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The Variation of Natural Population of Pinus densiflora S. et Z. in Korea (IX) -Needle and Wood Characteristics of Six Populations- (소나무천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(IX) -광주(廣州), 제천(堤川), 보은(報恩), 무주(茂朱), 구례(求禮), 제주집단(濟州集團)의 침엽(針葉) 및 재질형질(材質形質)-)

  • Yim, Kyong Bin;Lee, Kyong Jae
    • Journal of Korean Society of Forest Science
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    • v.44 no.1
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    • pp.1-25
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    • 1979
  • Six natural populations of Pinus densiflora S. et Z. as shown in the location map (Flg 1) were studied during 1978. The numerial pouplation codes, 13 to 18. The results of populations 1 to 12 were reported in previous papers. Following the study methods described before, 20 trees were sampled from each population and morpological characteristics such as stem forms, branching habit needle and wood properties investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 36 to 97 of years. The growth performances of trees of population 14. 15 and 18 was similar, but 13, 16, and 17 seemed to be inferior more or less. 2. The ratios of clear bole length were 0.70 in population 18 as the highest but 0.28 for population 16 as the lowest. 3. The population 17 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown height) 158 though the branching angles were almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between population as shown In Fig. 3 and 4. 5. As to the serration density, number of stomata row and resin duct; the significant differences exist between individual trees within population and also between populations. 6. Population 18 shown resin duct index 0.119 as the maximum. 7. The patterns of diameter growth, based on the width of 10-year-ring segment unit(for example, the 1st segment denotes the with between pith center and 10th year ring and the 2nd one is from 11th to 20th ring and so on.), were alike among populations as shown in Fig 9. 8. Significant differences between population in mean summer wood percentage as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 14, 18 however vice versa in population 13, 15, and 17. 9. The fiber length was mereased with the increased of age but no differences between populations as shown in Fig. 12.

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Photosynthesis by Leaf Age and Fruit Characteristics by Fruiting Nodes in Vertical and Hydroponic Cultivation of Oriental Melon Applied with Air Duct for High-temperature Season (고온기 송풍 덕트 적용 수직·수경재배 참외의 엽령별 광합성과 착과 절위별 과실 특성)

  • Youngsin Hong;Sohyun Park;Sungwook Yun;Jinkyung Kwon;Siyoung Lee;Sanggyu Lee;Jongpil Moon;Jaekyung Jang;Hyojun Bae;Jeongsu Hwang
    • Journal of Bio-Environment Control
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    • v.32 no.2
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    • pp.89-96
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    • 2023
  • This study was conducted to apply with an air duct for the cooling and a utilizing cultivating method that uses the fruiting node and the defoliation to the high-temperature vertical and hydroponic cultivation of the oriental melon. The lower fruiting node (LF) was to remove all third vines generated from 5 nodes of a secondary vine. The higher fruiting node (HF) was fruiting on the third vine generated from a first node of the third vine. The direction of the stem string; upward (UW), downward (DW). Four treatment conditions were applied with the LF-UW, LF-DW, HF-UW (control), and HF-DW. The leaf age of melon leaves was measured for photosynthesis at 3 days intervals, and the fruit characteristic was conducted on 79 fruits in each treatment. The photosynthesis rate steadily increased after leaf development, reaching 20.8 μmol CO2·m-2·s-1 on the 10 days, gradually increasing to 21.3 μmol CO2·m-2·s-1 on the 19 days, and reaching 23.4 μmol CO2·m-2·s-1 on the 32 days. After that, it lowered to 16.8 μmol CO2·m-2·s-1 on the 38 days and dropped significantly to 7.6 μmol CO2·m-2·s-1 on the 47 days. As a result of the fruit characteristics by fruiting nodes, the treatments of the fruit length was 12.6-13.4 cm, respectively, which was significant, and the fruit width was 7.9- 8.6 cm, respectively, was not significant. The soluble content ranged from 12.9 to 15.7°Brix, and the significance of all treatments, and higher than of LF-DW and HF-UW. The photosynthesis rate of melon leaves was good until 32 days after leaf development, but after that, the rate decreased. As for fruit quality, it was conformed that melons can be cultivated at the LF because the fruit enlargement and soluble content dose not decrease even when set at the LF. Results indicated that those can be used for LF and defoliation in the development of vertical and hydroponic cultivation method in high-temperature season.

