• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.238-246
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• 2012

Organic matters budget in Lake Hoengseong were monthly investigated from April 2009 to November 2009. The intense rainfall occurred at between July and August and the hydrological factors were highly varied during the rainfall season. By the concentrated rainfall, the elevation, influx and efflux were sharply increased and the turbid water was also flowed into the middle water column in Lake. The inflow of turbid water increased the nutrient concentrations in water body and this appears to stimulate of phytoplankton regard as the primary productivity of influx of organic matter. Monthly average concentration of dissolved organic carbon (DOC) was generally higher than the particulate organic carbon (POC) concentration in Lake, but Temporal and spatial variation of POC concentration was higher than DOC and the maximum POC concentration was recorded in surface water in August, had the highest phytoplankton biomass. Organic carbon concentration in inflow site was rarely changed during the dry season, but the concentration was rapidly increased by the initial intense rainfall. In organic matters budget, the most of the organic matters was inflowed from the inflow site at rainfall season. Especially, the influx of allochthonous organic matters during the intense rainfall was 72.4% in the total influx organic matters.

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.720-731
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• 2014

There are many kinds of optical systems to widen a field of view. Fisheye lenses with view angles of 180 degrees and omni-directional systems with the view angles of 360 degrees are recognized as proper systems to widen a field of view. In this study, we proposed a new optical system to overcome drawbacks of conventional omni-directional systems such as a limited field of view in the central area and difficulties in manufacturing. Thus we can eliminate the undesirable reflection components of the omni-directional system and solve the primary drawback of the conventional system. Finally, tolerance analysis using Zernike polynomial coefficients was performed to confirm the productivity of the new optical system. Furthermore, we established a method of optical axis alignment and compensation schemes for the proposed optical system as a result of tolerance analysis. In a sensitivity calculation, we investigated performance degradation due to manufacturing error using Code V(R) macro function. Consequently, we suggested compensation schemes using a lens group decentering. This paper gives a good guidance for the optical design and tolerance analysis including the compensation method in the extremely wide angle system.

• KIEAE Journal
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• v.11 no.1
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• pp.39-45
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• 2011

The concepts of interior design work have set forward an aesthetic and functional proposition to be answered by those who design spaces. The available range of suitable materials for interior use appears to be almost inexhaustible in this day and age. Now a day, relatively new fields of study on environmental-friendly interior examine humans'innate affinity for health and explore its implications for architecture and the built environment. A growing field of research suggests that spaces' relationship to aesthetics and environment can either help or hinder their occupants' health and wellness, productivity, and even their creativity. This paper presents several examples of already built apartment houses in practice, and discusses the demand of users of the spaces for health and sustainable environment, deepening the relationship between newly-constructed spaces and the remodeled ones. The considerations to some new and contemporary materials from the aspect of healthy indoor architecture design are presented in this paper. Designers need to rethink the conventional and high-tech interior environment in apartment houses with respect to perceived air quality, material emissions, and odors. The future of interior design is oriented on light shapeable materials which are able to create a unique memorable atmosphere. The primary assignment in accepting recent materials and proceedings is our responsibility to creating proposals, that are mainly safe, hygienic and environmentally proper.

• Journal of Korean Academy of Nursing
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• v.38 no.4
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• pp.612-619
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• 2008

Purpose: The purpose of this study was to examine health problems and to estimate economic impact based on health problems of workers. Methods: The subjects of this study consisted of 301 workers who received a group occupational health service. Data was collected from February 1 to March 30, 2006. The questionnaire contained questions based on general characteristics and the Stanford Presenteeism Scale. Data was analyzed with descriptive statistics, t-test using SPSS program. Results: The primary health conditions as reported by workers were ranked in order as stomach or bowel disorders, back or neck disorders, or liver function disorders. The reason of absenteeism per worker was ranked in order as asthma, or a breathing disorder. The reason of presenteeism was ranked in order as asthma, insomnia or a sleep disorder. The cost of the total economic impact on the workplace in this study was 8,851,838 won. The cost of absenteeism per worker was 8,390 won. The cost of presenteeism per worker was 941,732 won. Conclusion: Presenteeism had a strong correlation to health conditions of the workers. Therefore, improving the work conditions of the workers is very important. If employers improve the health condition of workers, they will benefit from improved productivity in their business.

