• Information Systems Review
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• v.25 no.3
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• pp.27-41
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• 2023

Unlike the previous works focusing on the state-of-the-art methodologies to improve the performance of machine learning models, this study improves the 'quality' of training data used in machine learning. We propose a method to enhance the quality of training data through the processing of 'local grammar,' frequently used in corpus analysis. We collected a vast amount of unstructured corporate review text data posted by employees working in the top 100 companies in Korea. After improving the data quality using the local grammar process, we confirmed that the classification model with local grammar outperformed the model without it in terms of classification performance. We defined five factors of work engagement as classification categories, and analyzed how the pattern of reviews changed before and after the COVID-19 pandemic. Through this study, we provide evidence that shows the value of the local grammar-based automatic identification and classification of employee experiences, and offer some clues for significant organizational cultural phenomena.

• Safety and Health at Work
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• v.15 no.2
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• pp.220-227
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• 2024

Background: Though the artificial neural network (ANN) technique has been used to predict noise-induced hearing loss (NIHL), the established prediction models have primarily relied on cross-sectional datasets, and hence, they may not comprehensively capture the chronic nature of NIHL as a disease linked to long-term noise exposure among workers. Methods: A comprehensive dataset was utilized, encompassing eight-year longitudinal personal hearing threshold levels (HTLs) as well as information on seven personal variables and two environmental variables to establish NIHL predicting models through the ANN technique. Three subdatasets were extracted from the afirementioned comprehensive dataset to assess the advantages of the present study in NIHL predictions. Results: The dataset was gathered from 170 workers employed in a steel-making industry, with a median cumulative noise exposure and HTL of 88.40 dBA-year and 19.58 dB, respectively. Utilizing the longitudinal dataset demonstrated superior prediction capabilities compared to cross-sectional datasets. Incorporating the more comprehensive dataset led to improved NIHL predictions, particularly when considering variables such as noise pattern and use of personal protective equipment. Despite fluctuations observed in the measured HTLs, the ANN predicting models consistently revealed a discernible trend. Conclusions: A consistent correlation was observed between the measured HTLs and the results obtained from the predicting models. However, it is essential to exercise caution when utilizing the model-predicted NIHLs for individual workers due to inherent personal fluctuations in HTLs. Nonetheless, these ANN models can serve as a valuable reference for the industry in effectively managing its hearing conservation program.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.5
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• pp.41-50
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• 2024

An increasing pattern of extreme rainfall recently affected the rural infrastructures with catastrophic damage, especially the overtopping of a fill dam embankment in the Republic of Korea. The overtopping was caused by the sudden increase in reservoir water level over the dam crest level, and it was not easy work to predict a priori because of its non-linear behavior. Fuzzy time series (FTS) is a fuzzy-logic inference procedure and is suited to apply to non-linear prediction methods such as machine learning. This study used the Wangshin reservoir and Goesan-dam cases, which experienced overtopping in 2023 and 2022, respectively. Wangshin Reservoir was a typical agricultural fill dam and needed to stack more available data, with only the daily storage rate (water level) of 7 years, starting on 2 May 2016. Therefore, we used Goesan-dam data to select appropriate variables and compare the analysis result, which was stacked with about 17 years of records. The analyses adapted LSTM to compare with FTS. As a result, the reservoir water level was applied to predict the overtopping water level, and it was shown that the FTS method could predict the actual water levels effectively according to the result of comparison with LSTM. Then, the FTS method was expected to predict reservoir water level a priori to make appropriate countermeasures on overtopping events as one of the alternatives.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.592-600
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• 1997

