• Title/Summary/Keyword: Nature of science

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The Impact of Hardware Impairments and Imperfect Channel State Information on Physical Layer Security (하드웨어왜곡과 불완전한 채널상태정보가 물리계층보안에 미치는 영향)

  • Shim, Kyusung;Do, Nhu Tri;An, Beongku
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.4
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    • pp.79-86
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    • 2016
  • Physical layer security is cryptography technique to protect information by using physical nature of signals. Currently, many works on physical layer security have been actively researching while those researching models still have some problems to be solved. Eavesdropper does not share its channel state information with legitimate users to hide its presence. And when node transmits signal, hardware impairments are occurred, whereas many current researches assume that node model is ideal node and does not consider hardware impairments. The main features and contributions of this paper to solve these problems are as follows. First, our proposed system model deploys torch node around legitimate user to obtain channel state information of eavesdropper and considers hardware impairments by using channel state information of torch node. Second, we derive closed-form expression of intercept probability for the proposed system model. The results of the performance evaluation through various simulations to find out the effects on proposed system model in physical layer security show that imperfect channel state information does not effect on intercept probability while imperfect node model effects on intercept probability, Ergodic secrecy capacity and secrecy capacity.

Physiological Responses of Bupleurum latissimum Nakai, Endangered Plants to Changes in Light Environment (광환경조절에 따른 멸종위기식물 섬시호의 생리적 반응)

  • Lee, Kyeong-Cheol;Wang, Myeong-Hyeon;Song, Jae Mo
    • Journal of Bio-Environment Control
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    • v.22 no.2
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    • pp.154-161
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    • 2013
  • This study was conducted to investigate the physiological responses of Bupleurum latissimum, endangered plants by light condition. We investigated photosynthetic parameters, chlorophyll contents and chlorophyll fluorescence under different shading treatments (Shaded 50%, 70%, 90% and non-treated). Results showed that net apparent quantum yield (AQY) and chlorophyll contents were significantly increased with elevating shading level. However, light compensation point (LCP) and dark respiration ($R_d$) were shown the opposite trend. Especially, non-treated exhibited photoinhibition such as reduction of chlorophyll contents and maximum photosynthesis rate ($Pn_{max}$) also variation trend of stomatal conductance ($g_s$), and transpiration rate (E) were decreased to prevent water loss. Photosynthetic rate ($P_{Nmax}$) and photochemical efficiency (Fv/Fm) of 90% treatment showed a drastic reduction in July. This implies that photosynthetic activity will be sharply decreased with a long period of low light intensity. The 50% treatment showed relatively higher photosynthetic activity than other treated. This result suggested that growth and physiology of B. latissimum adapted to 50% of full sunlight.

Diaspora and terrorism: An exploration of the relationship between diaspora support and violent terrorist activities in Arab and Africa (디아스포라와 테러활동: 아프리카와 중동지역의 디아스포라의 지원이 폭력적 테러활동에 미치는 영향에 관한 분석연구)

  • Kim, Eun-Young
    • Korean Security Journal
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    • no.39
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    • pp.131-160
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    • 2014
  • The radicalization of diaspora is a new phenomena that have been begun to emerge in the complex picture of terrorism. The existence of diaspora and its supports for violent terrorist activities have made the whole dynamic of terrorism more complicated and unpredictable. Therefore, this study attempts to understand the relationship between diaspora support and violent terrorist activities in the constellation of other significant correlates of violent terrorist activities discussed in the prior studies. In analyses, the author utilized a step wise regrssion analyses with a set of variable drawn from an emphatical data collected in Arab and Africa region. The data used in this study is called as "MAROB"(the Minorities at Risk Organizational Behavior), which is developed by START and Minority at Risk project and contains information terrorist groups in Middle-East and Africa region. Considering the significance of this new emergence of the link between diaspora and violent terrorist activities, and the challenging nature of conducting empirical studies on this topic, this study have great contributions on the development in the field of criminal justice as well as terrorism. Other contributions of this study, policy implications, and suggestions for future studies are further discussed in the discussion.

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Bioconjugation by dual heterobifunctional coupling method: Use of the conjugates for the detection of dopamine (서로 다른 두 작용기를 이용한 결합법에 의한 접합체: 도파민 면역분석법)

