• Korean Journal of Environment and Ecology
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• v.27 no.4
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• pp.462-472
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• 2013

This study was carried out to provide a basic data for preservation of Pinus desiflora forest as cultural landscape forest by analyzing characteristics of plant community of P. desiflora forest in Geumjeongsan(mountatin) in Busan city. In order to analyze plant community of P. densiflora in Geumjeongsan, we set up 10 study plots inside and 8 plots outside of Geumjeongsansung(mountain fortress, hereinafter 'Sansung')(unit area: $400m^2$), a total of 18 plots. TWINSPAN analysis divided these 18 study plots into 6 communities which are Querqus serrata-P. desiflora community, P. desiflora community, P. desiflora-Q. serrata community, P. thunbergii-P. densiflora community, P. densiflora-P. thubergii-Q. acutissima community, and P. densiflora-Platycarya strobilacea community. Importance Percentage (I.P.) of each area and DBH class distribution of main species showed that P. densiflora community would succeed to Q. serrata community or C. tschonoskii community. Analysis on tree age found out that communities in the Sansung were 32~37 years old and those outside the Sansung were 44~57 years old. Shannon's species diversity index ranged from 0.4826 to 1.2499. Regarding correlation between species, P. densiflora had negative correlation with Styrax japonica. Based on abovementioned result we expected ecological succession from P. densiflora community to Q. serrata community inside of the Sansung. Outside the Sansung, succession from P. densiflora-P. thunbergii community to C. tschonoskii-Q. serrata community was expected. In order to manage P. densiflora forest as cultural landscape forest, Q. spp in the understory and shrub layer and deciduous broad-leaved arboreal trees should be managed. Tree crown management of deciduous broad-leaved trees in competition with P. desiflora, is also required.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.349-356
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• 2007

Three active components (Z8-12:Ac, E8-12:Ac, and Z8-12:OH) are known in sex pheromone of the oriental fruit moth, Grapholita molesta, and have been commercially available to apply for population monitoring and mating disruption. However, there have been variation among commercial products in pheromone composition and amount impregnated in each pheromone releaser. This study was performed to optimize factors influencing on pheromone monitoring of G. molesta by analyzing pheromone composition/amount, effective period of releaser, and trap type/placement in apple trees. High purity of Z8-12:Ac component was effective to attract males, in which 96% or more of cis acetate isomer component appeared to be optimal composition. Pheromone amounts ($0.01-1\;{\mu}g$) impregnated in each rubber dispenser did not give significant effect on monitoring during 90 days from June to August. "Delta" trap was much more efficient than "cone" trap to collect males. Trap installation was another factor, in which placing traps at canopy level was much efficient than at trunk or ground levels. Pheromone trap monitoring with these optimal factors indicated three to four adult peaks from June to September in addition to high overwintering population from April to May in pesticide-applied orchards in Andong, Korea.

• The Journal of Fisheries Business Administration
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• v.30 no.2
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• pp.91-105
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• 1999

