• 제목/요약/키워드: Present worth

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삼림경영계획(森林經營計劃)을 위한 새로운 접근법(接近法) : 퍼지 다목표선형계획법(多目標線型計劃法) (A New Approach for Forest Management Planning : Fuzzy Multiobjective Linear Programming)

  • 우종춘
    • 한국산림과학회지
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    • 제83권3호
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    • pp.271-279
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    • 1994
  • 본(本) 논문(論文)에서는 인공조림임분경영계획(人工造林林分經營計劃) 문제를 해결하기 위하여 임업(林業)에서 최근 새롭게 적용되고 있는 퍼지 다목표(多目標) 선형계획법(線型計劃法)을 소개한다. 우선 퍼지 집합이론(集合理論)이 간략하게 설명되고 퍼지 선형계획법(線型計劃法) 및 퍼지 다목표 선형계획법이 개념적으로 소개된다. 그 다음 연구대상지역의 자료를 분석하여 표준적(標準的) 선형계획(線型計劃)모델이 구성되고 이 모델의 컴퓨터 계산에 의해 4개의 목재가격(木材價格) 범위에 대한 최적해(最適解)(순현재가(純現在價))가 각각 계산된다. 이 선형계획모델은 불확실한 4개의 목재가격정보를 조정하기 위해서 퍼지 다목표(多目標) 선형계획(線型計劃)모델로 재구성된다. 그리고 이 퍼지 모델의 계산에 의해 절충최적해(折衷最適解)가 얻어지게 된다. 4개의 목재가격 범위에 대해 얻어진 4개의 최적해와 하나의 절충최적해가 비교(比較)되고 논의(論議)된다.

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린(Lean) 개념을 소프트웨어 개발 방법에 적용하기 위한 사례 연구: 낭비 제거의 가시화를 중심으로 (How to Implement 'Lean' Principles into Software Development Practice?: Visualization of Delays and Defects)

  • 황순삼;김성근
    • 경영정보학연구
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    • 제13권1호
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    • pp.61-74
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    • 2011
  • 소프트웨어 산업은 아직도 뿌리깊은 문제에 시달리고 있다. 어떻게 보면, 제조업과 같은 보다 성숙한 산업의 모범사례로부터 뭔가를 배워야 할 지 모른다. 제조업에서의 '린' 원칙을 소프트웨어 개발에 적용하는 것도 한 방안일 수 있다. 소프트웨어공학 문헌에서 이런 '린' 원칙은 시도해 볼만 한 것으로 언급되었다. 그러나 이들 원칙을 실제 어떻게 적용할 수 있을 가에 대한 구체적 방안을 제시한 연구는 별로 없었다 본 연구는 '린' 원칙을 소프트웨어 개발에 적용하는 방안을 제시하고자 한다. 이 방안의 핵심은 낭비제거라는 린의 관점을 구체화하기 위하여 프로젝트에서의 리드 타임과 결함을 누적 흐름도(Cumulative Flow Diagram)을 통해 관리하는 방법이다. 또한 이 방안을 실제 프로젝트 사례에 적용함으로써 타당성을 검증하고 적용 방법에 대한 이해를 돕고자 하였다.

The Etiology and Treatment of the Softened Phallus after the Radial Forearm Osteocutaneous Free Flap Phalloplasty

