• 제목/요약/키워드: Prospective approach

검색결과 172건 처리시간 0.026초

Statistical Prediction of Wake Fields on Propeller Plane by Neural Network using Back-Propagation

  • Hwangbo, Seungmyun;Shin, Hyunjoon
    • Journal of Ship and Ocean Technology
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    • 제4권3호
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    • pp.1-12
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    • 2000
  • A number of numerical methods like Computational Fluid Dynamics(CFD) have been developed to predict the flow fields of a vessel but the present study is developed to infer the wake fields on propeller plane by Statistical Fluid Dynamics(SFD) approach which is emerging as a new technique over a wide range of industrial fields nowadays. Neural network is well known as one prospective representative of the SFD tool and is widely applied even in the engineering fields. Further to its stable and effective system structure, generalization of input training patterns into different classification or categorization in training can offer more systematic treatments of input part and more reliable result. Because neural network has an ability to learn the knowledge through the external information, it is not necessary to use logical programming and it can flexibly handle the incomplete information which is not easy to make a definition clear. Three dimensional stern hull forms and nominal wake values from a model test are structured as processing elements of input and output layer respectively and a neural network is trained by the back-propagation method. The inferred results show similar figures to the experimental wake distribution.

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System Representation for the Control System of the Follow-up Mechanism on the Marine Gyro Compass

  • Sang-Jib Lee
    • 한국항해학회지
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    • 제4권1호
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    • pp.31-50
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    • 1980
  • It does not seem necessarily practicable to keep the system always in optimal condition, athough the control system of the follow-up mechanism on the most marine gyro compasses is to be adjusted by the operator through the gain adjustment. Sometimes a sustained oscillation or an incorrect gyro reading occurs to the system. For such a system any systematical research or theoretical basis of the guide for the optimal gain adjustment has not been reported yet. As a basic investigation of the theoretical system analysis to solve the problems concerned, the author attempts in this paper to express the system in a mathematical model deduced from the results of the theoretical approach and the experimental observation of each element contained in the follow-up mechanism of Hokshin D-1 gyro compass, and to constitute an over-all closed loop transfer function. This funciton being reverted to a fourth orderlinear differential equation, the first order simultaneous differential equations are obtained by means of the state-variables. The latter equations are solved by the Runge-Kutta method with digital computer. By comparing the characteristic of the simulated over-all output with that of the experimental result, it is shown that both outputs are nearly consistent with each other. It is also expected that the system representation proposed by this paper is valid and will be a prospective means in a further study on the design and optimal adjustment of the system.

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대혈관전위증의 Senning 수술요법 (The Senning Operation for Transition of the Great Arteries -a 7-year prospective study -)

  • 김기봉;노준량
    • Journal of Chest Surgery
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    • 제22권5호
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    • pp.753-759
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    • 1989
  • Recently, the arterial switch operation has received more interest and increased application for many patients with TGA [Transposition of the Great Arteries]. Not all patients, however, are suitable candidates for this approach, and its success will be measured against the Senning procedure. From June 1982 through June 1989, 48 consecutive patients underwent correction of TGA by a modification of the Senning procedure in our hospital. 34 were males and 14 females, with ages ranging from 3 months to 99 months [mean age 14 months]. The patients were divided into two groups, group I [TGA with intact ventricular septum or without significant pulmonary hypertension] and group II [TGA with significant pulmonary hypertension]. The hospital mortality was 9.5 % in group I and 55.6 % in group lI. 31 patients were discharged from the hospital after a Senning operation and have been followed a mean of 31.2 months. There were 5 late deaths, 3 in group I and 2 in group II. All patients were followed up with EKG, echocardiogram, and in several cases, Holter monitor and cardiac catheterization and angiography were also performed. There have been arrhythmias in 7, superior vena caval obstruction in 5, pulmonary venous obstruction in 2 and tricuspid insufficiency and/or right ventricular dysfunction in 16 patients. The Senning operation for Simple TGA can be performed with a low operative mortality and morbidity, but tricuspid insufficiency and/or depressed right ventricular function can be a problem with prolonged follow up.