• Journal of the Korean Solar Energy Society
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• v.30 no.1
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• pp.25-33
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• 2010

Use of daylight in underground space interacts with physiological need for human beings and provides relief from feeling secluded. Light pipe system can deliver natural light into the space where it is needed and can be used as primary or a secondary light source with benefits of energy, productivity and health. To use light pipe system effectively under various conditions, it is important to investigate the effectiveness of light pipe system with reliable monitoring protocol. This paper presents the results of light pipe system performance used in underground parking lot under different sky conditions. Comparisons were made between the illuminance standards of underground parking lot and the monitored data. The results indicated that adequate illuminance level was shown until 4.5m distance from the light pipe under clear sky condition. However, additional lighting device showed be used under overcast sky to meet the proper illuminance level.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.1-7
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• 2011

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose and lignin surrounds the cellulose component of the plant's cell wall in order to protect the cell from enzymatic attacks. Such resistance, along with the variability seen in the proportions of the major components of the mixture, presents process design and operating challenges to the bioconversion of lignocellulosic biomass to fuel. Expanding bioenergy production to the commercial scale will require a significant improvement in the growth of feedstock as well as in its quality. Plant biotechnology offers an efficient means to create "targeted" changes in the chemical and physical properties of the resulting biomass through pathway-specific manipulation of metabolisms. The successful use of the genetic engineering approach largely depends on the development of two enabling tools: (1) the discovery of regulatory genes involved in key pathways that determine the quantity and quality of the biomass, and (2) utility promoters that can drive the expression of the introduced genes in a highly controlled manner spatially and/or temporally. In this review, we summarize the current understanding of the transcriptional regulatory network that controls secondary wall biosynthesis and discuss experimental approaches to developing-xylem-specific utility promoters.

• Journal of Ecology and Environment
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• v.36 no.3
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• pp.193-204
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• 2013

Altitudinal patterns of plant species richness and the effects of area, the mid-domain effect, climatic variables, net primary productivity and latitude on observed richness patterns along the ridge of the Baekdudaegan Mountains, South Korea were studied. Data were collected from 1,100 plots along a 200 to 1,900 m altitudinal gradient on the ridge. A total of 802 plant species from 97 families and 342 genera were recorded. Common and rare species accounted for 91% and 9%, respectively, of the total plant species. The altitudinal patterns of species richness for total, common and rare plants showed distinctly hump-shaped patterns, although the absolute altitudes of the richness peaks varied somewhat among plant groups. The mid-domain effect was the most powerful explanatory variable for total and common species richness, whereas climatic variables were better predictors for rare plant richness. No effect of latitude on species richness was observed. Our study suggests that the mid-domain effect is a better predictor for wide-ranging species such as common species, whereas climatic variables are more important factors for range-restricted species such as rare species. The mechanisms underlying these richness patterns may reflect fundamental differences in the biology and ecology of different plant groups.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.477-488
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• 2020

This study provides the empirical testing to test the influences of contemporary leadership styles (i.e., transactional and transformational) on job satisfaction and customer satisfaction as the mediating variable between job satisfaction and customer loyalty. The approach utilized in this study was a quantitative research design using a survey model. The participants of this study were recruited from 160 front-liners in the airline's industry in Indonesia. This study employed 160 front liners (flight attendants, reservation/ticketing, and check-in-counter officers) who worked in Branch Office/General Sales Agent of Indonesian commercial airlines. The studied airlines serve domestic routes based at Soekarno-Hatta International Airport. Furthermore, the data were examined the four developed hypotheses by using Structural Equation Modeling (SEM). The primary results are: First, in the context of job satisfaction, both leadership styles (i.e., transactional and transformational) have similar influences; Second, job satisfaction affects customer satisfaction positively and significant, Third, customer loyalty is driven by passengers' satisfaction when they are utilizing the airline services. The findings imply that the working-role encouragement is essential to maximize the productivity of front-liners to serve their customer well. This research supports on developing the general knowledge based on leadership styles in the context of the airline's industry in managing the human resources strategically.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.292-295
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• 1990

The bacterial strain KH-1167, identified as Ctoetridiunt sp. was found to produce the antibiotics KG-1167A & KG-1167B which showed a broad spectrum antibacterial activity. The highest antibiotics production was obtained in fermentation medium containing glucose, casamino acid and salt complex solution. Optimum culture condition for the maximum production of the antibiotics was also determined. Antibiotic productivity of the Clostridium sp. KH-1167 was increased to about 450% compared to that in the medium used for the primary isolation procedure.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.12
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• pp.25-33
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• 2003

A burr has been defined as undesirable projection of material formed as a result of plastic flow from a cutting or shearing operation. It is unavoidable in all kinds of machining operation. As a result, burr makes troubles on manufacturing process due to deburring cost, quality of products and productivity. In this study, the primary interest is about exit burr. The burr formation mechanism in each type of burr is classified. Data bases are developed to predict burr formation result. In the milling operation, we develop an algorithm to analyze the burr formation mechanism by the geometrical analysis on the multi featured workpiece with multi cutting path. The algorithm includes three steps, i. e., the feature identification, the cutting condition identification, and the analysis on exit burr formation. We can predict which portion of workpiece would have the exit burr in advance so that we can manage to find a way to minimize the exit burr formation in an actual cutting. Also, this algorithm can be implemented in a commercial CAM package so that we can simulate the NC code to review the burr formation in advance.