• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.49-52
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• 2013

An experiment to investigate the natural circulation of a cryogen has been performed. The study is motivated mainly by our recent development of cryogenic cooling system for prototype superconducting cyclotron without any circulating pump. In the natural circulation loop system, a cooling channel is attached on the outer surface of the aluminium block and the liquid nitrogen passes through inside of the channel to cool the block indirectly. A cryocooler as a heat sink is located at the top to re-condense cryogenic vapor coming from the aluminium block in which electrical heater is installed as a heat source. The main dimensions are determined using the relevant analysis and the natural circulation loop is successfully fabricated. The temperature distributions in the loop are measured during initial cool-down process and in steady state, from which the modified Grashof numbers are calculated and compared with the existing correlation estimated with one-dimensional analysis for steady state flow.

• Korean Journal of Pharmacognosy
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• v.26 no.1
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• pp.23-26
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• 1995

6-Hydroxykynurenic acid and ginkgolide B together with flavonol glycosides and biflavonoids were isolated from the yellow leaves of Ginkgo biloba and identified by means of spectroscopic methods. The correctness of $H{\"{o}}lzl's$ ${13}^C-NMR$ assignments for 6-hydroxykynurenic acid was confirmed by HMQC and HMBC techniques. Based on our present findings, it may be considered that the yellow Ginkgo leaves may contribute to be a source of high medicinal values.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.3
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• pp.99-104
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• 2007

The most extensively used synthetic antioxidants are butylated hydroxyanisole (BHA), butylated hydroxy toluene (BHT) and tert-butylhydroquinone (TBHQ). However BHT and BRA have been suspented of being responsible for liver damage andcar cinogenesis. Therefore, the importance of the search and exploitation of natural antioxidant, especially of plant origin, has greatly increased in recent years. Plant contain a wide variety of chemicals that have potent biological effects. As a result, there has been a growing interest in the use of herbs as a source of therapeutic drugs. The aim of this study was to assess the antioxidant and cosmeceutical of natural materials. The antioxidant and cosmeceutical activity of natural materials were investigated by hydroxyl radical scavenging, superoxide dismutase (SOD) -like, xanthine oxidase inhibition, tyrosinase inhibition, anti-microbial and astringent.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.59-64
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• 2018

In this paper, we investigated the alternative sources of limestone. Oyster shell waste originated from aquaculture that causes a major disposal landfill problem in coastal sectors in southeast Korea. Their inadequate disposal causes a significant environmental problems araised. Bio mineralization leads to the formation of oyster shells and consists $CaCO_3$ as a major phase with a small amount of organic matter. It is a good alternative material source instead of natural lime stone. The utilization of oyster shell waste for industrial applications instead of natural limestone is major advantage for conservation of natural limestone. The present work describes the limestone and oyster shells hydraulic activity and chemical composition and characteristics are most similar for utilization of oyster shell waste instead of natural limestone.

• Science of Emotion and Sensibility
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• v.5 no.3
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• pp.29-34
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• 2002

This study aimed to investigate the effect of design factors of woven textiles on the consumer's sensibility and emotion. 60 textile design pictures and 18 adjectives were prepared to get responses from 512 adult subjects. Textiles designs were analyzed into 9 design factors, such as, motif source, motif-background ratio, motif interpretation, motif arrangement, motif variation, motif articulation, hue contrast, value contrast, and chroma contrast. The results are followings: 1) The design factors of textiles were connected to other design factors, for example, the type of motif interpretation determined the type of chroma contrast, motif source, the ratio, and chroma contrast significantly. 2) The correlational coefficients of the ratio, motif variation, chroma contrast, hue contrast, articulation, and value contrast were positively signed significantly. 3) Consumer's sensibility was changed in urban, natural, graceful, mannish, young, dynamic, new, modem and etc, as the textile designs were changed in motif source, arrangement, hue contrast and etc.

• Journal of Sensor Science and Technology
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• v.24 no.5
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• pp.299-305
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• 2015

Since the natural disasters such as floods, droughts, heat wave and cold wave are increasing, the need for risk management is necessary to minimize the damage with utilizing IT technology. Also, the monitoring services of disaster response type have been developed and applied. Recently, the open source hardware based on the signal of the sensor, or the monitoring studies have been carried. In this paper, by analyzing a low-cost open source hardware platform such as Beagle board, we examine the utilization of the hardware-based module for sensor monitoring.

