• Title/Summary/Keyword: 군.경

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Performance of PN Code Based Time Hopping Sequences in M-ary Ultra Wide Band Multiple Access Systems Using Equicorrelated Signal Sets (동일 상관 신호군을 이용하는 M-ary UWB 다원 접속 시스템에서 PN 부호 기반 시간 도약 시퀀스의 성능)

  • 양석철;신요안
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10A
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    • pp.816-829
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    • 2003
  • In this paper, we evaluate the performance of PN (Pseudo Noise) code based time hopping sequences for M-ary UWB (Ultra Wide Band) multiple access systems using the equicorrelated signal sets. In particular, we consider two different types of M-ary UWB systems in UWB indoor wireless multipath channels: The first type of the systems (System #1) has identical symbol transmission rate regardless of the number of symbols M since the length of signal pulse train is fixed while M increases, and the second type of the systems (System #2) has the same bit transmission rate regardless of M since the length of signal pulse train is extended according to the increase of M. We compare the proposed systems with those using the ideal random time hopping sequence in terms of the symbol error rate performance. Simulation results show that the PN code based time hopping sequence achieves quite good performance which is favorably comparable to that of the ideal random sequence. Moreover, as M increases, we observe that System #2 shows better robustness against multiple access interference than System # 1.

In Vivo Experiment of Tissue-Engineered Artificial Vessel (조직공학적 인조혈관의 생체 내 이식 실험)

  • 임상현;조승우;홍유선;김병수;유경종;장병철;최차용
    • Journal of Chest Surgery
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    • v.37 no.3
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    • pp.220-227
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    • 2004
  • The number of patients with coronary artery disease and peripheral vascular disease are increasing, and the need of small diameter vessel is also increasing. We developed small diameter artificial vessel and experimented in vivo. We got allogenic valve from mongrel dogs, and removed all cells from the allogenic valve. Then, we seeded autologous bone marrow cells onto the decellularized scaffold. After implantation of artificial vessel into the canine carotid artery, we performed angiography regularly. In case of vessel occlusion or at 8 weeks after operation, we euthanized dogs, and retrieved the implanted artificial vessels. Control vessels were all occluded except one (which developed aneurysmal dilatation). But autologous cell seeded vascular graft were patent by 4 weeks in one, by 6 in one and by 8 weeks in two. Histologic examination of patent vessel revealed similar structure to native artery. Tissue-engineered vascular graft manufactured with decellularized allogenic matrix and autologous bone marrow cells showed that tissue engineered graft had similar structure to native artery.

Effects of Pre-drying Process on the Quality of 'Fuyu' Persimmons (예건 처리 온도에 따른 단감(부유)의 품질 변화 조사)

  • Park, Sung Jin;Cho, Kwang Sik;Kim, Jun Tae
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.21 no.2
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    • pp.79-84
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    • 2015
  • Pre-drying of 'Fuyu' persimmon was performed right after harvesting from a farm. Pre-drying conditions were varied with room temperature (RT) for 1 day to 7 days, low temperature (LT, at $20{\sim}30^{\circ}C$) for 1 day to 4 days, high temperature (HT, at $30{\sim}40^{\circ}C$) for 3 h to 12 h, and ultra-high temperature (UT, at $50{\sim}60^{\circ}C$) for 30 min to 120 min. Weight loss of pre-dried persimmon was increased from 1.62% up to 2.96% with increased pre-drying temperature and time. Pre-drying at RT resulted more significant weight loss of persimmon compared to that of pre-drying at HT. Minimum firmness loss of persimmon stored at $0^{\circ}C$ for 100 days was obtained at the condition of HT for 6 h. Rate of peel blackening was decreased from 31.5% to 16.4% and 10.9% by pre-drying at HT for 6 h and 9 h, respectively.

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Deep Seawater Increases Dendritic Branches of Cultured Rat Hippocampal Neurons (해양심층수에 의한 해마신경세포 가지돌기 수의 증가)

  • Lee, Hyun-Sook;Nam, Kyung-Soo;Shon, Yun-Hee;Moon, Il-Soo
    • Journal of Life Science
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    • v.18 no.6
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    • pp.897-901
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    • 2008
  • Deep seawater (DSW; deep ocean water) is pure, rich in inorganic materials which have attracted attention for various applications. In this study we investigated the effects of the DSW upwelled from the East Sea, offshore Yang Yang (Korea) on the morphological differentiation of cultured rat hippocampal neurons, which were grown in the minimal essential medium containing 10% (v/v) fetal bovine serum and 25% (v/v) DSW with various hardness. DSW had no effect on initial morphological differentiation (17 hr post-plating). When observed on DIV3, 7, 14, and 17, low hardness (0 and 200) DSW reduced dendritic branching. However, dendritic branches within $80\;{\mu}m$ diameter from the center of soma nearly doubled in neurons grown in hardness 1,000 DSW-containing media. DSW with hardness 600 was more or less same as control groups. These results indicate that DSW with appropriate hardness ameliorates neuronal health.