Background : The level of imposed work of breathing (WOB) is important for patient-ventilator synchrony and during weaning from mechanical ventilation. Triggering methods and the sensitivity of demand system are important determining factors of the imposed WOB. Flow triggering method is available on several modern ventilator and is believed to impose less work to a patient-triggered breath than pressure triggering method. We intended to compare the level of imposed WOB on two different methods of triggering and also at different levels of sensitivities on each triggering method (0.7 L/min vs 2.0 L/min on flow triggering ; $-1\;cmH_2O$ vs $-2cm\;H_2O$ on pressure triggering). Methods : The subjects were 12 patients ($64.8{\pm}4.2\;yrs$) on mechanical ventilation and were stable in respiratory pattern on CPAP $3\;cmH_2O$. Four different triggering sensitivities were applied at random order. For determination of imposed WOB, tracheal end pressure was measured through the monitoring lumen of Hi-Lo Jet tracheal tube (Mallincrodt, New York, USA) using pneumotachograph/pressure transducer (CP-100 pulmonary monitor, Bicore, Irvine, CA, USA). Other data of respiratory mechanics were also obtained by CP-100 pulmonary monitor. Results : The imposed WOB was decreased by 37.5% during 0.7 L/min on flow triggering compared to $-2\;cmH_2O$ on pressure triggering and also decreased by 14% during $-1\;cmH_2O$ compared to $-2\;cmH_2O$ on pressure triggering (p < 0.05 in each). The PTP(Pressure Time Product) was also decreased significantly during 0.7 L/min on flow triggering and $-1\;cmH_2O$ on pressure triggering compared to $-2\;cmH_2O$ on pressure triggering (p < 0.05 in each). The proportions of imposed WOB in total WOB were ranged from 37% to 85% and no significant changes among different methods and sensitivities. The physiologic WOB showed no significant changes among different triggering methods and sensitivities. Conclusion : To reduce the imposed WOB, flow triggering with sensitivity of 0.7 L/min would be better method than pressure triggering with sensitivity of $-2\;cm\;H_2O$.

• Journal of agricultural medicine and community health
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• v.13 no.1
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• pp.3-18
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• 1988

The general objective of this research is to study behavioral pattern of health care utilization and to measure the level of utilization of the traditional medicine. The specific objective is to study utilization pattern and content of folk medicine which is the indegenous medical technology recognized part of traditional medicine. This research was under taken to generate valid information that will provide basis data for formulating general direction for health education activities and for designing service package for general population. A social survey method was employed to obtain required information for the research activities, The survey field team consisted of 20 surveyors who all participated is an intensive 2 day training course. A total of 3091 households were visited and interviewed by the field team during the period 7 September to 6 October 1987. The major findings obtained from the information collected by the field survey are as follows ; 1) General characteristics of the study households 2562 households out of 3091 households visited were selected for final data process, 80.2 of the selected households were nuclear families ; 17.4%, extended families ; others 2.4%. Only 4.3 percent of the study population in the urban households indicated "no schooling" whereas 14.2% of the rural household members falls within this category. Study population in the urban areas are more protected against diseases by the national medical insurance system than those in rural areas. In their self appraisal of living standard, those who responded with low group are 39.6% and 50.3% respectively by urban and rural households. 2) Morbidity status Period prevalence rate for all diseases during the preceding 15 days before the date of the household interview v as 243,0 per 1,000 study population. For cases with the illness duration of within 15 days, the initial points of medical entry were diversied ; 56.9%, drug stores ; 30.9%, clinics and hospitals ; 4.6% folk medicine ; 1.7% clinics of Korean oriental medicine. Among the chronic case; with illness duration of over 90 days, 34.6% of these people utilized clinics and hospitals of modern medicine ; 31.6%, drug stores ; 18.6% clinics of Korean oriental medicine ; 6.8% folk medical techniques. Noticeable is the almost ten fold increase from the mere 0.9% in the utilization of Korean oriental medicine, whereas in the utilization of folk medicine, it is short of two-fold increase. 3) Folk medicine and its utilization Households that use folk medicine for relief and care of signs and symptoms commonly encountered in daily life, number 1969 households, which accounts for 76.9% of all the study households. This rather high level use of folk medicine is not different from rural to urban areas. The order of frequency of utilizing folk medicine among the study people are : the highest 14.3% for the relief of indigestion ; 8.6% for burns ; 5.1% for common cold ; 4.7% for hiccough ; and 4.2% for hordeolum. A present various procedures of folk medicine is being used to relieve all kinds of symptoms. 192 symptoms are identified at present. The most frequently used procedures of folk medicine appear to be based either on principles of the Korean oriental medicine or of scientific knowledge. Based on these survey findings, proposals for utilizing folk medicine are as follows First, this survey's findings will be feed back to both on the job training and on the spot guidance of community health practitioners, public health nurses and other peripheral work force in the health field, who are in daily contacts with community. This feed back will assure that the health personnel carry out their health education and information activities that are based on the utilization pattern of folk medicine as found in the survey result. Second, studies will be soon implemented that are designed to measure the efficiency and potency of these procedures and to improve these procedures of folk medicine were most frequently used by the community. Third, studies will continue to systematize medicinal plants and skills of Korean oriental medicine that are easily available at minimal cost in daily life for the prevention of diseases and management of emergency cases.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.574-582
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• 1997