• Asian Journal of Turfgrass Science
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• v.26 no.1
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• pp.67-71
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• 2012

Organic fertilizers are divided into natural organic and synthetic organics. The benefits of natural organic fertilizer were reported from the previous researches. The previous researches have reported that clippings are nitrogen source for turfgrass growth. However, the limited research results about clippings as a source of natural organic fertilizers were reported. The objective of the research to investigate effects of liquid fertilizer produced from fermented clippings for creeping bentgrass growth. Liquid fertilizer (LF) produced was used for the research to be compared with urea and two natural organic fertilizers of different source (NO-1 and NO-2). Kentucky bluegrass (Poa pratensis L., Midnight) was used for the study. Turfgrass quality was measured by visual evaluation every two weeks from June to October, 2011 using a scale of 1 to 9 (1=worst, 6=acceptable, and 9=best). LF produced greater turfgrass quality than acceptable quality, especially with the summer period while urea and NO produced lower turfgrass quality than acceptable quality of 6. LF had less quality alteration than urea and NO during the study. Based on the result of the study, LF are more stable to maintain turfgrass quality than urea and NO.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.41-44
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• 2002

Blind source separation (BSS) is a fundamental problem that is encountered in many practical applications. In most existing methods, stationary sources are considered higher-order statistics is necessary either explicitly or implicitly. But, many natural signals are nonstationary, and it is possible to perform BSS using only second-order statistics. Our method is based on only second order statistics. The algorithms are developed using the gradient descent method in orthogonality constraint and their performance is confirmed by numerical experiments.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1513-1520
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• 2009

Forty-six Holstein heifers were used in a completely randomized design and assigned to 1 of 2 treatments to evaluate the effects of 2 diets varying in ruminal fermentable carbohydrate sources, namely ground corn (GC) and rolled wheat (RW), on metabolism and performance of primiparous cows in the periparturient period. The heifers were fed diets as a total mixed ration (TMR) with similar energy and crude protein content including i) 18.57% GC, or ii) 18.57% RW from -24.13${\pm}$7.73 d relative to expected calving until calving. After calving, all animals received the same lactation diet until 28 d. Animals were group fed from the beginning of the study to -7 d relative to expected calving, fed individually from d -7 to 7 days in milk (DIM), and again group fed to 28 DIM. The pre-partum diets affected (p<0.05) dry matter intake (DMI), energy intake, energy balance (EB) and urinary pH during the last week pre-partum. There was no effect of pre-partum carbohydrate source on overall plasma concentration of glucose, nonesterified fatty acid (NEFA), $\beta$-hydroxybutyrate (BHBA), albumin, triglyceride (TG), cholesterol, aspartate aminotransferase (AST), insulin, and cortisol during the periparturient period. Cows fed the RW diet during the pre-partum period had greater calcium for the first week (p<0.05) and during 28 d (p = 0.08) of lactation compared with heifers fed the GC diet. Primiparous cows fed the RW diet produced greater milk protein content and yield (p<0.05). Primiparous cows fed the RW diet had lower milk urea nitrogen (MUN) and somatic cell count (SCC) than cows fed the GC diet (p<0.05). The results of this study show that feeding pre-partum diets with a rapidly fermentable source of starch but low energy content can improve animal metabolism and performance and smooth the transition of primiparous Holstein cows from gestation to lactation.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.237-242
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• 2004

Cell growth and the production of pullulan by Aureobasidium pullulan HP-2001, the UV-induced mutant of A pullulans ATCC 42023, increased with increased concentration of glucose up to 15.0% (w/v). Maximal production of pullulan in the flask scale was 27.65 g/l, when concentrations of glucose and yeast extract were 15.0 and 0.25% (w/v), respectively. Maximal conversion rate of pullulan from glucose as the carbon source was 0.37, when those of glucose and yeast extract were 5.0 and 0.15% (w/v), respectively. On the basis of total amount of pullulan, the conversion rate of pullulan from glucose, and utilization rate of glucose to cell mass and pullulan by A. pullulans HP-2001, the optimal concentrations of glucose and yeast extract for the mass production of pullulan were determined to be 10.0 and 0.25% (w/v), respectively, at which concentrations the production of pullulan and its conversion rate were 27.14 g/l and 0.27, respectively. Maximal production of pullulan with optimized concentrations of carbon and nitrogen sources by A. pullulans HP-200l in a 7-1 bioreactor was 32.12 g/l for 72 h culture, and that in a 100-1 bioreactor with the inner pressure of $0.4 kgf/cm^2$ was 36.87 g/l. Increased inner pressure of a 100-1 bioreactor resulted in a higher concentration of dissolved oxygen in the medium, which might enhance the production of pullulan by A. pullulans HP-2001.