본 연구는 필자가 미국 Oregon 주의 수산업사를 조사하던 중 1940년대부터 시작된 미국으로 이민 한 중국인들이 미국 서부 수산업에 미친 영향이 거대하다는 것을 발견하고, 이에 관련된 문헌을 찾아 최초 미국 서부(특히, California 주)에 이민하기 시작했던 중국 이민자들이 미국에서 수산업 활동을 시작한 배경과 그에 따른 영향 등을 살펴본 것이다. 중국인이 미국에 이민하기 시작한 배경은 두 가지가 있다. 하나는 국내적인 요인으로서 중국에서의 경제적 빈곤과 정치적 핍박이었고, 다른 하나는 국외적인 요인으로서 금캐기가 가능하다는 소식 등 미국 생활에 대한 동경이었다. 중국인의 미국 이민사에서 독특한 점의 하나는 중국 남부지 방에 위치한 광동성 지방민들이 절대적인 비중(90% 이상)을 차지하고 있다는 것이다. 가장 큰 이유는 광동성은 일찌기 외국문물이 드나드는 곳이어서 인근 광동성 지방민들은 다른 지방민보다 외국소식을 쉽게 접할 수 있었기 때 문이었다. 미국에 도착한 광동성 지방민들은 쉽게 직업을 구할수 없는 처지이 되자 그들이 익숙하게 알고 있는 바다생활에 뛰어들었고, 마침내는 미국 서부에서 진취적인 어업인이 되었다. 따라서 서부에서 최초의 상업적 어업인이 되었으며, 미국 서부에서 시작한 중국인의 수산업은 점차 다른 주로 퍼져 나갔다는 기록은 중국인이 미국 전역에서 최초의 상업적 어업인이었음을 알게 한다. 최초의 중국인 어촌은 1854년 San Francisco의 Rincon Point에 세워졌으며, 25척의 어선과 150여명의 주민이 살았다. 그들이 사용한 어구ㆍ어업은 통발, 정치망, 선망, 낚시, 연승 등이었으며, 중국풍의 어선과 어구를 직접 만들어 새우, 철갑상어, 대구, 우럭, 넙치, 게, 가재, 전복 등을 어획했다. 1888년에는 San Francisco 전역에 20개의 어촌이 형성되었고, 2천여명의 어업종사자가 있었다. 1900년부터는 점차 그 수가 줄기 시작하였다. 가장 크고 오래 지속된 어업은 새우어업은 1860년대부터 1940년 중반까지 계속되었으며, 이 어업에 의해 새우가 인근 지역의 보편적인 식품으로 자리하게 되었다. 인디언에 의해 단순한 장식품으로 사용되던 전복은 중국인에 의해 그 맛이 알려지게 되었고, 유럽이나 미국 동부로 팔려 나갔다. 상어 또한 중국인에 의해 먹기 시작하였으며, 내장에서 뺀 기름이 사용되기 시작하였다. 게를 잡기 위한 통발과 시장형성으로 San Francisco부두의 많은 부분이 차지되었다. 1880년대부터 시작된 해조류의 채취는 처음에는 인디언들에 의해 시작되었으나, 곧 중국인들에 의해 본격화되었다. 광동성 지방민들의 초속식품의 하나인 오징어를 잡기 위해 중국인들은 배를 만들어 야간에 횃불을 밝혔다. 오징어는 곧 San Francisco 주민은 물론 태평양 연안주와 미국 전역에 있는 중국식당에서 수요가 지속되었다. 중국인들은 1849년부터 연어를 상업적으로 잡기 시작하였으며, Washington주에서 시작되어 Oregon, British Columbia, Alaska로 퍼진 통조림 공장은 주로 중국인의 노동력에 의해 운영되었다. 위와 같이 중국인들이 미국 수산업 분야에서 크게 활동하자 미국인들은 그들의 수산업 활동을 제재 또는 통제하고자 일정한 납세를 명시한 각종 법률, 특히 The Chinese Exclusion Act 등을 제정하였다. 미국 서부에서 중국인의 수산업은 미국인의 법적 제재, 중국인의 다른 직업으로의 이직 등으로 1940년대를 끝으로 막을 내렸다.

• Journal of Korea Foresty Energy
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• v.7 no.1
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• pp.11-21
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• 1987

To estimate the biomass, net production and nutrient distribution of Pinus Koraiensis and Quercus mongolica stand, experimental plots located in Kwangju of Kyonggi-do were selected. Ten sample trees selected account of DBH distribution were felled and the diagram of oven-dry weight distrubution of leaves, branches and stems for each 1m segment was constructed. The logarithmic regression equations between dry weight of each component and the variable of $(DBH)^2$ H obtained. The standing crops were estimated to be as much as 152.07 and 156.02 tons of dry matter per hectare in P. koraiensis and Q. mongolica stand respectively. The net production was estimated as 24.66 and 20.35t/ha$\cdot$yr and the net assimilation rate was 1.90 and 3.42kg/kg$\cdot$yr in same order. Particulary large proportions of nitrogen. calcium and magnesium were found in soil of P. koraiensis stand, phosphours and potassium in overstory of it. At Q. mongolica stand, large proportions of nitrogen. phosphorus. potassium and magnesium were found in soil and calcium in overstory. The amounts of litter fall was 4.013t/ha$\cdot$8 months in P. koraiensis stand and 3.490t/ha$\cdot$8 months in Q. mongolica stand.

