• Journal of Power Electronics
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• v.15 no.1
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• pp.146-159
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• 2015

Since the power capacity needed for the propulsion of large ships is very large, a multiphase AC induction propulsion mode is generally adopted to meet the higher requirements of reliability, redundancy and maintainability. This paper gives a detailed description of the development of a 20MW fifteen-phase PWM driver for advanced fifteen-phase propulsion induction motors with a special third-harmonic injection in terms of the main circuit hardware, control system design, experiments, etc. The adoption of the modular design method for the main circuit hardware design can make the enclosed mechanical structure simple and maintainable. It can also avoid the larger switch stresses caused by the multiple turn on of the IGBTs in conventional large-capacity converter systems. The use of the distributed controller design method based on a high-speed fiber-optic ring net for the control system can overcome such disadvantages as the poor reliability and long maintenance times arising from the conventional centralized controller which is designed according to point-to-point communication. Finally, the performance of the 20MW PWM driver is verified by experimentation on a new fifteen-phase induction propulsion motor.

• Journal of Biosystems Engineering
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• v.35 no.6
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• pp.401-407
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• 2010

In this study, computer simulations were conducted to assess the use of a circulating concurrent-flow dryer for rapeseed drying and to determined the effect of this drying method on the germination ratio of rapeseed after the drying process was complete. The simultaneous heat and mass transfer between air and rapeseed in a concurrent-flow dryer was examined by simulation. The drying simulation was based on several parameters with sequent time series. Equations concerning air psychrometrics, physical properties, thermal properties, equilibrium moisture content, thin layer drying of rapeseed, etc. were all combined to solve the simulation models. Based on energy and mass transfer in the concurrent-flow drying model, a simulation program for the circulating concurrent-flow rapeseed dryer was built along with a detailed description of the mathematical solution to the model. A pilot scale circulating concurrent-flow dryer(200 kg/batch) was used to verify the fitness of the simulation program. A comparison between the experimental data and the model predicted results was presented and discussed. The drying parameters and germination ratio were analyzed and the accuracy of the simulation program was evaluated. The simulation program proved to be reliable and was shown to be a convenient tool for predicting rapeseed drying and germination ratio of rapeseed in a concurrent-flow dryer.

• Journal of Korean language education
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• v.28 no.4
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• pp.121-147
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• 2017

This study shows the current management status and the results of B University's multicultural creative-HR team's voice training supporters' preparation course that is part of the local funding project at the university. For this, the concept of voice training and educational contents of the multicultural members are first extracted from several documents. Then, a description of the management case of B University's voice training supporters' education course is given regarding the goals, operator of management, propulsion progress, and contents of previous education. For analyzing the management results of this work, in-depth interviews with the supporters and a half-structured survey are conducted with the voice academy main instructors. Moreover, reports of the work results, work journals of supporters and etc. are used for analyzing the results. According to the results of this analysis, the aspect of education, previous education contents, and teaching practicum are not organically connected. A more detailed curriculum about the comprehension ability of practical affairs is needed for managing a classroom. In aspect of management, the preparatory stage of voice training course and the practice stage were not linked, and thus, more cooperation is required with the main instructors. Although the results are limited, the voice training of the supporters' training course has its implications. First, the education of Korean pronunciation and intonation are provided for the supporters, thereby being able to facilitate learner-centered education. Second, it demonstrates in an empirical case that a class can be administered by specializing in Korean pronunciation and intonation. At last, it can provide a chance to practice teaching and offer field experience for students who have a Korean education major.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.5
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• pp.893-900
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• 2019

This paper deals with the analysis of SON (Self Organization Network) technology in LTE networks. SON is a unique LTE feature compared to previous cellular systems UMTS and GSM, and is a cost-effective tool for achieving the best performance in a changing environment. In addition, SON has the function of automating the settings of the network, enabling centralized planning and reducing the need for manual tasks. SON is largely divided into three categories: Self-Configuration, Self-Optimization, and Self-Healing. Each large category has a detailed description, and all the technologies in each category come together to complete the technology called SON. In this paper, we analyzed intensively about ANR among the techniques of Self-Configuration in each of the three categories.