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Genetic Polymorphism of Interleukin 10 Gene and Sasang Constitution in Bell's Palsy Patients

  • Kim, Jong-Won;Seo, Jung-Chul;Jung, Tae-Young
    • 동의생리병리학회지
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    • 제19권2호
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    • pp.515-519
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    • 2005
  • We hypothesized that the IL10 gene is important candidate in the development of Bell's palsy and specific genotypic and allelic variations should be associated with Bell's palsy in the Korean population. In this study, we assessed the SNP (single-nucleotide polymorphism) of IL10 in patients with Bell's palsy. 62 patients with Bell's palsy were selected from the subjects who visited for the Bell's palsy service of the department of acupuncture & moxibustion, college of Oriental Medicine, Daegu Haany University from May 2002 to May 2003. Pyrosequencing was performed for genetic analyses. There was no statistically significant genotypic distribution difference between control and Bell's palsy group And there was not statistically significant allelic frequency difference between control and Bell's palsy group. In this study the IL10 genotypemight not be the risk factor of Bell's palsy patients in Korean. studies will be necessary for the exact genetic markers. Establishment of more systemic approach and high quality of prospective cohorts will be necessary for the good prediction of genetic markers.

e-Healthcare 환경 내 개인정보 보호 모델 (Privacy Information Protection Model in e-Healthcare Environment)

  • 김경진;홍승필
    • 인터넷정보학회논문지
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    • 제10권2호
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    • pp.29-40
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    • 2009
  • 인터넷 등의 정보기술의 발전은 기존의 의료기술에 빠른 변화를 가져오면서 e-Healthcare가 사회적 이슈로 등장하고 있다. 의료정보화 패러다임의 새로운 전환점이라 할 수 있는 e-Healthcare는 국내에서 의료정책방안이나 기술개발을 하고 있지만, 아직 의료정보화의 기반이 되는 인프라는 부족한 수준이며 개방된 인터넷 환경 내 역공학적 측면으로 민감한 의료정보 유출 및 프라이버시 침해에 대한 문제가 대두되는 실정이다. 본 논문에서는 앞서 제시한 문제점의 해결방안으로 e-Healthcare환경 내 개인의 의료정보 보호를 위한 역할기반의 접근제어 시스템(HPIP - Health Privacy Information Protection)을 네 가지 주요 메커니즘(사용자 신분확인, 병원 권한확인, 진료기록 접근제어, 환자진단)으로 제안하였으며, 실 환경에서 효과적으로 활용될 수 있도록 프로토타이핑을 통해 그 가능성을 타진해 보았다.

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The Six Dimensions of Resident Satisfaction and Their Impact on Word-of-Mouth (WOM) Intention in a Continuing Care Retirement Community (CCRC): A Case Study

  • Lee, Ji-Eun
    • 아태비즈니스연구
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    • 제11권4호
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    • pp.49-63
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    • 2020
  • Purpose - This study aims to assess six aspects of resident satisfaction (satisfaction with room, home, social interaction, meals service, staff care, and resident involvement) and to identify the most influential aspect of satisfaction upon word-of-mouth (WOM) intention in a continuing care retirement community (CCRC). Design/methodology/approach - A total of 293 paper survey questionnaires with a cover letter and postage paid envelopes were mailed to the CCRC residents. To test reliability and validity of the multidimensional resident satisfaction, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used. Then, the structural equation modeling technique (SEM) was applied to test causal relationship between resident satisfaction and WOM intention. Multiple regression was used to identify the most influential aspect of resident satisfaction on WOM intention in the CCRC. Findings - The results of EFA and CFA on the 157 responses received out of the total 293 surveys indicated that six dimensions of resident satisfaction were statistically distinct. Among the six dimensions, satisfaction with resident involvement, social interaction, and staff care significantly influenced their WOM intention. Furthermore, the most influential aspect of satisfaction upon WOM intention was resident involvement. Research implications or Originality - This study empirically tested the six dimensions of CCRC resident satisfaction, and identified resident involvement as the most influential factor upon WOM intention in a CCRC where WOM intentions plays a crucial role during the selection process of prospective residents.

Implications of 3-Dimensional Printed Spinal Implants on the Outcomes in Spine Surgery

  • Fiani, Brian;Newhouse, Alexander;Cathel, Alessandra;Sarhadi, Kasra;Soula, Marisol
    • Journal of Korean Neurosurgical Society
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    • 제64권4호
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    • pp.495-504
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    • 2021
  • Three-dimensional printing (3DP) applications possess substantial versatility within surgical applications, such as complex reconstructive surgeries and for the use of surgical resection guides. The capability of constructing an implant from a series of radiographic images to provide personalized anatomical fit is what makes 3D printed implants most appealing to surgeons. Our objective is to describe the process of integration of 3DP implants into the operating room for spinal surgery, summarize the outcomes of using 3DP implants in spinal surgery, and discuss the limitations and safety concerns during pre-operative consideration. 3DP allows for customized, light weight, and geometrically complex functional implants in spinal surgery in cases of decompression, tumor, and fusion. However, there are limitations such as the cost of the technology which is prohibitive to many hospitals. The novelty of this approach implies that the quantity of longitudinal studies is limited and our understanding of how the human body responds long term to these implants is still unclear. Although it has given surgeons the ability to improve outcomes, surgical strategies, and patient recovery, there is a need for prospective studies to follow the safety and efficacy of the usage of 3D printed implants in spine surgery.

