• Journal of IKEEE
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• v.25 no.1
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• pp.156-167
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• 2021

In this paper, we propose a digital transceiver unit design for in-building of 5G optical repeaters that extends the coverage of 5G mobile communication network services and connects to a stable wireless network in a building. The digital transceiver unit for driving the proposed 5G optical repeater is composed of 4 blocks: a signal processing unit, an RF transceiver unit, an optical input/output unit, and a clock generation unit. The signal processing unit plays an important role, such as a combination of a basic operation of the CPRI interface, a 4-channel antenna signal, and response to external control commands. It also transmits and receives high-quality IQ data through the JESD204B interface. CFR and DPD blocks operate to protect the power amplifier. The RF transmitter/receiver converts the RF signal received from the antenna to AD, is transmitted to the signal processing unit through the JESD204B interface, and DA converts the digital signal transmitted from the signal processing unit to the JESD204B interface and transmits the RF signal to the antenna. The optical input/output unit converts an electric signal into an optical signal and transmits it, and converts the optical signal into an electric signal and receives it. The clock generator suppresses jitter of the synchronous clock supplied from the CPRI interface of the optical input/output unit, and supplies a stable synchronous clock to the signal processing unit and the RF transceiver. Before CPRI connection, a local clock is supplied to operate in a CPRI connection ready state. XCZU9CG-2FFVC900I of Xilinx's MPSoC series was used to evaluate the accuracy of the digital transceiver unit for driving the 5G optical repeater proposed in this paper, and Vivado 2018.3 was used as the design tool. The 5G optical repeater digital transceiver unit proposed in this paper converts the 5G RF signal input to the ADC into digital and transmits it to the JIG through CPRI and outputs the downlink data signal received from the JIG through the CPRI to the DAC. And evaluated the performance. The experimental results showed that flatness, Return Loss, Channel Power, ACLR, EVM, Frequency Error, etc. exceeded the target set value.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.789-794
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• 2003

Purpose : We intended to evaluate the effect of hypoxia-ischemia on extracellular striatal monoamine metabolism in neonatal rat brains by in vivo microdialysis. Methods : The right common carotid arteries of five or six-day old rats were surgically ligated, and the probes for microdialysis were inserted into the right striatum with stereotaxic instrument. After stabilization for two hours, artificial cerebrospinal fluid was infused via the probe for microdialysis and samples were collected during hypoxia-ischemia and recovery periods at 20 minute intervals. The concentrations of DA(dopamine), DOPAC(3,4-di-hydroxyphenyl acetic acid), HVA(homovanillic acid), NE(norepinephrine), and 5-HIAA(5-hydroxy indole-acetic acid) were measured by HPLC(high performance liquid chromatography) and the changes were analysed. Results : The striatal levels of dopamine metabolites such as DOPAC and HVA, were significantly decreased during hypoxia-ischemia, and increased to their basal level during reoxygenation(P<0.05). Dopamine mostly increased during hypoxia but statistically not significant(P>0.05). DOPAC showed the most remarkable decrease($23.0{\pm}4.2%$, P<0.05), during hypoxia-ischemia and increase to the basal levels during reoxygenation($120.8{\pm}54.9%$, P<0.05), and HVA showed the same pattern of changes as those of DOPAC during hypoxia-ischemia($35.3{\pm}7.6%$ of basal level, P<0.05) and reoxygenation ($105.8{\pm}32.3%$). However, the level of NE did not show significant changes during hypoxia-ischemia and reoxygenation. The levels of 5-HIAA decreased($74.9{\pm}3.1%$) and increased($118.1{\pm}7.8%$) during hypoxia-ischemia and reoxygenation, respectively(P<0.005). Conclusion : Hypoxia-ischemia had a significant influence on the metabolism of striatal monoamine in neonatal rat brains. These findings suggest that monoamine, especially dopamine, and its metabolites could have a significant role in the pathogenesis of hypoxic-ischemic injury of neonatal rat brains.

