• Title/Summary/Keyword: Open and Closed

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Closed-code-conversion: Transforming Open Code Multi-staged Programs into Closed Ones (다단계 프로그램에서 프로그램 생성 단계의 자유변수 제거)

  • Eo, Hyun-Jun;Yi, Kwang-Keun
    • Journal of KIISE:Software and Applications
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    • v.36 no.3
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    • pp.244-251
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    • 2009
  • We present a transformation which converts open-code multi-staged programs into closed ones. Staged computation, which explicitly divides a computation into separate stages, is a unifying framework for existing program generation systems. Because a multi-staged program generates another program, which can also generate a third program and on, the implementation of a multi-staged language is not straightforward. Dynamic binding of (lexically free) variables in code also makes the implementation of a multi-staged language hard. By converting each code into code of function which takes environment for free variables as its argument and giving an actual environment at the code-composition site, we can transform a open-code program into a closed-code one. Combining with Davies and Pfenning's method, our closed-code-conversion enables the implementation of the unstaged language to be useful for executing multi-staged programs. We also prove the correctness of our conversion: the converted program is equivalent to the original program, and the converted program does not have open code.

A Study on the Effect of Open and Closed Room Doors on Apartment Ventilation Characteristics (공동주택에서 각 실 문의 개폐에 따른 환기 특성 연구)

  • Choi, Im-Kyoo;Kim, Young-Il;Chung, Kwang-Seop
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.469-474
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    • 2008
  • The objective of this study is to propose basic design guidelines for more effective air ventilation system in apartments. It is well known that ventilation depends on whether the room doors are open or closed as well as people's living patterns. This study considers 84 ㎡-sized apartment which has extended living room without balcony. Ventilation of bathroom and kitchen is not considered. The height of the building, external air pressure and air infiltration through the windows are also neglected. The regulation on indoor air quality made it mandatory that the air change per hour be more than 0.7. Four models are suggested to study the effect of open and closed doors. Models 1 and 3 are open door types and models 2 and 4 are closed door types. The open types have 50 mm hole near the top of the door to substitute exhaust outlet. The ventilation effectiveness was evaluated by 3-dimensional numerical simulation using finite volume method by a commercial software. This work compares air flow, temperature of air, age of air and the efficiency of ventilation of apartments with wooden doors of bedroom 1 and 2, which are open or closed.

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Impact of Sluice Gates at Stream Mouth on Fish Community (하구의 배수갑문 설치 유무가 어류군집에 미치는 영향)

  • Kim, Jun-Wan;Kim, Kyu-Jin;Choi, Beom-Myeong;Yoon, Ju-Duk;Park, Bae-Kyung;Kim, Jong-Hak;Jang, Min-Ho
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.49-59
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    • 2022
  • Total of 325 estuaries in Korea were surveyed to analyze the effect of presence of sluice gate on the estuary environment and fish community from 2016 to 2018. Fish community in closed and open estuaries showed differences generally, and the relative abundance (RA) of primary freshwater species in the closed and migratory species in the open estuaries were high. The result of classifying species by habitat characteristics in closed and open estuaries showed similar tendencies at the estuaries of south sea and west sea. The relative abundances of primary freshwater species in the closed estuaries at the estuaries of south sea and west sea were the highest, but estuarine and migratory species were high in both closed and open estuaries at the estuaries of east sea. Primary freshwater species showed higher abundances in the closed estuaries with reduced salinity due to blocking of seawater since they are not resistant to salt. However, primary freshwater species in open estuaries at east sea was higher than that of the closed estuaries, which is considered to be the result of reflecting the characteristics (tide, sand bar, etc.) of the east sea. Korea Estuary Fish Assessment Index (KEFAI) was showed to be higher at open estuaries than closed in all sea areas (T-test, P<0.001), the highest KEFAI was observed in closed estuaries at south sea, and open estuaries in east sea. Fish community of closed and open estuaries in each sea areas showed statistically significant differences (PERMANOVA, East, Pseudo-F=3.0198, P=0.002; South, Pseudo-F=22.00, P=0.001; West, Pseudo-F=14.067, P=0.001). Fish assemblage similarity by sea areas showed a significant differences on fish community in closed and open estuaries at east sea, south sea, and west sea (SIMPER, Group dissimilarity, 85.85%, 88.36%, and 88.05%). This study provided information on the characteristics and distribution of fish community according to the types of estuaries. The results of this study can be used as a reference for establishing appropriate management plans according to the sea areas and type in the management and restoration of estuaries for future.

Surgical Treatment of Mitral Valvular Disease (승모판막질환의 수술)

  • 이인성
    • Journal of Chest Surgery
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    • v.12 no.2
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    • pp.127-134
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    • 1979
  • During the 4 years period to be reported, 34 operations were performed on the mitral valve in the department of Thoracic and cardiovascular surgery, Korea University hospital, from Aug. 1975 to April 1979. At the first 1-year period, the closed technique was used in 12 patients. After that, open-heart surgery was used routinely; 8 patients had open mitral commissurotomy and 14 patients had valve replacement. There were 18 men and 16 women with sex ratio of 1.1: 1. The age of the patients varied widely from 18 years of the youngest to 46 years of the oldest-average aged of 32.5 years. All had symptoms and the mean duration of symptoms was 6 years and 1 month. Preoperative atrial fibrillation was 47% and embolizations were in 3 of 34 patients. The operative mortality was none for the closed and 14% for the open technique combined rate of 9 per cent which were valve thrombosis, brain embolism and left pulmonary vein rupture in deauriculization. But surviving patients undergoing open heart surgery enjoyed symptomatic benefits comparable to these of the patients of closed.

