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Radioanalytical and Spectroscopic Characterizations of Hydroxo- and Oxalato-Am(III) Complexes (방사분석과 분광학을 이용한 Am(III) 가수분해와 옥살레이트 착물 화학종 연구)

  • Kim, Hee-Kyung;Cho, Hye-Ryun;Jung, Euo Chang;Cha, Wansik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.4
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    • pp.397-410
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    • 2018
  • When considering the long-term safety assessment of spent-nuclear fuel management, americium is one of the most radio-toxic actinides. Although spectroscopic methods are widely used for the study of actinide chemistry, application of those methods to americium chemistry has been limited. Herein, we purified $^{241}Am$ to obtain a highly pure stock solution required for spectroscopic studies. Quantitative and qualitative analyses of purified $^{241}Am$ were carried out using liquid scintillation counting, and gamma and alpha radiation spectrometry. Highly sensitive absorption spectrometry coupled with a liquid waveguide capillary cell and time-resolved laser fluorescence spectroscopy were employed for the study of Am(III) hydrolysis and oxalate (Ox) complexation. $Am^{3+}$ ions under acidic conditions exhibit maximum absorbance at 503 nm, with a molar absorption coefficient of $424{\pm}8cm^{-1}{\cdot}M^{-1}$. $Am(OH)_3(s)$ colloidal particles formed under near neutral pH conditions were identified by monitoring the absorbance at around 506-507 nm. The formation of ${Am(Ox)_3}^{3-}$ was detected by red-shifts of the absorption and luminescence spectra of 4 and 5 nm, respectively. In addition, considerable enhancements of the luminescence intensities were observed. The luminescence lifetime of ${Am(Ox)_3}^{3-}$ increased from 23 to 56 ns, which indicates that approximately six water molecules are replaced by carboxylate ligands in the inner-sphere of the Am(III). These results suggest that ${Am(Ox)_3}^{3-}$ is formed through the bidentate coordination of the oxalate ligands.

Synthesis and Structural Characterization of β-Carboline Compounds (β-카볼린 화합물의 합성 및 구조분석)

  • Byeon, Hong-Ju;Han, Min-Hui;Moon, Gi-Seong;Jung, Kyung-Hwan;Lee, Hyang-Yeol
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.2
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    • pp.676-684
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    • 2019
  • The Pictet-Spengler reactions have widely known for the organic synthesis or biosynthesis of biologically active compounds, tetrahydro-${\beta}$-carbolines. We have developed the simple and efficient synthetic method for the synthesis of ${\beta}$-carbolines in water. Their chemical structures were characterized by nmr and UPLC/MS/QTOF. Calculated masses of compound 1 ($C_{17}H_{17}N_2$ 249.1392), 2 ($C_{17}H_{23}N_2$ 255.1861), 3 ($C_{19}H_{21}N_2O_3$ 325.1552) and 4 ($C_{19}H_{19}N_2O$ 279.1497) were almost identical with the detected masses of compound 1 (249.1315), 2 (255.1789), 3 (325.1460) and 4 (279.1364) respectively. Those synthesized four compounds showed strong antibiotic activity against the common E. coli.

The Study on the Construction Criteria and Dujabee Technique of the Construction of the Cheomseongdae (첨성대축조 규준방식과 드잡이기술에 대한 기술사적 접근 연구)

  • Kim, Derk Moon
    • Korean Journal of Heritage: History & Science
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    • v.45 no.4
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    • pp.92-103
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    • 2012
  • The Cheomsungdae was built in the Silla dynasty during the reign of queen Seondeok. It has a round cylindrical structure with a flowing curved fa ade. The identity of the Cheomsungdae has not been revealed since there is not much historical evidence or documents about the building. This study is trying to investigate the building technique and method from the technical point of view of the past when it was constructed. There have been much work and studies done for the Cheomsungdae, but not much were focusing on the technical aspects of the building. In addition there are many questions and doubts about the hypothesis of the building technique of Cheomsungdae since there aren't any remaining documents or historical evidence supporting it. Among many questions, we think that the discussion on falsework technique is not considering traditional construction method of the Dujabee (a traditional construction technique using various tools and equipment for the stability of the building) technique. Therefore, it is hard to identify them as reliable historical facts. As the result of the study, we want to provide the basic data on the construction techniques of Korean traditional architecture and broaden the study scope of technical history by narrowing the errors. The study could be summarized into three points. 1. The historical architecture Cheomseongdae was constructed by using traditional crane techniques such as a Noklo (pulley ladder). Cheomseongdae was re-evaluated as a high level technology for the history of architecture. 2. The benchmark method on Cheomseongdae construction has been applied with a precise scientific method based on the geometrical principals using the central axis. 3. In terms of the history of Korean traditional architecture technology, as there aren't many studies done we proposed various basic data for the traditional crane techniques and criteria of Korean traditional architecture technology. We could expect various and active studies for the technical approach of the history of architecture.