• ALGAE
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• v.36 no.3
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• pp.165-174
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• 2021

Radicilingua Papenfuss and Calonitophyllum Aregood are two small genera of the family Delesseriaceae that consist of only three and one taxonomically accepted species, respectively. The type species of these genera, Radicilingua thysanorhizans from England and Calonitophyllum medium from the Americas, are morphologically very similar, with the only recognized differences being vein size and procarp development. To date, only other two species were recognized inside the genus Radicilingua: R. adriatica and R. reptans. In this study, we analysed specimens of Radicilingua collected in the Adriatic and Ionian Sea (Mediterranean), including a syntype locality of R. adriatica (Trieste, northern Adriatic Sea), alongside material from near the type locality of R. thysanorhizans (Torpoint, Cornwall, UK). The sequences of the rbcL-5P gene fragment here produced represent the first molecular data available for the genus Radicilingua. Phylogenetic reconstruction showed that the specimens from the Adriatic and Ionian Seas were genetically distinct from the Atlantic R. thysanorhizans, even if morphologically overlapping with this species. A detailed morphological description of the Mediterranean specimens, together with an accurate literature search, suggested that they were distinct also from R. adriatica and R. reptans. For these reasons, a new species was here described to encompass the Mediterranean specimens investigated in this study: R. mediterranea Wolf, Sciuto & Sfriso. Moreover, in the rbcL-5P tree, sequences of the genera Radicilingua and Calonitophyllum grouped in a well-supported clade, distinct from the other genera of the subfamily Nitophylloideae, leading us to propose that Calonitophyllum medium should be transferred to Radicilingua.

• Advances in Computational Design
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• v.4 no.2
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• pp.155-177
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• 2019

Operation and Maintenance (O&M) phase is the main contributor to the total lifecycle cost of a building. Previous studies have described that Building Information Models (BIM), if available with detailed asset information and their properties, can enable rapid troubleshooting and execution of O&M tasks by providing the required information of the facility. Despite the potential benefits, there is still rarely BIM with Mechanical, Electrical and Plumbing (MEP) assets and properties that are available for O&M. BIM is usually not in possession for existing buildings and generating BIM manually is a time-consuming process. Hence, there is a need for an automated approach that can reconstruct the MEP systems in BIM. Previous studies investigated automatic reconstruction of BIM using architectural drawings, structural drawings, or the combination with photos. But most of the previous studies are limited to reconstruct the architectural and structural components. Note that mechanical components in the building typically require more frequent maintenance than architectural or structural components. However, the building mechanical drawings are relatively more complex due to various type of symbols that are used to represent the mechanical systems. In order to address this challenge, this paper proposed a symbol recognition framework that can automatically recognize the different type of symbols in the building mechanical drawings. This study applied vector-based computer vision techniques to recognize the symbols and their properties (e.g., location, type, etc.) in two vector-based input documents: 2D drawings and the symbol description document. The framework not only enables recognizing and locating the mechanical component of interest for BIM reconstruction purpose but opens the possibility of merging the updated information into the current BIM in the future reducing the time of repeated manual creation of BIM after every renovation project.

• The Journal of Pediatrics of Korean Medicine
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• v.32 no.4
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• pp.121-140
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• 2018

Objectives This research was aimed to analyze and assess the articles of qualitative research of Pediatrics by following Consolidated Criteria for Reporting Qualitative Research (COREQ). Methods Two researchers analyzed and assessed the reports' quality and appropriateness based on COREQ guideline. The articles that failed to achieve consensus from the two researchers, the third researcher made a final decision. Results A total of fifty-six reports which used caregivers as participants, were selected and adopted qualitative research methods were chosen. In most qualitative studies, COREQ was not implemented. Some parts of the studies were poorly described and elaborated when reviewing them based on the COREQ guidelines. In the 'Research team and reflexivity', there was lack of description about the researcher. In the 'Study design', there were no detailed descriptions on the approaches they took in recruiting their study participants. There was not enough detail reflexivity participants who refused, and where the recruitment took place. There were also no records of whether there was a pilot test or a data saturation. In 'Analysis and findings' section, there were few articles mentioning Participant checking, and the main opinion of the participants were well analyzed in all the papers, but excluding opinions of few participants. Conclusions There are still many qualitative studies that have caregivers as participants, in the field of pediatrics. However, methodological skills are insufficient. The use of the COREQ guidelines should be further implemented for more robust and methodological improvement.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.3
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• pp.1-13
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• 2019