  • Ryu, Ji-Eun;Rhee Paeng, In-Sook
    • Analytical Science and Technology
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    • v.23 no.6
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    • pp.537-543
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    • 2010
  • Dopamine (DA) is an important neurotransmitter molecule of catecholamines. Its deficiency could lead to brain disorder such as Parkinson's disease and schizophrenia. Therefore, it is necessary to establish a suitable analytical technique with sensitivity and simplicity. A competitive enzyme-linked immunosorbent assay for DA has been optimized and characterized. Assay sensitivity is controlled by two factors in competitive immunoassay. One is a nature and concentration of competitor, and the other is those of binder, antibody. Thus, optimization was performed: BSA-DA conjugate and antibody-avidin conjugate were prepared by dual heterobifunctional coupling method using SATA and SMCC. Assay condition was optimized with $6.66\;{\mu}gmL^{-1}$ of BSA-DA and $4.17{\times}10^{-10}\;M$ of antibody-avidin conjugate. A dose-response curve was constructed, and a limit of detection and a dynamic range for DA were accomplished to $2.3{\times}10^{-2}\;{\mu}g\;mL^{-1}$ and four orders of magnitude ($1.0{\times}10^{-7}\;M$ to $1.0{\times}10^{-3}\;M$), respectively. Calibration curve was constructed on dynamic range and least-squares regression of this data gave the following relationship: absorbance = -0.1098 log[DA]+0.0353 ($R^2$ = 0.9956).

The variational characteristics of Water Quality and Chlorophyll a Concentration in Kogum-sudo, Southern Part of Korean Peninsula (거금수도 양식어장의 해양환경 특성 2. 수질과 엽록소 양의 변동특성)

  • 윤양호;박종식;고남표
    • Journal of Aquaculture
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    • v.13 no.1
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    • pp.87-99
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    • 2000
  • Field survey on the variational characteristics of water quality and chlorophyll a concentraion were carried out at the 25 stations for four seasons in Kogum-sudo(Straits) southern coast of Korean Peninsula from Feburuary to October in 1993. We made an analysis on biological factor as chlorophyll a concentraion as well as physicio-chemical factors such as water temperature salinity sigma-t transparency dissolved oxygen(DO) chemical oxygen demand(COD) nutrients (ammonia, nitrite, nitrate, phosphate, and silicate) N/P ratio and suspended solid(SS). The waters in the Kogum-sudo were not stratified due to the tidal mixing. And the high productivity in photic layer were supported by high nutrients concentration from bottom waters. The high concen-trations of suspended solid in straits had a bad influence upon marine biology of nature and cultivations. In Kogum-sudo had a sufficient nutrients for primary productivity during a year. Especially phosphate and inorganic nitrogen were high the other side silicate was very low. The source of nutrients supply depend on rather mineralization of organic matters and input of seawater from outside than input of freshwaters from lands. Phytoplankton biomass as measured by chlorphyll a concentratiion was very high all the year round and it was controlled by the combination o f several environmental factors especially of phosphate in summer and dissolved nitrogen in other seasons.

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The New Structure of Police Governance and Its Impact on Police Service Delivery in the UK (치안 거버넌스의 새로운 구조와 경찰 서비스 제공에 미치는 영향: 영국을 중심으로)

  • Loveday, Barry;Jung, Jeyong
    • Korean Security Journal
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    • no.55
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    • pp.169-192
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    • 2018
  • This article assesses the recent police reform strategy in England and Wales with the Police Reform and Social Responsibility Act 2011. Police and Crime Commissioners have a responsibility not just for the police force but also for reducing crime in their area of responsibility. This ensures that their remit runs much more widely than their predecessor body, the police authority. The article goes on to evaluate the nature and extent of crime by making immediate use of survey of local police commanders. The surveys showed that police commands were swamped with minor crime and anti-social offences. The arrival of Police and Crime Commissioners has meant that now police priorities can be more closely aligned to those of the public and where anti-social behaviour is now recognised as impacting on the lives of many residents more significantly than criminal activity. The article highlights the changes introduced by government following the Winsor Review to police pay, pensions and conditions of service. It reflects on the impact of this on both police morale and professional motivation. It suggests that current government policy is now haemorrhaging the police service as increasing numbers of experienced officers are leaving the police service which could ultimately undermine its long-term resilience as a strategic emergency service.

Decolorization of Azo, Triphenylmethane and Heterocyclic Dyes by Irpex zonatus BN2 (송곳니구름버섯(Irpex zonatus) BN2에 의한 아조계, 트리페닐메탄계 및 헤테로싸이클릭계 염료의 탈색)

  • Yoon, Kyung-Ha;Choi, Yang-Soon
    • The Korean Journal of Mycology
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    • v.26 no.1 s.84
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    • pp.8-15
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    • 1998
  • The present research was undertaken to investigate the activity of ligninolytic enzymes and the decolorization capability of some dyes with Irpex zonatus BN2, isolated from nature and identified. For the assay of enzyme activities, the isolate did not produce lignin peroxidase (LiP) and veratryl alcohol oxidase (VAO), but laccase and manganese dependent peroxidase (MnP). While the activity for MnP was low $(61.6\;nmol/mg{\cdot}protein)$, its laccase activity was very high $(1185.9\;nmol/mg{\cdot}protein)$. Moreover, laccase had appeared earlier than MnP. When the isolate was incubated with each dye for 10 days, the decolorization rates of azo dyes, such as orange II, orange G, tropaeolin O and congo red were 98.0%, 97.4%, 99.0% and 95.3%, respectively. In case of heterocyclic dyes, eosin Y, toludine blue, methyl blue and azur B were 97.4 %, 98.7%, 99.9% and 94.0% respectively. Finally the results of triphenylmethane dye such as basic fuchsin, malachite green and crystal violet were 98.5%, 95.7% and 99.4%, respectively. The results suggest that laccase of Irpex zonatus BN2 should be played an important role in the decolorization of the dyes.

