• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.343-350
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• 2008

Many reports have warned of insufficient water supply in most countries in future and prospected providing safe and clean water become more difficult by lack of access to sustainable drinking water resources. Several facts and figures explained the impact by natural climate change and human activity results in the water scarcity and deterioration. Among many scientific solutions, the seawater desalination using a reverse osmosis membrane, so called SWRO (Seawater Reverse Osmosis) process, has been recognized as one of the most promising alternatives because of its stability and efficiency in producing large amount of drinking water from seawater through desalination by membrane filtration. Recently, in Korea, numerous researches are conducted to develop more productive and cost effective SWRO process for its wide implementation. The objective of this paper is to review the patents concerning SWRO technologies involving the plant engineering, maintenance including pretreatment of seawater and fouling control, module design, and mechanical units development for energy saving. The patents in Korea, U.S., Japan, Europe, and PCT were intensively researched and analyzed to provide the state of the art as well as leading edge technology on SWRO. This information can hopefully suggest meaningful guidelines on future research and development.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.686-691
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• 2005

Prolactin is considered to influence the taking of pauses in between ovulatory sequences in White Leghorn hens. Therefore modulating concentrations of prolactin using bromocriptine - a dopamine agonist during early life (17 to 36 weeks of age) could overcome the inhibitory effects of high concentration of prolactin on ovarian activity. The effect of modulation of prolactin concentration on egg production, sequence length and inter sequence pauses were studied by analyzing the oviposition records from 19 to 72 weeks were studied and compared with untreated controls. Bromocriptine administered subcutaneously (100 $\mu$g kg$^{-1}$ body weight or orally through feed (640 $\mu$g day$^{-1}$ bird$^{-1}$) resulted in a steady and sustained decrease in prolactin levels (p<0.01) during and after the withdrawal of treatment up to one reproductive cycle (72 weeks of age). The treated birds had comparatively longer sequences (p<0.01) and fewer pauses (p<0.01). Egg production increased (p<0.01) by fourteen per cent through subcutaneous administration and eleven per cent through oral feeding, over the control birds. It is concluded that the physiological pauses that occur during ovulatory sequences can be disrupted effectively using bromocriptine. Prolactin levels are modulated which may interfere with the follicular recruitment and subsequent oviposition thereby improve egg laying potential of the bird.

• Archives of design research
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• v.20 no.2 s.70
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• pp.103-116
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• 2007

Art education in design has repeatedly stressed the importance of developing creativity. In the digital period, however, which shows rapid change in both forms and contents, it needs to be equipped with more flexible and systematic ways of approaching to the creativity development, especially involved with cultural diversity of the digital world. This paper primarily proposes a maximally efficient, productive creativity learning program in which the integration of expressive media and communication generates a comprehensive network of communicative information in the development of digital technologies, which, consequently, brings forth valuable cultural contents of art. The amalgamation of Won (2006)'s Prism Effect, with distinctive three devices, and the facilitator factors, with two different facilitators such as self-controlled and controlled plays, would function as a catalyst for cultural diversity in the digital forms and contents of art. And this will, consequently, result in producing a number of practices that can be classified and assorted for a later performance. This paper thus suggests a roadmap of how to develop the creativity learning program in which two categories of facilitators based on three thinking devices function to classify four activities. In addition, selected activities are shaped as a creativity learning program by generating learning practices with the formalizing instructional strategy that fit into a specialized educational environment and learners. The samples of loaming practice design show guidelines for practice and the results of learning activity. Therefore, the eventual goal of this paper would be to establish a creativity learning program that constitutes a highly systematized and modularized database to maximize the efficiency and productivity of the creativity development.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.10
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• pp.111-117
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• 2008

Generally, speed control for Induction motor widely used in industrial field is accomplished by commercial inverter. Induction motor driven by commercial inverter causes the micro surge voltage because of high speed switching of inverter. Micro surge brings about not only the breakdown of motor but also noise in PLC control system. And they court the enormous interference in activity for production. In this paper, we suggest the suppressible countermeasure for the breakdown of motor after the consideration of productive mechanism about micro surge. Experiment is performed by inverter with LCR filler in its output terminal. As a result, we confirmed that micro surge voltage is reduced. And the suppressible countermeasure for the noise of PLC control system is suggested by theoretical consideration.

• Journal of Navigation and Port Research
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• v.31 no.2
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• pp.141-149
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• 2007

The competitiveness of container terminals hinges on minimizing the time vessels spend in port and on schedule services. Many previous researches on container terminals have tried to optimize the equipment allocation plan and to improve the activity of resources. Nevertheless, there have been few researches conducted on yard tractors, which move containers between the quay and the yard. The aim of this study is to propose the use of Real Time Location Systems (RTLS) based Dynamic Planning for yard tractors. Only RFID (Radio Frequency Identification) tags, which are attached to yard tractors, are able to support RTLS implementation. The system can provide real time job ordering in terms of load balancing using the information on location, in regards to the movement of yard tractors. This study will present the practical feasibility of RTLS, which can ultimately reduce the congestion of Hot Queues in container terminals. As a result, container terminals can be more productive and competitive. In order to accomplish the purpose of this study, we examined previous studies on the competitiveness of container terminals and summarized the potential of RTLS using RFID. In addition, we identified the role of yard tractors and proposed the two rules of Dynamic Planning for the yard tractors. We then fulfilled computational experiments on how yard tractors carrying containers by RTLS ordering Finally, the benefits and the implications of this study are discussed.

