• Title/Summary/Keyword: Distribution science

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The Distribution of Zooplankters with a Note on their Feeding in the Wet Lands of the Lower Han River (한강 하구 습지의 동물플랑크톤 분포 및 섭식)

  • Kim, Saywa
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.566-572
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    • 2017
  • For four times, zooplankton collection were conducted seasonally in October 2015-July 2016 at five sites located in the wet lands of the lower Han River, ie., Si-am, Sung-dong, Gong-reung stream, San-nam and Jang-hang. A total of 46 species of zooplankton were collected, which comprise 25 species of rotifers, seven cladocerans, ten copepods, and one species of nematod, ostracod and decapod, respectively. No brackish and marine species were distributed except for two species of brackish water copepods. Prosperity in the species number of 15 species was observed in October at Sung-dong and Jang-hang. The maximum abundance was recorded in March at Si-am with $8,000indiv.\;L^{-1}$ with the explosion of Brachionus calyciflorus. Other sites also showed high abundances in March with the abundance higher than $5,000indiv.\;L^{-1}$. Except in March, the abundance levels were recorded as less than some hundred $indiv.\;L^{-1}$ throughout the study. Species diversity varied between 0.4-1.8. The gut contents of the copepodite showed that various diatoms might be their major food items, and lots of unidentified materials were also observed. The environmental conditions of water temperature, pH and dissolved oxygen content showed to vary $10.1-28.2^{\circ}C$, 7.1-8.6 and $4.5-11.0mg\;L^{-1}$, respectively.

Development of Sequential Sampling Plans for Tetranychus urticae in Strawberry Greenhouses (딸기 온실에서 점박이응애의 축차표본조사법 개발)

  • Choe, Hojeong;Kang, Juwan;Jung, Hyojin;Choi, Sira;Park, Jung-Joon
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.427-436
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    • 2017
  • A fixed-precision-level sampling plan was developed to establish control of the two-spotted spider mite, Tetranychus urticae, in two strawberry greenhouses (conventional plot, natural enemy plot). T. urticae was sampled by taking a three-leaflet leaf (1 stalk) from each plant (3 three-leaflet leaves) from each sampling position. Each leaflet was divided into three different units (1-leaflet, 2-leaflet, and 3-leaflet units) to compare relative net precision (RNP) values for selection of the appropriate sampling unit. The relative net precision values indicated that a 1-leaflet unit was more precise and cost-efficient than other units. The spatial distribution analysis was performed using Taylor's power law (TPL). Homogeneity of the TPL parameters in each greenhouse was evaluated by using the analysis of covariance (ANCOVA). A fixed-precision-level sequential sampling plan was developed using the parameters of TPL generated from the combined data of the conventional plot and natural enemy plot in a 1-leaflet sampling unit. Sequential classification sampling plans were also developed using the action threshold of 3 and 10 mites for pooled data. Using the results obtained in the independent data, simulated validation of the developed sampling plan by Resampling validation for sampling plan (RVSP) indicated a reasonable level of precision.

Practical Evaluation of Intellectual Capital (IC) Measurement Tool for Contract Foodservice Management Company (위탁급식전문업체 지적자본 측정도구의 운용시험 평가)

