• Title/Summary/Keyword: Estimating

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Newly Revised Lung Cancer Staging System and Survival in Non-Small Cell Lung Cancer Patients (새로 개정된 폐암 병기 판정에 따른 비소세포폐암 환자의 생존 분석)

  • Kim, Byeong-Cheol;Moon, Doo-Seop;Yoon, Su-Mi;Yang, Seok-Chul;Yoon, Ho-Yoo;Shin, Dong-Ho;Park, Sung-Soo;Lee, Jung-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.3
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    • pp.339-346
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    • 1999
  • Background : Non-small cell lung carcinoma is a common tumor with a poor prognosis. Of all malignancies, it is the main cause of death for male and female patients in the Western world. Resection remains the most effective treatment when feasible. Accurate description and classification of the extent of cancer growth are important in planning treatment, estimating prognosis, evaluating end results of therapy, and exchanging information on human cancer research. Until effective systemic therapy is available for non-small cell lung cancer, development of new treatment strategies depends on knowledge of the end results achieved for carefully staged groups of patients in the lung cancer populations. For these reasons, we investigated the survival rate in radically resected non-small cell lung cancer patients by newly revised staging system adopted by the American Joint Committee on Cancer and the Union Internationale Contre le Cancer. Methods: Clinical, surgical-pathologic and follow-up informations on 84 consecutive, previously untreated, patients who received their primary treatment for non-small cell lung cancer were investigated. Staging definitions for the T(primary tumor), N(reginal lymph node), and M(distant metastasis) components were according to the International Staging System for Lung Cancer. Death from any causes was the primary target of the evaluation. Results: The median survival rates were as follows; stage I ;79.1 months, stage II ;47.3 months, stage IIIa; 22.7 months, stage IIIb; 16.1 months, and stage IV;15.2 months versus newly revised stage Ia;58.5 months, stage I b;76.0 months, stage IIa; not available, stage IIb;43.0 months, stage IIIa;22.5 months, stage IIIb; 16.1 months, and stage IV;15.2 months. The survival rates were not significantly different between old and newly revised staging system. Cumulative percent survival at 36months after treatment was 100% in stage Ia, 80% in stage Ib, not available in stage IIa, 26 % in stage IIb, and 21 % in stage m a respectively. Conclusions: Although these data were not significantly different statistically, the newly revised lung cancer staging system might be more promising for the accurate evaluation of the prognosis in the non-small cell lung caner patients.

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Biomass Expansion Factors for Pinus densiflora in Relation to Ecotype and Stand Age (소나무의 생태형과 임령에 따른 물질 현존량 확장계수)

  • Park, In Hyeop;Park, Min Su;Lee, Kyeong Hak;Son, Yeong Mo;Seo, Jeong Ho;Son, Yowhan;Lee, Young Jin
    • Journal of Korean Society of Forest Science
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    • v.94 no.6
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    • pp.441-445
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    • 2005
  • Researches on estimating national-scaled forest biomass are being carried out to quantify the carbon stock of forests with the Kyoto Protocol. In general, estimates of national-scaled forest biomass are based on forest inventory data which provides estimates of forest area, stem volume, and growth of stem by age classes. Estimates of forest biomass are, however, obtained by converting stem volumes to dry weight with stem density and thereafter to whole tree biomass with biomass expansion factors (ratios of whole tree dry weight to stem dry weight). Pinus densiflora is widely distributed and one of the most economically important timber species in Korea. The species are largely grouped into two ecotypes of Geumgang and Jungbu. Stems of Geumgang type trees are straight and high compared to those of Jungbu type trees. The objective of this study was to determine and compare stem density and biomass expansion factors fore two ecotypes of Pinus densiflora according to stand age. Stem density of both ecotypes of Pinus densora increased and biomass expansion factors of them decreased with increasing tree age. In he same age class, stem density and biomass expansion factor of Geungang type Pinus densiflora were lower than those of Jungbu type Pinus densiflora. There were statistically significant differences in stem density and biomass expansion factors between Geumgang type and Jungbu type Pinus densiflora in 0-20-year-old stands and 40-60-year-old stands. Our results suggested that the reliability of the national forest biomass inventory could be improved by applying the ecotype- and age-dependent stem density and biomass expansion factors.

