• 한국대기환경학회지
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• 제12권5호
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• pp.587-591
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• 1996

An intercomparison experiment was implemented to assess the uncertainties and precisions om atmospheric SO$_{2}$ measurement techiques including a pulsed fluorescence (P-F), a diffusion-scrubber /ion chromatography (D-I), and a mist-chamber/ion chromatography (M-I). Each of those three techniques was investigated by researchers at Seoul National University, Yonsei University, and Hankuk University of Foreign Studies, respectively. The concentrations of atmospheric SO$_{2}$ were determined concurrently using three independent measurement techniques at the Seoul National University campus, Korea during Nov.22 to Dec.2, 1995. While the results from the P-F and D-I techinques showed the very close agreements (within +-5%) throughout the experiment period, M-I technique showed systematically smaller values (up to 30%) than the other two techniques. Although sources of larger discrepancy between different techniques were mot identified, the lower SO$_{2}$ values of the M-I method may be related to the errors associated with sample collection effciency, mass flow rate measurements, and standardization of ion chromatography.

• 유통과학연구
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• 제11권6호
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• pp.13-19
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• 2013

Purpose - This study aims to predict the audit reports of listed companies on the Tehran Stock Exchange by using meta-heuristic algorithms. Research design, data, methodology - This applied research aims to predict auditors reports' using meta-heuristic methods (i.e., neural networks, the ANFIS, and a genetic algorithm). The sample includes all firms listed on the Tehran Stock Exchange. The research covers the seven years between 2005 and 2011. Results - The results show that the ANFIS model using fuzzy clustering and a least-squares back propagation algorithm has the best performance among the tested models, with an error rate of 4% for incorrect predictions and 96% for correct predictions. Conclusion - A decision tree was used with ten independent variables and one dependent variable the less important variables were removed, leaving only those variables with the greatest effect on auditor opinion (i.e., net-profit-to-sales ratio, current ratio, quick ratio, inventory turnover, collection period, and debt coverage ratio).

• 한국패류학회지
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• 제10권2호
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• pp.1-9
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• 1994

Molluscs from the Neolithic shell middens (Sugari, Pudjeong, Tongsamdong, Sangnodaedo, Sandeung, Yondaedo, Songdo and Kupyongri) in the southern coast, Korea, consisted of marine, fresh-water and land molluscs. Among these, intertidal species were exploited most abundantly as food resources, indicating a high dependence of intertidal shellfish collection activities. Especially oysters were the most abundant in these sites except Tongsamdong where mussels were predominant, indicating oysters were the most important food resources. Land snails from the sites consisted of woodland and open land species. Woodland species were more abundant than openland species, suggesting that there was a woodland environmint around the sites. Marine and land mollusc species from the sites are common in these rigions today, indicating no large-scale emvironmental changes have occurred since these middens formation period.

• 한국경영과학회지
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• 제41권3호
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• pp.59-74
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• 2016

Electricity sales are directly measured from individual consumers, which could minimize the time gap between data collection and public announcement. Furthermore, industrial electricity sales are highly linked with production and output. Therefore, industrial electricity consumption can be used to track production and output in real time. By using the high-frequency data of industrial electricity sales, this study develops the daily electricity business index (DEBI) to capture the daily economic status. The steps used to formulate DEBI are as follows: (1)selection of the explanatory variables and period, (2) amendment of the seasonal adjustment to eliminate daily temperature and effective day effects, (3) estimation of the weighted value via variables by using PCA, (4) calculation of DEBI and commencement of validation tests. Our empirical analysis and the Hodrick-Prescott filter analysis show that DEBI is highly related to existing economic indices.

• 환경위생공학
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• 제14권2호
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• pp.96-104
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• 1999

A questionary survey was conducted to investigate citizen's attitude to the treatment of food wastes in Miryang city. In this study, collection effectives was 87.8%, as 281 individuals among 320 individuals. After volume-base charge system, 86.8% of answers perform source separation and 60.9% of respondents separate everything of recycle goods. The majority of respondents discharge food waste using standard envelope. The biggest problems for deposition of the food wastes are offensive odor and worm for reasons of sanitation. Almost citizens think that the period of deposition suit from two days to three days. More than 90.0% of the citizens recognized that compost products made from food wastes and recognition of the people for the composting and composting facilities was affirmative. Majority of the respondents thought that the administration and the provincial government need activity publicity for the source separation fixations of the food wastes.

