• Journal of IKEEE
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• v.26 no.1
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• pp.95-103
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• 2022

In this paper, the efficiency of a sensorless method with square-wave injection for a low-cost inverter, so called B4 inverter is presented. This inverter comprises only 4 switches to reduce system cost. It is distinguished from the conventional B6 inverter that has 6 of switching elements. The B4 inverter, injected a 1 kHz of harmonic wave, has been modelled using the functions and library in Matlab/Simulink. This paper described each component of sensorless algorithm. Among them, the Notch Filter is used to extract the harmonic component of the phase current and a second-order low-pass filter was used to reduce the ripple of the estimated speed. It is shown through simulation that the rotor angle of a permanent magnet synchronous motor is detected by multiplying the current waveform extracted using the notch filter by the harmonic voltage. The feasibility of the proposed method is shown through Simulink simulation.

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.247-260
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• 2022

This paper investigates plans to expand distribution channels for books by installing a book vending machine at convenience stories for the vitalization of the publishing culture and industry. After establishing the meaning of convenience stories and the concept of a book vending machine, the researcher identified a need for the installation and management of a book vending machine at convenience stories. This plan will promote fairness and transparency in book sales through the convenience store system and push forward outsourcing between the publishing industry and the convenience store industry, the expansion of omnichannel service for consumers, and experiential values for clients to increase their customer satisfaction. The composition of the book vending machine will take the smart library form for its management with a universal design applied to a kiosk program. In the study, the researcher schematized this process and conducted a survey with 310 adults to search for practical management plans for a book vending machine. In the future, more research on the diversification of sales and distribution channels for publications such as the installation of a book vending machine at convenience stores will hopefully contribute to the growing amount of reading per capita and promotion of a reading environment for people according to the vitalization of the publishing culture and industry.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.459-461
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• 2022

One of the big differences between Network-on-Chip (NoC) and the existing parallel processing system based on an off-chip network is that data packet routing is performed using a centralized control scheme. In such an environment, the best-effort packet routing problem becomes a real-time assignment problem in which data packet arriving time and processing time is the cost. In this paper, the Hungarian algorithm, a representative computational complexity reduction algorithm for the linear algebraic equation of the allocation problem, is implemented in the form of a hardware accelerator. As a result of logic synthesis using the TSMC 0.18um standard cell library, the area of the circuit designed through case analysis for the cost distribution is reduced by about 16% and the propagation delay of it is reduced by about 52%, compared to the circuit implementing the original operation sequence of the Hungarian algorithm.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.133-139
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• 2024

The educational situation, which resulted from the announced self-isolation regime, intensified the forced decisions on the organization of the distance educational process. The study is topical because of the provision of distance learning based on the experience of Kyiv National University of Culture and Arts. The study was conducted in three stages. Systemic, socio-communicative, competence approaches, sociological methods (questionnaires and interviews) were chosen as methodological tools of the research. The results of a survey of teachers and entrants to higher education institutions on the topic "Using social networks and digital platforms for online classes under the conditions of quarantine restrictions" allowed to scientifically substantiate the need for deeper knowledge of such tools as Google Meet (79%), Zoom (13.78%) and Google Classroom (11.62%), which are preferred by entrants. Almost a third of entrants (34.26%) noted the lack of scientific and methodological support for learning the subjects. The study showed high efficiency of messengers in distance education. The study found that in the process of organizing communication in the student-teacher system, it is necessary to take into account the priority of Telegram on the basis of which it is necessary to implement a chatbot for convenient and effective exchange of information about the educational process. Further research should focus on the effectiveness of the use of Telegram. The effectiveness of using chatbots should also be considered. Chatbots can be used to automate routine components of the learning process.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.3
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• pp.551-562
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• 2024

This study relates to a method and device for extracting and tracking moving objects. In particular, objects are extracted using different images between adjacent images, and the location information of the extracted object is continuously transmitted to provide accurate location information of at least one moving object. It relates to a method and device for extracting and tracking moving objects based on tracking moving objects. People tracking, which started as an expression of the interaction between people and computers, is used in many application fields such as robot learning, object counting, and surveillance systems. In particular, in the field of security systems, cameras are used to recognize and track people to automatically detect illegal activities. The importance of developing a surveillance system, that can detect, is increasing day by day.

• Journal of Korean Medicine Rehabilitation
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• v.34 no.3
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• pp.53-63
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• 2024

Objectives This study aims to analyze the effectiveness of manual therapy for the treatment of plantar fasciitis by reviewing existing randomized controlled trials. Specifically, it seeks to identify various manual therapy techniques and evaluate their applicability in clinical settings. Methods The study reviewed literature from six databases (PubMed, the Cochrane Library, China National Knowledge Infrastructure, ScienceON, Research Information Sharing Service, Korean studies Information Service System) up to April 2024. Studies were selected based on criteria including randomized controlled trials involving manual therapy for plantar fasciitis. Results An analysis of ten studies involving 714 patients revealed the use of techniques such as joint mobilization, muscle relaxation, and pressure point techniques. Manual therapy was found to be more effective in reducing pain than both extracorporeal shock wave therapy and routine physical therapy alone. However, caution is needed in generalizing these results due to the limited number of studies analyzed. No significant adverse effects were reported. Conclusions Manual therapy demonstrates potential as an effective treatment for plantar fasciitis, offering benefits in pain management and functional recovery. However, further high-quality randomized controlled trials are necessary to strengthen the clinical evidence and establish standardized treatment protocols.

