• 제목/요약/키워드: return rate

검색결과 930건 처리시간 0.028초

An Adaptive USB(Universal Serial Bus) Protocol for Improving the Performance to Transmit/Receive Data (USB(Universal Serial Bus)의 데이터 송수신 성능향상을 위한 적응성 통신방식)

  • Kim, Yoon-Gu;Lee, Ki-Dong
    • Proceedings of the Korea Contents Association Conference
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    • 한국콘텐츠학회 2004년도 추계 종합학술대회 논문집
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    • pp.327-332
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    • 2004
  • USB(Universal Serial Bus) is one of the most popular communication interfaces. When USB is used in an extended range, especially configurating In-home network by connecting multiple digital devices each other, USB interface uses the bandwidth in the way of TDM(Time Division Multiplexing) so that the bottleneck of bus bandwidth can be brought. In this paper, the more effective usage of bus bandwidth to overcome this situation is introduced. Basically, in order to realize the system for transferring realtime moving picture data among digital information devices, we analyze USB transfer types and Descriptors and introduce the method to upgrade detailed performance of Isochronous transfer that is one of USB transfer types. In the case that Configuration descriptor of a device has Interface descriptor that has two AlternateSetting, if Isochronous transfers are not processed smoothly due to excessive bus traffic, the application of the device changes AlternateSetting of the Interface descriptor and requires a new configuration by SetInterface() request. As a result of this adaptive configuration, the least data frame rate is guaranteed to a device that the sufficient bandwidth is not alloted. And if the bus traffic is normal, the algorithm to return to the original AlteranteSetting is introduced. this introduced method resolve the bottleneck of moving picture transfer that can occur in home network connected by multiple digital devices.

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Financial Feasibility Study by Considering Risk Factors for High-Rise Development Project (초고층 개발사업의 리스크 요인을 고려한 재무적 타당성 분석)

  • Chun, Young-Jun;Cho, Joo-Hyun
    • Korean Journal of Construction Engineering and Management
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    • 제18권4호
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    • pp.3-16
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    • 2017
  • Forecasting cash flow is very important but is difficult and complicated to analysis in high-rise development projects. And An expected value which was forecasted on the early stage is likely to fluctuate due to uncertainties around such complicated huge project to consider the probable uncertainty. There are not objectified method which are able to cope with uncertainty of project, and feasibility study based on selected financial analysis does not include liquidity of cash flow. Through such a stochastic method, developer can cope with cash flow fluctuation and set up a financial plan. Also this study is meaningful for laying the foundation for high-rise development project and feasibility study as well as the suitability and accuracy of feasibility study. Analysis showed that NPV and IRR include residential apartments shows surplus revenue as return of apartments offset deficit of hotel and office. Factors influencing the project feasibility for high-rise development project are sales account of $1^{st}$ year and annual vacancy rate of office.

Comparison of Simple Interrupted Approximating Suture with Single Layer Continuous Connell Suture in End-to-end Intestinal Anastomosis of Dogs (개의 단단장문합술에서 단순결절접합봉합과 단층연속코넬봉합의 비교)

