• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.16-21
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• 2008

Aero-engine, as one kind of rotating machinery with complex structure and high rotating speed, has complicated vibration faults. Therefore, condition monitoring and fault diagnosis system is very important for airplane security. In this paper, a vibration data acquisition and intelligent fault diagnosis system is introduced. First, the vibration data acquisition part is described in detail. This part consists of hardware acquisition modules and software analysis modules which can realize real-time data acquisition and analysis, off-line data analysis, trend analysis, fault simulation and graphical result display. The acquisition vibration data are prepared for the following intelligent fault diagnosis. Secondly, two advanced artificial intelligent(AI) methods, mapping-based and rule-based, are discussed. One is artificial neural network(ANN) which is an ideal tool for aero-engine fault diagnosis and has strong ability to learn complex nonlinear functions. The other is data mining, another AI method, has advantages of discovering knowledge from massive data and automatically extracting diagnostic rules. Thirdly, lots of historical data are used for training the ANN and extracting rules by data mining. Then, real-time data are input into the trained ANN for mapping-based fault diagnosis. At the same time, extracted rules are revised by expert experience and used for rule-based fault diagnosis. From the results of the experiments, the conclusion is obvious that both the two AI methods are effective on aero-engine vibration fault diagnosis, while each of them has its individual quality. The whole system can be developed in local vibration monitoring and real-time fault diagnosis for aero-engine.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.6
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• pp.1044-1055
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• 2015

DPCap analysis can assist in determining the maximum environmental forces the DP system can counteract for a given heading. DPCap analysis results are highly affected by the thrust forces provided by the thrust system which consists of several kinds of thrusters. The thrust forces and moment are determined by the maximum thrust of the thrusters as well as the thruster configuration. In this paper, a novel local optimization of thruster configuration based on a synthesized positioning capability criterion is proposed. The combination of the discrete locations of the thrusters forms the thruster configuration and is the input, and the synthesized positioning capability is the output. The quantified synthesized positioning capability of the corresponding thruster configuration can be generated as the output. The optimal thruster configuration is the one which makes the vessel has the best positioning capability. A software program was developed based on the present study. A local optimization of thruster configuration for a supply vessel was performed to demonstrate the effectiveness and efficiency of the program. Even though the program cannot find the global optimal thruster configuration, its high efficiency makes it essentially practical in an engineering point. It may be used as a marine research tool and give guidance to the designer of the thrust system.

• Journal of the Korea Society of Computer and Information
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• v.20 no.1
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• pp.49-62
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• 2015

In this study we have proposed the prototype of design support device for architectural design assessment using the building information modeling(BIM) data and the augmented reality(AR) technology. The proposed system consists of novel hardware composition with the transparent display, the mock-up model and the digital architectural model in the new shape of frame. The removal of background and the correction of viewer point in the capture video are proposed in order to use the transparent display in AR application. The BIM data formats are reviewed to be converted for using in AR application. Also the proposed system can be expanded to multi-user collaboration system from two user system through the suggested hardware and software compositions. The results of this study will be applied to use the mock-up model and digital architectural model in order to carry out the design assessment process efficiently and economically in the architectural design field.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.377-382
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• 2021

A fuzzy relation between X and Y as fuzzy subset of X × Y was proposed by Zadeh. Subsequently, several researchers have applied the notion of fuzzy subsets to various branches of mathematics and computer sciences. Murali an Nemitz have studied fuzzy relations connected with fuzzy equivalence relations and fuzzy functions. Ounalli and Jaoua defined a fuzzy difunctional relation on a set. difunctional relations are versatile mathematical tool, which can be used in software design and in database theory. Their work have revealed the usefulness of difunctional relations in program specification and in defining program correctness. The main goal of this paper is to define a fuzzy deterministic relation on a set, characterize the fuzzy deterministic relation as its level subsets and investigate some properties in connection with fuzzy deterministic relation. In particular we prove that a fuzzy relation R is fuzzy deterministic iff R is a fuzzy function.