Background : Normal humans meet the increased ventilatory need during exercise initially by the increase of tidal volume (TV) and later by the increase of respiratory frequency (Rf). And the inspiratory duty cycle (Ti/Ttot) is also increased more than 50% for the compensation of the decrease of respiratory cycle provoked by the increase of respiratory frequency. The patients with chronic airflow obstruction show rapid and shallow breathing pattern during exercise because of the decreased ventilatory capacity and the increased dead space ventilation. However, the studies about the change of inspiratory duty cycle are only a few and there is no literature about the relationship between the change of inspiratory duty cycle and the degree of airflow obstruction. Methods : The subjects were the twelve patients with chronic airflow obstruction (CAO) and ten normal people. The incremental exercise test was done. The increase of work load was 10 W in CAO group and 25 W in normal control group. The analysis of the results was done by the comparison of the parameters such as minute ventilation (VE), TV, Rf, physiologic dead space (Vd/Vt), and inspiratory duty cycle between the two groups. Each parameters were compared after transformation into % control duration base that means dividing the total exercise time into five fractions and % control duration data were obtained at rest, 20%, 40%, 60%, 80%, and max. Statistical analysis was done by repeated measure ANOVA using SAS program. Results : The changes of VE and TV were significantly different between two groups while the change of Rf was not significant. The decrease of Vd/Vt was significantly low in CAO group. Ti/Ttot was markedly increased from 38.4 + 3.0% at rest to 48.6 + 4.5% at max in normal control group while Ti/Ttot showed little change from 40.5 + 2.2% at rest to 42.6 + 3.5% at max. And the change of inspiratory duty cycle showed highly good correlation with the degree of airflow obstruction (FEV1%). (r=0.8151, p < 0.05). Conclusions : The increase of Ti/Ttot during exercise observed in normal humans is absent in the patients with CAO and the change of Ti/Ttot is well correlated with the degree of airflow obstruction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.848-857
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• 2018

Recently, around the world, active development of new renewable energy sources including solar power, waves, and fuel cells, etc. has taken place. Particularly, floating offshore wind farms have been developed for saving costs through large scale production, using high-quality wind power and minimizing noise damage in the ocean area. The development of floating wind farms requires an evaluation of the Maritime Safety Audit Scheme under the Maritime Safety Act in Korea. Floating wind farms shall be assessed by applying the line and area concept for systematic development, management and utilization of specified sea water. The development of appropriate evaluation methods and standards is also required. In this study, proper standards for marine traffic surveys and assessments were established and a systemic treatment was studied for assessing marine spatial area. First, a marine traffic data collector using AIS or radar was designed to conduct marine traffic surveys. In addition, assessment methods were proposed such as historical tracks, traffic density and marine traffic pattern analysis applying the line and area concept. Marine traffic density can be evaluated by spatial and temporal means, with an adjusted grid-cell scale. Marine traffic pattern analysis was proposed for assessing ship movement patterns for transit or work in sea areas. Finally, conceptual design of a Marine Traffic and Safety Assessment Solution (MaTSAS) was competed that can be analyzed automatically to collect and assess the marine traffic data. It could be possible to minimize inaccurate estimation due to human errors such as data omission or misprints through automated and systematic collection, analysis and retrieval of marine traffic data. This study could provides reliable assessment results, reflecting the line and area concept, according to sea area usage.

