• Title/Summary/Keyword: MODELS

Search Result 41,187, Processing Time 0.081 seconds

Establishment of the Heart Failure Model by Coronary Artery Ligation in Sheep (양에서 관상동맥 결찰에 의한 심부전 모델의 확립)

  • 나찬영;홍장수;박정준;김원곤;강문철;서정욱
    • Journal of Chest Surgery
    • /
    • v.35 no.1
    • /
    • pp.1-10
    • /
    • 2002
  • Background: Despite the relatively high mortality rates in the chronic heart failure model induced by coronary artery ligation are relatively high, this model has been a subject of continuos research because of its clinical correlation. Chronic heart failure model of large-sized animals is very useful to analyse mechanical or biological effects on circulatory system which is difficult in small-sized animals. The purpose of this study is to establish the heart failure model by coronary artery ligation in sheep. Material and Method: Among 9 Corridale sheep, the homonymous artery and the diagonal branch were ligated simultaneously in 2 sheep and remaining 7 sheep were assigned to successive ligation of both arteries at an interval of 1 hour. Both coronary arteries were ligated from the point 40% proximal to the apex of the heart. Hemodynamic and echocardiographic parameters were analyzed before the ligation of the coronary artery, after the ligation of the homonymous artery, and after additional ligation of the diagonal branch. The experimental animals were sacrificed after 2 or 3 months of growth and histopathologic studies were performed Result: Immediate postoperative death occurred in the 2 sheep that had received simultaneous ligation of the homonymous artery and diagonal branch. On the other hand, all the 7 sheep that were lifated in succession were survived up to 3 months. Arterial pressure was sifnificantly decreased immediately after ligation of the homonymous artery(p<0.05), and the cardiac output was decreased and pulmonary capillary wedge pressure was increased after further ligation of the diagonal branch(p<0.05). Central venous pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, left ventricular end-diastolic dimension and end-systolic dimension were markedly increased 3 months after ligation of coronary arteries. Anteroseptal akinesia or dyskinesia was developed after the ligation of coronary arteries. Histopathologic study revealed we]1-demarcated ischemic area of fibrosis. Conclusion: Using methods of successive ligation of the homonymous artery and diagonal branch, chronic heart failure model could be reliably established in sheep.

A Product Model Centered Integration Methodology for Design and Construction Information (프로덕트 모델 중심의 설계, 시공 정보 통합 방법론)

  • Lee Keun-Hyoung;Kim Jae-Jun
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • autumn
    • /
    • pp.99-106
    • /
    • 2002
  • Researches on integration of design and construction information from earlier era focused on the conceptual data models. Development and prevalent use of commercial database management system led many researchers to design database schemas for enlightening of relationship between non-graphic data items. Although these researches became the foundation fur the proceeding researches. they did not utilize the graphic data providable from CAD system which is already widely used. 4D CAD concept suggests a way of integrating graphic data with schedule data. Although this integration provided a new possibility for integration, there exists a limitation in data dependency on a specific application. This research suggests a new approach on integration for design and construction information, 'Product Model Centered Integration Methodology'. This methodology achieves integration by preliminary research on existing methodology using 4D CAD concept. and by development and application of new integration methodology, 'Product Model Centered Integration Methodology'. 'Design Component' can be converted into digital format by object based CAD system. 'Unified Object-based Graphic Modeling' shows how to model graphic product model using CAD system. Possibility of reusing design information in latter stage depends on the ways of creating CAD model, so modeling guidelines and specifications are suggested. Then prototype system for integration management, and exchange are presented, using 'Product Frameworker', and 'Product Database' which also supports multiple-viewpoints. 'Product Data Model' is designed, and main data workflows are represented using 'Activity Diagram', one of UML diagrams. These can be used for writing programming codes and developing prototype in order to automatically create activity items in actual schedule management system. Through validation processes, 'Product Model Centered Integration Methodology' is suggested as the new approach for integration of design and construction information.