  • Kim, Seok-Kwun;Kim, Tae-Heon;Yang, Jin-Il;Kim, Myung-Hoon;Kim, Min-Soo;Lee, Keun-Cheol
    • Archives of Plastic Surgery
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    • 제39권4호
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    • pp.390-396
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    • 2012
  • Background The radial forearm osteocutaneous free flap is considered to be the standard technique for penile construction. One year after their operation, most patients experience a softened phallus, so that they suffer from difficulties in sexual intercourse. In this report, we present our experience with phalloplasty by radial forearm osteocutaneous free flap, as well as an evaluation of the etiology and treatment of the softened phallus. Methods Between March 2005 and February 2010, 58 patients underwent phalloplasty by radial forearm osteocutaneous free flap. Most of their neophallus had been softened subjectively and among them, 12 patients who wanted correction were investigated. We performed repetitive fat injection, artificial dermis grafting, silicone rod insertion, and rib bone with cartilaginous tip graft. Physical examination, plain radiograph, computed tomography, bone scintigraphy, and satisfaction scores were investigated. Results Most of the participants' penises have been softened after phalloplasty, and the skin elasticity had been also decreased. On plain radiograph, the distal end of the bone was self-rounded; however, the bone shape of the neophallus had no significant interval changes or resorption. Computed tomography showed equivocal density of cortical bone. On bone scintigraphy, the bone metabolism was active at 3 months postoperatively, and remained active 9 years postoperatively. Conclusions The use of a rib bone with cartilaginous tip graft could be an option for improvement of the softened phallus. Silicon rod insertion is also worth considering for rigidity of the softened phallus. Decreased rigidity due to soft tissue atrophy could be alleviated with repeated fat injection and artificial dermis grafting.

민간병원의 유동성 관련요인 분석 (Liquidity Determinants of Private Hospitals in Korea)

  • 최만규;이윤석;이윤현
    • 보건행정학회지
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    • 제12권4호
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    • pp.1-17
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    • 2002
  • This study was attempted to identify the liquidity trends and determinants of private hospitals in Korea different. Data used in this study were collected from 98 hospitals with complete general data of present conditions as well as financial statements(balance sheets, income statements). They were chosen from hospitals that passed the standardization audit undertaken by the Korean Hospital Association from 1996 to 2000 for the purpose of accrediting training hospitals. The dependent variables in this study were used current ration and quick ratio as a proxy indicator for liquidity. The independent variables were ownership type, hospital type, location, bed size, period of establishment, short-term liabilities to total assets, long-term liabilities to total assets, borrowings to total assets, fixed asset ration, net profit to total assets, operating margin to gross revenue, growth rate of net worth to total assets, total asset turnover, and business risk(volatility of profit). The major findings of this study were as follows. Trends of liquidity(current ratio, quick ratio) had been continuously decreased. Especially, There were very distinct decreasing trends of personal hospitals and less than 300beds, which weakened liquidity. The factors had significant effect on current ratio were short-term debt to total assets(-), fixed asset ratio(-), business risk(+). High short-term debt to total assets, high fixed asset ratio and high business risk significantly decreased in liquidity. The factors that significantly affected on quick ratio were short-term debt to total assets(-), borrowings to total assets(+), fixed asset ratio(-), business risk(+).

Doxorubicin Inhibits the Production of Nitric Oxide by Colorectal Cancer Cells

  • Jung, In-Duk;Lee, Jang-Soon;Yun, Seong-Young;Park, Chang-Gyo;Han, Jeung-Whan;Lee, Hyang-Woo;Lee, Hoi-Young
    • Archives of Pharmacal Research
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    • 제25권5호
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    • pp.691-696
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    • 2002
  • Doxorubicin (DOX) is an active and broad spectrum chemotherapeutic agent. Increased inducible nitric oxide synthase (NOS) expression and/or activity have been reported in several human tumors. While the relationship between DOX treatment and the enzymatic activity of endothelial NOS has been well characterized, little is known about the effects of DOX on the expression of iNOS in human cancer cells. In the present study, we characterized the effects of DOX on the nitric oxide (NO) production by colorectal cancer cells, DLD-1. IFN-${\gamma}$/IL-1$\beta$ (CM) increased the production of NO, whereas pretreatment of DOX inhibited the production of NO in response to CM in a dose dependent manner. The increased expressions of iNOS mRNA and protein by CM were completely blocked by DOX without affecting the iNOS mRNA stability. However, DOX activated nuclear factor-kB (NF-kB) in response to CM. Furthermore, the expression of inhibitor kB$\alpha$ was reduced by DOX in a dose dependent manner. Collectively, DOX inhibited the production of NO by DLD-1 cells, which is not linked to well known transcription factor, NF-kB. Therefore, further studies on the possible mechanisms of inhibitory effects of NO production by DOX would be worth pursuing.