Effect of Spice Powder on the Characteristics of Quality of Bread (향신료를 첨가한 식빵의 품질특성)

  • 김미림;박금순;박찬성;안상희
    • Korean journal of food and cookery science
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    • v.16 no.3
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    • pp.245-254
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    • 2000
  • The purpose of this study was to provide the basic information for bread with kinds of spice. The qualities of bread added with garlic, ginger, and cinnamon powder were investigated using sensory and mechanical evaluation. The result of sensory evaluation showed that the softness, color, brittleness, hardness, and chewiness of bread were increased as the amount of garlic, ginger and cinnamon powder increased. Lightness decreased by the addition of garlic, ginger and cinnamon powder, while redness and yellowness increased. Texture measurement showed that hardness, cohesiveness, springiness, gumminess and brittleness were the lowest in the breads with 1% garlic, ginger and cinnamon powder, and increased as the added amount of spice increased. A positive correlation was observed between the sensory and mechanical properties in general, while hardness and chewiness have negative correlation with sensory properties. Sensory properties of wheat flour odor, roasted taste, springiness and swelling were positively correlated with the acceptability. Breads with 1% garlic, ginger, and cinnamon powder showed a good overall preference.

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A New Genetic Algorithm for Shortest Path Routing Problem (최단 경로 라우팅을 위한 새로운 유전자 알고리즘)

  • ;R.S. Ramakrishna
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.12C
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    • pp.1215-1227
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    • 2002
  • This paper presents a genetic algorithmic approach to shortest path (SP) routing problem. Variable-length chromosomes (strings) and their genes (parameters) have been used for encoding the problem. The crossover operation that exchanges partial chromosomes (partial-routes) at positionally independent crossing sites and the mutation operation maintain the genetic diversity of the population. The proposed algorithm can cure all the infeasible chromosomes with a simple repair function. Crossover and mutation together provide a search capability that results in improved quality of solution and enhanced rate of convergence. Computer simulations show that the proposed algorithm exhibits a much better quality of solution (route optimality) and a much higher rate of convergence than other algorithms. The results are relatively independent of problem types (network sizes and topologies) for almost all source-destination pairs.

Effect on Oral Health and Child Oral Health-related Quality of Life through School-based Toothbrushing Program in School after 42 Months (42개월 경과시점의 양치교실사업이 구강건강과 아동 구강건강관련 삶의 질에 미치는 효과)

  • Cho, Min-Jeong;Koong, Hwa-Soo;Hwang, Soo-Jeong;Song, Eun-Joo;Choi, Yu-Kyoung
    • Journal of dental hygiene science
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    • v.12 no.2
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    • pp.139-144
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    • 2012
  • Daejeon school-based toothbrushing program using toothbrushing room started at 2007. Ministry of Health and Welfare started national toothbrushing room program without pilot project at 2011. The aim of this study was to provide the basic data to assess of the effect of this program. 59 experimental subjects and 60 control subject were selected after written consent. Oral Examination was done by 1 dentist using WHO standard and Survey of Child Oral Health-Related Quality of Life(COHIP), oral health knowledge and oral health behavior were done using self-registration form. We analyzed the result after adjusting economic status and subjective for the difference between experimental and control groups using SPSS 19.0. The experimental group had lower plaque index, better COHIP and more oral health knowledge significantly(p<0.05). But, The significance was not found in dental caries index and oral health behavior. We suggested the oral health education program and other dental caries prevention program including sealants were needed to prevent dental caries, although school-based toothbrushing program could improve COHIP.

Quality Characteristics and Amino Acid Content of Cookies with GABA-Enhanced Brown Rice (GABA 함량이 증가된 현미 첨가 쿠키의 품질특성과 아미노산 함량)

  • Jung, Hae Won;Chung, Hai-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.11
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    • pp.1813-1820
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    • 2013
  • This study is conducted to investigate the quality characteristics of cookies containing different levels (0%, 20%, 40%, 60%) of brown rice powder with enhanced levels of GABA (${\gamma}$-amino butyric acid). The pH of cookie dough was higher in cookies containing brown rice powder. A proximate composition analysis showed that the moisture content was increased with the addition of the brown rice powder, yet there was no significant difference in the crude protein and crude fat contents among the added groups. The ash content was the highest in the 60% added group. The spread factor of the control cookie was higher than that of cookies containing 40% and 60% brown rice powder. The incorporation of brown rice powder in cookies lowered the lightness and yellowness values, but increased the redness value. The hardness of the cookies was lower in 40% and 60% added groups than that of the controls. The GABA content in the brown rice added groups was higher than that of the control cookie, and increased as brown rice powder increased. A consumer acceptance test revealed that there was no significant difference in the overall preference scores among the cookies. From these findings, it is suggested that the cookies with brown rice powder up to 60% added can be developed as goods.