  • PDF

Development of Calcification-resistant Bovine Pericardium with PEO-$SO_3(II)$ -An implantation study of bovine pericardium at artery and peritoneum- (PEO-$SO_3$를 이용한 항석회화 조직첨포의 개발(II) -동맥과 복막 이식 실험연구-)

  • 김형묵;백만종;김광택;이인성;김학제;이원규;박기동
    • Journal of Chest Surgery
    • /
    • v.31 no.11
    • /
    • pp.1023-1030
    • /
    • 1998
  • Background: Calcific degeneration limits durabilities of the bioprosthetic tissues implanted in the human body. The direct coupling sulphonated polyethyleneoxide(PEO-SO3) to the bioprosthetic tissues after glutaraldehyde(GA) fixation and the removal of residual aldehyde groups from the tissues can augment the effect of calcification-resistance. Materials and methods: To study the anti-calcification effect by PEO-SO3 modification and the removal of the residual aldehyde groups of tissues, surface modified bovine pericardia(BP-PEO-SO3) were preserved in aseptic saline to wash out GA(saline group) and 0.65% GA solution(GA group). And then above two groups and PERIGUARD (Bio-vascular. Co.) (product group) were evaluated with respects to calcium contents and microscopic findings using in vivo implantation models at carotid and femoral artery and peritoneum of 8 adult dogs. Results: In the tissues retrieved from carotid artery, calcium content was significantly decreased in saline group than in other two groups(saline; 2.89±0.31 vs. GA; 6.14±1.08 vs. product; 22.82±5.00 mg/g of dried tissue; p<0.05). In the tissues retrieved from femoral artery and peritoneum, calcium amount was also decreased in saline group than in other two groups, but not reached the significant difference between groups. On the other hand, the pathologic findings of pericardial tissues showed marked destructuction in GA group compared to the other two groups. Conclusions: In this study, covalently PEO-SO3 bound to bovine pericardium decreased calcifications and the anti-calcification effect of BP-PEO-SO3 could be augmented by the washing out the residual aldehyde groups using saline after GA fixation. Conclusively, the PEO-SO3 modified bovine pericardium is highly resistant to calcification and can be useful for the development of calcification-resistant cardiovascular patches and valves.

  • PDF

Target Word Selection Disambiguation using Untagged Text Data in English-Korean Machine Translation (영한 기계 번역에서 미가공 텍스트 데이터를 이용한 대역어 선택 중의성 해소)

  • Kim Yu-Seop;Chang Jeong-Ho
    • The KIPS Transactions:PartB
    • /
    • v.11B no.6
    • /
    • pp.749-758
    • /
    • 2004
  • In this paper, we propose a new method utilizing only raw corpus without additional human effort for disambiguation of target word selection in English-Korean machine translation. We use two data-driven techniques; one is the Latent Semantic Analysis(LSA) and the other the Probabilistic Latent Semantic Analysis(PLSA). These two techniques can represent complex semantic structures in given contexts like text passages. We construct linguistic semantic knowledge by using the two techniques and use the knowledge for target word selection in English-Korean machine translation. For target word selection, we utilize a grammatical relationship stored in a dictionary. We use k- nearest neighbor learning algorithm for the resolution of data sparseness Problem in target word selection and estimate the distance between instances based on these models. In experiments, we use TREC data of AP news for construction of latent semantic space and Wail Street Journal corpus for evaluation of target word selection. Through the Latent Semantic Analysis methods, the accuracy of target word selection has improved over 10% and PLSA has showed better accuracy than LSA method. finally we have showed the relatedness between the accuracy and two important factors ; one is dimensionality of latent space and k value of k-NT learning by using correlation calculation.

Empirical Analysis of Consumer Behavior on the Internet Shopping Mall Choice from the Schema Perspective: Comparison Between Bricks & Clicks and Pure-Player Shopping Mall (스키마 관점에서 살펴본 인터넷 쇼핑몰 선택에 대한 소비자행동의 이해: Bricks & Clicks와 Pure-Player 인터넷 쇼핑몰 비교를 중심으로)

