• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.69-77
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• 2009

Small size and low profile antenna for mobile vehicular-top-mounted is needed in satellite communication services such as DBS, Satellite Internet and VSAT. In middle latitudes, the development of an array antenna which has the conformal, low profile and 45 degree beam tilted configuration, and has the high gain with sharp beamwidth, low sidelobe and low loss is required for Ka band satellite communication. In this paper, in order to meet with these performances, an array antenna consisting of the vertical polarized waveguide longitudinal slots based on the leaky-wave mode of traveling wave antenna is proposed. Especially, for the lower sidelobe level the radiation power control using a design method of the different slot width is proposed. An array antenna consisting of 32 leakywave elements is showing 34.4 dBi of gain, 3.6 degree of beamwidth, below than -25 dB of sidelobe level, 43 degree of beam tilt angle in center frequency 20.0 GHz. Feed network designed by waveguide cooperated feed shows good performance of wideband and low loss.

• Journal of Advanced Navigation Technology
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• v.8 no.2
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• pp.190-196
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• 2004

The development of a new hardware structure which can implement the viterbi algorithm efficiently is required for applications such as a software radio because the viterbi algorithm, which is an error correction code function for the second and the third generation of mobile communication, needs a lot of arithmetic operations. The length of K in the viterbi algorithm different from each standard, for examples, K=7 in case of IS-95 standard and GSM standard, and K=9 in case of WCDMA and CDMA2000. In this paper, we propose a new hardware structure of an adaptive viterbi decoder which can decode the constraint length in K=3~9 and the data rate in 1/2 ~ 1/3. Prototyping results targeted to Altera Cyclon EPIC20F400C8, shows that the proposed hardware structure needs maximum 19,276 logic elements and power dissipation of 222.6 mW.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.316-319
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• 2017

The antibiotic resistant genes (ARG) and mobile genetic elements (MGE) were investigated with the effluent of waste-water treatment plant (WWTP), and river waters of upstream and downstream in order to elucidate the effect of effluent on antibiotic resistance in a natural river. Total numbers of 134~183 of ARG and MGE were detected and the abundance of ARG and MGE was 0.063~0.422 copies per one of 16S rRNA gene in three water samples. Effluent sample contained the highest amount of the total number and abundance of ARG and MGE whereas total viable cells were observed in the lowest amount among the three samples. This indicated that the genes were originated from cells died during the wastewater treatment process. In addition, the co-relationship of abundance between ARG and MGE suggested that acquired resistance was a prevalent mechanism among the antibiotic-resistant bacteria existing in WWTP.

• Journal of Digital Convergence
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• v.19 no.7
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• pp.313-318
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• 2021

The purpose is to measure user experience in security-related services, focusing on Danggeun Market and Bungae Jangter, which are representative services in Korea among online trading of used goods. Using mobile applications, qualitative and quantitative research by conducting task experiments and surveys and in-depth interviews. As a result of the study, active interfaces are needed to make it easier for users to recognize safety and security services within current used trading platforms, a secure settlement method that benefits sellers, and services being provided to enhance security also need to consider graphical elements. This study is expected to help the continued development of safe used trading platforms considering security aspects on C2C-type platforms where buyers become sellers.

• Journal of the Korea Society of Computer and Information
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• v.24 no.7
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• pp.45-52
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• 2019

With the popularity of mobile Internet and smart phones, the domestic digital music access platform has entered a period of rapid development. Existing studies in the academic circle have shown that experience has a positive impact on user perception and loyalty. However, the research on the relationship between brand loyalty, user perception and user experience of Internet products has not received much attention. Starting from the brand loyalty theory and user experience theory, this paper explores the mechanism of user experience, user perception and brand loyalty of digital music access platform. Based on the development status of digital music access platform in China, the purpose is to explore how the user experience of the mainstream digital music access platform can affect Usefulness Perception, Epidemic Perception. And to explore how the Usefulness Perception, Epidemic Perception can affect users' brand loyalty. also further explore the role of users' perception in this process to understand the relationship between brand and user experience. In practical operations, 398 formal questionnaires were issued online to collect first-hand data, and reliability analysis, factor analysis, correlation analysis and hypothesis analysis were carried out successively on the data in the later stage. Through research, it is found that the user experience of digital music access platform has a partial significant impact on the perception and loyalty of applications. The visual presentation and emotional feelings of digital music access platform are positively correlated with the perceived usefulness of applications. The visual presentation and emotional feelings of digital music access platform are positively correlated with the perceived popularity of applications. The e perceived usefulness and perceived popularity of the digital music access platform are positively correlated with the loyalty of the application. Through this research, it has certain guiding significance to the promotion of digital music access platform's brand loyalty degree.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.125-133
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• 2021

With the advent of experience era, the user experience has attracted much attention in all walks of life. And the importance of user experience emphasize began to be emphasized. It analyzed the interfering factors of user experience of smart phone medical APP, and evaluated their relative importance. Then it made suggestions on the priority of medical APP development and provided reference for medical APP design optimization and service quality improvement. First of all, based on the related research about user experience theory, smartphone APP user experience and mobile medical APP, it summarized the user experience elements of smartphone medical APP. Secondly, 200 subjects in the 20-40 age group who chose smartphone download experience and used medical APP were surveyed to rate the effect of 18 factors. The results show that the factors such as product resources, medical advertising recommendations, doctor-patient interaction, emotional pleasure, easy to learn, and other factors have a significant impact on users' good experience when using app.

