• Title/Summary/Keyword: growth increments

Search Result 103, Processing Time 0.032 seconds

Effects of Microclimate of Different Site Types on Tree Growth in Natural Deciduous Forest (입지유형별 미기후가 천연 활엽수림의 임목 생장에 미치는 영향)

  • Shin, Man-Yong;Chung, Sang-Young;Han, Won-Sung;Lee, Don-Koo
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.10 no.1
    • /
    • pp.9-16
    • /
    • 2008
  • In this study we investigated the effects of the microclimatic conditions on tree growth in different site types for natural deciduous forests in Korea. First, we classified all the sites into 36 types according to their aspect (east, west, south, and north), elevation (higher than 1,000 m, 700$\sim$1,000 m, and lower than 700 m), and topographical conditions (ridge, slope, and valley). For each site type, we measured diameter growth with increment borer, and then estimated periodic annual increment of diameter, height and volume. We applied a topoclimatological technique for estimating microclimatic conditions, and produced monthly climatic estimates from which 17 weather variables (including indices of warmth, coldness, and aridity) were computed for each site type. The periodic annual increments of diameter, height, and volume were then correlated by regression analysis with those weather variables to examine effects of microclimate on tree growth by site type. We found that the correlation of diameter growth by site type was significantly correlated with most weather variables except daily photoperiod. Water condition was the most important factor for the height growth. For volume growth, on the other hand, the conditions such as relatively high temperature and low humidity provided favorable environment. Our regression analysis shows that aridity index is a good predictor for tree growth including diameter, height and volume increments.

A LONGITUDINAL ROENTGENO-CEPHALOMETRIC STUDY ON THE CRANIOFACIAL DEPTH AND HEIGHT BY COBEN'S METHOD (Coben법에 의한 한국 아동의 두개안면골의 성장 변화에 관한 누년적 연구)

  • Ahn, Hyo-il;Ryu, Young-Kyu
    • The korean journal of orthodontics
    • /
    • v.15 no.1
    • /
    • pp.23-42
    • /
    • 1985
  • The morphology and growth changes of the Craniofacial Complex are important in orthodontics and cephalometrics for analysis and evaluation of facial bone growth are widely used. The author analyzed the data using lateral cephalometric roentgenogram of 75 Korean male and 50 Korean females age of 6 to 10 with normal occlusion to provide informations-relative rates of facial bone growth of Korean which is to be contributed in Korean standard. The results were as follows: 1. Means, standard deviation and coefficient of variation of Korean children were obtained. 2. The item which showed significent difference between male and female was craniofacial height in absolute dimension. 9. No difference of sex was showed in increment of craniofacial height and depth. 4. Among the craniofacial depth increments, the lower facial depth dimension increased most, midfacial depth dimension increased less, and cranial depth dimension increased the least. 5. The horizontal body of mandible showed rapid growing tendency more than did the ascending ramus.

  • PDF

A STUDY ON THE ADAPTATION OF HEAD POSTURE AFTER ACTIVATOR THERAPY IN FUNCTIONAL CLASS III MALOCCLUSION PATIENTS (Angle씨 III급 부정교합자의 Activator치료 전후 head posture변화에 관한 연구)

  • Seo, Hyung-Sik;Cha, Kyung-Suk
    • The korean journal of orthodontics
    • /
    • v.24 no.2
    • /
    • pp.319-329
    • /
    • 1994
  • This study was carried out to research the adaptation patterns of head posture after activator therapy in functional class III malocclusion patients. For this purpose, 29 functional class III malocclusion patients, from the ages of 8 to 13 years old, were used. 1, Increse in capacity of oral cavity capacity were found in all the samples, but craniocervical angulation were varied into incresed group and decreased group after activator therapy. 2. Head posture exhibited the compensatory adaptation in the relative growth increments of the vertical dimension, ALFH and PLFH. 1) A group with more PLFH and less sagittal angle showed relatively small growth increment in PLFH during the treatment period, thus craniocervical angulation was increased. 2) A group with less PLFH and more sagittal angle showed relatively great growth incrmenet in PLFH during the treatment period, thus craniocervical angulation was decreased.