  • Chung, Nam-Ho;Lee, Kun-Chang
    • Asia pacific journal of information systems
    • /
    • v.17 no.4
    • /
    • pp.165-186
    • /
    • 2007
  • With the advent of a wide variety of Internet shopping malls, consumers can choose a best appealing shopping mall from among the Bricks-and-Clicks and Pure-Player malls. Pure-Players launched their operation grandiosely with the early stage of Internet use in 1995. However, after the burst of Dot-com company bubbles in 1997, Pure-Players introduce various types of business models to meet potential needs of consumers. While Pure-Players suffer skeptical views from market analysts as well as consumers, traditional offline companies learned important lessons from Dot-com companies collapse phenomena, and expanded their business channels into online in the name of Bricks-and-Clicks. Nowadays, Bricks-and-Clicks successfully establish in the market as one of reliable business partners among consumers. Therefore, it is no surprise that recent competitions between Bricks-and Clicks and Pure-Players become fiercer than ever to attract potential customers to their websites. In this situation, consumers can choose a shopping mall to their best satisfaction. Consumers can enjoy both offline and online options for shopping because Bricks-and Clicks provide both offline and online channels to consumers, which is compared with Pure-Players offering only online channel. Offline channel is unique in providing consumers with chances to touch and feel target products and services. Meanwhile, online channel is considered very viable and convenient shopping options for consumers. In this respect, it is easily assumed that consumers will show different online shopping behavior when they have to choose either Bricks-and-Clicks mall or Pure-Player mall for the sake of shopping. Remaining research issue in this case is how much consumers' schema would influence online shopping behavior between Bricks-and-Clicks and Pure-Players. Basically, schema is a framework for synthetic information recognition that individual consumers have and is very characteristic in that it focuses not on fragmentary facts but on the combination of various causes affecting results. Consumers' schema is closely represented by trust, structural assurance, and perceived relative advantage towards a specific type of shopping mall. In literature, there exist a lot of studies comparing Bricks-and-Clicks and Pure-Players. However, there is no study to pursue the analysis of consumer behaviors comparing Bricks-and Clicks and Pure-Players from the schema perspective. Therefore, this study aims to investigate this research gap. Empirical analysis is adopted by garnering valid questionnaires from 514 Internet shopping mall users. 237 were mainly using Bricks-and-Clicks for shopping, while 277 were found to visit Pure-Players for shopping. PLS was applied to analyze the survey data to verify the proposed research hypotheses. Findings from the empirical test results are as follows. First, consumers perceive more trust and relative advantage in Pure-Players, comparing with Bricks-and-Clicks. This result is against widely-accepted perception that Bricks-and-Clicks would be perceived by consumers as more trustworthy and relatively advantageous because they have offline reputation and stores. Therefore, it becomes more obvious that Internet is becoming daily necessaries, and consumers increasingly feel very comfortable in using the Internet for their own personal purposes. Second, consumers have firm faith in transaction safety, regardless Bricks-and-Clicks and Pure-Players. This seems due to the fact that most of shopping malls showing dubious transaction safety have no place in the market. In a nutshell, empirical results tell us that Pure-Players will grow very much in the future, to the extent that consumers perceive no difference in comparison with Bricks-and-Clicks. Besides, consumers' schema accumulated through trust and perceived relative advantage plays crucial role in determining consumer behavior.

A Survey of the Current Information Activities in the Advanced Developing Countries (중진국의 정보유통체제 연구)

  • Choi Sung-jin
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.7
    • /
    • pp.89-195
    • /
    • 1980
  • The advanced developing countries including Korea are assumed to have reached a developmental stage which necessitates them to formulate and implement a plan for a national information network. Most of the governments in the advanced developing countries are well aware of the necessity for such a plan and some of them have actually commenced their studies on the feasibility of a national network of their own hoping to achieve maximum utility of their limited information resources. Two urgent problems facing planners in the design of a national information network are identified. One is lack of an optimum organisational model to enable them to meet their own situations, and the other is lack of a guideline to help designers evaluate the alternative structures and models when they are available. In resolving these two problems, network planners in the advanced developing countries would benefit from the achievement of the objectives of the present study. The major objective is to elicit and describe common information needs, desires and value of the people using information, and other common factors which are responsible for the present information services in the advanced developing countries and which have implications for the basic structure of the national information network. The value of this study is to aid administrators in Korea and those in the other advanced developing countries who are responsible for making national policies and who are now beginning to recognise the need for information services with the planning of economic and social development so as to enable all the groups in the community to have access to the information which are essential for decision making, research work, studies and even for recreational reading. This recognition will hopefully give them a rational basis for formulating right policies on information services. The methodology utlised for collecting the required data in this study falls under the category of observation and largely consists of the two techniques: literature review and postal questionnaire. Background information on the individual advanced developing: countries was gathered from monographic and periodical literature. and country reports presented at the various international conferences were analysed for other relevant data. For most of the data needed for the present study, a questionnaire on 'Library and Information Services as They Are Available in the Selected Countries' was formulated. This questionnaire was designed to be completed without help, by an expert who was well informed of the library and information services in his or her country. The questionnaire was intended to look in details at what information services in the advanced developing countries were doing-whom they were serving, in what way, and how well and establish to what extent they were meeting the nation's information requirements. It was also intended to ascertain the respondents' ideas on possible future developments in information provision in their countries, that is, in the advanced devanced developing countries. The questionnaire was posted to a total of 63 natinal librarians, directors of national information centres and those of other major libraries or information centres in 21 selected countries. Complete usable responses were received from 34 persons in 14 countries. In order to identify common characteristics of the information needs and desires in the advanced developing countries and the present situation of the information services to meet them, and the requirements and constraints peculiar to those countries which bought to be considered in the design of a national information network for advanced developing countries, an individual report on the current status of information activities for each of the fourteen countries chosen for this study, was presented. The procedure used was to arrange the data acquired in the questionnaire responses and other sources, in the form of fifteen country reports to be summarised by cross-section characteristics later.

