• Title/Summary/Keyword: return period

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Study on Investment Decision-making Factors of Informal Investors for Start-up Investment (비공식투자자의 창업기 투자의사결정요소 연구)

  • Kim, Tae-Nyeun;Park, Sun-Youmg;Sawng, Yeong-Wha
    • The Journal of the Korea Contents Association
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    • v.18 no.9
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    • pp.584-593
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    • 2018
  • The startup, which is a common noun to start a small business, has been recently one of main targets for policymakers due to its important role for job creation and considerable potential for sustainability of an economy. However, technological entrepreneurship decreased by 5.0% p from 2013 to 2016. The revitalization of entrepreneurial investment promoted by the government is mainly supported in fruitable venture companies at grow stage or 2~3 years before IPO through venture capital firms and angel funds. It is far from an investment at start-up. It is therefore necessary to motivate private investment to be active in the private start-up sector. In addition, the start-up investment requires institutional support and government support to meet the expectations of investors about the possibility of payback and profitability of private investment invested in the founding period. As a small entrepreneur at a comparably early stage in the lifecycle of business, investments for the startup are generally made by informal investors such as family, friends and fools, and their decision making processes are relatively non-programmed compared with ones for listed corporales such as venture capital and angel fund agency. This study focuses on analyzing decision making factors in investment, and verifying an impact of such factors, specifically the possibility of investment payback and investment profitability, in a decision-making process for the startup especially at the very early stage.

Coastal Complex Disaster Risk Assessment in Busan Marine City (부산 마린시티 해안의 복합재난 위험성 평가)

  • Hwang, Soon-Mi;Oh, Hyoung-Min;Nam, Soo-yong;Kang, Tae-Soon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.5
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    • pp.506-513
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    • 2020
  • Due to climate change, there is an increasing risk of complex (hybrid) disasters, comprising rising sea-levels, typhoons, and torrential rains. This study focuses on Marine City, Busan, a new residential city built on a former landfill site in Suyeong Bay, which recently suffered massive flood damage following a combination of typhoons, storm surges, and wave overtopping and run-up. Preparations for similar complex disasters in future will depend on risk impact assessment and prioritization to establish appropriate countermeasures. A framework was first developed for this study, followed by the collection of data on flood prediction and socioeconomic risk factors. Five socioeconomic risk factors were identified: (1) population density, (2) basement accommodation, (3) building density and design, (4) design of sidewalks, and (5) design of roads. For each factor, absolute criteria were determined with which to assess their level of risk, while expert surveys were consulted to weight each factor. The results were classified into four levels and the risk level was calculated according to the sea-level rise predictions for the year 2100 and a 100-year return period for storm surge and rainfall: Attention 43 %, Caution 24 %, Alert 21 %, and Danger 11 %. Finally, each level, indicated by a different color, was depicted on a complex disaster risk map.

Cyst formation of the marine ciliate, Vorticella sp. using MCCF medium (MCCF 배지를 이용한 해산 섬모충 Vorticella sp.의 cyst형성)

  • JUNG Min-Min;RHO Sum
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.317-319
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    • 1999
  • The ciliate, Vorticella was often observed in the rotifer mass culture tanks as common co-existing organism. This Vorticella performed as a predator for aquatic bacteria population in the rotifer mass culture tanks. This study was carried out to investigate a cyst formation medium of Vorticella in the laboratory for keeping Vorticella seed. The test organism Vorticella sp. was isolated from culture water of rotifer mass culture tanks. The cyst of Vorticella was formed by dried-method for the formation and maintainance of cyst. MCCF (Marine Ciliate Cyst Formation) medium was used for cyst formation (incystment), preservation and return to moving cell (excystment) of the marine ciliate, Vorticella sp. The cyst shape and size were ellipical type and $30.51 \pm1.98\;\mu$m (Avg. $\pm$ SD) of minor axis and $28.89 \pm2.12\;\mu$m (Avg. $\pm$ SD) of minor axis (n=10), The Vorticella cyst was kept in the room temperature ($10\~35^{\circ}C$) and total dark condition (24D:0L) during 1 year. The preserved cyst was transferred to moving cell state (excystment) only by the addition of fresh sea water in the MCCF medium. The five Vorticella sp. moving cells of excysted from cysts showed the growth up to 912$\pm$64 cells/10 ml in MCCF medium during the culture period of 16 days. This MCCF medium was very useful tool for cyst formation and species preservation of marine ciliate Vorticella.