• Journal of the Economic Geographical Society of Korea
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• v.9 no.2
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• pp.243-260
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• 2006

The continuing enlargement, deepening integration of EU and penetration of extra-EU enterprise into EU market are forming a new geographical restructure of the production system. In this paper, I analyse the changing geography of the EU automotive production system. The globalization and regionalisation of production activity intensify a competition among the enterprise. The European automotive production system changes to a platform system and a modular system for a diminution of productive costs, a development of various products and a frequent innovation of products. The European automotive enterprise is restructuring geographically the production functions and products in order to promote efficiency on a new production system, enlarged production space and intensified economic integration. The European automotive industry tends to a spatial specialization and agglomeration according to the locational factors of production functions and products and the locational condition of regions. This intensifies the geographical hierarchic structure of production activity between the core and the periphery.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.7
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• pp.987-994
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• 2013

The purpose of this study was to evaluate the effect of natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) on broiler performance, gut morphology, intestinal length and weight, and gut digestive enzyme activity. A total of 240 d-old male chicks were randomly assigned to 3 treatments, each of which comprised 8 pens of 10 chicks per pen. Birds in the control group were fed the basal diet, while those in the experimental groups were fed diets supplemented with NCLI at 2% (NCLI group), or MCLI at 2% (MCLI group), respectively, for 42 d. Compared with the control, supplementation with NCLI or MCLI had no significant (p>0.05) effects on productive parameters from d 1 to 42. Supplementation with NCLI or MCLI had no influence on the relative length and weight of small intestine at d 1 to 21. But supplementation with NCLI or MCLI significantly reduced the relative weight of duodenum. Supplementation with MCLI and NCLI was associated with greater (p<0.05) villus height in the jejunal and ileal mucosa compared with those areas in the controls from d 1 to 42. However, supplementation with NCLI and MCLI had no significant (p>0.05) influence on the crypt depth in the jejunal and ileal mucosa compared with those in the controls. The addition of either NCLI or MCLI to the diet improved the activities of total protease, and amylase in the small intestinal contents. In conclusion, supplementation with NCLI or MCLI in diets improved intestinal morphology, increased the intestinal length and weigh and gut digestive enzyme activity.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.246-259
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• 2013

The purpose of this study was to investigate the differential effects of the determinants of life satisfaction among the elderly and a variety of health, economic, leasure activity, social support and psychological variables were comprehensively examined as determinants of life satisfaction among the elderly. The sample of this study was composed of 347 old people participating in the leasure activity programs operated by 10 facilities for the aged in Seoul. Data were collected using structured questionnaires and analyzed employing structural equation modelling technique as a main data analysis method. It was found that subjective health condition, subjective economic level, productive and consumptive leasure activities, spouse and children support, self-esteem and extraversion had positive effects on life satifaction among the elderly. The theoretical and practical implications of this study were discussed and the directions for future research were suggested.

• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.217-230
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• 2014

The purpose of this study is to develop the Generalized Depreciation Function (GDF) and Winfrey Depreciation Function (WDF) by reviewing methods for the depreciation accountings. The Depreciation Accounting Models (DAM), including straight-line model, declining-balance model, sum-of-the-year-digit model and sinking fund model presented in this paper, are reclassified into the charging pattern of increasing type, decreasing type and constant type. This paper also discusses the development of the GDFs based on convex type, concave type and constant type according to the demand pattern of product, frequency of plant usage, deterioration of time, relative inadequacy, Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) of the Total Productive Maintenance (TPM). The WDFs presented in this paper depict a sudden degradation of plant performance by measuring the change of TPM activity at the midpoint of useful life of asset. The WDFs are classified into left-modal type, symmetrical type and right-modal type by varying the value of skewness and kurtosis. Moreover, three increasing patterns, such as convex, concave and linear types, are used in this paper to present the distinct identification of WFDs by using Instantaneous Depreciation Rate (IDR) in terms of Performance Depreciation Function (PDF) and Depreciation Density Function (DDF). In order to have better understanding of depreciation models, the numerical examples are used for evaluating the Net Operating Less Adjusted Tax (NOPLAT) and Economic Value Added (EVA). It is concluded that the depreciation models showing a large dispersion of EVA require the adjustment of NOPLAT and Invested Capital (IC) based on the objective cash basis and net operating activity for reducing the variation of EVA.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.208-215
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• 2016

Vaccinium oldhamii Miq. is a Korean native tree, which is deciduous and shrub tree with broad leaf. Fruits were used primarily for edible or medicinal purposes for bladder infection in Korea and China. However, there is a lack of information on the degree of variation of phytochemical contents and antioxidant activity of these native clonal. We investigated morphological characteristics, phytochemical contents (polyphenol, flavonoid, anthocyanin) and antioxidant activity for the fruits of 24 individual variation from 4 different regions in Korea. The results in terms of horticultural traits and biochemical characteristics showed significant differences among populations and among individuals within population. The total phenolic contents ranged from 4.40 to 10.58 mg GAE/g and the total flavonoid contents ranged from 2.02 to 8.09 mg NE/g. The total anthocyanin contents ranged from 232.5 to 684.3 mg CGE/100g. Reducing power fruits ranged from 0.15 to 1.43 and DPPH free radical scavenging activity ranged from 49.1 to 97.5% at 400 ppm. Results revealed that the region of origin greatly influenced the phytochemical contents and antioxidant activity of V. oldhamii, which might help for the selection and validation of the most productive cultivars in the food and pharmaceutical industries.