  • PDF

The Effect of Information Protection Control Activities on Organizational Effectiveness : Mediating Effects of Information Application (정보보호 통제활동이 조직유효성에 미치는 영향 : 정보활용의 조절효과를 중심으로)

  • Jeong, Gu-Heon;Jeong, Seung-Ryul
    • Journal of Intelligence and Information Systems
    • /
    • v.17 no.1
    • /
    • pp.71-90
    • /
    • 2011
  • This study was designed to empirically analyze the effect of control activities(physical, managerial and technical securities) of information protection on organizational effectiveness and the mediating effects of information application. The result was summarized as follows. First, the effect of control activities(physical, technical and managerial securities) of information protection on organizational effectiveness showed that the physical, technical and managerial security factors have a significant positive effect on the organizational effectiveness(p < .01). Second, the effect of control activities(physical, technical and managerial securities) of information protection on information application showed that the technical and managerial security factors have a significant positive effect on the information application(p < .01). Third, the explanatory power of models, which additionally put the information protection control activities(physical, technical and managerial securities) and the interaction variables of information application to verify how the information protection control activities( physical, technical and managerial security controls) affecting the organizational effectiveness are mediated by the information application, was 50.6%~4.1% additional increase. And the interaction factor(${\beta}$ = .148, p < .01) of physical security and information application, and interaction factor(${\beta}$ = .196, p < .01) of physical security and information application among additionally-put interaction variables, were statistically significant(p < .01), indicating the information application has mediated the relationship between physical security and managerial security factors of control activities, and organizational effectiveness. As for results stated above, it was proven that physical, technical and managerial factors as internal control activities for information protection are main mechanisms affecting the organizational effectiveness very significantly by information application. In information protection control activities, the more all physical, technical and managerial security factors were efficiently well performed, the higher information application, and the more information application was efficiently controlled and mediated, which it was proven that all these three factors are variables for useful information application. It suggested that they have acted as promotion mechanisms showing a very significant result on the internal customer satisfaction of employees, the efficiency of information management and the reduction of risk in the organizational effectiveness for information protection by the mediating or difficulty of proved information application.

LIM Implementation Method for Planning Biotope Area Ratio in Apartment Complex - Focused on Terrain and Pavement Modeling - (공동주택단지의 생태면적률 계획을 위한 LIM 활용방법 - 지형 및 포장재 모델링을 중심으로 -)

  • Kim, Bok-Young;Son, Yong-Hoon;Lee, Soon-Ji
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.46 no.3
    • /
    • pp.14-26
    • /
    • 2018
  • The Biotope Area Ratio (BAR) is a quantitative pre-planning index for sustainable development and an integrated indicator for the balanced development of buildings and outdoor spaces. However, it has been pointed out that there are problems in operations management: errors in area calculation, insufficiency in the underground soil condition and depth, reduction in biotope area after construction, and functional failure as a pre-planning index. To address these problems, this study proposes implementing LIM. Since the weights of the BAR are mainly decided by the underground soil condition and depth with land cover types, the study focused on the terrain and pavements. The model should conform to BIM guidelines and standards provided by government agencies and professional organizations. Thus, the scope and Level Of Detail (LOD) of the model were defined, and the method to build a model with BIM software was developed. An apartment complex on sloping ground was selected as a case study, a 3D terrain modeled, paving libraries created with property information on the BAR, and a LIM model completed for the site. Then the BAR was calculated and construction documents were created with the BAR table and pavement details. As results of the study, it was found that the application of the criteria on the BAR and calculation became accurate, and the efficiency of design tasks was improved by LIM. It also enabled the performance of evidence-based design on the terrain and underground structures. To adopt LIM, it is necessary to create and distribute LIM library manuals or templates, and build library content that comply with KBIMS standards. The government policy must also have practitioners submit BIM models in the certification system. Since it is expected that the criteria on planting types in the BAR will be expanded, further research is needed to build and utilize the information model for planting materials.