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Distribution and Migration of Flying Squid, Ommastrephes bartrami (LeSueur), in the North Pacific (북태평양에 있어서 빨강오징어 Ommastrephes bartrami (LeSueur)의 분포 및 회유)

  • GONG Yeong;KIM Yeong Seung;KIM Soon Song
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.166-179
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    • 1985
  • The seasonal distribution and migration of flying squid, Ommastrephes bartrami (LeSueur), in the North Pacific were studied by means of mantle length, surface temperature, and catch and effort data of the Korean drift gillnet fishery from 1980 to 1983. The water temperature for the best fishing ranged from $15^{\circ}\;to\;16^{\circ}C$ in May through July and from $13^{\circ}\;to\;18^{\circ}C$ in August through January. High densities of flying squid were found in the thermal fronts with $18^{\circ}C$ isotherm in August and with $15^{\circ}C$ isotherm in September. The densities of flying squid were higher in the western region than in the eastern region in the North Pacific. The high densities of flying squid in the northwestern Pacific were attributed to the high gradients of oceanographic properties in the region. Migration models for flying squid were hypothesized based on the monthly distributions of catch per unit net, mantle length compositions by statistical blocks, and the hydrographic features of the North Pacific. The large flying squid moved to the northern region and to the central Pacific region earlier than the small sized group in the northward migration period (from June to August). Flying squid begin the reverse southward migration from the Subarctic Frontal Zone in autumn with onset of cooling and the development of Oyashio Current. The large sized group starts their southward return migration from more northern waters than the small sized group but the former moves past the later ana reaches the spawing ground first.

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Reuse Technology Development and Economic Evaluation of Dyeing Wastewater Treatment Sludge (폐수처리슬러지의 재활용기술개발 및 경제성 평가 -B염색조합을 중심으로-)

  • 임재호;이정연
    • Resources Recycling
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    • v.9 no.1
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    • pp.36-43
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    • 2000
  • This study was carried out for treatment and reuse of inorganic sludge from Fenton process at B dyeing wastewater treatment plant. The parameters for pilot-scale treatment system were derived from the results of this study. It was found that $COD_{cl}$ of the treated effluent became lower than 100 mg/l approximately on the optimal reaction condition. 2nd sludge which was generated after redissolving sludge was analyzed, and it showed that reduction ratio of ash in 2nd sludge and total dry sludge weight in comparison with current sludge were 85% and 65%. Also Fe salt in sludge was redissolved about 90~95% of initial Fe by weight. It was estimated almost ₩350,000,000 for sludge reuse process. It was estimated saving of about ₩1,300,000 per day (₩420,000,000 per year) in operating cost based on 30,000 $m^3$/d treatment, which these were about ₩430,000 per day in chemical, ₩1,100,000 per day in sludge transportation and ₩200,000 per day in equipment maintenance. Payback period with interest charge for investment cost was estimated about 10.5 months. Also, net present value (NPV) was ₩792,000,000 and internal rat of return (IRR) was about 110%.