  • PDF

Age and Growth of Anchovy (Engraulis japonica) Juvenile in the Coastal Waters of Chonnam, Korea (전남 연안해역 멸치(Engraulis japonica)의 연령과 초기 성장)

  • CHA Seong Sig
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.23 no.5
    • /
    • pp.385-393
    • /
    • 1990
  • Age and growth in length of anchovy juveniles were analysed from the samples collected from the coastal waters of Chonnam, Korea, in 1988 and 1989. Ages in days were determined by counting growth increments in otolith from 248 individuals. Growth in length versus age in days was well represented by Gompertz curve: $$L =5.76{\times}E xp(1.66 \times(1- E xp(-0.44\;t)))$$, or $$L=3.7{\times}E xp(1.99\times(1-E xp(-0.0614\;t)))$$. The mean growth rate was 0.38 mm/day from 20 days to 40 days. Growth rate was maximum at 10 days, and then decreased gradually. The growth of anchovy juvenile were nearly constant inspite of the sampling dates or stations.

  • PDF

AN EXPERIMENTAL STUDY OF THE EFFECT OF FLUORIDE COMPOUNDS ON THE GROWTH OF STREPTOCOCCUS MUTANS (불소화합물이 Streptococcus mutans의 증식에 미치는 영향에 관한 실험적 연구)

  • In, In -Sook;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.11 no.1
    • /
    • pp.151-157
    • /
    • 1984
  • The purpose of this study was to compare the growth-inhibiting effect of sodium fluoride and stannous fluoride on a cariogenic strain of Streptococcus mutans exposed to the different concentration of $SnF_2$ and NaF The result were as follows: 1. The growth rate of the Streptococcus mutans was unaffected by 75 ppmF, slowed by 150 ppmF, and immediately arrested by 300 or 600 ppmF where increments of NaF were added to actively growing 12-hour broth culture. 2. $SnF_2$ slowed the growth rate at 75 ppmF, was to bactericidal initially at 150 and 300 ppmF, and was to totally bactercidal at 600 ppmF. 3. $SnF_2$ has been shown to be more effective than NaF in inhibiting the growth activity of Streptococcus mutans. 4. The inhibitory effect of fluoride compounds on the growth of Streptococcus mutans was increased in the decreased pH at concentration of 600 ppmF.

  • PDF

Studies on the Analysis of Stand Structure Korean Red Pine (Pinus densiflora) (소나무림(林)의 임분구조(林分構造) 해석(解析)에 관(關)한 연구(硏究))

  • Yun, Jong Wha;Kim, Ju Cheon
    • Journal of Korean Society of Forest Science
    • /
    • v.83 no.2
    • /
    • pp.254-261
    • /
    • 1994
  • This study was conducted to investigate and interpret the stand structure of Korean Red pine (Pinus densiflora) stands in Kangwon province, so as to provide basics information for effective forest management. The results obtained in this study were as follows : 1. Number of trees distribution for each diameter class have left nonsymmetrical in Gosung districts, but symmetrical distribution in Pyungchang districts. 2. Height curve for D.B.H. Distribution becames liner shape in Pyungchang districts that more higher than Gosung districts. 3. Stand volume and number of trees per ha in Pyungchang districts are higher than Gosung districts. 4. D.B.H. growth increments during recent 5 years at large D.B.H. class has much lager than low D.B.H. class. 5. Total growth increments of D.B.H., height and volume in Pyungchang districts are or the higher than Gosung districts overtimes 15 years later.

  • PDF

Spawning Time and Early Growth of Pacific Cod (Gadus macrocephalus) in Jinhae Bay, Korea (진해만 대구의 부화일 및 초기 성장에 관한 연구)

  • Gwak, Woo-Seok;Choi, Byung-Eon;Lee, So-Gwang
    • Korean Journal of Ichthyology
    • /
    • v.24 no.2
    • /
    • pp.110-117
    • /
    • 2012
  • Hatching date and early growth of Pacific cod Gadus macrocephalus were estimated by examination of otolith microstructure of Pacific cod juveniles collected in Jinhae Bay of Korea from May to June, 2008. Water temperature during the main spawning time ranged from 7 to $9^{\circ}C$ according to the geographic distribution of temperature measured from November to May between 2006 and 2009. The spawners were collected from December to February between 2006 and 2008, and the gonadosomatic index of spawners was larger in females than in males, showing a peak in January. Total length of juveniles ranged from 37.5 to 94.9 mm ($63.2{\pm}11.0mm$; mean${\pm}$SD). The number of daily growth increments in juvenile otoliths were on average $102{\pm}15$ in May 17 samples, $119{\pm}16$ in May 29 ones and $116{\pm}18$ in June 3 ones. Hatching dates estimated from the number of daily growth increments ranged from late December to mid-March, showing the peak between late January and mid-February. Daily growth in total length (TL, mm) can be adjusted to the Gompertz curve: $TL_t=123.2{\exp}\{-{\exp}[-0.0165(t-81.8)]\}$ ($r^2$=0.93, n=273).