• Journal of Korea Foresty Energy
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• v.7 no.1
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• pp.1-10
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• 1987

This study was carried out to estimate the aboveground biomass of Cryptomeria japonica and Chamaecyparis obtusa which was planted in Changsong district, the southern part of the Korean peninsula. Nine sample trees at each plot(20m x 20m drom C. japonica of 20-year-old and C. obtusa of 25-year-old, according to DBH distribution. were felled to measure the dry weights of stem, branches and leaves sectioned respectively. Since it is very difficult to separate leaves from twigs. all green parts including pure leaves and twigs were tentatively treated as 'leaves'. 1. The logarithmic regression equations between dry weight of each component (stem. branches. leaves land the variable of $(DBH)^2{\cdot}H$ were obtained (Table 6). The aboveground standing crops was estimated 108. 75ton/ha in C. japonica and 112.56 ton/ha in C. obtusa. Percentage of each part based on the aboveground standing crop in stand was and in order of stem >leaves>branches for C. japonica and in order of stem> branches> leaves for C. obtusa repectively. 2. Net production of each stand was estimated as 1:3.32ton/ha/yr in C. japonica and 11.69ton/ha/yr in C. obtusa. and its composition was in order of stem>leaves>branches for both species. 3The net assimilation rate was estimated as 1.10 and 1.2lkg/kg/yr, the efficiency of leaves to produce stem was 0.71 and 0.75 kg/kg/ha and biomass accumulation ratio was 8.16 and 9.63kg/kg/yr in each stand of C. japonica and C. obtusa respectively.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.146-152
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• 2016

Due to complicate canopy structures of Irwin mangoes grown in greenhouses, it is difficult to determine their growth parameters accurately. Leaf area, leaf fresh weight, and leaf dry weight are widely used as indicators to diagnose the tree growth. Therefore, it is necessary to establish models that can non-destructively estimate these growth indicators. The objective of this study was to establish regression models to estimate leaf area, leaf fresh weight, and leaf dry weight of Irwin mangoes (Mangifera indica L. cv. Irwin) by using leaf length, leaf width, petiole length, and SPAD value. The input values of leaf length, leaf width, petiole length, and SPAD value of 6-year old Irwin mangoes were measured, and the corresponding output values of leaf area, leaf fresh weight, and leaf dry weight were also measured. After 14 models were selected among the existing models, coefficients of the models were estimated by regression analysis. Three models with higher $R^2$ and lower RMSE values selected. In validation the $R^2$ values for the selected models were 0.967, 0.743, and 0.567 in the leaf area, leaf fresh weight, and leaf dry weight models, respectively. It is concluded that this models will be helpful to conveniently diagnose the growth of the Irwin mango.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.26-34
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• 2015

This study was conducted to examine the morphological characteristics and variations of the 6 populations of Pourthiaea. villosa (Thunb.) Decne. var. villosa in Korea. The ANOVA results showed that the populations were significantly different in 18 of the 21 quantitative characteristics that were analyzed. In the results of principal component analysis, 6 principal components (PC) represented 68.28% for the total variations. 'Petiole length' (0.764), 'Leaf shape' (0.834), 'Leaf length' (0.753), 'Crown diameter' (0.663), 'Inflorescence width' (0.492), and 'Leaf base shape' (0.721) showed the highest contribution to PC1, PC2, PC3, PC4, PC5, and PC6, respectively. According to the results of cluster analysis, one cluster comprised only 'Goesan-gun Ssanggok Valley' population. 'Namhae-gun Mijori Evergreen Forest' population was grouped with 'Hamyang-gun Sang Forest' population, which was the nearest subgroup. Further, 'Namhae-gun Geum Mountain' population, 'Jindo-gun Cheomchal Mountain' population, and 'Jeju-si Barimae Parasitic volcano' population were placed in the same cluster.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.193-198
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• 1998

Experiments were conducted to investigate the population fluctuation, developmental periods, fecundity, hatching rate and demage of Citrus red mite (Panonychus citri M.) on Yuzu trees (citrus junos T.) from 1996 to 1997. Citrus red mite occurred from May to November and made two peaks. The first peak was in July to August and the secondary peak was in October. Density of the second peak was higher (9.5 miteslleaf) than that of the first peak. In the constitution rate of each developmental stage of citrus red mite on Yuzu leaves, egg stage occupied 85%. At the four constant temperature (15, 20, 25, 30 + 1$^{\circ}$C, RH 60 + lo%, 14L- IOD) conditions, the developmental period from egg to adult was 41 .l, 15.5, 11.0 and 9.4 days ; Mean longevity of adult was 23.3, 8.3, 6.3, and 6.1 days; Mean number of egg laid per female per day was 1.6, 3.2, 4.5, 4.0 eggs; Mean hatching rate was 66.6, 85.7, 90.7 and 94.7% at above temperature, respectively. When sprayed acaricide at different density of Citrus red mite, the growth of young Yuzu tree were better at low density. Defoliation rate during winter was 13.5, 20.6, 53.1, 72.6% at 4 control density 1 , 3, 6 mites per leaf and uncontrolled (10 ( ). When every time spray acaricide under 3 mites per leaf, defoliation rate during winter suppressed above 50% compare to uncontrol 72.6%.