  • 이충헌;신영규;정순옥;이채용
    • Journal of Veterinary Clinics
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    • 제18권2호
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    • pp.124-132
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    • 2001
  • The purpose of this study is to know whether single layer continuous connell suture is an acceptable alternative to simple interrupted approximating suture for end-to-end intestinal anastomosis in dogs. Fourteen mixed-breed dogs weighing 2 to 5 kg were allotted to group treated with simple interrupted approximating suture (Group I) and group treated with single layer continuous Connell suture (Group II), each of 7 dogs. All dogs in each suture pattern were compared with time for total operation ad suture elapsed for intestines to anastomose, clinical signs, changing of pre-and postoperative luminal size, status of feces, adhesion at anastomotic site for 14 days after operation. Time for total operation and suture time for intestinal anastomosis were none significant between Group I and Group II, although those in Group II was about 3 minutes shorter than those in Group I, respectively. Group I spent average 47.08${\pm}$11.10 minutes on total operation, 20.97${\pm}$5.54 minutes on suture time for intestinal anastomosis and Group II spent average 44.74${\pm}$7.77 minutes, 17.73${\pm}$3.05 minutes, respectively. All dogs were no special differences in vitality, vomiting, appetite between Group I and Group II for 14 days after operation. All dogs, except one dog in Group I, had showed normal vitality and appetite since 6~8 days after operation. Initial return of fecal passage showed in all dogs before 6 days after operation and thereafter most dogs showed normal feces. According to results, it was thought that all dogs with normal vitality and appetite before 8 days had showed good prognosis. There were no changes of intestinal luminal size in 2 dogs performed Group In and one dog performed Group II between at operation and 14 days after operation. Narrowing rate of intestinal lumen in Group I was average 9.3% of the normal diameter, whereas in Group II, 9.5% of normal diameter. In complications after operation, only one dog in Group I showed intestinal intussusception but the others didn't. Length of adhesion was measured between intestinal anastomotic site and omental graft. Length of adhesion in dogs performed Group II was mostly shorter than that of Group I. Adhesion with proximate intestines occurred in five dogs, which consisted of 3 dogs performed Group I and 2 dogs performed Group II. Concurrently, they had a great length of adhesion between anastomotic site and omental graft. There were no great differences between Group I and Group II about speed of operation, clinical signs, complications such as leakage and stricture. And all dogs performed intestinal anastomosis showed good clinical condition and prognosis. In conclusion, Single layer continuous Connell suture can safely perform an intestinal anastomosis and be an alternative of simple interrupted approximating suture in aspect of speed clinically.

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The Effects of Asian Dust Events on Perceived Symptoms and Behavior of Elementary School Students (황사 발생과 일부 초등학교 학생들의 자각증상 및 행동변화)

  • Lee, Bo-Eun;Wang, Seong-Sik;Park, Hye-Sook;Ha, Eun-Hee;Kwon, Ho-Jang;Lee, Jong-Tae;Cho, Yong-Sung;Park, Young-Soon;Leem, Jong-Han;Hong, Yun-Chul;Cho, Soo-Hun;Pang, Myung-Geol
    • Journal of the Korean Society of School Health
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    • 제16권1호
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    • pp.1-8
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    • 2003
  • Purpose : While there have been growing concerns about the effects of Asian dusts on health, there are few studies for relationship between Asian dusts and health outcome. This study was designed to examine the perceived symptoms and behavior change of children during the Asian Dust events. Methods : We surveyed 459 students at an elementary school in Seoul, Korea from November 20th to 27th 2002. Children with parents were asked to return the completed questionnaires within a week. The questionnaires included the sociodemographic factor, previous respiratory disease, and perceived symptom, hospital visits and behavior change during the Asian dusts. Results : The majority of children reported that they restrained going out and outdoor recreational activity during the Asian dusts. The rate of children who worn the mask was 49% and 47% in second grade and fifth grade, respectively. Regarding the perceived symptom during the Asian dusts, the children in 2nd were more likely to have symptom than 5th and there were significant difference between two groups in cough, asthma symptom, dry cough, phlegm and medication for allergy or asthma symptom. In addition, children who had previous disease were more likely to change behavior in order to prevent the effects of Asian dusts. Conclusions : This study suggested that the younger children and children who had past respiratory disease were susceptible to the effect of Asian dusts. There is a need for providing public information and health education to prevent the impact of Asian dusts on health.

Long-term Impact of Single Rice Cropping System on SOC Dynamics (동일비료장기연용 논에서 토양유기탄소의 변동)