치태제거 및 치은염증에 대한 실리콘 칫솔의 효과 (The Effect of Silicone Toothbrush on Plaque Control and Gingival Inflammation. A Comparative Clinical Study)

  • 정예진;김창성;서종진;조규성;채중규;김종관;최성호
    • Journal of Periodontal and Implant Science
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    • 제30권4호
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    • pp.911-923
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    • 2000
  • A comparative clinical study on the ordinary toothbrush($Buttler^{(R)}$, America) and the silicone toothbrush($Jefe^{(R)}$, Korea) was performed. The volunteers who took part in this study were students of Dental college of Yonsei University and patients attending Dental Hospital of Yonsei University. They were classified into two group, control and experimental group. Control group brushed with nylon toothbrush and experimental group did with silicone toothbrush under the researcher's guidances. Volunteers were examined on Plaque Index(PI), Gingival Index(GI), Probing Depth(PD), Bleeding on Probing(BP) and Recession(R) at base line, 1st. week, 2nd. week and 4th. week. According to the results, both group have the tendency of improvement in the degrees of GI, PI and the improvement degree of GI of both group has the significant differences from base line statistically, and there are not statistically significant differences between the silicone and nylon group in respect of PI, GI values. So based on the present study, it could be carefully ascertained that the silicone toothbrush has similar effect with nylon toothbrush in respect of PI and GI. If it is sure that the silicone toothbrush is seldom abrasive and possibly enough to massage the gingiva, this new brush is worth to be recommended by the dentists.

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Nanostructured Metal Organic Framework Modified Glassy Carbon Electrode as a High Efficient Non-Enzymatic Amperometric Sensor for Electrochemical Detection of H2O2

  • Naseri, Maryam;Fotouhi, Lida;Ehsani, Ali
    • Journal of Electrochemical Science and Technology
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    • 제9권1호
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    • pp.28-36
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    • 2018
  • Metal-organic frameworks have recently been considered very promising modifiers in electrochemical analysis due to their unique characteristics among which tunable pore sizes, crystalline ordered structures, large surface areas and chemical tenability are worth noting. In the present research, $Cu(btec)_{0.5}DMF$ was electrodeposited on the surface of glassy carbon electrode at room temperature under cathodic potential and was initially used as the active materials for the detection of $H_2O_2$. The cyclic voltammogram of $Cu(btec)_{0.5}DMF$ modified GC electrode shows distinct redox peaks potentials at +0.002 and +0.212 V in 0.1 M phosphate buffer solution (pH 6.5) corresponding to $Cu^{(II)}/Cu^{(I)}$ in $Cu(btec)_{0.5}DMF$. Acting as the electrode materials of a non-enzymatic $H_2O_2$ biosensor, the $Cu(btec)_{0.5}DMF$ brings about a promising electrocatalytic performance. The high electrocatalytic activity of the $Cu(btec)_{0.5}DMF$ modified GC electrode is demonstrated by the amperometric response towards $H_2O_2$ reduction with a wide linear range from $5{\mu}M$ to $8000{\mu}M$, a low detection limit of $0.865{\mu}M$, good stability and high selectivity at an applied potential of -0.2 V, which was higher than some $H_2O_2$ biosensors.

전력회사와 발전사업자 측면에서 도서지역용 마이크로그리드의 경제성평가 알고리즘 (Economic Evaluation Algorithm of Island Micro-grid for Utility and Independent Power Producer)