• Korean Journal of Chemical Engineering
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• v.39
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• pp.1004-1010
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• 2022

Ceramides are a major lipid class known to play an essential role in maintaining skin function. Thus, efforts have been made to produce ceramides and ceramide precursors in large quantities for industrial applications. The yeast Wickerhamomyces ciferrii, a natural producer of the ceramide precursor tetraacetyl phytosphingosine (TAPS), has been isolated and engineered through various mutagenesis approaches aiming to enhance TAPS production. Herein, a high-throughput screening platform for isolating W. ciferrii mutants with improved TAPS production is described. A fluorescence-mediated reporter system that allows initial quantification of TAPS content in yeast cells based on BODIPY staining was developed. The optimal concentration of BODIPY for monitoring intracellular TAPS levels in W. ciferrii was 400 ㎍/L, as shown by a linear correlation between the actual TAPS levels and mean fluorescence intensities. Fluorescence-activated cell sorting was used for isolating high TAPS-producing strains from an ethyl methanesulfonate-induced mutant library. After several rounds of sorting, mutants exhibiting a high-TAPS phenotype were isolated, and the M40 strain with the highest TAPS titer was chosen for large-scale cultivation. The influence of different carbon sources for optimizing TAPS production was also evaluated using the M40 strain. A maximum production yield of 5.114 g/L of ceramide precursors, including TAPS and triacetyl phytosphingosine, was achieved with the supplementation of molasses. This novel platform enables rapid screening of high TAPS-producing strains using the common dye BODIPY and can be easily extended for the development of mutants with high productivity of ceramide precursors in yeast and other microorganisms.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.112-118
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• 2002

Sporulation in the fission yeast Schizosaccharomyces pombe has been regarded as an important model of cellular development and differentiation. S. pombe cells proliferate by mitosis and binary fission on growth medium. Deprivation of nutrients especially nitrogen sources, causes the cessation of mitosis and initiates sexual reproduction by matting between two sexually compatible cell types. Meiosis is then followed in a diploid cell in the absence of nitrogen source. DNA fragment complemented with the mutations of sporulation gene was isolated from the S. pombe gene library constructed in the vector, pDB 248' and designated as pDB(spo5)1. We futher analyzed six recombinant plasmids, pDB(spo5)2, pDB(spo5)3, pDB(spo5)4, pDB(spo5)5, pDB (spo5)6, pDB(spo5)7 and found each of these plasmids is able to rescue the spo5-2, spo5-3, spo5-4, spo5-5, spo5-6, spo5-7 mutations, respectively. Mapping of the integrated plasmid into the homologous site of the S. pombe chromosomes demonstrated that pDB(spo5)1, and pDB(spu5)Rl contained the spo5 gene. Transcripts of spo5 gene were analyzed by Northern hybridization. Two transcripts of 3.2 kb and 2.5kb were detected with 5kb Hind Ⅲ fragment containing a part of the spo5 gene as a probe. The small mRNA(2.5kb) appeared only when a wild-type strain was cultured in the absence of nitrogen source in which condition the large mRNA (3.2kb) was produced constitutively. Appearance of a 2.5kb spo5-mRNA depends upon the function of the meil, mei2 and mei3 genes.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.181-186
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• 2003

The satellite navigation system is widely used for identifying a user's position regardless of weather or geographic conditions and also make effect on new technology of marine LBS(Location Based Service), which has the technology of geographic information such as the ENC. Generally, there are conceivable systems of marine LBS such as ECDIS, or ECS that use the ENC itself with powerful processor in installed type on ships bridge. Since the ENC is relatively heavy structure with dummy format for data transfer between different systems, we should reduce the ENC to small and compact size in order to use it in mobile platform. In this paper, we assumed that the mobile system like PDA, or Webpad can be used for small capability of mobile platform. However, the ENC should be updated periodically by update profile data produced by HO. If we would reduce the ENC without a consideration of update, we could not get newly updated data furthermore. As summary, we studied considerations for ENC reduction with update capability. It will make the ENC be useful in many mobile platforms for various applications.

• The Journal of Internal Korean Medicine
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• v.45 no.3
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• pp.335-341
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• 2024

Objectives: Patients with cancer eventually fail to respond to therapy when malignant cells develop effective ways to evade immunosurveillance. Conventional cancer treatments, such as radiation therapy and chemotherapy, aim to cure the disease or prolong the patient's life. However, the toxicity and side effects of conventional treatments limit their efficacy. Herbal medicine is a typical complementary and integrative form of medicine for cancer treatment in Asia. This protocol evaluates the effectiveness of herbal medicines in improving the immune function of patients with cancer. Methods: The following electronic databases will be searched: MEDLINE via PubMed, EMBASE via Elsevier, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure (CNKI), and Korean databases including Regional Information Sharing Systems (RISS), National Digital Science Library (NDSL), and Oriental Medicine Advanced Searching Integrated System (OASIS). Additionally, prospective randomized controlled trials that evaluate the effectiveness of herbal medicines on immune function in patients with cancer will be included in this review. All outcomes related to the immune function of patients with cancer (e.g., CD3, CD4, CD8, CD4/CD8 ratio, CD19 (B cells), dendritic cells (CD11), CD56 (NK cells), and macrophages) will be included in this review. Results: This review is expected to provide data on the effectiveness of herbal medicines on improving immune functions in patients with cancers. Conclusion: This systematic review will help patients and clinicians establish new management options for cancer treatment.