• The Journal of Fisheries Business Administration
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• v.35 no.1
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• pp.133-168
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• 2004

The purpose of this study is to examine the state and characteristic of seafood marketing in Korean West Coast during the colonial period ruled by Japan. To accomplish the purpose, we tried to set the fisheries statistical database by reviewing of $\boxDr$Statistical Annual Report of Chosun Chongdokbu$\boxUl$ and $\boxDr$Official Report of Chosun Chongdokbu$\boxUl$. A trend analysis was carried out with the data. Also, by reviewing of articles related to the state of seafood marketing via $\boxDr$Daehan Maeil Newspaper$\boxUl$, $\boxDr$Maeil Newspaper$\boxUl$ issued at the period, we could find out some meaningful findings which backed up the statistics in realistic facts. For numbers of businessman in seafood marketing, it was clear that the number of Japanese businessmen increased more quickly than that of Korean compared with other sphere of fisheries. That means Japanese grasped Korean seafood market in a short time. In price of seafood in terms of cities, Kunsan was comparatively higher than Incheon and Mokpo. In price of seafood in terms of species, ‘Snapper’ was mostexpensive, and ‘Mackerel Pike’, ‘Anchovy’, ‘Mullet’, ‘Eel’, ‘Flatfish’ followed in that order. In price of a species in terms of ‘Yellow Croaker’, which was famous in West Sea, ‘Croaker with salt’ was more expensive than dried and fresh one. For the transition trend of number of fish market, we could ascertain that the number of market increased until 1919, however, it decreased slowly from 1932. That means Japanese government went to war against China from 1931. Of the West Coast, the number of fish market in Chungnam province was most high, but that of Chonbuk outrun from 1940. At that time, the number of fish market in West Coast reached to 34% out of that of whole country. In 1919, the proportion of seafood sales amount of West Coast neighboring provinces, such as Kyunggido, Chungnam, and Chonbuk, was 23% of whole country which rose to 28% in 1929, and 29% in 1939. Therefore, we could assure that seafood marketing was very active at that time in the region. When we consider the trend of seafood export at the main ports of West Coast, in 1910's, the export through Mokpo and Inchon port was very live but that of Kunsan was very tiny. However, in 1920's, the export amount of Inchon port did not much change, but that of Mokpo decreased, whereas, that of Kunsan increased. In the early and middle of 1910' s which was around beginning of Japanese ruling period, we realized that the imperialist Japan was very eager in political efforts to enhance the mind of seafood's quality improvement through the opening of several fisheries competitive shows and fairs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.3
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• pp.202-205
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• 2010

Introduction: The aim of the present study was to investigate the effect of mechanical irrigation in combination with mouthwash of antimicrobial agents on salivary bacterial counts. Materials and Methods: This study was performed with a randomized study employing a panel of 40 healthy volunteers (20 males and 20 females) between the age of 26 and 32 years. Volunteers were randomly put in one of four treatment groups. In the first group, 0.2 mL of non-stimulatory saliva was collected from every subjective person. Then, saliva was collected after rinsing with chlorhexidine (CHX) for 1 minute. In the second group, non-stimulatory saliva was collected, and then saliva was collected after rinsing with CHX and irrigation with saline. In the third and fourth groups, the same procedures as the first and second groups were performed with povidone iodine (PVI) instead of CHX. All of these samples were cultured for 48 hours aerobically. The reduction rates of colony-forming units (CFU) were calculated for each group. The reduction rate between each group was tested statistically using student t-test. Results: Using CHX in combination with saline irrigation showed a significant decrease of the salivary bacterial CFU when compared with only using CHX.(P<0.01) And using PVI with saline irrigation showed a little decrease of the CFU when compared with only using PVI, but there was no statistical significance.(P>0.01) Conclusion: It was concluded that the CHX or PVI used with saline irrigation made the salivary bacterial counts reduced more than when CHX or PVI was used alone as an oral antiseptic agent.