• Journal of Pharmacopuncture
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• v.24 no.3
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• pp.107-121
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• 2021

Objectives: The purpose of this study is to analyze the efficacy of traditional Chinese medicine (TCM) injections specified in the clinical guideline for COVID-19 by conducting a meta-analysis of viral pneumonia data. Methods: TCM injections data on viral pneumonia were collected until July 31, 2021. CNKI, PubMed, EMBASE, and the Cochrane electronic database were used to collect the clinical data. "COVID-19," "Viral pneumonia," "Tanreqing," "Xiyanping," "Reduning," "Xingnaojing," "Xuebijing," "Shenmai," "Shengmai," and "Shenfu" were used as keywords. All data collected were mainly about TCM injections and viral pneumonia. Furthermore, studies that included results such as the total effective rate, cough disappearance time, antipyretic time, lung rhomboid disappearance time, and adverse drug reaction were collected for the meta-analysis to identify the efficacy of TCM injections. However, data unrelated to TCM injections specified in the clinical guidelines for COVID-19 or viral pneumonia were excluded. The quality of included RCTs was assessed by the Cochrane Risk of Bias Tool, and Review Manager 5.3 software was used to conduct the meta-analysis. Results: A total of 18 studies with 1540 patients were included in this study. The results of the meta-analysis showed that the total effective rate OR = 4.61 (95% CI 2.92, 7.25, p = 1.00/ I² = 0%); the cough disappearance time: SMD -1.23 (-1.37, -1.09, p < 0.00001/ I² = 94%); the antipyretic time: SMD -1.26 (-1.40, -1.11, p < 0.00001/ I²=94%); lung rhomboid disappearance time: SMD -1.17 (-1.33, -1.02, p < 0.00001/ I² = 89%); and adverse drug reaction was OR 0.36 (95% CI 0.20, 0.64, p = 0.21/ I² = 30%). From the results, the treatment group (TCM injection) showed better efficacy than the control group (Western medication). Conclusion: Xiyanping, Reduning, and Tanreqing injections may yield benefits as COVID-19 treatments. However, clinical trials on TCM injections for the treatment of COVID-19 are still lacking. More high-quality clinical trials are still required.

• Journal of Korean Academy of Nursing
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• v.51 no.5
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• pp.617-629
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• 2021

Purpose: The aim of this study was to examine the validity and reliability of the Korean version of the self-efficacy for managing chronic disease 6-item scale (SECD-6-K). Methods: The English version of the Self-Efficacy for Managing Chronic Disease 6-item Scale first underwent forward and backward translation procedures. The SECD-6-K was then used to collect data from 350 adults diagnosed with chronic diseases. Content, construct, convergent, discriminant, and criterion validity were all evaluated. Reliability was assessed using Cronbach's α. SPSS 25.0 and the data were analyzed using AMOS 26.0 software. Results: The SECD-6-K consists of six items in two domains: disease management and health behavior. The results for construct, convergent, and discriminant validity were good. Exploratory factor analysis produced eigen values between 2.27 and 3.28, with factors total explained cumulative variance of 91.1%. Confirmatory factor analysis supported goodness of fit and reliability for the modified SECD-6-K model. The criterion validity also showed significant correlation with both the Patient Health Questionnaire and 12-item Short-Form Health Survey version 2. Finally, reliability was found to be excellent. Conclusion: This study identified the high reliability and validity of SECD-6-K. The SECD-6-K is an appropriate tool for determining Korean patients' self-efficacy in managing their chronic conditions. Therefore, this scale may be used in clinical settings as well as in educational and research settings.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.24.1-24.7
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• 2020