  • Park, Moon-Kyunkg;Yang, Il-Sun
    • Journal of Nutrition and Health
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    • v.38 no.10
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    • pp.880-894
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    • 2005
  • The purposes of this study were to a) measure the IC identified of CFMC (contract foodservice management company) ,b) examine IC circumstance of CFMC, c) evaluate practically IC measurement tool of CFMC, and d) present information for selecting an adequate CFMC to clients. The questionnaires of IC measurement were handed out to 108 CFMCs, there composing of main office employees, foodservice managers, customers, and clients of 207 school,38 hospital, and 86 husiness/industry foodservices. The statistical data analysis was completed using SPSS Win (ver 12.0) for descriptive analysis, t-test, Mann-Whitney U test. First, CFMCs had operational experience for an average of 8 years and 8 months, and served an average of 38,540 meals a day. Most of the respondent companies specialized in the school foodservice field and managed an average of 66 clients for the contract period of 2 years and 3 months. Second, the respondent companies had gotten a score of 77.78 points for the total average, 77.7 points in the large enterprise group and 78.1 points in the small and medium-sized enterprise group. Therefore, the minimum number of points for the accrediting license on Qualification is suggested to be over 70 out of a 100 point scale; this study would be serve as reference for the certification license on qualification. On the level of evaluation category, the scores were 14.15 to 20 points on $\ulcorner$finance$\urcorner$, 19.24 to 25 points on $\ulcorner$customer$\urcorner$, 19.33 to 25 points on $\ulcorner$process$\urcorner$, 14.31 to 20 points on $\ulcorner$human resource$\urcorner$, and 8.6 to 10 point on $\ulcorner$renewal and development$\urcorner$ . $\ulcorner$Renewal and development$\urcorner$ and $\ulcorner$customer focus$\urcorner$ received better grades than other evaluation categories. Third, $\ulcorner$Finance$\urcorner$ indicated similar distribution overall. Small and medium-sized companies had lower grades than large companies on 'market ability' of $\ulcorner$customer$\urcorner$ , but, clients of small and medium-sized companies had higher grade for 'client satisfaction' than large companies. Most of the companies supported 'infrastructure support for foodservice operation' of $\ulcorner$process$\urcorner$ by the main office of CFMCs, but, the branch chain offices of CFMCs were not applied efficiently. Large companies made more effort to improve the 'employee ability' of $\ulcorner$human focus$\urcorner$ than small and medium-sized CFMC. The 'research and development cost' of $\ulcorner$renewal and development$\urcorner$ was increased compared to the previous year. In conclusion, if CFMCs were to perform self-evaluation and a routine checkups by utilizing CFMC's IC measuring tool, improvements in CFMC operational capacities as well as foodservice quality can be noted. (Korean J Nutrition 38(10)'880$\sim$894,2005)

The Effect of Distributor Private Brand Product Type on Consumer Attitude

  • Kim, Eun-Hee;Kim, Eun-Hee;Kim, Moon-Jung
    • Asian Journal of Business Environment
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    • v.1 no.1
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    • pp.13-20
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    • 2011
  • This study is conducted to verify existing differences in consumer attitude according to distributor type and PB product type. Pre-test was conducted for this study in order to select the distributor and to classify the product type, FGI was conducted with 10 graduate students of K university in Kyong-gi. This study survey housewives, office workers, and university students excluding the participants in the pre-test. In the final analysis, research hypothesis is verified through the data of 280 answers in Korea. This research is conducted with a factor design of 3 types of distributors -department store, discount store, convenience store-and 2 types of product -utilitarian product, hedonic product. To verify the hypotheses, ANOVA is carried out. Reliability test of each measurement variables, Cronbach α coefficient is used. For each analysis, SPSS Windows 15.0 statistical program is used. The findings suggest that First, according to the size and characteristics, distributors are classified into department stores, discount stores, and convenience stores and it is verified whether if there are differences in consumers' attitude (product attitude, brand attitude and purchase intention) by the effect of different distributors. Results showed that product attitude is statistically significant. Second, product type is classified by two categories according to whether the product seeks for practicality or emotional pleasure - Utilitarian product and Hedonic product. In this context, the result after verifying whether if there is difference in the attitudes -product attitude, brand attitude, and purchase intention - in accordance with the product types is shown that utilitarian products makes bigger difference compared to hedonic products. Third, it is confirmed that there is interaction effect between product attitude and purchase intention according to the distributer type and product type. However, we find that in terms of brand attitude, there is no interaction effect. The implications of this research is as the following. First, we propose the need of PB product development and marketing strategy, which considers the product types in accordance with the scale and features of each distributor. Second, PB products should break away from the simplicity of standardized products and consider the different features of distributors. Distributors will be in need of a strategy to build a compelling brand that can differentiate itself from other distributors. This will contribute to the improvement in reliability and formation of product value.

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Annual Reproductive Cycle and Embryonic Development within the Maternal Body of the Marbled Rockfish, Sebastiscus marmoratus from the Cheju Island (제주산 씀뱅리 (Sebastiscus marmoratus)의 생식년주기와 체내자어 발달)