Objectives This review aims to analyze the current research trend in the usage of bee venom (BV) acupuncture for spinal diseases. Methods We collected 80 articles on BV acupuncture clinical study for spinal diseases by searching Korean web databases 'Journal of Korean Medicine Rehabilitation', 'Oriental Medicine Advanced Searching Integrated System', 'Korean Traditional Knowledge Portal' from 1999 to 2018. Results We summarized the most frequent clinical treatment methods of BV acupuncture. 1. Herniated intervertebral disc was treated for 40% and the treated spinal diseases were various. 2. '1:10,000' in the type of BV was chosen for 21%. 3. 29% of studies used 6-7 acupoints per session and 23% of studies used 'BL' as the injection site. 3. The highest volume of injected BV into each acupoint was 0.1 cc for 34% and the highest total volume of injected BV was 1.0 cc for 39%. Conclusions We found the limited evidence on the lack of consensus and detailed description in the reported experimental design. The results in this review suggest that future works should focus on more consistent and systematic study for the reproducible and standardized treatment methods.

• CELLMED
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• v.9 no.3
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• pp.3.1-3.7
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• 2019

Recent researches on adipocytes in human and mice model have reported that the adipocytes are not only the fat depots but having role in maintenance of physiology and metabolism through adipokines released by them in accordance to their anatomical location. Ayurveda scholars too have mentioned different tissues like Vasa (inter muscular fat), Meda (visceral fat) and Majja (bone marrow) which are predominantly rich in adipocytes similar to adipose tissues, with a different sites, functions, compositions and pathological outcomes. The metabolic effect of Meda and Majja Dhatu on other tissues like muscle (Mamsa Dhatu), bone (Asthi Dhatu) and reproductive tissue (Shukra Dhatu) shows their functional interdependence. The detailed description of therapeutic indications of Vasa and Majja under Snehakarma (oleation therapy) illustrates that clinical physiology of these tissues have been elaborated rather than general physiology. This article is an attempt to comprehend the physiological aspect of Vasa, Meda and Majja retrospectively on the basis of their therapeutic indication for the management of variety of disorders, in the form of Sneha through different therapeutic procedures. An effort has been also taken to distinguish Vasa, Meda, Majja based on the functional peculiarities of adipocytes present in different sites of body like omentum, muscle and bone marrow. Critical observation of explanations of Vasa, Meda and Majja in Ayurveda compendia and advanced research in field of adipocytes reflected that Ayurveda scholars had deep insights regarding the various dimensions of adipocytes, most of which are in consistent with the advanced physiology and biomolecular studies of adipocytes.

• International Journal of Advanced Culture Technology
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• v.7 no.1
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• pp.243-247
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• 2019

The most commonly used 3D modeling file formats are OBJ (Wavefront file format specification) and STL (STereoLithography). Although they have a common point of view in 3D on the screen, detailed functions are different according to purpose of development. OBJ is the most commonly used 3D file format and STL is mainly used as 3D file format for 3D printing. However, in the field of Scientific Visualization, precise analysis is required. There is a difference in accuracy depending on the type of 3D file format. OBJ and STL are not suitable for delicate surface description because they form meshes in the form of triangular polygons. And if you increase the number of triangle polygons, it will be smoother, but the file size also increases exponentially and causes excessive CPU usage. In contrast, VTK provides a variety of polygon structures, including triangular polygons as well as rectangular polygons and cube polygons. Thus, delicate surface depiction is possible. Delicate surface rendering is possible and file size is not large. This paper describes the concept and structure of VTK. We also compared the load times and file sizes between VTK, STL, and OBJ in the Chrome browser. In addition, the difference in surface rendering ability between VTK, STL, and OBJ is intuitively viewed based on the screen in which each 3D file format is implemented under the same conditions. This study is expected to be helpful for efficient 3D file format for precise implementation of Web - based Scientific Visualization.