Background: In daily practice, three-dimensional patient-specific jawbone models (3D models) are a useful tool in surgical planning and simulation, resident training, patient education, and communication between the physicians in charge. The progressive improvements of the hardware and software have made it easy to obtain 3D models. Recently, in the field of oral and maxillofacial surgery, there are many reports on the benefits of 3D models. We introduced a desktop 3D printer in our department, and after a prolonged struggle, we successfully constructed an environment for the "in-house" fabrication of the previously outsourced 3D models that were initially outsourced. Through various efforts, it is now possible to supply inexpensive 3D models stably, and thus ensure safety and precision in surgeries. We report the cases in which inexpensive 3D models were used for orthodontic surgical simulation and discuss the surgical outcomes. Review: We explained the specific CT scanning considerations for 3D printing, 3D printing failures, and how to deal with them. We also used 3D models fabricated in our system to determine the contribution to the surgery. Based on the surgical outcomes of the two operators, we compared the operating time and the amount of bleeding for 25 patients who underwent surgery using a 3D model in preoperative simulations and 20 patients without using a 3D model. There was a statistically significant difference in the operating time between the two groups. Conclusions: In this article, we present, with surgical examples, our in-house practice of 3D simulation at low costs, the reality of 3D model fabrication, problems to be resolved, and some future prospects.

• Therapeutic Science for Rehabilitation
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• v.10 no.2
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• pp.53-74
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• 2021

Objective : The purpose of this study was to examine foreign literature on the evaluation and interventions for motor functions in children. Methods : Studies in this review were identified by searching the PubMed, Cochrane Library (Embase) databases from those published form January 2010 to March 2020 using the following keywords: "motor function test" or "motor function measure" or "movement assessment" or "motor proficiency test" or "motor scale" or "motor skill" and children. Results : Of the total 37 identified studies, 14 analyzed evaluations, 23 analyzed interventions, all of which were randomized control trials. Studies on evaluations were increasingly more common, in contrast to studies on interventions for motor functions. The most frequent field of research was rehabilitation. The studies on evaluations included the AIMS and MABC-II, and GMFM was the most frequently used intervention. Interventions were most commonly used in task-oriented training (six studies). Conclusion : This study aimed to provide a basis for therapists to choose effective motor function evaluation and interventions for clinical trials by analyzing studies related to interventions for and evaluation of motor function in children.

• Journal of Navigation and Port Research
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• v.45 no.2
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• pp.61-68
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• 2021

Logistics movement using ships has been used for many centuries, but maritime accidents are still difficult to predict and they occur on a large scale. The International Maritime Organization (IMO) made it mandatory to install Electronic Chart Display and Information System (ECDIS) for safe seas, but S-57 standards applied to equipment were not updated over 30 years. In addition, it is difficult to keep the equipment up-to-date and revise standards as ships move around the world. In consideration of the limitations of S-57, the IHO developed the new standard as S-100 rather than an update of the S-57. In this study, the previously developed S-100 tool and S/W were configured as one platform and applied to the S-100 ECDIS. The platform conducts as the S-100 cycle and ecosystem from the creation of standards to release and practical use in ships. The hydrographic information standard is machine-readable as defined in S-100, and it has been validated that the latest standard can be applied using the Plug and Play (PnP) function without software system updates. It is expected that international organization such as the International Hydrographic Office (IHO) and the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) shall develop and release standards and mariners can easily apply the latest standards to equipment through the machine-readable platform.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.127-134
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• 2021

This study aims to determine the role of innovative capabilities as a mediator in analyzing entrepreneurial marketing's effect on sustainable competitive advantage in food and beverage micro-, small-, and medium- enterprises (MSMEs). Data was obtained from a food and beverage store manager in Tangerang City, comprising 119 samples. Furthermore, the G⁎Power, a tool used to calculate statistical power analysis for various t-tests, F tests, χ2 tests, z tests, and several exact tests, was used to determine the number of research samples, the α error probability of 5%, and 3 variables. The data collection method used questionnaires with Likert Scale 1-5 to indicate strongly disagree to strongly agree. To analyze data, we used Path Analysis supported by SmartPLS statistics software. Path analysis is a form of multiple regression statistical analysis that is used to evaluate causal models by examining the relationships between a dependent variable and two or more independent variables. It aims to provide estimates of the magnitude and significance of hypothesized causal connections between sets of variables. The data processing process took place in two stages, namely the estimation model testing with validity and reliability, and the structural model testing to decide the impact or correlation between variables utilizing the t-test. The result showed a positive and significant effect of entrepreneurial marketing to innovative capability and competitive advantage through the innovative capability of MSMEs.