Characteristics of Soil Erosion on the Forest Fired Sites by Using Rainfall Simulator (인공강우장치를 이용한 산불발생지의 토양침식 특성에 관한 연구)

  • Lee, Heon Ho;Joo, Jae Duk
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.649-656
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    • 2006
  • The purpose of study is to measure soil erosion quantity for elapsed four years from the fire on forest fired sites of Dong-gu, Daegu. This study was conducted to investigate the characteristics of soil erosion by fire occurrence influencing on the soil erosion were. Also analysis result follows that the relations between soil erosion quantity and rainfall intensity, the slope and elapsed year. The results analysed were as follows: 1. Soil erosion by year of occurrence of forest fire was increased 1.9 to 5.7 times as rainfall intensity was increased by 30 m/hr, and 1.4 to 14.2% as degree of slope was increased by $10^{\circ}$. 2. In the first year of forest fire occurrence, soil erosion was fairly heavy for 10 minutes of initial rainfall of which rainfall intensity was 80 m/hr and degree of slope was $30^{\circ}$. The amount of soil erosion was gradually reduced as elapsed time. From two years after fire, the amount of soil erosion by rainfall intensity and degree of slope was nearly constant. 3. The amount of soil erosion by rainfall intensity and slope in accordance with elapsed time after fire was reduced 28.9 to 94.1% in three years after occurrence of forest fire as compared to the first year of fire. Soil erosion was fairly heavy by rainfall intensity and slope in the first year of fire, but it was gradually reduced from two years after fire. 4. In the analysis on influences of each factors on the amount of soil erosion on forest fired sites, the amount of soil erosion was significant differences in major impacts of each rainfall intensity, degree of slope and elapsed year after fire and interaction of rainfall intensity${\times}$degree of slope and rainfall intensity${\times}$elapsed year after fire, but no differences were observed in interaction of degree of slope${\times}$elapsed year after fire and rainfall intensity${\times}$degree of slope${\times}$elapsed year after fire. Rainfall intensity was the most affecting factor on the amount of soil erosion and followed by degree of slope and elapsed year after fire. 5. For correlation between soil erosion and affecting three factors, soil erosion showed significant positive relation with rainfall intensity and degree of slope at I % level, and significant negative relation with elapsed year after fire at 1 % level. 6. As a result of regression of affecting three factors on soil erosion. rainfall intensity was most significant impact factor in explaining the amount of soil erosion on forest fired sites, followed by degree of slope and elapsed year after forest fire. 7. The formula for estimating soil erosion using rainfall intensity, degree of slope and elapsed year after forest fire occurrence was made. S.E = 0.092R.I + 0.211D.S - 0.942E.Y(S.E : Soil erosion, R.I : Rainfall intensity, D.S : Degree of slope, E.Y : Elapsed year after forest fire occurrence)

Growth and Physiological Responses of 1-Year-Old Containerized Seedlings of Quercus myrsinaefolia by Shading Treatment (피음처리에 따른 가시나무 1년생 용기묘의 생장과 생리적 반응)

  • Song, Ki-Sun;Sung, Hwan-In;Cha, Young-Geun;Kim, Jong-Jin
    • Journal of Bio-Environment Control
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    • v.20 no.4
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    • pp.373-381
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    • 2011
  • This study was carried out to investigate the growth and physiological responses to shading treatment of 1-year-old containerized seedling of Quercus myrsinaefolia. Experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Height and root collar diameter growth were high in the seedlings under both 35% and 55% shading. Regardless of shading level, root collar diameter growth lasted for more than 4 weeks compared to height growth. Highest H/D ratio was observed in the seedlings under 35% shading as 4.31, and the lowest ratio was 3.63 under 75% shading. It was found that seedlings under 55% shading showed highest dry mass production, which was followed in seedlings under 35% shading. In case of leaf dry weight ratio (LWR) after shading treatment, the highest value was 0.53 under 55% shading, and followed in seedlings under 35% shading as 0.52. But root dry weight ratio (RWR) was highest as 0.36 under 75% shading (highest level of shading). In terms of shading treatment, it was found that the higher level of shading had a tendency toward the higher content of chlorophyll a and the higher total chlorophyll content in the leaves of Quercus myrsinaefolia, but there was no significant difference in the content of chlorophyll b depending on the level of shading. It was found that high photosynthesis and transpiration rate were more correlated with high level of shading than full sunlight, but the rates of seedlings had a tendency to be higher under 35% and 55% shading than under 75% shading. The results on growth and physiological responses to different shading levels of 1-year-old containerized seedlings of Quercus myrsinaefolia could be useful in setting up the optimum light intensity for growth, and in estimating the shade tolerance of the species.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2013 (설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.12
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    • pp.605-619
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    • 2014
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 (설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.7
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

