• Title/Summary/Keyword: Power law 관계

Search Result 133, Processing Time 0.028 seconds

Determination of Abrasion Rate of SBR Rubber Compounds using a Knife-blade Abrader (칼날형 마모시험기를 이용한 SBR 배합고무의 마모속도 결정)

  • Kim, Dong-Hui;Kaang, Shinyoung
    • Elastomers and Composites
    • /
    • v.49 no.2
    • /
    • pp.149-154
    • /
    • 2014
  • Friction and abrasion behaviors were investigated for SBR rubber compounds reinforced by silica and carbon black. Knife-blade abrader, newly designed based on tearing energy theory, was utilized in order to evaluate the effect of frictional work on the wear rate of the rubber compounds. It was found that the power law relation between frictional work and wear rate worked, in which as the wear rate was increased as frictional work increased. The wear rate could be determined successfully using the knife-blade abrader in which a moving distance of the knife blade in the process of wearing was measured continuously, instead of intermittent measurements of weight loss by wear during experiment.

The Study of UCC and 'Power law of Participation' for Web 2.0 Environment (웹 2.0 환경에서 UCC와 참여의 멱함수 법칙에 관한 소고)

  • Kang, Jang-Mook;Moon, Song-Chel
    • 한국IT서비스학회:학술대회논문집
    • /
    • 2007.11a
    • /
    • pp.131-135
    • /
    • 2007
  • 참여의 멱함수 이론은 UCC를 생산, 배포, 소비, 재생산하는 과정에 참여하는 사용자들을 분석하는 유용한 도구이다. 참여의 멱함수 이론을 통해 무리는 집합적 지성과 집단 지성을 구분하고 참여의 형태를 세분화하며 참여자간의 관계 분석할 수 있다. 즉 다양한 기술, 사회, 정치 현상들에 배경 정보가 되어 영향력을 행사하는 UCC는 어떤 이유로 제작되고 어떤 형태로 나누어지며 생산한 사람들 간의 관계 또는 생산자와 생산자 고리고 생산자와 소비자 간의 관계를 설명할 때 설득력들 높인다. UCC가 웹 2.0의 어떤 기술 속에 생산되고 배포되고 소비되는지에 대한 플랫폼의 설계에도 멱함수 법칙은 도움을 주는 도구이다.

  • PDF

Relationship Between Tweet Frequency and User Velocity on Twitter (트위터에서 트윗 주기와 사용자 속도 사이 관계)

  • Jeon, So-Young;Lee, Al-Chan;Seo, Go-Eun;Shin, Won-Yong
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.19 no.6
    • /
    • pp.1380-1386
    • /
    • 2015
  • Recently, the importance of users' geographic location information has been highlighted with a rapid increase of online social network services. In this paper, by utilizing geo-tagged tweets that provides high-precision location information of users, we first identify both Twitter users' exact location and the corresponding timestamp when the tweet was sent. Then, we analyze a relationship between the tweet frequency and the average user velocity. Specifically, we introduce a tweet-frequency computing algorithm, and show analysis results by country and by city. As a main result, it is shown that the tweet frequency according to user velocity follows a power-law distribution (i.e., Zipf' distribution or a Pareto distribution). In addition, by performing a comparison between the United States and Japan, one can see that the exponent of the distribution in Japan is smaller than that in the United States.

Time Series Modelling of Air Quality in Korea: Long Range Dependence or Changes in Mean? (한국의 미세먼지 시계열 분석: 장기종속 시계열 혹은 비정상 평균변화모형?)