• Journal of Microbiology and Biotechnology
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• v.31 no.7
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• pp.949-955
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• 2021

Previously, our research group isolated Bifidobacterium breve IDCC4401 from infant feces as a potential probiotic. For this study, we evaluated the safety of B. breve IDCC4401 using genomic and phenotypic analyses. Whole genome sequencing was performed to identify genomic characteristics and investigate the potential presence of genes encoding virulence, antibiotic resistance, and mobile genetic elements. Phenotypic analyses including antibiotic susceptibility, enzyme activity, production of biogenic amines (BAs), and proportion of D-/L-lactate were evaluated using E-test, API ZYM test, high-performance liquid chromatography (HPLC), and D-/L-lactic acid assay respectively. The genome of B. breve IDCC4401 consists of 2,426,499 bp with a GC content of 58.70% and 2,016 coding regions. Confirmation of the genome as B. breve was provided by its 98.93% similarity with B. breve DSM20213. Furthermore, B. breve IDCC4401 genes encoding virulence and antibiotic resistance were not identified. Although B. breve IDCC4401 showed antibiotic resistance against vancomycin, we confirmed that this was an intrinsic feature since the antibiotic resistance gene was not present. B. breve IDCC4401 showed leucine arylamidase, cystine arylamidase, α-galactosidase, β-galactosidase, and α-glucosidase activities, whereas it did not show production of harmful enzymes such as β-glucosidase and β-glucuronidase. In addition, B. breve IDCC4401 did not produce any tyramine, histamine, putrescine, cadaverine, or 2-phenethylamine, which are frequently detected BAs during fermentation. B. breve IDCC4401 produced 95.08% of L-lactate and 4.92% of D-lactate. Therefore, our findings demonstrate the safety of B. breve IDCC 4401 as a potential probiotic for use in the food industry.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1420-1429
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• 2021

The safety of the probiotic strain Q180, which exerts postprandial lipid-lowering effects, was bioinformatically and phenotypically evaluated. The genome of strain Q180 was completely sequenced, and single circular chromosome of 3,197,263 bp without any plasmid was generated. Phylogenetic and related analyses using16S rRNA gene and whole-genome sequences revealed that strain Q180 is a member of Lactiplantibacillus (Lp., formerly Lactobacillus) plantarum. Antimicrobial resistance (AMR) genes were bioinformatically analyzed using all Lp. plantarum genomes available in GenBank, which showed that AMR genes are present differently depending on Lp. plantarum strains. Bioinformatic analysis demonstrated that some mobile genetic elements such as prophages and insertion sequences were identified in the genome of strain Q180, but because they did not contain harmful genes such as AMR genes and virulence factor (VF)- and toxin-related genes, it was suggested that there is no transferability of harmful genes. The minimum inhibition concentrations of seven tested antibiotics suggested by the European Food Safety Authority guidelines were slightly lower than or equal to the microbiological cut-off values for Lp. plantarum. Strain Q180 did not show hemolytic and gelatinase activities and biogenic amine-producing ability. Taken together, this study demonstrated the safety of strain Q180 in terms of absence of AMR genes and VF- and toxin-related genes as a probiotic strain.

• Journal of Industrial Convergence
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• v.19 no.1
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• pp.79-85
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• 2021

The purpose of this study was to investigate the existing augmented reality (AR) contents in education and to develop digital AR contents to promote the learning outcomes in nursing skills education. AR contents has been widely used in education such as children's books, coloring, or exhibition experiences, but rarely developed in nursing education. We wanted to develop AR contents on nursing skills which required memorization of complex contents. In order to improve nursing students' memorization skills, we developed AR techniques holding and executing cameras along with game elements of time and points. In order to give the effect of placing objects in front of the user's eyes, an augmented reality camera was applied, and a total of 40 levels were created to produce the sequence of nursing techniques. This study showed that learning contents in the medical field requiring expertise could be implemented as AR contents. The content developed in this study will be used as a learning aid for nursing students.

• Journal of Digital Convergence
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• v.18 no.12
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• pp.577-583
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• 2020

The learning and cognition of preschool children begins with the color of the object, and the game interface is the child's first impression of the game, so reasonable color design is needed. This article selects 10 educational mobile game for preschool children, extracts colors from the game interface and startup icons, and puts them into Photoshop to analyze the three elements of color hue, lightness, and saturation. Finally, three suggestions are put forward for the color design of game UI. 1.Choose a color similar to the actual color of the thing. 2. Choose warm colors according to your child's preferences. 3. When using contrasting colors, please reduce the brightness or purity of the colors. It is hoped that the research conclusions can provide reference materials for the color design of educational game UI for preschool children.