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An Experimental Study on the Characteristics for Open-Tube and Closed-Tube Thermoacoustic Effects (2)- The 2nd, 3rd Harmonic (개방관과 밀폐관의 열음향 효과에 관한 하모닉 특성 연구(2) - 2차, 3차 하모닉)

  • 송규조;박종호;이성노
    • Progress in Superconductivity and Cryogenics
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    • v.4 no.1
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    • pp.135-139
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    • 2002
  • In this study, the experimental open-tube and close-tube thermoacoustic apparatuses were built. In order to determine the optimum length of resonant tube and the optimum length of stack, the resonant characteristics of thermoacoustic apparatuses were investigated, The length of resonant tube varies from 400mm to 850mm. The experimental frequency varies from 100Hz to 1000Hz. In case of the second and third harmonics, the maximum temperature difference of open-tube thermoacoustic apparatus is 53$^{\circ}C$ (resonator length: 400mm) and the maximum temperature difference of closed-tube thermoacoustic apparatus is 51$^{\circ}C$ (resonator length: 500mm). In the open-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 55%, 69% in the resonant tube and in the closed-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 41%, 50% in the resonant tube.

Comparisons of Ion Balance, Fruit Yield, Water, and Fertilizer Use Efficiencies in Open and Closed Soilless Culture of Paprika (Capsicum annuum L.)

  • Ko, Myat Thaint;Ahn, Tae In;Son, Jung Eek
    • Horticultural Science & Technology
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    • v.31 no.4
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    • pp.423-428
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    • 2013
  • Although closed soilless culture is useful for saving water and fertilizers with minimizing environmental pollution, adequate management of nutrient solutions is still not stabilized in greenhouse cultivation. In order to investigate the problems occurred in closed soilless culture of Paprika (Capsicum annuum L., cv. Fiesta), we compared ion balance, fruit yield, and the water and fertilizer use efficiencies in the closed system with those in the open system. The plants were grown in rockwool culture with a nutrient solution of EC $2.5dS{\cdot}m^{-1}$. After 4 weeks of treatment, individual ratio of $NO{_3}^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ to total ion concentrations ($meq{\cdot}L^{-1}$) decreased from the initial value, especially the biggest decrement was observed in $K^+$, and on the other hand, $SO{_4}^{2-}$, $Cl^-$, and $Na^+$ were accumulated in the closed system. Yields after four-time harvests were 19% higher in the open system than in the closed system. Total volume of water used per unit area ($m^2$) in the open system was 20% higher, but the total water use per fruit was not significantly different between the two systems, while t total fertilizer use per fruit was 78% higher in the closed system. Amount of marketable fruits was not significantly different between the two systems. We concluded that the increase in $K^+$ supply and the replenishment of recycled nutrient solution every four weeks were required for preventing the imbalance or depletion of nutrients in the close soilless culture of paprika plants to get more balanced nutrient composition during whole cultivation period.

Dynamic Modelling of Planar Mechanisms Using Point Coordinates

  • Attia, Hazem-Ali
    • Journal of Mechanical Science and Technology
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    • v.17 no.12
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    • pp.1977-1985
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    • 2003
  • In the present study, the dynamic modelling of planar mechanisms that consist of a system of rigid bodies is carried out using point coordiantes. The system of rigid bodies is replaced by a dynamically equivalent constrained system of particles. Then for the resulting equivalent system of particles, the concepts of linear and angular momentums are used to generate the equations of motion without either introducing any rotational coordinates or distributing the external forces and force couples over the particles. For the open loop case, the equations of motion are generated recursively along the open chains. For the closed loop case, the system is transformed to open loops by cutting suitable kinematic joints with the addition of cut-joints kinematic constraints. An example of a multi-branch closed-loop system is chosen to demonstrate the generality and simplicity of the proposed method.

Implementation, Security, and Usability Analysis of Accredited Certificate-based Internet Banking (공인인증서 기반 인터넷 뱅킹의 구현, 보안성, 그리고 편의성 분석)

  • Park, Hye-Seung;Lee, Jae-Hyup;Park, Seung-Chul
    • Journal of Internet Computing and Services
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    • v.18 no.4
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    • pp.69-78
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    • 2017
  • We expect that the accredited certificate-based open banking, which is actively deployed in recent times, will solve the Galapagosization problem of the existing accredited certificate-based closed banking by supporting standard communication protocol and web compatibility. However, it is questionable how much the open banking will answer the security and usability problems of the existing closed banking. This paper is focused on analyzing the differences between the existing closed banking and the open banking, and then evaluates how much the security and usability problems of the existing closed banking are resolved by the open banking. The study firstly analyzes the security vulnerabilities raised in the process of providing closed banking services for the past 15 years or more, the countermeasures applied to enhance security, and the convenience impact of countermeasures. And then, the security and convenience of the open banking is inferred by analyzing the implementation difference between the closed banking and the open banking. The paper also briefly discusses how to improve the open banking to resolve the remaining problems of the open banking.

Some Fuzzy Closed Sets and Fuzzy Approximately Continuous Mappings

  • Ahn, Y.S.;Hur, K.;Ryou, J.H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.2
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    • pp.184-189
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    • 2001
  • First, we find the characterization of fg-closure of a fuzzy set. Second, we study some properties of frg-closeds and fg-continuous mappings. Finaly, we introduce the concept of a fuzzy approximately continuous mapping and study its properties.

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