• 영어어문교육
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• 제15권3호
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• pp.171-198
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• 2009

The current study explored a pedagogical possibility of utilizing magic as a source of communicative tasks for young learners in developing their English speaking proficiency. Fifteen primary school students participated in the study, which consisted of a 17-week period of task-based English instruction and data collection. The participants were instructed to accomplish various types of magic task through collaborative group interaction. The data collected for the study pertained to the students' linguistic outputs, interactions in group and attitudes to English learning. They were analyzed for how magic tasks affect the students' English proficiency developments and group interactions. The study results suggested the significant improvement in the students' English speaking proficiencies. They revealed that magic tasks contributed to a) enhancing the motivation to speak in English, b) stimulating the creative and problem-solving processes, and c) providing the sufficient opportunity to repeat and internalize the target expressions. The study results also indicated that the students' satisfaction with their group members and tasks seemed to have positive influences on their interactions in group and English proficiency development. Further discussion and pedagogical implications are provided as well as the study limitations.

• 한국보건간호학회지
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• 제27권1호
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• pp.129-141
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• 2013

Purpose: This study examine the relationships retirement plans, perception of successful aging and attitude toward retirement nurses. Methods: The subjects of this study 200 nurses at two hospitals in C City. The data collection period from Nov. 1 to Dec. 31, 2011. Results: The degree of retirement significant according to age, marital status, education level, dependent, duration of employment, shift, department, annual salary. he degree of economic retirement plan showed significant differences according to age, marital status, education level, dependent home, duration of employment, department, annual salary. he degree of physical retirement plan showed statistically significant differences according to age, marital status, dependent, department. The degree of emotional retirement plan showed significant differences according to age, department. Conclusion: mprove the retirement of clinical nurse, we need a systematic based on physical and mental health.

• Journal of Forest and Environmental Science
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• 제32권1호
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• pp.39-54
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• 2016

The present study analyzes the diversity and usage of NTFPs and evaluates their importance in the day to day life of the people of rural Meghalaya. People use 172 NTFPs belonging to 139 plant species mainly for food, medicine and fuelwood and to a lesser extent for construction, handicrafts and ornamental purpose. These 139 plants belonged to 117 genera and 70 families with Rosaceae, Poaceae and Fagaceae families as the dominant NTFP yielding families. Fruits from shrubs and trees are most commonly harvested by people. Collection and availability of NTFPs for use as food are more during the summer season, which is also the period with least availability of job. NTFPs for subsistence use are greater in number than those having commercial value. The most commonly harvested plant parts are fruits and leaves. Roots, rhizomes and whole plants are extracted in lesser quantity which is a positive approach from sustainability point of view. NTFPs and other forest products also form a vital part of the rural household's income generation activities.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1030-1033
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• 2002

This paper, a new simple controller operates in continuous conduction mode (CCM) for Boost power factor collection converter is introduced. The duty ratios are obtained by comparisons of a sensed signal from inductor current and a negative ramp carrier waveform in each switching period. By using the proposed controller, input voltage sensing, error amplifier in the current feedback loop, and analog multiplier／divider are not required, then, the control circuit implementation is very simple. To verify the proposed controller, the circuit simulation for Boost power factor correction converter was applied. For the results, the input current waveform was shaped to be closely sinusoidal, implying low THD.

• 대한가정학회지
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• 제44권4호
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• pp.159-173
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• 2006

The purpose of this study was to investigate the seating style of children between Korea and USA viewed from activity analysis in child-care centers. Observation and depth-interview method were used for data collection. Ninety-eight children aged from 38 to almost 62 months were observed for five minutes three times during an indoor free play period in Korea and USA in 2003 and 2004. The results of the research were as follows. There were significant differences between the postures of Korean and American children. Korean children maintained floor-seating postures longer than chair-seating and standing postures. The factors such as sex, age and physical environment influenced the children's seating style, while playing-type influenced their posture. This study will contribute to our understanding of the physical environment and children's seating style according to culture.