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The Geometrical Imagination of the MCU 'Phase 3' Movie (MCU '페이즈3'영화에 나타난 기하학적 상상력)

  • Kim, Young-Seon;Kim, Tae-Soo
    • The Journal of the Korea Contents Association
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    • v.22 no.10
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    • pp.132-142
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    • 2022
  • The purpose of this study is to interpret the MCU's universal worldview from the perspective of geometry and to storytell narrative elements with mathematical imagination. For storytelling, data from the Phase 3 series aired from 2016 to 2019 was used. The Phase 3 series stimulates the imagination of the public with the sense of reality shown in the narrative and images based on geometrical theory and various predictions about future technology. Imagination is the driving force for diverse and original thinking about the unexperienced, and the ability to find order in chaos and create new perceptions of matter. The power of imagination is very necessary not only in artistic activities, but also in the scientific field where logic and rationality are important. Bachelard's imagination aims for art, the primitive realm of human beings, and contains sincerity and passion for the wonders of nature and all things. By exploring the MCU's worldview and superhero narrative through geometrical logic and imagination-driven imagery, you can understand the cosmic messages and laws in the film. From a convergence point of view of art and science, various and original techniques based on mathematics and scientific imagination used in MCU video production will help to improve the quality of video analysis.

International Study and Transformational Learning: What Covid-19 Has Taught Us

  • Rodgers, Steve
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.1221-1221
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    • 2022
  • Studying abroad in and of itself should be a unique and transformational learning experience for university students. Too often, "study abroad" is a code word for "faculty vacation" or "easy credit hours". For an international learning experience to be truly transformational it must offer an intense and directed program that maximizes the time the student spends in the accumulation of information that is new or different from what the student has "learned" previously. "Study abroad" may be a misnomer because it is not only about studying in another country or culture, that is, taking courses that usually have an attendance time of a few hours a week, but it is also about living in another country which becomes a 24/7 learning experience. Providing these programs during the Covid-19 pandemic has been a keen opportunity for institutional learning. When this immersion in foreign culture is combined with academic rigor applied to a student's chosen field of study the growth can be exponential. So, what is the relationship between academic and personal growth? The National Association for Study Abroad has found that "students who have studied abroad are better able to work with people from other countries, understand the complexity of global issues, and have greater intercultural learning. One study found that students returned from their study abroad experiences more tolerant and less fearful of other countries, but with a greater sense of nationalism-a phenomenon they called 'enlightened nationalism'." It is often said that "you only really learn to appreciate things that are important to you when they are gone, when you miss them." The international learning environment can provide this opportunity. The restrictions on various societies in the past two years due to the international Covid pandemic have provided existing study abroad programs with a true testing ground for the validity of their programs. At the end of the day, American colleges and universities are not helpless in the face of these developments. A lot depends on how a university positions itself for a future based on the uncertainties of the past. As Winston Churchill was working to form the United Nations after WWII, he famously said, "Never let a good crisis go to waste". In another context, Churchill's insight on human nature can also be applied to the coming semesters and years as studying abroad rebounds. What new strategies will be developed and maintained? Institutional commitment without fear will be necessary to assure that "studying abroad" will continue to develop as a truly unique and transformational learning experience.

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YouTube Video Content Analysis: Focusing on Korean Dance Videos (유튜브(YouTube) 영상 콘텐츠 분석: 국내 무용 영상을 중심으로)

  • Suejung Chae;Jihae Suh
    • Journal of Intelligence and Information Systems
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    • v.29 no.4
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    • pp.1-13
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    • 2023
  • The widespread adoption of smartphones and advancements in internet technology have notably shifted content consumption habits toward video. This research aims to dissect the nature of videos posted on YouTube, the global video-sharing platform, to understand the characteristics of both produced and preferred content. For this study, dance was chosen as a specific subject from a variety of video categories. Data on YouTube videos associated with the term "dance" was compiled over three years, from 2019 to 2021. The investigation revealed a clear distinction between the types of dance videos frequently uploaded to YouTube and those that receive a high number of views. The empirical analysis of this study indicates a viewer preference for vlogs that provide insights into the daily lives of dance students, as well as for purpose-driven videos, such as those highlighting dance exam preparations or school dance events. Notably, the vlogs that attract the most attention are typically created by dance students at the college or secondary school level, rather than by professionals. Although the study was focused on dance, its methodologies can be applied to different subjects. These insights are expected to contribute to the development of a recommendation system that aids content creators in effectively targeting their productions.