Scoping Review of Machine Learning and Deep Learning Algorithm Applications in Veterinary Clinics: Situation Analysis and Suggestions for Further Studies

  • Kyung-Duk Min
    • 한국임상수의학회지
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    • 제40권4호
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    • pp.243-259
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    • 2023
  • Machine learning and deep learning (ML/DL) algorithms have been successfully applied in medical practice. However, their application in veterinary medicine is relatively limited, possibly due to a lack in the quantity and quality of relevant research. Because the potential demands for ML/DL applications in veterinary clinics are significant, it is important to note the current gaps in the literature and explore the possible directions for advancement in this field. Thus, a scoping review was conducted as a situation analysis. We developed a search strategy following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed and Embase databases were used in the initial search. The identified items were screened based on predefined inclusion and exclusion criteria. Information regarding model development, quality of validation, and model performance was extracted from the included studies. The current review found 55 studies that passed the criteria. In terms of target animals, the number of studies on industrial animals was similar to that on companion animals. Quantitative scarcity of prediction studies (n = 11, including duplications) was revealed in both industrial and non-industrial animal studies compared to diagnostic studies (n = 45, including duplications). Qualitative limitations were also identified, especially regarding validation methodologies. Considering these gaps in the literature, future studies examining the prediction and validation processes, which employ a prospective and multi-center approach, are highly recommended. Veterinary practitioners should acknowledge the current limitations in this field and adopt a receptive and critical attitude towards these new technologies to avoid their abuse.

Transition Substitution of Desired Bases in Human Pluripotent Stem Cells with Base Editors: A Step-by-Step Guide

  • Ju-Chan Park;Keun-Tae Kim;Hyeon-Ki Jang;Hyuk-Jin Cha
    • International Journal of Stem Cells
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    • 제16권2호
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    • pp.234-243
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    • 2023
  • The recent advances in human pluripotent stem cells (hPSCs) enable to precisely edit the desired bases in hPSCs to be used for the establishment of isogenic disease models and autologous ex vivo cell therapy. The knock-in approach based on the homologous directed repair with Cas9 endonuclease, causing DNA double-strand breaks (DSBs), produces not only insertion and deletion (indel) mutations but also deleterious large deletions. On the contrary, due to the lack of Cas9 endonuclease activity, base editors (BEs) such as adenine base editor (ABE) and cytosine base editor (CBE) allow precise base substitution by conjugated deaminase activity, free from DSB formation. Despite the limitation of BEs in transition substitution, precise base editing by BEs with no massive off-targets is suggested to be a prospective alternative in hPSCs for clinical applications. Considering the unique cellular characteristics of hPSCs, a few points should be considered. Herein, we describe an updated and optimized protocol for base editing in hPSCs. We also describe an improved methodology for CBE-based C to T substitutions, which are generally lower than A to G substitutions in hPSCs.

Antibiotic resistance in livestock, environment and humans: One Health perspective

  • Sriniwas Pandey;Hyunok Doo;Gi Beom Keum;Eun Sol Kim;Jinok Kwak;Sumin Ryu;Yejin Choi;Juyoun Kang;Sheena Kim;Na Rae Lee;Kwang Kyo Oh;Ju-Hoon Lee;Hyeun Bum Kim
    • Journal of Animal Science and Technology
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    • 제66권2호
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    • pp.266-278
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    • 2024
  • Antibiotic resistance (AR) is a complex, multifaceted global health issue that poses a serious threat to livestock, humans, and the surrounding environment. It entails several elements and numerous potential transmission routes and vehicles that contribute to its development and spread, making it a challenging issue to address. AR is regarded as an One Health issue, as it has been found that livestock, human, and environmental components, all three domains are interconnected, opening up channels for transmission of antibiotic resistant bacteria (ARB). AR has turned out to be a critical problem mainly because of the overuse and misuse of antibiotics, with the anticipation of 10 million annual AR-associated deaths by 2050. The fact that infectious diseases induced by ARB are no longer treatable with antibiotics foreshadows an uncertain future in the context of health care. Hence, the One Health approach should be emphasized to reduce the impact of AR on livestock, humans, and the environment, ensuring the longevity of the efficacy of both current and prospective antibiotics.