  • Jung, Won-Kyo;Kim, Sun-Kwan;Yeon, Byung-Yul;Noh, Jae-Seung
    • Korean Journal of Soil Science and Fertilizer
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    • 제40권4호
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    • pp.292-297
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    • 2007
  • Global warming and climate changes have been major issues for decades andvarious researches have reported their impact on our environment. According to recent researches, increased carbon dioxide ($CO_2$) concentration in the atmosphere is considered as a dominant contributor to global climate changes and thus numerous researches were conducted to control $CO_2$ concentration in the atmosphere. Soil management practices, such as reducing tillage intensity, returning plant residues, and enhancing cropping system have recommended for restoring organic carbon into the soils effectively. However, few studies on soil carbon sequestration have reported for Korean paddy soils. Therefore, evaluation of soil organic carbon (SOC) dynamics in the long-term single rice cropping system is essential in order to find out potential capacity of paddy field as a carbon sink source. The objective of this research was to evaluate SOC dynamics on the long-term single rice cropping system. Research was conducted in the research farm at National Institute of Agricultural Science and Technology, Rural Development Administration, Suwon. Long-term phosphorus and potassium fertilization and lime application didn't significantly affect on SOC compared to controls. We found that SOC contents were increased continually at the long-term composting plots with enhanced rate of carbon storage. In conclusion, continuous incorporation of plant residues (i.e., composting) is recommended to effectively sequester soil carbon for Korean paddy soils. This result implies that continuous composting in a paddy field may contributenot only for increasing SOC in the soils but also for mitigating global warming through reducing carbon dioxide emission into atmosphere. Therefore, we recommend that a strategy or policy measures to encourage farmers to return plant residues continuously for mitigation of global warming as well as soil fertility is being developed.

Effect of Temporary Anterior Positioning Splint Using Putty Impression Material on Acute Closed Lock (급성 과두 걸림의 치료에서 퍼티 고무 인상재로 제작한 임시 전방위치장치의 적용)

  • Song, Ji-Hee;Kim, Ji-Hyun;Kwon, Jeong-Seung;Ahn, Hyung-Joon
    • Journal of Oral Medicine and Pain
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    • 제37권4호
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    • pp.221-225
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    • 2012
  • Disc dislocation without reduction, as known as closed lock, is a clinical condition in which the disc is dislocated from the condyle and does not return to normal position during condylar movement When the condition of disc dislocation without reduction is acute, the initial therapy should include an attempt to reduce or recapture the disc by manual manipulation. When patients report a history of being locked for 1 week or less, manual manipulation is usually successful. In patients with a longer history, success rate tends to decrease rapidly. If the disc has been successfully recaptured, placing an anterior positioning appliance is recommended to prevent clenching on the posterior teeth, which would likely redislocated the disc. But it is hard to make an appliance immediately in the clinic because it takes too much time. And making an appliance using self-curing acrylic resin is not very popular because of its discomfort by odor and working time. Also, if the patient has resin allergy or is under orthodontic treatment, or if it is impossible to control behavior of the patient, it has been restricted to make an appliance immediately. Therefore, to supplement this disadvantages, we tried to confirm about successful short term use of temporary anterior positioning splint made by using putty impression material after manual manipulation in this study.

Development of a GIS Application Model for Analyzing Site-Specific Suitability and Investment Efficiency of Major Plantation Species (주요 조림수종의 적지 판정 및 투자효율성 분석을 위한 GIS 응용모델의 개발)

  • Kim, Eui-Gyeong;Kim, Hyung-Ho;Chung, Joo-Sang
    • Journal of the Korean Association of Geographic Information Studies
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    • 제9권2호
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    • pp.1-10
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    • 2006
  • The objective of this study was to develop a GIS application model for analyzing site-specific suitability and investment efficiency of major plantation tree species. The model was designed to choose the best plantation species in terms of both potential stand growth and investment efficiency. Site index and IRR were used as the criteria for the potential of stand growth and investment efficiency, respectively. In the model, the conditions of forest stand management and site index are estimated as the function of site-environmental factors extracted by a series of spatial analyses of digital maps of FGIS. Based on site index values of tree species, the model screens out all the high potential tree species, in terms of stand growth, as the candidates for species selection and, then, calculates IRR for managing plantation forest stands for all the candidate tree species. The tree species of the highest IRR would be chosen as the one possessing the highest potential in terms of stand growth and profit. The model was applied to a case study for analyzing the site-specific suitability of 6 tree species in Taehwa University Forest of Seoul National University and the results are given in this paper.