The Hardware Design of Effective Deblocking Filter for HEVC Encoder (HEVC 부호기를 위한 효율적인 디블록킹 하드웨어 설계)

  • Park, Jae-Ha;Park, Seung-yong;Ryoo, Kwang-ki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.755-758
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    • 2014
  • In this paper, we propose effective Deblocking Filter hardware architecture for High Efficiency Video Coding encoder. we propose Deblocking Filter hardware architecture with less processing time, filter ordering for low area design, effective memory architecture and four-pipeline for a high performance HEVC(High Efficiency Video Coding) encoder. Proposed filter ordering can be used to reduce delay according to preprocessing. It can be used for realtime single-port SRAM read and write. it can be used in parallel processing by using two filters. Using 10 memory is effective for solving the hazard caused by a single-port SRAM. Also the proposed filter can be used in low-voltage design by using clock gating architecture in 4-pipeline. The proposed Deblocking Filter encoder architecture is designed by Verilog HDL, and implemented by 100k logic gates in TSMC $0.18{\mu}m$ process. At 150MHz, the proposed Deblocking Filter encoder can support 4K Ultra HD video encoding at 30fps, and can be operated at a maximum speed of 200MHz.

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The Role of Clients in Software Projects with Agile Methods (애자일 방법론을 사용한 소프트웨어 프로젝트에서의 사용자 역할 분석)

  • Kim, Vladimir;Cho, Wooje;Jung, Yoonhyuk
    • Journal of Intelligence and Information Systems
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    • v.25 no.3
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    • pp.141-160
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    • 2019
  • Agile methodologies in software development, including the development of artificial intelligence software, have been widespread over the past several years. In spite of the popularity of agile methodologies in practice, there is a lack of empirical evidence to identify determinants of success of software projects in which agile methods are used. To understand the role of clients in software project where agile methods are used, we examine the effect of client-side factors, including lack of user involvement, unrealistic client expectations, and constant changes of requirements on project success from practitioners' perspective. Survey methods are used in this study. Data were collected by means of online survey to IT professionals who have experience with software development methodologies, and ordered logit regression is used to analyze the survey data. Results of our study imply the following managerial findings. First, user involvement is critical to project success to take advantage of agile methods. Second, it is interesting that, with an agile method, constant changes of client's requirements is not a negative factor but a positive factor of project success. Third, unrealistic client expectations do negatively affect project success even with agile methods.

A Study on the Vulnerability Management of Internet Connection Devices based on Internet-Wide Scan (인터넷 와이드 스캔 기술 기반 인터넷 연결 디바이스의 취약점 관리 구조 연구)

  • Kim, Taeeun;Jung, Yong Hoon;Jun, Moon-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.504-509
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    • 2019
  • Recently, both wireless communications technology and the performance of small devices have developed exponentially, while the number of services using various types of Internet of Things (IoT) devices has also massively increased in line with the ongoing technological and environmental changes. Furthermore, ever more devices that were previously used in the offline environment-including small-size sensors and CCTV-are being connected to the Internet due to the huge increase in IoT services. However, many IoT devices are not equipped with security functions, and use vulnerable open source software as it is. In addition, conventional network equipment, such as switches and gateways, operates with vulnerabilities, because users tend not to update the equipment on a regular basis. Recently, the simple vulnerability of IoT devices has been exploited through the distributed denial of service (DDoS) from attackers creating a large number of botnets. This paper proposes a system that is capable of identifying Internet-connected devices quickly, analyzing and managing the vulnerability of such devices using Internet-wide scan technology. In addition, the vulnerability analysis rate of the proposed technology was verified through collected banner information. In the future, the company plans to automate and upgrade the proposed system so that it can be used as a technology to prevent cyber attacks.

Teaching and Learning of University Calculus with Python-based Coding Education (파이썬(Python) 기반의 코딩교육을 적용한 대학 미적분학의 교수·학습)

  • Park, Kyung-Eun;Lee, Sang-Gu;Ham, Yoonmee;Lee, Jae Hwa
    • Communications of Mathematical Education
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    • v.33 no.3
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    • pp.163-180
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    • 2019
  • This study introduces a development of calculus contents which makes to understand the main concepts of calculus in a short period of time and to enhance problem solving and computational thinking for complex problems encountered in the real world for college freshmen with diverse backgrounds. As a concrete measure, we developed 'Teaching and Learning' contents and Python-based code for Calculus I and II which was used in actual classroom. In other words, the entire process of teaching and learning, action plan, and evaluation method for calculus class with Python based coding are reported and shared. In anytime and anywhere, our students were able to freely practice and effectively exercise calculus problems. By using the given code, students could gain meaningful understanding of calculus contents and were able to expand their computational thinking skills. In addition, we share a way that it motivated student activities, and evaluated students fairly based on data which they generated, but still instructor's work load is less than before. Therefore, it can be a teaching and learning model for college mathematics which shows a possibility to cover calculus concepts and computational thinking at once in a innovative way for the 21st century.