• Radiation Oncology Journal
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• v.17 no.4
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• pp.281-286
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• 1999

Purpose : Brain metastases are the most frequent metastatic neurologic complication of systemic cancer. Even if the prognosis of brain metastases is grave, with available treatments, most patients experience effective palliation of neurologic symptoms and meaningful extension of life. We evaluated the clinical features and prognostic factors of the patients who were diagnosed as solid tumors with brain metastasis and received radiotherapy for brain metastases. Materials and Methods: Between January 1987 and January 1998, 71 patients with brain metastases from solid malignancy were included. We reviewed neurologic symptoms and signs of patients and evaluated improvememt of neurologic symptoms and signs. Survival durations after brain metastasis were ana lysed according to several factors such as age, performance status, primary malignancies, the pre-sence of brain metastasis at initial diagnosis of primary tumor, multiplicity of brain metastass, the presence of metastases other than brain, and treatment method. Results: Frequent symptoms associated with brain metastasis were headache (47.9$\%$), motor weakness (40.8$\%$), nausea and vomiting (19.7$\%$) and mental change (19.7%). Palliation of these symptoms was accomplished in 64.9$\%$ of cases. The overall median survival time was 16 weeks and 1- and 2-year survival rates were 15.0$\%$ and 5.1$\%$ respectively. Patients without extracranial metastases (n=27) had longer median survival than patients with extracranial metastases (33 weeks vs 10 weeks, p=0.0018). In patients with single brain metastasis (n=37), the median survival time was longer in patients treated with surgery plus radiotherapy than in patients treated with radiotherapy alone (40 weeks vs 16 weeks, p=0.0438). Conclusion: Patients who has brain metastases only constitute a prognostically favorable group and they may be benefited from radiotherapy and surgery if indicated.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.100-107
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• 2002

Purpose : The aim of this retrospective study was to assess the treatment results of 30 patients with pineal region tumors who were underwent radiation therapy under the diagnosis by either CT or MRI. There was no histological verification. We analyzed the prognostic factors that have a significant effect on the overall survival (OS) and disease free survival (DFS) rates. Materials and Methods : A total 30 patients with pineal region tumors were treated between March 1983 and August 1995. After a trial radiation therapy of $20\~30\;Gy/2\~3$ weeks, the patients were evaluated for their clinical response and radiological response by either CT or MRI and the final treatment direction was then decided. According to their response to the trial radiation therapy and the involved site, radiation treatment was given in various fields i.e., local, ventricle, whole brain and craniospinal field. The radiation dose ranged from 40.8 to 59.4 Gy (Median 50.4 Gy). The median follow up was 36.5 months $(4\~172\;months)$. Results : An improvement or stability in the clinical symptoms was observed in 28 patients $(93.3\%)$ after the trial RT. Nineteen patients $(63.3\%)$ showed a partial or complete response by CT or MRI. The two-year and five-year survival rates of the patients were $66.7\%$ and $55.1\%$, respectively. No significant difference in the survival rates according to the degree of the radiological response was abserved after the trial RT. The results of univariate analysis showed that age, the primary site, the performance status $(KPS\geq70)$, the degree of response after completing RT and the RT field were significant prognostic factors affecting the survival and disease free survival rates (p<0.05). Conclusion : The clinical and histological characteristics of pineal region tumors are quite complex and diverse. Therefore, it is difficult to predict the histological diagnosis and the possibility of radiocurability only with the initial response to RT. We think that the development of less invasive histological diagnostic techniques and tailored treatment to the histological type of each tumor are needed.

• Cartoon and Animation Studies
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• s.35
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• pp.291-312
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• 2014

This study is based on the theory of R.Caillois about element of play which is motivated to infant for studying Hangul. The ultimate goal of play has to be accompanied by pleasure. And learning means permanent changes from experiences for the individual's. Play and learning, these two elements are united to the genre of serious game since the GBL (game based learning) was lead. Most importantly, in order to achieve their own Hangul learning is the fun. Coupled with fun and learning has an important issue for flow because concentration is low in infants than adults. In this case study is to know about fun factor has been applied effectively to Hangul serious mobile game. 20 Infant Hangul mobile serious games of Google Android mobile game section were selected as a case study based on more than 10,000 downloads and user's review rate by April 22, 2014. After that is currently available on the market can play a variety of cases of infant learning Hangul from previous research of R.Caillois offers four categories of play. R.Caillois of Agon, Mimicry, Alea, Ilinx have unique characteristics in comparison with its functional characteristics Hangul four are present any role in Hangul serious mobile games. As a result of the cases selected and the rules of the game will include a maximum of two of the most common types of Agon. Each attribute of the play, rather than one single factor is applied to four kinds of game play performance when properties are distributed to experience together gave the best flow. As a result of this study will be a based research for infants Hangul serious mobile game reflects the properties of the elements of a fun game that you want to combine learning.