• The Research Journal of the Costume Culture
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• v.3 no.2
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• pp.241-260
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• 1995

The Maori's traditional clothing materials, basic forms of dress, and the pattern and technique of tatoo were examined in the present study in order to deepen the appreciation of the cultural heritage of the Maori. The research method employed was the analysis of written materials. And a fild-trip was also made for the study. The study was limitted to the traditional culture of body adornment of the Maori including the clothing which is preserved and practicing by them at the present day, and the origin and the process of the historical development of those are not included in the scope of the present study. Followings are the results of the study: (1) By far the most widely used fiber for Maori clothing is abtained from what is commonly called New Zealand Flax. The fiber of kiekie(Freycinetia baueriana) and cabbage trees(Cordyline spp.) may also be used. The strong, long-lasting fiber of toi(cordyline indivisa) is used for a prestige warrior's cloak. Flat strips of ti kauka(Cordyline australi) are also used as thatch on rain cloaks. (2) Regardless of technique used, Maori weaving is always worked horizontally from left to right. Traditionally the work was suspended between two upright turuturu or weaving sticks. As the work progressed a second pair of uprights was used to keep the work off the ground. These uprights were moved forward as required. Because the weaver sat on the ground, the working edge was kept at a height that was comfortable to reach. No weaving tools are used, the wefts(aho) being manipulated by the fingers. The two main Maori weaving techniques are whatu aho patahi(single-pair twining) and whatu aho rua(double-pair twining). (3) The Maori wore two basic garments - a waist met and a cloak. The cloth of commoners were of plain manufacture, while those of people of rank were superior, sometimes being decorated with feather or dyed tags and decorated borders. Children ran more-or-less naked until puberty, being dressed only for special events. Some working dress consisted of nothing more than belts with leaves thrust under them. Chiefs and commoners usually went barefoot, using rough sandals on journeys over rough country (4) The adornment of men and women of rank was an important matter of tribal concern as it was in chiefly persons that prestige of the group was centred, The durable items of Maori persons adornment were either worn or carried. Ornaments of various kinds were draped about the neck or suspended from pierced earlobes. Combs decorated the head. Personal decorations not only enhanced the appearance of men and women, but many had protective magical function. The most evident personal ornament was the hei-tiki made of jade or other material. Maori weapons were treasured by their owners. They served on bottle and were also personal regalia. A man of rank was not fully dressed without a weapon in hand. Also weapons were essential to effective oratory. (5) No man or woman of rank went without some tattoo adornment except in extremely rare instances when a person was too sacred to have any blood shed. The untattooed were marked as beeing commoners of no social standing. This indelible mark of rank was begun, with appropriate rite and ritual, at puberty. And tattoo marked the person as being of a marriageable age. Maori tattoo was unlike most traditional tattoo in that its main line were 'engraved' on the face with deep cuts made by miniature bone chisels. The fill-in areas were not tattooed with cuts but with the multiple pricks of small bone 'combs' that only lightly penetrated the skin surface. The instrument of tattoo consisted of small pots of pumice or wood into which was placed a wetted black pigment made from burnt kauri gum, burnt vegetable caterpillars or other sooty materials. A bird bone chisel or comb set at right angles on a short wooden handle was dipped into the gigment, that a rod or stick was used to tap head of this miniature adze, causing penetration of the skin surface. Black pigment lodged under the skin took on a bluish tinge. A full made facial tattoo consisted of major spirals with smaller spirals on each side of the nose and sweeping curved lines radiating out from between the brows over the forehead and from the nose to the chin. The major patterns were cut deep, while the secondary koru patterns were lightly pricked into the skin.

• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.1-12
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• 1992