Effects of Magnolia Officinalis Bark Extract on Improvement of Lip Wrinkles (요엽후박나무 추출물의 입술 주름 개선에 대한 연구)

  • Lee, Seonju;Kim, Mina;Park, Sung Bum;Kim, Ki Young;Park, Sun-Gyoo;Kim, Mi-Sun;Kang, Nae-Gyu
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.1
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    • pp.95-103
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    • 2019
  • Lips have a defect in maintenance of moisture due to their thin layer. As aging progresses, lips lose volume and redness, and become wrinkled. Fat grafting and filler surgery have been used to achieve attractive lips, but little research has been reported to develop better materials to replace the present methods. Recently, a study suggests that the increase of adipocyte number can be enhancing the expansion endogenous fat. In previous study, we identified that the efficacy of Magnolia officinalis bark extract (MOBE) was effective on the induction of adipogenic differentiation. In this study, we confirmed that MOBE enhanced the differentiation of human adipose-derived stem cells on the fat mimic 3D structure built by 3D bioprinting method From further experiments in human, we established a method to quantify the severity of lip wrinkle by measurement of standard deviation of gray value using Image J software. Finally, we found that topical treatment with 1% MOBE formulated lip balm significantly improved the lip wrinkle after using for 12 weeks. In conclusion, these findings suggest that MOBE has great potential, as a cosmetic ingredient, to reduce the lip wrinkle through the effect of promoting adipogenic differentiation.

Analysis on Displacement Characteristics of Slow-Moving Landslide on a slope near road Using the Topographic Map and Airborne LiDAR (수치지형도와 항공 LiDAR를 이용한 도로인접 사면 땅밀림 발생지 변위 특성 분석)

  • Seo, Jun-Pyo;Kim, Ki-Dae;Woo, Choong-Shik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.5
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    • pp.27-35
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    • 2019
  • The purpose of this study is to analyze the displacement characteristics in slow-moving landslide area using digital elevation model and airborne LiDAR when unpredictable disaster such as slow-moving landslide occurred. We also aimed to provide basic data for establishing a rapid, reasonable and effective restoration plan. In this study, slow-moving landslide occurrence cracks were selected through the airborne LiDAR data, and the topographic changes and the scale of occurrence were quantitatively analyzed. As a result of the analysis, the study area showed horseshoe shape similar to the general form of slow-moving landslide occurrence in Korea, and the direction of movement was in the north direction. The total area of slow-moving landslide damage was estimated to about 2.5ha, length of landsldie scrap 327.3m, average width 19.3m, and average depth 8.6m. The slow-moving landslides did not occur on a large scale but occurred on the adjacent slope where roads were located, caused damage to retaining walls and roads. The field survey of slow-moving landslides was limited by accessibility and safety issues, but there was an advantage that accurate analysis was possible through the airborne LiDAR. However, because airborne LiDAR has costly disadvantages, it has proposed a technique to mount LiDAR on UAV for rapidity, long-term monitoring. In a slow-moving landslide damage area, information such as direction of movement of cracks and change of scale should be acquired continuously to be used in restoration planning and prevention of damage.

E-Governance Practices in Developing Countries. Its Benefits and Challenges. -The Case of Pakistan- (개발도상국의 전자정부 시행에 따른 장점과 문제 -파키스탄 중심으로-)

  • Aftab, Muhammad
    • Industry Promotion Research
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    • v.4 no.1
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    • pp.79-86
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    • 2019
  • The quality of service delivery by governments to their citizens is a subject of concern in the contemporary society. E-governance is a critical aspect that is transforming government operation and service delivery to citizens and other bodies through application of information technology. This research explores the state of e-governing focusing on nations that are developing with special attention to Pakistan. The difficulties and benefits encountered are identified. The results are vital for implementers of e-governing systems in these countries. The methodology applied entails a secondary research that involves analysis and synthesis of literature relating the research topic. The results reveal that Pakistan has made incredible steps in setting up e-governance systems with growth in internet use and access of data from a digital platform. The findings reveal that e-government is associated with multiple benefits including enhanced quality of services, cost efficiency in service provision, enhance transparency and elimination of corruption, provide the basis for eradication of poverty, boost economic stability of a country, and provide room for direct democracy. The research also found that developing countries experience challenges in form of financial constraints, poor ICT infrastructure, illiteracy on e-government, political consensus constraints, legal obstacles, social and cultural constraints. E-government has the capability to transform the quality of governance provided by governments, and policymakers and implementers should address the constraints that act as a hindrance to its implementation.