The Variation of Natural Population of Pinus densiflora S. et Z. in Korea (V) -Characteristics of Needle and Wood of Injye, Jeongsun, Samchuk Populations- (소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(V) -인제(麟蹄), 정선(旌善), 삼척집단(三陟集團)의 침엽(針葉) 및 재질형질(材質形質)-)

  • Yim, Kyong Bin;Kwon, Ki Won;Lee, Kyong Jae
    • Journal of Korean Society of Forest Science
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    • v.36 no.1
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    • pp.9-25
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    • 1977
  • As a successive work of the variation studies of natural Pinus densiflora stands, some characteristics of individual trees of the three natural populations selected from the Kwang-won Province, the middle-east part of Korean peninsula, as shown in the location map, were investigated. And the statiscal differences between individuals within population, and between populations were analysed. Twenty trees from each population were selected for this study purpose. Doing this, those trees lagged in growth, usually showing poorer form, were eliminated. The results obtained are summarized as follows: 1. Though the average population ages had the ranage between 50 and 63, the growth of height or diameter was similar. Population No.9 is, however, considered to have better tree forms at glance. Population No.8 showed the heighest value not only in the clear-stem-length ratio. 0.53 but also in the crown-index 0.91. The higher value can be result from those trees having long lateral branches and relatively short crown height, meaning undesirable crown shape. In regard to the fine branchedness and the acuteness of branching angle, the population No.9. is considered to be a better one, whereas there was almost no difference in crown height among populations. 2. Checking the frequency distributions of the ratio of the clear-stem-height to the total height and the crown-indices, some difference between populations are considered. These might be attributed to the previous way of stand mangement which alters the density. 3. In the serration density, the average number of 54 per 1cm needle length, the significant differences exist between individual trees within population but not between populations. A few trees which extremly high serration density were observed. As in serration, so tendencies were in the number of stomata row and resin duct. 4. The population 8 had the resin duct index value of 0.074 as the highest which was twice or triple of the other ones. 5. The patterns of increasing process of the average 10-year-ring-segment were not similar till the 30 years of age, but beyond this, the tendency lines were aggregated. 6. Regading the average summer wood ratio, no diffrence between populations, but in the ranges, i.e. 23 to 30 in population No.8. and 16 to 36 in population No.9., with regad to the specific gravity of wood, there were hardly observed any difference between populations even in the ranges values. As the increase of tree ages, the increase of specific gravity was followed but the increasing patterns were not similar between populations. 7. No significant differences between populations in the average tracheid length and the range were detected. However, the length was increased according to the age increase. The increasing pattern was same between populations.

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A CLINICAL STUDY ON SOFT TISSUE INJURIES OF ORAL & MAXILLOFACIAL REGION (구강 및 악안면 영역의 연조직 손상에 관한 임상적 연구)

  • You, Jun-Young;Kim, Yong-Kwan;Bae, June-soo;Chang, Hyun-Seok
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.19 no.4
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    • pp.407-413
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    • 1997
  • The soft tissue injuries of Oral & Maxillofacial region include abrasion, contusion, simple laceration, laceration of skin with underlying tissue, soft tissue injuries combined with facial bone fracture and involving functional structures such as facial nerve and vessel, orbit, lacrimal duct and salivary gland and so on. The results obtained were as follows ; 1. The age range was 1 to 97, and the highest incidence occured in the 3rd decade(23.4%), followed by the 1st decade(20.2%), 4th decade(18.1%), 4th decade(18.1), and 5th decade(14.3%) 2. The sexual ration was 4 : 1(M : F). 3. The most common cause of facial laceration was a accident(54.5), followed by blow(17.8%), traffic accident(15.9%) and unknown(10.8%). 4. The most frequently occurred site of injury was a forehead(24), followed by oral cavity(16.9%), lip(15%), eyebrow(14.5%), cheek(14%), chin(11.8%), nose(2%), scalp(1.4%) and neck(0.9%). 5. Most of wound size was less than 3cm in length. 6. 28 patients suffered facial bone fracture, representing 7%. 7. The major complications following facial laceration were infection and facial paralysis caused by facial nerve injuries, representing 4.5% and 1.9%.