Cytotaxonomic study of Korean Euphorbia L. (Euphorbiaceae) (한국산 대극속(Euphorbia L., Euphorbiaceae)의 세포분류학적 연구)

  • Chung, Gyu Young;Oh, Byoung-Un;Park, Ki-Ryong;Kim, Joo-Hwan;Kim, Mi Suk;Nam, Gi-Heum;Jang, Chang-Gee
    • Korean Journal of Plant Taxonomy
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    • v.33 no.3
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    • pp.279-293
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    • 2003
  • Somatic chromosomes about 13 taxa of Korean Euphorbia L. was investigated to estimate its taxonomic significance. Somatic chromosome numbers of treated taxa were 2n= 12, 20, 22, 28, 40, 42, 56, therefore basic chromosome numbers of those were x=6, 7, 10, 11. The chromosome numbers of E. pallasii Turcz. (2n=20), E. hylonoma Hand.-Mazz (2n=20.), E. fauriei H. L$\acute{e}$v. & Vaniot ex H. L$\acute{e}$v (2n=28) and E. jolkini Boiss. (2n=28) were determined for the first time in this study. The chromosome numbers of four taxa were same as previous ones; E. sieboldiana Moor. & Decne. (2n=20), E. ebracteolata Hayata (2n=20), E. humifusa Willd. ex Schlecht. (2n=22). But those of six taxa were different; E. esula L (2n= 16, 20, 60, 64 vs 2n=20), E. helioscopia L. (2n=12, 42 vs 2n=42), E. lucorum Rupr. (2n=28, 40 vs 2n=56), E. pekinensis Rupr. in Maxim. (2n=24 vs 2n=28, 56), E. maculata L. (2n=28, 42 vs 2n=12), E. supina Raf. (n=7 vs 2n=40). E. ebracteolata, E. pallasii and E. hylonoma were distingushcd from the other taxa by the chromosome numbers, size and satellites, E. maculata, E. humifusa, E. supina had the different basic and somatic chromosome numbers in spite of the similar morphological. anatomical and palynological chracters. The chromosomal character of Korean Euphorbia was supported the Ma and Hu's systems, and as above results, it was found to be a good character in delimiting above sections and estimating relationships for some species.

Establishment of the Text Method for Evaluating the Fideld Resistance of Rice Varieties to Rice leaf Blight (벼 흰잎마름병 포장저항성 검정방법 체계 확립+)

  • Lee, Du-Gu;Sim, Jae-Seong
    • The Journal of Natural Sciences
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    • v.7
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    • pp.91-101
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    • 1995
  • To establish the simple and practical test method of estimating resistance of rice varieties against rice leafblight, trials were made to correlate among the four test methods such as true resistance test,secondaryinfection test, secondary epidemic test and field test. The results obtained through the experiment on 25 ricevarieties and 3 pathogenic isolates designated to HB9O11, HB9022 and HB9033 can be summarized asfollows. 1 .Based on the results of true resistance test, 25 rice varieties can be classified into four groups:1 )Samgang variety group ;resistant to HB9011, 13 varieties, 2)Pungsan variety group ; resistant to HB9011 and HB9022, 5 varieties, 3)Samgang variety group ; resistant to all three isolates, 2 varieties, 4)Unbongvariety group: sensitive to all three isolates, 12 varieties. 2. The responses of rice varieties to isolates showed some discrepancies among on the test methods. These examples were found in 3 varieties including Yeongdeog varieties to HB9011, 3 varieties including Taebaeg variety to HB9022 and Taebaek vaieties to HB9033. 3. Correlation coefficiences between the secondary infection test and the secondary epidemic test for HB9011, HB9022 and HB9033 were 0.972, 0.894 and 0.919, respectively. It suggests that the two methods are not significantly different so that one of the two methods are not significantly different so that one of the two methods can be omitted from resistant test without affecting the result. 4. Between the true resistance test and the field test at the disease common area, there were no significant correlations. Unbong, Chucheong and Yeongdeog varieties are appeared as resistant varieties in the true resistant test, but their responses in the field test were different and appeared as sensitive varieties. 5. The disease index was used to express theresults from four test methods. The disease index was calculated as the sum of each numerical values of theresults from the four test methods by giving the same weights(0 to 25)to each test method. If the disease index for certain variety is less than 15, then the variety is considered to be resistant. 4 varieties such as Seohae, Hwajin, Yeongdeog and Pungsan varieties-disease indices were less than 15 were selected as field resistance varieties.

