• Title/Summary/Keyword: Turnover Rate

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Short Term variability of the Phytoplankton Populations in Masan Bay: I. Dynamics (마산만 식물플랑크톤의 단기적 변화양상 : 1. 동태)

  • PAE, SE JIN;YOO, SIN JAE
    • 한국해양학회지
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    • v.26 no.1
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    • pp.67-76
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    • 1991
  • Masan Bay is infamous for its severe eutrophication, exemplified by frequent red tide incidences and anoxic conditions. We carried out daily observations for 16 days at one site immediately after the summer rainy season in 1988 on the basis that shorter observation intervals be necessary to observe a process with high turnover rate. in spite of the relatively short survey period, we could observe dramatic changes in abundance and composition of the phytoplankton populations. Cell densities and chlorophyll concentrations changed in the magnitude of 70 and 10 times, respectively, Skeletonema costatum, a diatom species, dominated the first peak of phytoplankton biomass and was followed by Prorocentrum minimum, a dinoflagellate species, which occurred dominantly in the second peak after about a week, form the viewpoint of time scale, we suggest that at least a weekly sampling might be appropriate in complex coastal environments as Masan Bay. While stratification enabled high production in the surface layer, it hindered the transport of silicate from bottom to the surface, which in turn limited the prolonged growth of diatoms. Ensued second peaks of silicate and diatom abundance in the surface layer suggest periodic flux of silicate from bottom across the discontinuity driven by tidal currents.

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Development and Application of Critical Pathway for Nasal Bone Fracture Patients (코뼈골절 환자에서 표준진료지침의 개발과 적용)

  • Hwang, Kun;Shin, Jung Yae;Lee, Hye Kyung;Lee, Hwan Jun
    • Quality Improvement in Health Care
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    • v.10 no.2
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    • pp.154-163
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    • 2003
  • Purpose: The aim of this study is to develop and apply the critical pathway to the nasal bone fracture patients and to elucidate its effect. Methods: Critical pathway (CP) sheet and questionnaire were developed by a team approach. Critical pathway were applied to 30 nasal bone fracture patients (CP group) from June 2001 to November 2001. Length of hospitalization, cost for hospitalization and bed turnover rate of CP group were compared to those of the 30 patients who had same disease entities and treated by conventional regimen (control group). Results: Length of hospitalization in the CP group (4.20 day) were significantly shorter than that of control group (6.21 day). Mean cost for hospitalization of the CP group (492,106 won) were significantly lower than that of control group (678,376 won). Bed turnover rate in CP group (2.5) were higher than that of control group. The patients satisfaction for the medical personnel, explanation regarding operation procedure, therapeutic operation fee, and length of hospitalization were all affirmative. Conclusion: Critical pathway that we developed for nasal bone fracture definitely improved the quality of treatment and lowered cost of medical service. Furthermore, other critical pathways should be developed for another facial trauma patients.

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Settlement and recruitment of Mactra veneriformis R. around the inshore of Kunsan, Korea (군산연안 동죽, Mactra veneriformis의 침강과 가입)

  • RYOU Dong-Ki;CHUNG Sang-Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.5
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    • pp.667-676
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    • 1995
  • Settlement, recruitment, growth and production of Mactra venerifomis were investigated at Kunsan tidal flat located in the west coast of Korea from lune 1993 to May 1994. High density of planktonic larvae of M. veneriformis was observed between the mid and early July in 1993. The size of the newly settled larvae ranged from 250 to 350um in shell length with mean density of 601$inds.\cdot m^{-3}$. Recruitment of M. veneriformis larvae was occurred mainly in the mid June to mid July 1993. The larvae have no substratum preference during the larval settlement phase. Mortality of larval was affected by environment (substratum, exposure time, density of adult clams). After settlement they grew until November, and stopped growing in winter from December. The estimated turnover rate of M. veneriformis larvae was estimated as high as 4.91 and 4.94. Annual production of the 0-age group was estimated to be 2,900g $m^{-2}\;\cdot\;yr^{-l}$, which was relatively high compared with those of other age groups.

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The Impact of the Environment Management on Steel Enterprise' managerial Performance (철강기업의 환경경영이 경영성과에 미치는 영향)

  • Lee, Dong-Won;Seok, Kee-Joon;Lee, Ki-Hwan
    • Journal of Environmental Policy
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    • v.9 no.4
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    • pp.29-52
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    • 2010
  • This paper analyzes the firm's financial characteristics, influence over the adoption of the ISO 14001 adoption in our analyses. We used the T-test, a logistic regression analysis. We chose 112 Steel Enterprises from Korea Accreditation Board. The independent variables are current ratio, debt ratio, fixed assets to net worth and fixed liabilities, gross margin on sales, total assets turnover, net sales growth rate. This study tests three hypotheses on management performance of adoption of ISO 14001. The main findings are as follows. The first hypothesis is supported in terms of debt ratio, fixed assets to net worth and fixed liabilities, net sales growth rate at the 1%, 5%, 5% significance level. The second one is supported in terms of current ratio, debt ratio, fixed assets to net worth and fixed liabilities at the 10%, 1%, 1% significance level. The third one is supported in terms of gross margin on sales, total assets turnover at the 1%, 10% significance level. These findings have important implications