• The Journal of Society for e-Business Studies
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• v.21 no.3
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• pp.51-78
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• 2016

Online-to-offline (O2O) commerce is the new trend that merges online commerce with traditional industries in various fields. The primary purpose of this paper is to find out which factors influence customers' intention to switch from call-based driver-for-hire services to O2O app-based services. This study used variables and factors based on Theory of Switching Intention, and Extended Unified Theory of Acceptance and Use of Technology in order to design research questions. We surveyed 500 users of call-based driver-for-hire services. According to the result of this study, dissatisfaction with the current call-based driver-for-hire services is estimated to be a significant factor that strengthens customers' intention to switch from the call-based driver-for-hire services to the app-based services. Loyalty to the previous call-based driver-for-hire services was not seen as a crucial motivator that causes customers to switch to the new O2O driver service. Switching cost also did not play a key role in explaining the relationship between dissatisfaction with the current call-based service and the intention to use the new app-based service. Performance expectancy, easiness in use, the level of user's knowledge or available assistance in relation to the use of app-based services, and expectancy for reasonable price was found to have meaningful impacts on customers' intention to switch from the call-based driver-for-hire services to the app-based services. Age, gender and user experience on the new service were found incapable of moderating the relationship between aforementioned factors which influence customers' choice of the app-based driver-for-hire service, and customers' intent to switch to the app-based service.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.1
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• pp.52-62
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• 2017

Overseas landscape practices have already benefited from the awareness of BIM while landscape-related organizations are encouraging its use and the number of landscape projects using BIM is increasing. However, since BIM has not yet been introduced in the domestic field, this study investigated and analyzed overseas landscape projects and discussed the positive effects and implementation of BIM. For this purpose, landscape projects were selected to show three effects of BIM: improvement of design work efficiency, building of a platform for cooperation, and performance of topography design. These three projects were analyzed across four aspects of implementation methods: landscape information, 3D modeling, interoperability, and visualization uses of BIM. First, in terms of landscape information, a variety of building information was constructed in the form of 3D libraries or 2D CAD format from detailed landscape elements to infrastructure. Second, for 3D modeling, a landscape space including simple terrain and trees was modeled with Revit while elaborate and complex terrain was modeled with Maya, a professional 3D modeling tool. One integrated model was produced by periodically exchanging, reviewing, and finally combining each model from interdisciplinary fields. Third, interoperability of data from different fields was achieved through the unification of file formats, conversion of differing formats, or compliance with information standards. Lastly, visualized 3D models helped coordination among project partners, approval of design, and promotion through public media. Reviewing of the case studies shows that BIM functions as a process to improve work efficiency and interdisciplinary collaboration, rather than simply as a design tool. It has also verified that landscape architects could play an important role in integrated projects using BIM. Just as the introduction of BIM into the architecture, engineering and construction industries saw great benefits and opportunities, BIM should also be introduced to landscape architecture.

• Korean Journal of Heritage: History & Science
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• v.51 no.1
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• pp.32-47
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• 2018

The purpose of this study is to examine the vegetation maintenance project that was conducted as a part of the Official Development Assistance (ODA) project for the historic site of Angkor, to analyze the aspects and characteristics of the project, and to derive implications for the establishment of future policies and strategies. First, the key words used in the vegetation maintenance project at the historic site of Angkor do not only refer to the concept of plants (and more specifically to 'trees') but also to the concept of heritage. In other words, the concept of heritage is not limited to architectural structures but is also intended to mean the vegetation and surroundings that form the historic site. Second, the expansion of the value of vegetation has contributed to the establishment of the basic principles of conservation based on the 'coexistence' between architectural structures and vegetation; here, vegetation has come to be recognized as an 'essential' element in the conservation of historic sites. Third, the range of vegetation maintenance has expanded from each tree to the surroundings of the temples, and vegetation maintenance came to adopt 'integrative' and 'active' directions to improve not only the growth environment of the vegetation but also the viewing environment experienced by visitors. This change means that it is necessary for the historic site maintenance project to comprehensively deal with the temples and their surrounding areas. Fourth, for the effective performance of the ODA project, the role of the International Coordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC-Angkor), under the influence of UNESCO, was expanded from an examination of the problems with the existing projects to a search for solutions to technical consultation and supervision. This implies that, in order to perform the ODA project in a way that is appropriate to the local conditions, it is important to reach gradual and phased agreements with ICC-Angkor.