An Analysis for The Ductile Crack Growth (연성 균열성장의 해석)

  • 구인회
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.14 no.1
    • /
    • pp.103-111
    • /
    • 1990
  • This paper presents a methodology for predicting stable crack growth and instability of a cracked body under monotonically increasing load. It is based on a model that incremental crack extensions and load increments after fracture initiation occur by turns in sequence and the criterion that the crack grows by an incremebt .delta.a when the opening displacement at the current crack tip increases by a critical value V$_{c}$. It is shown that the value I$_{c}$ = V$_{c}$/ .delta. a is a material constant characterizing ductile crack growth resistance. Along with the fracture initiation toughness value, the constant is used for the calculation of the loads against crack extensions by adding up each increment. The specimen failure is defined to occur when the necessary load increment for crack extension is zero or when the limit load in the current ligament is reached. The predicted failure loads are in good agreement with the avaliable experimental failure loads for the compact and center-cracked tension specimens of 7075-T651, 2024-T351 aluminum alloys and 304 stainless steel.steel.

Seasonality of shellfish collection determined by growth-line analysis of the hard clam, Meretrix petechialis (Lamarck) recovered from the Eurwang-dong Shell Midden, Incheon, Korea (인천 을왕동 패총 출토 말백합 Meretrix petechialis (Lamarck) 의 성장선 분석을 이용한 패류 채집의 계절성 연구)

  • An, Deog-im;Ryu, Dong-Ki
    • The Korean Journal of Malacology
    • /
    • v.32 no.1
    • /
    • pp.25-30
    • /
    • 2016
  • Growth-line analysis was carried out on 80 hard clam (Meretrix petechialis) from the Neolithic Age Eurwang-dong Shell Midden, Incheon, Korea, to determine the seasonality of shellfish collection and site occupation. Growth increments and the marginal index (MI) of the specimens were examined. And then the marginal index was compared to the monthly MI of modern specimens under the assumption that the growth pattern was the same as it is today. MI of the archaeological specimens ranged from 0.12 to 1.55 and was divided into four categories: < 0.63, spring; 0.63-0.76, summer; 0.76-0.89, fall; $${\geq}_-0.89$$, winter collection. As a result, 57 specimens (71.25%) of 80 specimens represented spring, 8 (10.0%) summer, 3 (3.75%) fall and 12 (15.0%) winter collection. The result indicates that shellfish could be collected year-round at the site with an emphasis on spring. Based on the size distribution of shells and the content of the midden, however, it seems that the midden site was not occupied permanently throughout the year but was used repeatedly but temporally for shellfish gathering and processing.

THE RETROSPECTIVE STUDY ON THE RESPONSE TO THE CHINCAP THERAPY IN SKELETAL CLASS III CHILDREN (골격성 III급 부정교합환자의 이모장치에 대한 반응성 및 치료효과에 관한 연구)

  • Kim, Byoung-Ho;Yang, Won-Sik
    • The korean journal of orthodontics
    • /
    • v.24 no.4 s.47
    • /
    • pp.799-817
    • /
    • 1994
  • The purpose of this study was to evaluate the initial skeletal pattern and growth change of whom had responsed well to chincap therapy. 93 patients seleted for this study were in mixed dentition and treated with chincap for more than 2 years. And 54 subjects were selected from these total samples and classified into two groups by the improvement of four measurements : ANB difference, APDI, Wits appraisal, and AF-BF. One was good response group which consisted of 26 children and the other was poor response group with 19 patients. Various measures of the craniofacial structure in the initial lateral cephalograms and the annual increments were calculated and analyzed by comparing two groups with t-test. The results were as follows : 1. Good response group had more horizontal growth pattern in initial stage of treatment than poor response group, and the contributing factors of this result were anterior posterior facial height ratio, gonial angle, lower genial angle and SN-mandibular plane angle. 2. The maxilla was positioned more anteriorly in good response group. 3. The amounts of vertical growth of maxilla was smaller but the horizontal growth of maxilla was larger in good response group. 4. The mandible rotated more infero-posteriorly in good response group. 5. The good response group had more vertical growth pattern of mandibular condyle.

  • PDF