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A Study on a Ku-Band High Power and High Efficiency Radial Combiner (Ku 대역 고출력 고효율 Radial Combiner에 대한 연구)

  • Yun, Song-Hyun;Kim, Si-Ok;Lee, Su Hyun;Lim, Byeong-Ok;Lee, Bok-Hyung;Jeon, Yong-Kyu;Kim, Hyun-Kyu;Yoo, Young-Geun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • 제28권5호
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    • pp.400-409
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    • 2017
  • We have studied a combiner that can withstand high power while minimizing insertion loss in high frequency band. In particularly, because the output power that can be output per unit elements is much lower in the Ku band and above than in the low frequency band, it is necessary to combine many semiconductor elements in order to make a high power SSPA. A planar combiner such as a microstrip, as the number of elements to be combined increases, the insertion loss increases proportionally, resulting in a reduction in the overall system efficiency and an increase heating value also. The planar combiner also have some problems due to the low power handling rate. To improve these problems, we proposed a Cavity Radial Combiner. A Ku band 16-way Cavity Radial Combiner was fabricated and measured. As a result, it was tested 14dB return loss and over 94.5 % output combining efficiency in design band.

A Study on the Academic Dropout of College Students (대학생의 중도탈락에 관한 연구(D대학 중심))

  • Lee, Jae-Do
    • Journal of the Korea society of information convergence
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    • 제1권1호
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    • pp.47-54
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    • 2008
  • This study analyzed the status and causes for the dropouts of college based on the survey conducted among 14,210 freshmen attending D College, other than the supernumerary special selection, from 2001 through 2005. A significant difference was shown in all items of general characteristics. The dropout rate of women, generally selected and general highschool graduated were higher than for men, specially selected and special high school graduated, respectively. The most dropouts were due to Not Return(40.16%), followed by Unenrolled(32.98%), Voluntary Leave(26.05%) and Expelled(0.81%) in order. In the distribution of the central tendency values measured from the entire subjects, the high school records and the days of absence showed a positive skewness, while the college records showed a negative skewness with the data mostly around a higher grade. The standard deviation indicating that the dropouts got the scores higher than those of the continuing students demonstrated that there was relatively insignificant difference in scores between two groups. It was demonstrated that both the high school records and the days of absence affected the dropout. The lower the high school records were, and the more the days of absence were, the more influence both items had on the dropout. The influence degree of each item was similar. Lower the scores were in terms other than the first term in the freshmen year, the more influence it had on the dropout. The most dropouts were influenced by the scores of the freshmen year, followed by the credits of the second term, the scores of the first term, the scores of the second term, and the credits of the first term in the freshmen year. Among the general characteristic items, the most dropouts were influenced by the course of study, followed by the gender. The effect of other items was insignificant.

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Extremal Dependence in Asia Pacific Exchange Markets (EVT-Copula 모형을 이용한 아시아 외환시장 간 극단적 의존성에 관한 연구)

  • Kim, Tae-Hyuk;Zhao, Hui-Jing
    • The Korean Journal of Financial Management
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    • 제23권1호
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    • pp.193-225
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    • 2006
  • The purpose of this paper is to analyze contagion in Asian foreign exchange markets using Extreme Value Theory and Copula. Our application deals with asymptotic dependence of daily exchange rate return for a sample of eight countries over period 1997.1.1-2005.4.13. The empirical results are summarized as follows. Firstly, Gumbel Copula is a good model to our data according to the value of AIC. Secondly, the extremal dependence between East Asian crisis countries became lower in the post crisis period than the crisis period. Thirdly, It seemed that high extremal dependence exists between East Asian countries with Singapore. Fourthly, the tail dependence between Indonesia, Malaysia, Thailand, Philippine became higher in the crisis period than the total period and post crisis period. Fifthly, the fact that the extremal dependence between Korea and Indonesia, Malaysia, Thailand, Philippine did not increase during the Asian Financial Crisis showed that the contagion effect was not the reason of the Korea's Fiancial Crisis. Sixthly, the extremal dependence between Asian exchange markets was not very high while comparing with the European exchange markets.

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