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Estimating the Parameters of Pollen Flow and Mating System in Pinus densiflora Population in Buan, South Korea, Using Microsatellite Markers (Microsatellite 표지를 이용한 부안지역 소나무 집단의 화분 유동과 교배양식 추정)

  • Kim, Young Mi;Hong, Kyung Nak;Park, Yu Jin;Hong, Yong Pyo;Park, Jae In
    • Korean Journal of Plant Resources
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    • v.28 no.1
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    • pp.101-110
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    • 2015
  • Parameters of mating system and pollen flow of a Pinus densiflora population in Buan, South Korea, were estimated using seven nuclear microsatellite markers. The expected heterozygosity ($H_e$) was 0.614 in mother trees and 0.624 in seeds. Fixation index (F) was 0.018 and 0.087 in each generation. There was no significant genetic difference between the generations (P > 0.05). From MLTR, the outcrossing rate ($t_m$), the biparental inbreeding ($t_m-t_s$), and the correlation of paternity ($r_p$) were 0.967, 0.057, and 0.012, respectively. tm was larger but $t_m-t_s$ and $r_p$ were smaller than those of allozyme markers in Pinus densiflora. These values were similar to those of microsatellite markers in other pine species. The optimal pollen dispersal model from TwoGener was the normal dispersal model with the effective density of 220 trees/ha and its level of genetic differentiation in pollen pool structure (${\Phi}_{ft}$) was 0.021. The average radial distance of pollen flow (${\delta}$) was calculated as 11.42 m, but no correlation between the pairwise-${\Phi}_{ft}$ and the geographical distance among mother trees was at Mantel test (r = -0.141, P > 0.05). Although the effective pollen dispersal in the population seems to be restricted, the amount of genetic variation might be maintained in each generation without a loss of genetic diversity. It might be because the genetic diversity in pollen pool was high but the genetic difference between pollen donors was small under the complete random mating condition in the Pinus densiflora population in Buan.

A Review of Statistical Methods in the Korean Journal of Orthodontics and the American Journal of Orthodontics and Dentofacial Orthopedics (대한치과교정학회지(KJO)와 미국교정학회지(AJODO)에서 사용된 통계기법의 비교분석 및 고찰(1999-2003))

  • Lim, Hoi-Jeong
    • The korean journal of orthodontics
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    • v.34 no.5 s.106
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    • pp.371-379
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    • 2004
  • The purpose of this study was to investigate the changes and types of statistical methods used in the Korean Journal of Orthodontics (KJO) and the American Journal of Orthodontics and Dentofacial Orthopedics (AJODO) from )999 to 2003. The frequency of use, transitions, assumption check of statistical methods and types of advanced statistical methods were examined from each journal. The study consisted of 247 articles published in the KJO and randomly chosen 50 articles per year which were original articles and used statistical methods T-test, analysis of variance(ANOVA), correlation analysis, nonparametric analysis. regression analysis chi-square test. factor analysis, were the order of statistical methods most frequently used in the KJO, while t-test. ANOVA, nonparametric analysis, correlation analysis, regression analysis, chi-square test. factor analysis. were the order of statistical methods used in the AJODO The changes of statistical methods observed in the KJO were not significant $(X^2=17.4\;p=0.5881)$ but the changes observed in the AJODO was seen to be significant $(x^2=42.4,\;p=0.0397)$ Some of the studies examined had overlooked the assumptions of the statistical methods employed. Data investigation such as outlier should be performed before analysis and alternative statistical approaches are applied for a small sample size. Types of advanced statistical methods were factor analysis and discriminant analysis in the KJO and Intention-To-Treat (ITT) analysis in clinical trials through multi-center, survival analysis and Generalized Estimating Equations (GEE) in the AJODO. Appropriate analysis approaches and interpretations should be applied for the correlated and repeated measurements of the orthodontic data set.