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A Study of Droplets and Icing Characteristics on Injector in a Liquid Phase LPG Injection Engine (액상분사식 LPG엔진 인젝터의 후적 및 아이싱 특성에 관한 연구)

  • Kim, Chang-Up;Choi, Kyo-Nam;Kang, Kern-Yong;Park, Cheol-Woong
    • Journal of ILASS-Korea
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    • v.12 no.1
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    • pp.38-44
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    • 2007
  • Since the Liquid Phase LPG injection (LPLI) system has Advantages in power generation and emission characteristics compared to the mixer-type fuel-supply system, a variety of studies regarding LPLi system has been conducted and its applications are made in automobile industry. However, the heat extraction due to the evaporation of liquid fuel, causes not only a post-accumulation of fuel but also an icing phenomenon which is a frost of moisture in the air around the nozzle tip. Since there exists a difficulty in the accurate control of air fuel ratio in both fuel supply systems, it can result in poor engine performance and a large amount of harmful emissions. This research examines the characteristics of icing phenomenon and develops anti-icing bushing to prevent an icing on the surface of the injection tip. It was found that n-butane, which has a relatively high boiling point ($-0.5^{\circ}C$), was a main species of post-accumulation. Also the results show that the post-accumulation problem was allevaited the utilization of a large inner to outer bore ratio and smooth surface roughness. In addition, an icing phenomenon and its formation process were found to be mainly affected by the humidity and the temperature of inlet air in an inlet duct. Also, it was observed that an icing phenomenon is lessened using aluminum bushing whose end coincides with the end of fuel injection tip in length.

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Design and Development of Thermoacoustic Rdfrierator : I. Acoustic Analysis of Resonator and Prediction of Energy Conversion (열음향 냉동기의 설계 및 개발 : I. 내부공간의 음향해석 및 에너지 변환 예측)

  • Park, Chul-Min;Ih, Jeong-Guon
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.5
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    • pp.44-52
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    • 1996
  • Acoustical characteristics of internal pipe structures and a loudspeaker of the thermoacoustic refrigerator are analyzed by using the transfer matrix method. The resonator system is dismantled into verious basic acoustic elements, and then linearized transfer matrices are serially combined with the dynamical system of linearized loudspeaker model, that the total system of thermoacoustic refrigerator can be analyzed in terms of frequency characteristics and acoustic field shape. Additionally, by using equations for energy flow through the capillary stack, the temperature distribution over the stack is numerically estimated. After expressing the acoustic work flow, thermoacoustic flow, and energy loss per unit length in a single capillary duct by using the transverse functional variations, overall energy flow rate and energy balance are obtained for the whole capillary stack. The final expression for energy flow through the stack is numerically evaluated by varying physical parameters obtained from the sound field analysis. After confirming good agreements between predicted and experimental results for the interior sound field of a refrigerator model, the thermoacoustic characteristics of Hofler's apparatus is analyzed by the proposed method and it is observed that the results agree well with Hofler's experimental results.

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Clinical and Histopathologic Findings on the Abnormal Liver Function Complicated with Kawasaki Disease (가와사끼 병에 합병된 간기능 이상소견에 대한 임상적 및 병리조직학적 소견)

  • Lee, Sung-Chul;Tchah, Hann;Na, Song-Yi;Kim, Hee-Sup;Park, Ho-Jin;Shin, Mi-Kyeong
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.3 no.1
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    • pp.47-55
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    • 2000
  • Purpose: The aim of this research is to examine the abnormal liver function complicated with Kawasaki disease (KD) and to analyze its clinical characteristics and complications. Methods: Ninty eight cases were diagnosed as having KD, among which thirty four cases had abnormal alanine aminotransferase (ALT) (>30 IU/L). These abnormal ALT cases were evaluated in terms of age and sex distribution, major symptoms, complications, laboratory and histopathologic findings. Results: Male to female ratio was 2.4:1 and most patients (91.2%) were under 5 years of age. Cervical lymphadenopathy was observed in 3 cases (8.8%); and recurred cases were two (5.8%). Average fever duration was 8 days; average length of hospitalization was 9 days; and average recovery period was 13 days. Immediately after admission, positive CRP was observed in 31 cases (91.2%), leukocytosis (> $10,000/mm^3$) in 26 cases (76.0%), thrombocytosis (> $450,000/mm^3$) in 7 cases (20.6%), and anemia (<10 gm/dl) in 7 cases (20.6%), respectively. GB hydrops or cholecystitis were noted in 3 cases (8.8%), abnormal ECG finding in 1 case (2.9%), coronary dilatation or aneurysm in 2 cases (5.9%). Liver biopsy was done in four cases and revealed mild infiltration of lymphocytes on the portal area and mild bile duct proliferations. Conclusion: The abnormal liver function was noted in 34.7% of KD patients, and subsided all within one month. But the liver function test should be checked closely in patients of the abnormal liver function test complicated with KD despite of its good prognosis.