  • Baek, Changryong
    • The Korean Journal of Applied Statistics
    • /
    • v.26 no.6
    • /
    • pp.987-998
    • /
    • 2013
  • This paper considers the statistical characteristics on the air quality (PM10) of Korea collected hourly in 2011. PM10 in Korea exhibits very strong correlations even for higher lags, namely, long range dependence. It is power-law tailed in marginal distribution, and generalized Pareto distribution successfully captures the thicker tail than log-normal distribution. However, slowly decaying autocorrelations may confuse practitioners since a non-stationary model (such as changes in mean) can produce spurious long term correlations for finite samples. We conduct a statistical testing procedure to distinguish two models and argue that the high persistency can be explained by non-stationary changes in mean model rather than long range dependent time series models.

Error analysis on the Offshore Wind Speed Estimation using HeMOSU-1 Data (HeMOSU-1호 관측 자료를 이용한 해상풍속 산정오차 분석)

  • Ko, Dong Hui;Jeong, Shin Taek;Cho, Hongyeon;Kim, Ji Young;Kang, Keum Seok
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.24 no.5
    • /
    • pp.326-332
    • /
    • 2012
  • In this paper, error analyses on the calculation of offshore wind speed have been conducted using HeMOSU-1 data to develop offshore wind energy in Yeonggwang sea of Korea and onshore observed wind data in Buan, Gochang and Yeonggwang for 2011. Offshore wind speed data at 98.69 m height above M.S.L is estimated using relational expression induced by linear regression analysis between onshore and offshore wind data. In addition, estimated offshore wind speed data is set at 87.65 m above M.S.L using power law wind profile model with power law exponent(0.115) and its results are compared with the observed data. As a result, the spatial adjustment error are 1.6~2.2 m/s and the altitude adjustment error is approximately 0.1 m/s. This study shows that the altitude adjustment error is about 5% of the spatial adjustment error. Thus, long term observed data are needed when offshore wind speed was estimated by onshore wind speed data. because the conversion of onshore wind data lead to large error.

A Study on the Needs to Improve the Regulations and the Design Features of Fire Protection for UAE Nuclear Power Plants (UAE원전 화재방호계통 설계특성과 화재방호규제 개선 필요성 연구)

  • Ma, Jin-Soo;Lee, Eui-Pyeong
    • Fire Science and Engineering
    • /
    • v.25 no.5
    • /
    • pp.54-61
    • /
    • 2011
  • The study is to analysis of fire protection regulations for the nuclear power plants (NPP) in the United States, Japan, the UAE (United Arab Emirates), and Korea with the intention of exporting NPP to the UAE. Fire protection regulations for NPP for these countries permit the fire protection design and facilities in accordance with the evaluation of the potential fire hazards. However, in Korea, the NPP is a part of power generation facilities in Korea fire protection law, and the atomic energy act classifies them as the reactor and related nuclear facilities. The fire protection law and atomic energy act are different to the criteria for the fire protection of NPP. To maintain the leading position as a nuclear exporting country, the performance-based fire hazard analysis should be reasonably incorporated in the design of the fire protection system. It was suggested that the integrated requirements of the fire protection for NPP should be incorporated to the construction article for the fire protection facilities specified in paragraph 2 of Act II, being classified into the special objects to be protected against fire, which requires a performance-based design in order to incorporate the specific requirements for NPP.

A Speculation on The Independence of Police Investigational Right In Terms of Public Law (경찰수사권독립 논의의 공법적 검토)

  • Oh Tae-Kon
    • The Journal of the Korea Contents Association
    • /
    • v.5 no.4
    • /
    • pp.54-61
    • /
    • 2005
  • Sixty years have passed since the police system was established in Korea. So far, there have been consistent discussions on independence of police investigational rights. Political powers have mentioned its independence as one of their public commitments and specifically, it has been a big issue in respect to establishment of the current participation government. The issues involved in investigational rights were derived from the regulations as follows: 'Prosecutors shall manage investigation(No. 195. the Criminal Procedure Act) and 'The police shall be guided by prosecutors in respect to investigation'(No. 195. the Criminal Procedure Act). President No Mu-hyun proposed he would take care of the issues involved in investigational rights at an interview. This study speculates investigational right systems of countries that follow continental law system and English law system and more valid investigational right system based on the guaranty of human rights and the principle of power division to find reasonable suggestions on independence issue.