To assess the pattern of psychiatric symptoms and to evaluate the relationship between exposure related variables(duration of work and urinary hippuric acid concenturation) and psychiatric symptoms in organic solvent exposed workers, case control study of forty-two solvent exposed workers and ninethy-six non-exposed workers was conducted. The general health questionnaire 28(GHQ28) was administered to evaluate psychiatric symptoms and urinary hippuric acid concenturations was measured to estimate the present status of solvent exposure in exposed group and to estimate normal level in non-exposed group. The mean concenturation of urinary hippuric acid was significantly higher in exposed group (2.953g/creatinine g) than non-exposed group(0.395g/creatinine g) (P<0.01). The total positive rates of symptoms were significantly higher in exposed group(28.2%) than non-exposed group(17.5%)(P<0.05). The positive rates of symptoms for four sub-scales of GHQ28 in exposed group were in the order of somatic symptoms, anxiety, social dysfunction, depression and in the order of social dysfunction, anxiety, depression, somatic symptoms in non -exposed group. The positive rates of symptoms for somatic symptoms and anxiety were significantly higher in exposed group than non-exposed group (P<0.05) and the proportion of workers with six or more positive symptoms(dysthymic states) in exposed group were significantly higher than non-exposed group (P<0.01). After the effect of age, sex, level of income, level of education, and duration of work were controlled, the total score of GHQ28 was still significantly different between exposed and non-exposed group(P<0.01). In multipile logistic regression analysis on the dysthymic state, the odds ratio of level of income was statictically significant in both group. The odds ratios of exposure related variables such as duration of work and hippuric acid concenturations were not statistically significant but there was a tendency that exposure related variables had an affect on dysthymic state in exposed group. In future, continuous evaluation of psychiatric symptoms on organic solvent exposed workers and studies to detect the factors that affect on psychiatric symptoms are required.

• Korean Journal of Occupational Health Nursing
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• v.8 no.2
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• pp.193-211
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• 1999

This study was carried out to investigate the management and support system affecting to the occupational health nursing services(OHNS) provided in group occupational health agencies(GOHA). Questionnaire was developed and distributed to 82 nurses who were working in GOHA and who agreed to participate in the survey. The results were as follow: 1. OH nurses responded were mostly in the age of twenty to thirties(89%), married(73.7%), technical college graduates(88.9%), worked in hospital(85.4%) and participated more than 1 year in group occupational health services (96.3%). 2. Fifty eight point four percent of the OH nurses worked in number of workplace more than 30 to less than 60 in the OHNS form. The figure of workplaces undertaken by nurses was ranged greatly from 9 to more than 100. Number of employees who cared by nurses were mostly under 5,000 peoples in 93.3%. The types of industry was mostly manufacturing and located in the order of factory complex area, suburban, urban and others. 3. Most OH nurses(87.8%) were fully involved in the OHNS for the SSE. Their working days to visit SSE was 5 days per week(77.8%) and one day in the GOHA at 41.3%. 4. The OH documents using by nurses were found in more than 23 different types. However, they were largely summarized in the types of 'Workplace Health Management Card', 'Personal Health Counselling Card', 'Daily Health Management Report', 'Visiting List of Workplace' and 'Sick Employee List'. 5. The items of laboratory test provided by GOHA were mostly achieved in the purpose of basic health examination. They were used to be the blood pressure check(98.8%), blood sugar test (98.8%), urine sugar and protein(91.4%), SGOT and SGPT(85.3% each), cholesterol (82.9%), hepa vaccine immunization(82.9%), r-GPT(81.7%), hemoglobin(79.3%) and triglyceride(75.5%). 6. The OH nurses(92.7%) followed the work pattern to visit the GOHA before and after small-scale enterprises(SSE) visit by car driven by nurses in 74.3%. They were payed by GOHA for transportation fees in certain amounts. However, nurse is the main person(75.0%) who covers up in case of traffic accident. If the GOHA has no transportation regulation for the formal workplace visit, data showed that nurses had been responsible to take charge(31.7%). 7. The personnel manager who takes in charge for nursing services was 'nurse' in 61.7% and 41.2% worked as the final decision maker related to nursing work. The OH nurses' opinions about factors affecting to the management were classified in the four areas such as 'Nature(Quality) of health professional'. 'Content of OHNS', 'Delivery system of the GOHS', and 'Others'. The factors were indicated highly in 'Authority as health professional', 'Level of perception of director on the OH' and 'Physical work condition for OHNS'. The things that this study suggests in the recommendation would be summarized in such as the management and supporting system working for SSE in the OHNS is necessary to reform thoroughly. The reconsidered aspects might be in the matters of number of workplaces undertaken by nurses, development of effectively practical health documents, preparation for guideline of the laboratory test in the workpleces, establishment of convenient and encouraging support system and cooperation between other health professionals with respect and skill.