• Journal of Venture Innovation
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• v.1 no.2
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• pp.13-34
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• 2018

In this case, research has been conducted to verify that the purpose of establishing a reputation for establishing a reputation for identifying brand equity is research and investigation in the context of establishing a reputation for establishing a reputation, and conducting research on CSR activities that are essential to the essential activities of companies. The survey conducted a survey on behalf of the National Center for Adult Women and Girls and Girls ' Generation, using the final round of Section 305 to develop a series of findings, including the analysis of the feasibility analysis, feasibility analysis, reliability, correlation analysis, and factors analysis. A summary of the effects of research on corporate reputation on corporate reputation according to corporate CSR activities is as follows. 1st. Brand equity will have a positive effect on the Company's reputation. The hypothesis had a significant impact on brand recognition, brand loyalty, and perceived quality, but did not have significant impact on the brand image. 2st. Brand equity will have a positive effect on ethical responsibility. The hypothesis had a significant impact on brand recognition, brand loyalty, and perceived quality, but did not have significant impact on the brand image. 3st, the brand equity will have a positive effect on the benefit of the benevolent. The hypothesis had a significant impact on brand recognition, brand loyalty, and perceived quality, but did not have significant impact on the brand image. 4st, The theory that the influence of positive(+) will affect the company's reputation has a significant impact on both ethical and philanthropic factors. 5st. The ethical responsibility was found to have no effect on the usefulness of the brand between brand assets and corporate reputation. 6st. The philanthropic responsibility was partly attributable to the fact that there was a substitution between brand equity and corporate reputation. In sum, the company needs to prioritize its brand recognition before establishing its reputation, and the reason why it should be implemented is that the other elements of the brand equity should be evaluated with the presence of other elements of the brand equity, thereby ensuring continued compliance with continuous CSR activities. As a result, consumers expect to see the performance-based role of the company as a strategic and long-term perspective, as consumers want to see the CSR activity and the corporate reputation in a long-term manner, as opposed to the financial responsibility and legal responsibilities of the past, as opposed to the past.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.497-507
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• 2012

This study aims to verify how the characteristics of organizational supporting unit affect the effectiveness of company-wide HRD Education & Training program. To achieve this objective, we performed an empirical analysis, with the characteristics of organizational supporting unit comprising supervisor's support, job support, and company support as independent variables, and with the level of reaction stage, learning stage, transfer stage, and result stage as dependent variables. Empirical data was collected during the period from August 16, 2011 to September 9, 2011 by sending out questionnaires to employees of 5 securities firms listed on KOSDAQ where online and offline education & training program is running year-round with headquarter in Seoul. A total of 340 questionnaires were sent out three times for the survey, and total of 164 questionnaires were sampled for the final analysis. According to the outcome of the analysis, regarding the first hypothesis that tries to reveal how the characteristics affect the level of reaction stage, it is verified that all of supervisor's support, job support and company support have positive impact on the level of reaction stage with p value less than 0.01. In regard to the second hypothesis that tries to see how the characteristics affect the level of learning stage, it is confirmed that supervisor's support, job support and company support have significant impact on the level of learning stage with p value less than 0.05 or 0.01, respectively. Concerning the third hypothesis that aims to investigate how the characteristics affect the level of transfer stage, it is appeared that all of supervisor's support, job support and company support have positive impact on the level of transfer stage. And lastly, as for the fourth hypothesis that tries to see how the characteristics affect the level of result stage, it is analyzed that supervisor's support, job support and company support have positive impact on the level of result stage with p value less than 0.01. This study reconfirm the outcomes of previous research, which is that the effectiveness of company-wide education & training program depends not only on the contents and quality of education & training program, but also more importantly on the role of organizational supporting unit, and the working environment where what is learned in classroom can be applied to real business. Companies or experts that run education & training program in real world should recognize that the performance of training is dependent more significantly on the characteristics of organizational supporting unit rather than the design or features of education & training program.