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Design of Edtention Pond and Critical Duration of Design Rainfall in Seoul (유수지 설계를 위한 계획강우의 임계지속기간 -서울 지역을 중심으로-)

  • 이종태;윤세의
    • Water for future
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    • v.26 no.1
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    • pp.115-124
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    • 1993
  • This study is to determine the critical duration of design rainfall and to utilize it for the design of detention pond with pump station. To examine the effect of the duration and temporal distribution of the design rainfall, Huff's quartile method is used for the 9 cases of durations ranging from 20 to 240 minutes with 10 years return period, and the ILLUDAS model is used for runoff analysis. The storage ration which is the ratio of maximum storage amounts to total runoff volume, is introduced to determine the critical duration of design rainfall. The duration which maximizes the storage ratio is adopted as the critical duration. This study is applied to 18 urban drainage watersheds with pump station in Seoul, of which the range of watershed area is $0.24-12.70\textrm{km}^2.$ The result of simulation shows that the duration which maximizes storage ration is 30 and 60 minutes on the whole. It is shown also that the storage ration of 2nd- and 3rd-quartile pattern is larger than that of 1st- and 4th-quartile pattern of temporal distribution. A simplified empirical formula for Seoul area is suggested by using the regression analysis between the maximum storage ration and the peak ratio, and can be utilized for the preliminary design and planning of detention pond with pump station.

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A Study of the Nursing Needs of Hospitalized medical Patients by Means of Nursing History Form (간호력(Nursing History)을 통해 본 내과 입원환자의 간호요구)

  • 전경애
    • Journal of Korean Academy of Nursing
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    • v.7 no.2
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    • pp.1-10
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    • 1977
  • Personalized Patient centered nursing care is increasingly difficult to achieve despite the fact that it remains one of our consistent goals. So, we must find away to individualized nursing care. One means, to achieve this is by use of the nursing history form, which has been developed to help the nurse make maximum use of her limited time with the patient, by obtaining systematically the information needed to plan his nursing care. The nursing history form can be used to collect data about individual nursing needs but also it lends itself to the collection of epidemiological data relevant to the needs of patient population. So this study was undertaken in an attempt to describe the general characteristics of the population studied, to find out their perceptions and expectations related to their illness and hospitalization, to find out specific basic needs and to examine the relationship between the patients nursing needs and demographic characteristics through the responses to the nursing history questions. The study population defined and selected was all the patients (70) who were admitted to Yonsei University Hospital from October 1 - 15, 1975. The direct interview method was used and the data were categorized by the investigator, according to the nature of responses to each question and were subjected to the percentile and the chi- square tests. The findings can be summarized as follows 11. General characteristics of the study population ; The population was made up mainly of urban patients who were highly educated. The age was equally distributed. 2. Patients, perceptions and expectations related to illness and hospitalization ; 88.6% of the patients knew about the reason for hospitalization but 64. 5% could state symptoms only. 37.5% recognized the cause of illness. Approximately three fourth of the patients expressed on expectation for early recovery. 60.0% of the patient responses indicated, that they expected less than 10 days of hospitalization. Of the total responses regarding hospitalization, 45.7% were negative about the post -hospitalization expectation, 45.7% expected to return to work. As a result of these findings, we can see that there is a great educational need, a psychological need and environmental need for adaptation to the hospital and a socio- economic need for the post - hospitalization period. 3. Specific basic needs : The physical needs include the problem of getting sufficient sleep (50.0%), difficulty in food intake(47.1%), problems with hospital diet (47.0%), abnormal condition of the skin(44.3%), problems with bowel elimination(35.7%), assistance with bathing(35.7%), pain(30.0%), difficulty in walking(30.0%) , difficulty in seeing(30.0%) problems in urinary elimination(20.0%) , and difficulty in hearing(10.0%), 4. Nursing needs and epidemiological characteristics ; Age distribution was related to the rendition of the mouth but no significant differences were observed statistically with the patients responses to the other nursing history questions according to the epidemiological variables of age, sex, education and residence.