  • 남양현;이후동;김유림;마리토;김미영;노대석
    • 전기학회논문지
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    • 제66권7호
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    • pp.1032-1038
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    • 2017
  • Recently, regulation on carbon emissions has been strengthened according to the new climate change convention (COP21) held in Paris, and then Korea has decided to reduce CO2 emissions by 37% until 2030. As one of countermeasures, the government has energetically performed demonstration projects of island micro-grid including solar power, wind power and energy storage system. However, in order to smoothly introduce island micro-grid, it is a critical issue to carry out the economic evaluation for power utility aspect and independent power producer aspect. Therefore, this paper proposes economic evaluation algorithms of island micro-grid which are based on the present worth method, considering cost and benefit factors in the aspect of both sides. Firstly, in case of power utility this paper proposes algorithm to estimate a period of return on investment according to the introduction capacity of distributed generators replacing diesel generator. And also, in case of independent power producer, this paper proposes evaluation algorithm to estimate weighting factor of SMP and benefit rate based on break-even point related with cost and benefit. From a case study result on real island micro-grid model, it is confirmed that proposed algorithms are useful and practical for the economic evaluation of island micro-grid.

스토리텔링을 활용한 '태양계와 별' 단원 수업이 과학개념 및 과학학습 동기에 미치는 효과 (The Effects of 'Solar System and Star' Using Storytelling on Science Concept and Science Learning Motivation)

  • 김윤경;이용섭
    • 대한지구과학교육학회지
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    • 제9권1호
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    • pp.97-105
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    • 2016
  • The purpose of this study was to examine the effects of storytelling skill on science concept and science learning motivation. For this study the 5 grade, 2 class was divided into a research group and a comparative group. The class was pre-tested in order to ensure the same standard. The research group had the science class with storytelling skill, and the comparative group had the class of the teacher centered lectures on 11 classes in 8 weeks. The storytelling skill was focused on set the astronomical target wants to set up a story, through the small group discussion, present subject of the story, set the protagonist of the story for smooth configuration of the story, in order to smooth the flow of the story, make up a story around a hero, to make a clear story, decorated with pictures, shapes, graphs, etc, group story, complete with an astronomical(saints) in storytelling. To prove the effects of this study, science concept was split up according to knowledge, inquiry, attitude. Also, science learning motivation consisted of assignment is worth, learning beliefs about control, self efficacy. The results of this study are as follows. First, using storytelling skill was effective in science concept. Second, using storytelling skill was effective in science learning motivation. Also, after using storytelling skill was good reaction by students. As a result, the elementary science class with storytelling skill had the effects of developing science concept and science learning motivation. It means the science class with storytelling skill has potential possibilities and value to develop science concept and science learning motivation.

Asunaprevir, a Potent Hepatitis C Virus Protease Inhibitor, Blocks SARS-CoV-2 Propagation

  • Lim, Yun-Sook;Nguyen, Lap P.;Lee, Gun-Hee;Lee, Sung-Geun;Lyoo, Kwang-Soo;Kim, Bumseok;Hwang, Soon B.
    • Molecules and Cells
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    • 제44권9호
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    • pp.688-695
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    • 2021
  • The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a global health concern. Various SARS-CoV-2 vaccines have been developed and are being used for vaccination worldwide. However, no therapeutic agents against coronavirus disease 2019 (COVID-19) have been developed so far; therefore, new therapeutic agents are urgently needed. In the present study, we evaluated several hepatitis C virus direct-acting antivirals as potential candidates for drug repurposing against COVID-19. Theses include asunaprevir (a protease inhibitor), daclatasvir (an NS5A inhibitor), and sofosbuvir (an RNA polymerase inhibitor). We found that asunaprevir, but not sofosbuvir and daclatasvir, markedly inhibited SARS-CoV-2-induced cytopathic effects in Vero E6 cells. Both RNA and protein levels of SARS-CoV-2 were significantly decreased by treatment with asunaprevir. Moreover, asunaprevir profoundly decreased virion release from SARS-CoV-2-infected cells. A pseudoparticle entry assay revealed that asunaprevir blocked SARS-CoV-2 infection at the binding step of the viral life cycle. Furthermore, asunaprevir inhibited SARS-CoV-2 propagation in human lung Calu-3 cells. Collectively, we found that asunaprevir displays broad-spectrum antiviral activity and therefore might be worth developing as a new drug repurposing candidate for COVID-19.