, and nutrient intake was analyzed using a food frequency questionnaire. Analysis of complex sample design data through SPSS 19.0 was used for analysis. Results: The prevalence rate of metabolic syndrome among blue collar (35.1%) was higher than that among white collar workers (26.8%) in male subjects (p < 0.05) as well as in blue collar (24.8%) compared to white collar workers (8.9%) in female subjects (p < 0.001). Intake frequency per week, considering one portion by food category, showed significant differences in cooked rice (p < 0.05) and bakeries and confectioneries (p < 0.05) in make workers as well as stew and casserole (p < 0.01) and fruits (p < 0.05) in female workers. With regard to nutrient intake by occupation and gender, white collar workers consumed a greater amount of nutrients (not including total energy intake) compared to blue collar workers in both male and female workers. With regard to nutrient adequacy ratio (NAR) and mean adequacy ratio (MAR) according to gender and occupation, white collar workers showed higher numbers than blue collar workers in both male and female subjects. Conclusions: This study examined the prevalence rates of metabolic syndrome and nutrient intake according to gender and occupation. In both male and female subjects, blue collar workers showed higher prevalence rates compared to white collar workers, and their diet quality was worse than white collar workers' diet quality. Considering this result, customized nutrition education according to gender and occupation should be provided to workers to prevent diseases.

An Assessment of Notice Exposure by Job and Dosimeter Parameters Setting in Automobile Press Factory (자동차 프레스 공정에 있어서 직무 및 누적소음기 설정치 차이에 따른 작업자의 소음노출 평가)

  • Jeong, Jee Yeon;Park, Seunghyun;Yi, GwangYong;Lee, Naroo;You, Ki Ho;Park, Junsun;Chung, Ho Keun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.11 no.3
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    • pp.190-197
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    • 2001
  • Noise-induced hearing loss(NIHL) was the highest rate (43.5%~58.5% from 1996 to 1998) of positive findings through specific medical program in Korea. There were much more NIHL at workers of automobile manufacturing factories than other manufacturing factories. The specific aim of the present study was to determine the noise exposure of automobile press lines, according to their job titles, press line types(auto, semiauto), dosimeter parameters setting. There were a total 11 press lines sampled at a automobile manufacturing company. Among those press lines, 10 press lines were autolines with acoustic enclosure, one semiauto press line was no aucostic enclosure Noise exposure data were sampled for an work shift using noise dosimeter, which recorded both time-weighted average(TWA) and 1-min average. The mean OSHA TWA(Korea TWA with threshold 90) was $80.7dB(A){\pm}4.7dB(A)$ for leader, $82.8dB(A{\pm}4.5dB(A)$ for pallette man, $76.7dB(A){\pm}4.3dB(A)$ for press operators, $76.6dB(A){\pm}5.6dB(A)$ for crane operators, $77.1dB(A){\pm}2.8dB(A)$ for forklift drivers, whereas the mean NIOSH TWA was $88.9dB(A){\pm}1.7dB(A)$ for leader, $89.6dB(A){\pm}2.1dB(A)$ for pallette man, $86.7dB(A){\pm}1.8dB(A)$ for press operators, $88.5dB(A){\pm}2.0dB(A)$ for crane operators, $87.7dB(A){\pm}1.0dB(A)$ for forklift drivers. While L10 for NIOSH TWA samples was 84.8 dB(A) ~ 87.3 dB(A), L10 for OSHA TWA samples was 69.5 dB(A) ~ 77.4 dB(A). L10 means that the TWA for 90% of the samples exceeded L10. Among OSHA TWA(Korea TWA with threshold 90) samples for pallette man, 7.7 % exceeded 90 dB(A), the OSHA permissible exposure level, but OSHA TWA samples for the other job titles didn't. Among NIOSH TWA samples, the samples over 85 dB(A), the NIOSH recommended exposure limit, was 100% (leaders), 83.3 %(operators), 97.4%(palletteman), 100%(forklift drivers), 91.7 %(crane operator). The results of One-way random effects analysis of variance models shows that the difference between job titles was significant by OSHA TWA(p<0.05), but not significant by NIOSH TWA(p>0.05). NIOSH TWA samples were significantly higher than OSHA TWA samples(P<0.05). Regression analysis was used to obtain relationships between OSHA TWA samples and NIOSH TWA samples. In this case the coefficient of determination = 0.90, which shows the high degree association between two methods. Regression equation, NIOSH TWA = 0.552 * OSHA TWA + 42.13 dB(A), shows that if OSHA TWA is known, NIOSH TWA can be predicted by the equation. The mean TWA difference between threshold 80 dBA and 90 dBA was significant(p<0.01). While the TWA noise exposures were 7.7% above the Korea(OSHA) PEL, they were more than 83.3% over NIOSH REL. Automobile workers were exposed to noise level that could be potentially damaging to their hearing. It found that there is approximately 25% excess risk of hearing loss even if a worker is protected to the PEL in according to NIOSH study.

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