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Clinical outcome of transcatheter closure of patent ductus arteriosus in small children weighing 10 kg or less

  • Park, Young-A;Kim, Nam-Kyun;Park, Su-Jin;Yun, Bong-Sic;Choi, Jae-Young;Sul, Jun-Hee
    • Clinical and Experimental Pediatrics
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    • v.53 no.12
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    • pp.1012-1017
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    • 2010
  • Purpose: Transcatheter closure has become an effective therapy in most patients with patent ductus arteriosus (PDA). However, there are difficulties in transcatheter closure of PDA in small children. We reviewed clinical outcomes of transcatheter closure of PDA in children weighing less than 10 kg in a single center. Methods: Between January 2003 and December 2009, 314 patients with PDA underwent transcatheter closure in our institute. Among them, 115 weighed less than 10 kg. All of these patients underwent transcatheter closure of PDA using either COOK Detachable $Coil^{(R)}$, PFM Nit-$Occlud^{(R)}$, or Amplatzer duct $occluder^{(R)}$. A retrospective review of the treatment results and complications was performed. Results: The mean age of patients was $9.1{\pm}5.9$ months (median, 8 months), and mean weight was $7.6{\pm}1.8kg$ (median, 7.8 kg). The mean diameter of PDA was $3.2{\pm}1.4mm$ (median, 3 mm). Complete occlusion occurred in 113 patients (98%). One patient was sent to surgery because of a failed attempt at device closure, and another patient had a small residual shunt after device placement. The average mean length of hospital stay was $3.0{\pm}3.3$ days, and mean follow-up duration was $21.0{\pm}19.6$ months. There were no major complications in any of the patients. Conclusion: Transcatheter closure of PDA is considered safe and efficacious in infants weighing less than 10 kg. With sufficient experience and further effort, transcatheter closure of PDA can be accepted as the gold standard of treatment for this group of patients.

Flow and Heat Transfer Characteristics in a Separated Flow over Backward-facing Step and Cavity Controlled by Acoustic Excitation (음향여기에 의한 2차원 후방계단과 공동 내의 유동 및 열전달 특성 변화)

  • Jo, Hyeong-Hui;Gang, Seung-Gu;Lee, Dong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.9
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    • pp.1253-1262
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    • 2001
  • Experimental study is conducted to investigate the heat/mass transfer and flow characteristics for the flow over backward-facing step and cavities. A naphthalene sublimation method has been employed to measure the mass transfer coefficients on the duct wall and LDV system has been used to obtain mean velocity profiles and turbulence intensities. Reynolds number based on the step height and free stream velocity is 20,000 and St numbers of acoustic excitations given to separated flow are 0.2 to 0.4. The spectra of streamwise velocity fluctuation show a sharp peak forcing frequency for an acoustically excited flow. The results reveal that the vortex pairing and overall turbulence level are enhanced by the acoustic excitation and a significant decrease in the reattachment length and the increased turbulence intensity are observed with the excitation. A certain acoustic excitation increases considerably the heat/mass transfer coefficient at the reattachment point and in the recirculation region. For the cavities, heat/mass transfer is enhanced by the acoustic excitation due to the elevated turbulence intensity. For the 10H cavity, the flow pattern is significantly changed with the acoustic excitation. However, for the 5H cavity, the acoustic excitation has little effect on the flow pattern in the cavity.

A Preliminary Study on the Construction or the AM/FM System for a Univesity (대학 시설물관리시스템 구축에 관한 기초적 연구)

  • 안기원;이효성;신석효
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.15 no.2
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    • pp.277-286
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    • 1997
  • The purpose of this study is to construct the AM/FM system for a university. The sample area used in this study is the Gyeongsang National University in Chinju City, Korea. The layout maps, which scale are 1/1200, 1/3000 and 1/5000, a map of planning of common duct, which scale is 1/1200, and the facility maps which scale is 1/200 were used for input of spatial data. The year of pipe buried, materials of pipe, pipe diameter, length of pipe, depth of pipe buried and slope of pipe buried were purpose of efficient data searching, analyzing, and processing. It was revealed that rapid providing of facility informations and efficient facility management are possible using the constructed the AM/FM system for a university.

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