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The Effect of Dietary Calcium Level on Biochemical Variables of Bone Metabolism in Ovariectomized Female Rats (식이 칼슘량이 난소 절제한 흰쥐에서 골대사 지료에 미치는 영향)

  • 최미자
    • Journal of the East Asian Society of Dietary Life
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    • v.6 no.3
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    • pp.295-305
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    • 1996
  • This study was done to evaluate the effectiveness of dietary calcium level(a diet which met 100% or twice the calcium level in AIN-76 diet) on preventing bone loss in ovariectomized rats. Forty female Sprauge-Dawley rats(body weight 200$\pm$5g) were divided into two groups. One group were ovariectomized(Ovx) while the others received sham operation(Sham). Thereafter, each rat group was further divided into normal calcium diet(NCD, 0.52%) and high calcium diet(HCD, 1.04%) sub-groups. All rats were fed on experimental diet and deionized water ad libitum for 8 weeks. Urinary pyridinoline & creatinine and serum estradiol, luteinizing hormone, calcium, phosphate, total protein, albumin, alkaline phosphatase and osteocalcin were determined. There were no significant differences in serum calcium. total protein and albumin in the two groups(Ovx vs Sham) of rats. Ovariectomized rats had significantly lower estradiol than sham operated rats. There was a highly significant correlation between total bone mineral density(TBMD) and overall level of esteradiol(r=0.59, p<0.05). Total bone mineral density did not correlate significantly with ALP or osteocalcin, although a negative trend was evident. However, the rats fed high calcium diet had a lower crosslinks value and osteocalcine than the rats fed normal calcium diet. An increased rate of bone turnover is usually associated with a decrease in bone mass bexause bone formation at each remodeling site is never as great as resorption. Ovariectomized rats fed high calcium diet had a lower crosslink value and osteocalcin; it means high cacium diet decreased bone turnover rate. The findings from the present study demonstrated that bone loss due to ovarian hormonal deficiency can be partially prevented by a high calcium diet. Futhermore, these findings support the strategy of the use of a high calcium diet in the prevention of estrogen depletion bone loss (postmenopausal osteoporosis).

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Detection of Vibrio vulnificus in Fish Farm and Bactericidal Methods on this Bacteria (가두리 양식장의 Vibrio vulnificus 검출 및 제어 방법)

  • 성치남;송계민;이규호;양성렬
    • Korean Journal of Microbiology
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    • v.38 no.4
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    • pp.281-286
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    • 2002
  • Detection of Vibrio vulnificus in fish farm and searching for the bactericidal methods on this bacteria were studied. To detect this microorganism in sea water, mud, fish and mussels, selective isolation methods and detection of vvhA gene were used from January to October,2000. V. vulnificus was detected from May when the water temperature was over $17^{\circ}C$. From June to September, higher than $19^{\circ}C$, this bacteria could be isolated from most of the samples. Freezing and refrigerating did not inhibit the growth of V. vulnificus. Citric acid did not show the bactericidal effect, but more than 500 mg/l of EDTA did. With the aid of UV and photocatalyst, $TiO_{2}$ showed bactericidal effect after 15 minute treatment. Photocatalytic system consisted of glass bead coated with $TiO_{2}$ and UV illumination showed bactericidal effect on V. vulnificus at the turnover rate of 0.2/min.

Cyanide Degradation by Two Recombinant Cyanide Hydratases (Recombinant Cyanide Hydratases에 의한 시안화물 분해)

  • Kwon, Sung-Hyun;Cho, Dae-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.6
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    • pp.1287-1291
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    • 2009
  • The genes of cyanide hydratase(CHT), a kind of nitrilases whichhydrolyze cyanide to formamide were extracted from N. crassa and A. nidulans, the two fungal strains. The recombinant forms of the CHT originated from N. crassa and A. nidulans were prepared with N-terminal hexahistidine purificationtags or no tags, and expressed in E. coli. The enzymes were purified using immobilized metal affinity chromatography. They were compared according to their pH activity profiles, and kinetic parameters. The N. crassa CHT has the wider pH range of activity above 50% and three-fold higher turnover rate (6.6 ${\times}$ $10^8$ $min^{-1}$) than the A. nidulans, meanwhile the CHT of A. nidulans has the higher $K_m$ value. Expression of CHT in both N. crassa and A. nidulans were induced by the presence of KCN, regardless of any presence of nitrogen sources. Max. 82% of KCN was degraded in 60 min for biological degradation tests.