Prevention of Quality Deterioration in Concentrated Strawberry Puree by Employing pH Regulators during Heat Treatment (pH 조절제를 이용한 농축 딸기 퓌레 열처리 시 품질저하 억제)

  • Lee, In-Gyeong;Min, Seo-Cheol;Kim, Hee-Sun;Han, Gwi-Jung;Kim, Myung-Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.10
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    • pp.1518-1524
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    • 2016
  • This study was performed to minimize quality degradation of concentrated strawberry puree after $90^{\circ}C$ for 5 min by heat treatment with citric acid (CA) and acidic sodium metaphosphate (ASM) as pH modifiers. The highest color value was 1% CA+1% ASM (13.027), followed by 1% CA (9.539) and control (6.905). Anthocyanin contents were also 1% CA+1% ASM (3.049 mg/100 g), 1% CA (1.140 mg/100 g), and control (0.757 mg/100 g) in sequence. The DPPH radical scavenging activities of control, 1% CA, and 1% CA+1% ASM were 58.148, 72.638, and 83.736%, respectively. The color values, anthocyanin contents, and DPPH radical scavenging activities were significantly different at P<0.05 between control and 1% CA+1% ASM treatment. For the results of overall preference for hedonic test, there was no significant difference at P>0.05 among the three samples. During heat treatment, quality degradation of concentrated strawberry puree was reduced by 1% CA+1% ASM treatment, which is expected for new acidulants.

Mechanism of Decrease in Lung Injury by Low Dose of Endotoxin During Hyperoxia in the Rats (저용량의 내독소가 쥐에서 고농도의 산소에 의한 급성폐손상을 경감시키는 기전)

  • Song, Jeong-Sup;Yoon, Hyung-Kyu;Kim, Young-Kyoon;Kim, Kwan-Hyung;Moon, Hwa-Sik;Park, Sung-Hak
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.2
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    • pp.148-160
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    • 2002
  • 배 경 : 쥐를 고농도의 산소에 60시간 이상 노출시켰을 때 급성 폐손상이 유발되지만 내독소를 저용량으로 투여시에는 이러한 폐손상이 경감된다고 알려져 있으나 그 기전에 대하여는 확실히 밝혀지지 않고 있다. 산화질소(nitric oxide, NO)는 내독소나 염증성 사이토카인(cytokine) 등의 자극에 의해서 폐내 여러 염증세포에서 만들어지며 이 산화질소는 경우에 따라 우리 몸에 이롭거나 해로운 양면성을 지니고 있다. 저자들은 쥐에서 고농도의 산소에 의한 폐손상이 저농도의 내독소 투여로 경감되는 기전에, 산화질소가 중요한 역할을 하는지 또는 황산화효소나 다른 항염증성 사이토카인이 중요한 역할을 하는지를 규명하고자 하였다. 방 법 : 총 120마리의 쥐 (Sprague-Dawley rat)를 24마리씩 5군으로 나누어 대조군은 실내 공기를, 고농도 산소군은 100%의 산소를 100%의 산소를 60시간 투여하였고 내독소군은 100% 산소 투여시 2일간 저용량의 내독소를 투여하였다. 다른 두 군은 산화질소 합성 억제물인 aminoguanidine(AG)과 N-nitro-L-arginine methyl ester (L-NAME)를 각각 2일간 고농도 산소와 내독소에 더하여 투여하였다. 각각의 군에서 폐손상의 정도와 사망률을 관찰하고 superoxide dismutase(SOD), catalase, nitric oxide, IL-6, IL-11을 기관지폐포세척액에서 측정하고, 고농도산소 투여군의 폐조직에서 iNOS synthase rnRNA의 발현을 비교하였다. 결 과: 1. 100%의 산소에 60시간 노출시켰을 때 쥐의 사망률은 8.3% 이었고 내독소 투여군은 4.2%, NAME 투여군이 37.5%, AG 투여군이 25%로 산화질소 합성 억제제에 의하여 사망률의 증가가 관찰되었다. 2. 폐의 손상 정도를 나타내는 폐의 wet/dry 중량비와 늑막액도 100%의 산소에 노출된 군에서 증가되었고 내독소 투여에 의하여 감소되었으며 NAME나 AG 투여군에서는 오히려 증가되었다. 3. 이러한 내독소에 의한 폐손상 억제효과가 항산화효소인 SOD나 catalase, 또는 protective cytokine인 IL-6나 IL-11등의 증가와 관련이 있는지를 관찰하였으나 이들 모두에서 유의한 변화를 관찰하지 못하였다. 4. 산화질소는 100% 산소에 노출시킨 군에서도 증가하였으나 내독소 투여군에서 유의하게 더욱 증가하였고 이는 L-NAME 나 aminoguanidine의 투여시 감소하였다. 5. iNOS mRNA의 발현도 내독소 투여군에서 유의하게 증가하였다. 결 론 : 쥐의 고농소 산소 투여에 의한 폐손상은 저용량의 내독소 투여로 경감되며, 이는 주로 내독소 투여에 의한 iNOS mRNA의 발현을 유도하여 생성된 산화질소의 증가에 기인하는 것으로 생각된다.