  • PDF

Power-law Distributional Perturbation Analysis of the Topology of Reconstructed Genetic Networks (재구성된 유전자 네트워크의 섭동적(Perturbational) 토폴로지 변형 분석)

  • 이상근;장병탁
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2003.10b
    • /
    • pp.754-756
    • /
    • 2003
  • DNA칩 기술로 얻어지는 대규모 섭동데이터(perturbation data)는 생물학적시스템(biological system)의 유전자네트워크(genetic network)를 재구성(reverse-engineering)하는데 있어 유용하다. 그러나 기존의 연구는 유전자 조절 관계의 규명이나 혹은 데이터를 설명하는 최적의 모델을 찾는 방향에만 관심을 두고 있고. 실험적인 한계로 인한 DNA칩 데이터의 오류가 재구성된 네트워크의 구조에 미치는 영향에 대해서는 중요하게 다루고 있지 않다. 본 논문에서는 유전자 네트워크의 멱함수(power-low) 분포 구조를 이용하여, 섭동 데이터의 오류가 재구성된 네트워크의 토폴로지(topology)에 미치는 영향을 분석하였다. 가상의 네트워크에 대한 데이터를 사용하여 실험한 결과, 데이터의 오류 정도에 따른 네트워크 토폴로지의 변형 양상을 관측할 수 있었다.

  • PDF

Intelligence and Virtue for Happy Democratic Citizens (행복한 민주시민의 지성과 덕성)

  • Kim, Dong-il
    • Journal of Korean Philosophical Society
    • /
    • v.146
    • /
    • pp.25-48
    • /
    • 2018
  • Starting from common sense that happiness is a state where needs are satisfied, this paper suggests the intelligence and the virtues for democratic citizens. The fact that human beings exist, relate to each other, and undertake activities which can become of moral worth when joined by autonomy, equality, and responsibility, respectively, is explained. It is also discussed that happy citizens should be able to exist autonomously in the face of political power, make an equal relationship with political power and fellow citizens, and undertake responsible activities. Lastly, it is suggested that happy citizens should be able to understand the plurality of value-contents, the similarity of value-forms, and the possibility of value-realization, and then be equipped with self-respect, mutual respect, and law-respect.

Review of Consultation Requirements Under Military Air Base Law (군용 항공기지법상의 협의제도에 대한 법적고찰)

  • Lee, Kwan-Hyoung
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.18
    • /
    • pp.385-444
    • /
    • 2003
  • Current Military Airbase Law, in an effort to promote safety of military aircraft and security of military airbase, requires an administrative agency or its empowered branch to consult with the Secretary of Defense or the commander of the airbase before they issue a certain administrative approval or decision related to the installation. Although this consultation process purports itself in simplifying what can be an protracted administrative procedure, and in unifying objectives of the military and the administrative services, such procedural requirement is vulnerable inevitability of various legal problems whenever there is a conflict of interests among civil, military, government services. Nor is there sufficient studies done by academian in the area of bureaucratic issues of administrative resolution, and certainly not in the area of the military consultation procedure. This article, with such reality in mind attempts to constructively examine 1) when a consultation application is submitted, whether the discretionary power of the commander of the affected airbase is acknowledged at the outset; 2) if the content of the consultation is deemed unlawful, whether a civilian can institute an administrative lawsuit against it; 3) problems about the subject matters of the consultation requirement within the framework of military airbase law; 4) whether the issuing administrative agency must abide by and issue approval or decision in accordance with the opinion proposed by the said commander; 5) the legal problems of the remedial measure such as an order of removal, appellate review, notion to challenge authority, and etc. in cases such as administrative agency ignoring the commanders proposal or issuing final approval or decision that is inconsistent with what was consulted and agreed upon between both parties.

  • PDF