The Removal Rates of the Constituents of Litters in the Littoral Grassland Ecosystems in the Lake Paldangho Ⅶ.Cadmium and Lead (팔당호 연안대 초지생태계에서 낙엽 구성성분의 유실률 Ⅶ.카드뮴과 납)

  • 최선영;이인숙;장남기
    • Asian Journal of Turfgrass Science
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    • v.10 no.4
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    • pp.305-313
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    • 1996
  • This study was carried out to investigate the removal rates of Cd and Pb of the litters in the Phragmites communis. Miscanthus sacchariflorus, Typha angustata, Scirpus tabernaemontani grassland aquatic ecosystem in the lake Paldangho. The annual production of Cd and Pb were 0.005g /$m^2$ , 0.21g /$m^2$in P. commumis, 0.004g /$m^2$, O.08g /$m^2$ in M. sacchariflorus, 0.023g /$m^2$, 0.42g /$m^2$ in T. angustata and 0.020g /$m^2$, 0.23g /$m^2$ in S. tabernaemontani respectively. The removal rates of Cd and Pb of the litters were 0.83, 0.85 in P. communis. 0.36, 0.54 in M. sacchariflorus, 0.61, 0.51 in T. angustata and 0.76, 0.71 in S. tabernaemontani, respectively. The times required to decay 50, 95, 99 percent of the steady state level and turnover values of cadmium on the grassland floor were 0.83, 3,60, 6.00 years in P. communis. 1.90, 8.24, 13.74 years in M.sacchariflorus, 1.15, 4.96, 8.27 years in T. angustata and 0.91, 3.95, 6.58 years in S. tabernaemontani The times required to decay 50, 95, 99 percent of the steady state level and turnover values of lead on the grassland floor were 0.81, 3.51, 5.86 years in P. communis. 1.28, 5.56, 9.26 years in M. sacchariflorus, 1.37, 5.94, 9.90 years in T. angustata and 0.97, 4.21, 7.02 years in S. tabernaemontani. Key words: Removal rate, Accumulation, Paldangho, Cadmium, Lead, Phragmites communis Miseanthus sacchariflorus, Typha angustata, Scirpus tabernaemontani.

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Secular chang of density, litterfall, phytomass and primary productivity in mongolian oak(quercus mongolica)forest (신갈나무 숲의 林木密度, 落葉量, 植物量 및 1次 純生産量의 經年 變化)

  • Kwak, Toung-Se;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • v.15 no.1
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    • pp.19-33
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    • 1992
  • The density, litterfall, phytomass, and primary productivity for 7 years in quercus mongolian forest locasted at mt. nambyengsan, pyeongchang-gun, gangwon provance in central part of korean peninsula were estimated quantitatively. at the first year in 1984, a stand had 1, 450 trees/ha in tree density, which was 0.67 of skewness and 0.54 of kurtosis in frequency distribution, however, at the 7th year in 1990, the stand had 1, 133 trees/ha in the density with 22%(or 316 tree/ha)in mortality, which was 1.16 of skewness and 1.89 of kurtosis in the frequency. annual mean litterfall was 5 ton DM/ha, which was composed of 68% of leaves, 17% of branches, 3% of bud scales, 9% of arcons and cups, 0.7% of flowers and others. the phytomass of tree layer for 7 years was gradually increased from 149.7 ton DM/ha at the first year to 188.5 ton DM/ha at the 7th year.annual net productivity for the tree layer studied ranged from 8.76 ton DM/ha.yr-1 to 11.62 ton DM/ha. yr-1 with heavy fluctuation year by year. average annual productivity of the stand of trunk, branches, leaves and roots for 7 years were 4.42, 0.67, 3.85 and 1.29 ton DM/ha.yr-1, respectively. turnover rate of the stand was 6.9% at the first year and 5.6% at the 7th year. such fluctuation of the productivity was caused by the chang of density, mortality, mortality and turnover rate.

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A Study on the Impact of Organizational Commitment on Workers' Turnover Intention and Organizational Performance: Based on Analysis of Welfare Organizations in Busan, Korea (조직몰입이 이직의도와 사업성과에 미치는 영향: 부산지역 사회복지조직을 중심으로)

  • Seo, Jong-Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.4
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    • pp.215-225
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    • 2016
  • There is growing attention towards the performance of non-profit organizations (NPO) as cases of moral hazard have emerged as social issues and the public becomes interested in the accountability of NPOs. Social welfare is among the representative service areas of NPOs, and it is regarded as a human service because it is delivered by people. Therefore, human capital-measured by criteria such as levels of organizational commitment-significantly affects the performance of social welfare organizations. However, these organizations have a high turnover rate due to inadequate working environments, heavy workloads, intensive work, and poor remuneration. Against this background, we surveyed social welfare organizations located in Busan and examined how workers' organizational commitment affects their turnover intention and the performance of the organization. For data analysis, SPSS WIN 18.0 was used, and variable-specific frequency analysis and technical statistics were used to identify general properties. A Pearson correlation analysis and a multiple regression analysis were conducted to investigate correlations and causal relationships among main variables. The results showed that the social workers' level of organizational commitment was 3.36 for normative commitment, 3.07 for continuance commitment, and 2.75 for affective commitment. The level of normative commitment was slightly higher than moderate, continuance commitment was close to moderate, and affective commitment was lower than moderate. The surveyed social workers' turnover intention was 2.71, and organizational performance was 2.79; both of those results were slightly lower than moderate. It was observed that affective commitment, marital status, workload, and age affected social workers' turnover intention. Their affective commitment, gender, and age affected the organization's performance. These results suggest that, for launching or operating an NPO, it is important to manage human capital effectively, particularly their affective commitment, to lower workers' turnover intention and improve organizational performance.

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