  • BAE Hee Chan;CHUNG Sang Chul;LEE Jung Jea;LEE Young Don
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.4
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    • pp.489-499
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    • 1998
  • Gonadal development, reproductive cycle and embryonic development of the marbled rockfish, Sebastiscus marmoratus were investigated histologically. A total of 1,035 specimens were collected from the Cheju Island from July of 1992 to May of 1996. Gonadosomatic index (GSI) in female reached the maximum during October to March, thereafter, the values decreased from Norvember to April. GSI in male reached the maximum in September (before one to three months of the female's maximum), thereafter, the values rapidly decreased from October to December. The annual reproductive cycle can be divided into five stages in female and four stages in male: females, Growing(June to September), Mature(September to February), Ripe and copulation(October to March), Gestation and parturition(November to April), Degenerative and resting(December to May); in males, Growing(April to July), Mature(August to November), Ripe and copulation(September to December), and Degenerstive and resting(November to March). Size frequency distribution of eggs and larvae showed non-synchrony. Maternal larvae parturition occurred one or two time during November to April. Mean length of the larvae parturition was 3.5 mm. Mean number of eggs and maternal larvae for the 15 cm minimum class of female was 58,377, and fecundity increased with the increase of total length and body weight.

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Intraspecific Zonation of the Benthic Amphipod Pontogeneia rostrata in Relation to Diel and Tidal Cycles (저서성 단각류 Pontogeneia rostrata의 종내 대상분포와 주야-조석주기)

  • YU Ok Hwan;SUH Hae-Lip;SOH Ho Youn
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.4
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    • pp.500-507
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    • 1998
  • Using a sledge net, the benthic amphipods were taken over one cycle of the neap and spring tides in January 1993 at the sandy shore surf zone of Dolsando, southern Korea. From these samples, we investigated the diel and tidal effects on the intraspecific zonation of Pontogeneia rostrata. The density of p. rostrata was higher during neap tide than spring. Of three categories (adult males and females and juveniles), juveniles and males attained to its highest density during neap and spring tides, respectively. Length- frequency data show that the high mortality of juveniles seemed to occur in winter. In the surface at night, it is significant that juveniles were significantly more abundant during neap tide than spring, whereas both adult males and females were more abundant during spring tide than neap. This suggests that the vortical migration patterns of juveniles and adults vary with the type of tides. During flood of spring tide, more than $90\%$ of population collected at the area above the mean sea level (MSL) were adults. With a decrease of female/male ratio, size of males increased there but that of female did not change, indicating an active migration of large males. This behavior can provide an extension of distribution area far large males, and also give a competitive advantage to large male against small one for mate and feeding. Although adult p. rostrata was collected at 100 cm above MSL at night during spring tide, a major portion of population as usually present on the shore below MSL. The center of zonation was restricted from 50 cm to 250 cm below MSL.

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Study on the Production and Management of Aquatic Animal : Application of ELISPOT-Assay for the Detection of Antibody Secreting Cells in Flounder, Paralichthys olivaceus (수산생물의 생산과 관리에 관한 기초연구 : ELISPOT 기법을 이용한 넙치의 항체생성 세포분석)

  • HA Jai Yi;PARK Jun-Hyo;KIM Myoung Sug;CHUNG Joon-Ki;JEONG Hyun Do
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.420-426
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    • 1999
  • We examined the immune response in flounder, Paralichthys olivaceus, with immunization of formalin killed Edwardsiella tarda as an antigen. The ELISPOT-assay (enzyme-linked immunospot assay) was optimized technically and applied to count the number of total and specific antibody secreting cells (TASC and SASC) in lymphocytes of different lymphatic organs. Incubation of lymphocytes on 96 well plate for more than 2.5hrs came out enough time in ELISPOT-assay for counting the antibody secreting cells in the anterior kidney and spleen. However, too much of plate-coated antigen or rabbit anti-flounder immunoglobulin for SASC or TASC counting, respectively, was appeared to decrease the sensitivity of the assay system. Specificity of the system was also confirmed by the absence of TASC in lymphocytes treated with cycloheximide to prevent protein synthesis. The peak numbers of SASC appeared at wk 3 post immunization after that there was a sharp decrease and reached to almost zero at wk 7. In the spleen and kidney, the timing and numbers of SASC on peak response were concurrent without preferential organ distribution. The specific antibody level in the sera increased rapidly between wk 2 and 3 after immunization, i.e. like the specific cellular response found with ELISPOT-assay on that period, However, the remained high level of specific serum antibody from wk 5 after immunization until the end of experiment was clearly distinguishable from the kinetics of SASC response decreased sharply.