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Frequency Runoff Analysis by Storm Type using GIS and NRCS Method (GIS와 NRCS방법을 이용한 호우형태에 따른 빈도별 유출 분석)

  • Yeon, Gyu-Bang;Jung, Seung-Kwon;Kim, Joo-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.1
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    • pp.119-131
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    • 2003
  • Rainfall-runoff process is under the control of hydrologic parameters having temporal and spatial variety. Accordingly, it is difficult to efficiently deal them since many parameters and various information are required to perform hydrologic simulation. So the purposes of this study is to estimate the runoff volume by frequency using GIS techniques and NRCS method. The analysis of frequency rainfall is analyzed using FARD 2002 program and the result of goodness of fit test show that Log-pearson type III is suitable distribute type for the applied area. TOPAZ program used for the analysis of DEM data examining into geological characteristic. NRCS curve numbers estimated using landuse map and soil map for the estimation of effective rain fall in the basin. The storm Type II and Type III were used as the type for the application of NRCS. The result of application show that the runoff volumes above 80 years frequency in return period have similar patterns regardless of Type II and Type III. In addition, the results of comparison with runoff volumes by frequency in the report of river improvement master plan show that it have similar volumes as the relative errors for them of 80, 100 years frequency are each 7.65%, 5.33%.

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Effects of organic matter sources on nitrogen supply potential in arable land (농경지에서 유기물 시용에 의한 질소 공급 효과)

  • Lee, Ye-Jin;Yun, Hong-Bae;Song, Yo-Sung;Lee, Chang-Hoon;Sung, Jwa-Kyung;Ha, Sang-Keun
    • Korean Journal of Agricultural Science
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    • v.42 no.4
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    • pp.431-437
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    • 2015
  • Recently, assessment of nitrogen balance has been required for environmental agriculture. Nutrient management using organic matters in farmlands has been strongly required as a means of extending resource-cycling agriculture and reduction of nitrogen balance. Organic matters-derived nutrients and soil-available nitrogen should be necessarily considered to manage nutrient balance in soil-plant system. In this study, we reviewed the amount of N supply according to types of organic matter such as livestock compost and green manure in arable land. In case of applied livestock compost in soil, nitrogen mineralization was influenced by nitrogen amount of livestock manure and mixed materials. And nitrogen mineralization of green manure in arable land was influenced by types of crop and return period of green manure because of change of C/N ratio. Also, nitrogen supply by organic matter in arable land can be changed by environmental factors such as temperature, moisture in soil. Therefore, nitrogen supply according to C/N ratio of organic matter and analysis method for estimation of soil nitrogen supply availability should be evaluated to set up the nutrient management model.

Investigation of Fatigue Damage of the Mooring Lines for Submerged Floating Tunnels Under Irregular Waves (불규칙 파랑 중 해중 터널 계류선의 단기 피로 손상 분석)

  • Kim, Seungjun;Won, Deok Hee
    • Journal of Korean Society of Steel Construction
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    • v.29 no.1
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    • pp.49-60
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    • 2017
  • As well as the strength check, fatigue life check is also mainly required for designing mooring lines of the floating structures. In general, forces which induce dynamic structural response significantly affect to fatigue design of the mooring lines. So, waves are mainly considered as the governing loading for fatigue design of the mooring lines. In this study, characteristics of the fatigue damage of the mooring lines for submerged floating tunnels (SFT) under irregular waves are investigated. For this study time domain hydrodynamic analysis is used to obtain motion of the tunnel and tension and stresses of the mooring lines under the specific environmental conditions. Also, the Rainflow-counting method, the Palmgren-Miner's rule, and S-N curves for floating offshore structures presented by DNV recommendation is applied to calculate the fatigue damage due to the fluctuating stresses. Referring to the design plactice of the tendon pipes for TLP (tension-leg platform), which is very similar structural system to SFT, it is assumed that a 100 year return period wave attacks the SFT systems during 48 hours and the fatigue damages due to the environmental loading are calculated. Following the analysis sequence, the effects of the tunnel draft, spacing and initial inclination angle of the mooring lines on the fatigue damage under the specific environmental loadings are investigated.