Neuroprotective effects of resveratrol via anti-apoptosis on hypoxic-ischemic brain injury in neonatal rats (신생 백서의 저 산소 허혈 뇌손상에서 항세포사멸사를 통한 resveratrol의 신경보호 효과)

  • Shin, Jin Young;Seo, Min Ae;Choi, Eun Jin;Kim, Jin Kyung;Seo, Eok Su;Lee, Jun Hwa;Chung, Hai Lee;Kim, Woo Taek
    • Clinical and Experimental Pediatrics
    • /
    • v.51 no.10
    • /
    • pp.1102-1111
    • /
    • 2008
  • Purpose : Resveratrol, extracted from red wine and grapes, has an anti-cancer effect, an antiinflammatory effect, and an antioxidative effect mainly in heart disease and also has neuroprotective effects in the adult animal model. No studies for neuroprotective effects during the neonatal periods have been reported. Therefore, we studied the neuroprotective effect of resveratrol on hypoxic-ischemic brain damage in neonatal rats via anti-apoptosis. Methods : Embryonic cortical neuronal cell culture of rat brain was performed using pregnant Sprague-Dawley (SD) rats at 18 days of gestation (E18) for the in vitro approach. We injured the cells with hypoxia and administered resveratrol (1, 10, and $30{\mu}g/mL$) to the cells at 30 minutes before hypoxic insults. In addition, unilateral carotid artery ligation with hypoxia was induced in 7-day-old neonatal rats for the in vivo approach. We injected resveratrol (30 mg/kg) intraperitoneally into animal models. Real-time PCR and Western blotting were performed to identify the neuroprotective effects of resveratrol through anti-apoptosis. Results : In the in vitro approach of hypoxia, the expression of Bax, caspase-3, and the ratio of Bax/Bcl-2, indicators of the level of apoptosis, were significantly increased in the hypoxia group compared to the normoxia group. In the case of the resveratrol-treated group, expression was significantly decreased compared to the hypoxia group. And the results in the in vivo approach were the same as in the in vitro approach. Conclusion : The present study demonstrates that resveratrol plays neuroprotective role in hypoxic-ischemic brain damage during neonatal periods through the mechanism of anti-apoptosis.

Hydro-Mechanical Modelling of Fault Slip Induced by Water Injection: DECOVALEX-2019 TASK B (Step 1) (유체 주입에 의한 단층의 수리역학적 거동 해석: 국제공동연구 DECOVALEX-2019 Task B 연구 현황(Step 1))

  • Park, Jung-Wook;Park, Eui-Seob;Kim, Taehyun;Lee, Changsoo;Lee, Jaewon
    • Tunnel and Underground Space
    • /
    • v.28 no.5
    • /
    • pp.400-425
    • /
    • 2018
  • This study presents the research results and current status of the DECOVALEX-2019 project Task B. Task B named 'Fault slip modelling' is aiming at developing a numerical method to simulate the coupled hydro-mechanical behavior of fault, including slip or reactivation, induced by water injection. The first research step of Task B is a benchmark simulation which is designed for the modelling teams to familiarize themselves with the problem and to set up their own codes to reproduce the hydro-mechanical coupling between the fault hydraulic transmissivity and the mechanically-induced displacement. We reproduced the coupled hydro-mechanical process of fault slip using TOUGH-FLAC simulator. The fluid flow along a fault was modelled with solid elements and governed by Darcy's law with the cubic law in TOUGH2, whereas the mechanical behavior of a single fault was represented by creating interface elements between two separating rock blocks in FLAC3D. A methodology to formulate the hydro-mechanical coupling relations of two different hydraulic aperture models and link the solid element of TOUGH2 and the interface element of FLAC3D was suggested. In addition, we developed a coupling module to update the changes in geometric features (mesh) and hydrological properties of fault caused by water injection at every calculation step for TOUGH-FLAC simulator. Then, the transient responses of the fault, including elastic deformation, reactivation, progressive evolutions of pathway, pressure distribution and water injection rate, to stepwise pressurization were examined during the simulations. The results of the simulations suggest that the developed model can provide a reasonable prediction of the hydro-mechanical behavior related to fault reactivation. The numerical model will be enhanced by continuing collaboration and interaction with other research teams of DECOLVAEX-2019 Task B and validated using the field data from fault activation experiments in a further study.