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Germination and Growth of Laminaria japonica (Phaeophyta) Microscopic Stages under Different Temperatures and Photon Irradiances (수온과 광량에 따른 다시마 초기 생활사의 발아와 성장)

  • KANG Rae-Seon;KOH Chul-Hwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.438-443
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    • 1999
  • Germination and growth of Laminaria japonica microscopic stages were investigated under crossed gradients of temperatures and irradiances, and the results related to the seasonal temperature regime in the southeastern coast of Korea. Germination rates of $70\~86\%$ were observed in the temperature range of $5\~20^{\circ}C$, however, at $25^{\circ}C$ no germination of meiospores was observed. The primary factor affecting germination rates at the temperature range of $5\~20^{\circ}C$ was irradiance: germination was significantly reduced at $150 {\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$. Vegetative cell production of female gametophytes was highest at $20^{\circ}C$, but plants were not fertile at the temperature. In the temperature range of $5\~15^{\circ}C$, higher irradiance caused females to reduce cell production, but increased fertility. Cell production was also low at lower temperatures with increased fertility rates. Optimal growth temperature for microsporophytes was $10^{\circ}C$ and their growth rates were light-saturated at $70 {\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$. We have concluded that meiospores released before July could develope to the young sporophytic stage in the southeastern coast of Korea which is off the southern limit of its geographical distribution. However, limiting factor in the development of natural sporophytic population in this region would be the upper temperature limit for the survival of young sporophytes, as water temperature at this area frequently exceeds $25^{\circ}C$ during the summer period.

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Growth and Survival of Laminaria japonica Areschoug at different densities (밀도에 따른 다시마(Laminaria japonica Areschoug)의 생장과 생존)

  • KANG Rae-Seon;KOH Chul-Hwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.444-451
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    • 1999
  • The effect of individual density on the growth and survival of Laminaria japonica was experimentally evaluated. Four density treatments of young sporophytes (0.63 cm In maximum length) grown in the laboratory were transplanted to the southeastern coast of Korea and their survivorship and growth rate were measured twice a month from January to July, 1996. Plants showed higher survivorship at low density. Final densities at three lowest densities were similar, ranging from 34 to 38 inds${\cdot}100 cm^{-2}$. Planis at the highest density, however, suffered greater decline than at lower densities, and only 21 plants remained at the end of this study. Mean frond size (length and width) fluctuated throughout the study period at four densities. During the first two mouths after outplanting, mean frond size was negatively correlated with initial density, However, the size was density independent after three months. As stand density increased, size-frequency distribution through time tended to be more positively skewed. The 10 largest plants grew faster in frond size and attained larger size in the lower density. There was a positive relationship between plant size and relative growth rate (or survival). The slope of yield-density (Y-D) relationships at four densities ranged from -0.060 to -0.137. The study suggests that density can strongly affect the survival and growth of this alga. The density-dependent survival and growth patterns, however, were not strictly consistent with those of terrestrial plants.

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Community Structure and Floristic Composition of Cymbidium goeringii Group in Korean Islets (한반도 도서지역 춘란집단의 종조성과 군락구조)

  • Song, Hong-Seon;Park, Yong-Jin
    • FLOWER RESEARCH JOURNAL
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    • v.18 no.2
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    • pp.110-116
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    • 2010
  • This text was analyzed and investigated the vegetation and floristic composition by ordination and classification of phytosociological method, to evaluate the species composition and community structure of Cymbidium goeringii group in Korean islets. In habitat of 33 plots, the mean altitude was 65.9m, the direction was the southeast slope, the mean slope was 7.9%. The coverage of Cymbidium goeringii was 4.5%. The appearing plants with the Cymbidium goeringii was the total 102 taxa, and it was the kind of trees 68 taxa (66.7%), herbs 34 taxa (33.3%), evergreen plants 36 taxa (35.3%) and deciduous plants 66 taxa (64.7 %) respectively. The frequency of appearing plant was the highest in the Eurya japonica (48.5%), followed by Pinus thunbergii (45.5%), Smilax china (36.4%), Carex lanceolata (33.3%), Hedera rhombea (33.3%), Machilus thunbergii (30.0%), Styrax japonicus (30.3%) and Pinus densiflora (27.3%), respectively. The vegetation of tree layer in Cymbidium goeringii group was classified into Pinus thunbergii community, Pinus densiflora community, Castanopsis sieboldii community and Quercus variabilis community. Pinus densiflora community showed a strong combination with Cymbidium goeringii group in Korean islets. Pinus thunbergii community among communities was combined with Castanopsis sieboldii community, and Pinus densiflora community and Quercus variabilis community were combined.