• 제목/요약/키워드: DrDoS

검색결과 53건 처리시간 0.026초

Mieko Han의 한국어 음성학 연구 (Mieko Han and her Works on Korean Phonetics)

  • 고도흥
    • 음성과학
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    • 제1권
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    • pp.213-223
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    • 1997
  • This paper deals with a general review of Mieko S. Han, who made a significant contribution to the studies of Korean phonetics during the 1960' s and early 1970' s. As both a single and joint author, Dr. Han published important papers in both quantity and quality, which have been cited among Korean phoneticians until today. Before Dr. M. Han' s work, professor of USC in the department of East Asian Languages & Cultures, there were only a few phonetics-related publications in Korea, most of which are papers or books based on non-experimental traditional approach. It is known that there was coexistence between traditionalism and structuralism in the field of Korean linguistics. It was, however, fortunate that we had two important phoneticians (M. Han and Chin-W Kim) abroad at that time. Mieko Han' s concern was to investigate experimental characteristics of the system of Korean vowels and consonants using a Spectrograph, which was the single most important tool for analysing phonetic data at that time. Dr. Han conducted her experimental studies on Korean phonetics, mostly funded by the Office of Naval Research, in terms of duration, fundamental frequency, Voice Onset Time (VOT), intensity, and so on. This paper aims to re-appreciate Dr. Han's specific contribution to the study of Korean phonetics since she played an important role as a pioneer of early Korean phonetics. Further, it is highly recommended that Dr. Han's works can be extremely useful for a graduate student, who seriously would like to specialize in Korean phonetics in the first step.

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기업의 Business Continuity를 위한 위기관리시스템 개발에 관한 연구;DR. PEAS의 사례연구 (Implementing Crisis Management System;A Case of DR. PEAS)

  • 이영재;김도연
    • 한국IT서비스학회:학술대회논문집
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    • 한국IT서비스학회 2002년도 추계학술대회
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    • pp.459-466
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    • 2002
  • 위기관리의 목적은 각종 재해 ${\cdot}$ 재난으로 인한 비상사태 발생시 기업의 업무를 지속하고, 신속하게 피해 업무를 복구하는데 있다. 이러한 위기관리의 목적 자체는 언제 어디서나 변함이 없지만, 그 구성 내용과 운영 방안은 시대와 장소에 따라 업무 환경에 알맞도록 적절하게 구성되어야 한다. 따라서 본 논문에서는 한국 기업 환경에 적합한 Business Continuity를 위한 위기관리시스템 개발 모델을 DR. PEAS(Disaster Recovery Plan & Execution Automation System)의 사례를 통하여 제시하고자 한다.

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A pioneer scheme in the detection and defense of DrDoS attack involving spoofed flooding packets

  • Kavisankar, L.;Chellappan, C.;Sivasankar, P.;Karthi, Ashwin;Srinivas, Avireddy
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권5호
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    • pp.1726-1743
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    • 2014
  • DDoS (Distributed Denial of Service) has been a continuous threat to the cyber world with the growth in cyber technology. This technical evolution has given rise to a number of ultra-sophisticated ways for the attackers to perform their DDoS attack. In general, the attackers who generate the denial of service, use the vulnerabilities of the TCP. Some of the vulnerabilities like SYN (synchronization) flooding, and IP spoofing are used by the attacker to create these Distributed Reflected Denial of Service (DrDoS) attacks. An attacker, with the assistance of IP spoofing creates a number of attack packets, which reflects the flooded packets to an attacker's intended victim system, known as the primary target. The proposed scheme, Efficient Spoofed Flooding Defense (ESFD) provides two level checks which, consist of probing and non-repudiation, before allocating a service to the clients. The probing is used to determine the availability of the requested client. Non-repudiation is taken care of by the timestamp enabled in the packet, which is our major contribution. The real time experimental results showed the efficiency of our proposed ESFD scheme, by increasing the performance of the CPU up to 40%, the memory up to 52% and the network bandwidth up to 67%. This proves the fact that the proposed ESFD scheme is fast and efficient, negating the impact on the network, victim and primary target.

김정호의 『청구도』 제작 과정과 지도적 특징에 관한 연구 (A Study on Jeongho Kim′s Cheonggudo)

  • 이기봉
    • 대한지리학회지
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    • 제39권3호
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    • pp.473-493
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    • 2004
  • 김정호는 19세기를 살아간 인물 중에서 지도와 지지에 대해 가장 광범위한 자료를 수집하고 검토한 인물이다. 그는 이러한 검토의 과정에서 그 이전까지 존재하던 지도의 장단점을 체계적으로 연구하여 정리할 수 있었다. 그리고 그러한 연구 성과를 바탕으로 $\boxDr$청구도$\boxUl$라는 뛰어난 지도책을 만들어낼 수 있었다. $\boxDr$청구도$\boxUl$는 내용적으로 보았을 때 김정호가 검토한 모든 지도가 아니라 특정한 지도 계통을 중요한 저본으로 삼고 있다. 그것이 바로 정조 때 만들어진 전국 군현지도책인 $\boxDr$해동여지도$\boxUl$이다 또한 $\boxDr$해동여지도$\boxUl$ 자체도 새롭게 제작된 것이 아니라 영조 때 신경준의 주도에 의해 제작된 것으로 추정되는 $\boxDr$조선지도$\boxUl$를 약간만 바꾸어 놓은 것이다. 따라서 김정호의 $\boxDr$청구도$\boxUl$는 조선 후기 내내 이루어진 정확한 지도 제작의 결과물을 새로운 형식과 내용을 가미하여 탄생된 것이라고 볼 수 있다. $\boxDr$청구도$\boxUl$에는 지도의 제작과 이용에 관한 일반적인 내용뿐만 아니라 지도의 교정에 관한 방법도 서술되어 있다. 이것은 $\boxDr$청구도$\boxUl$를 개정하려는 김정호 자신의 의지를 표현한 것이다.

BESS의 DR(Demand Response) 적용 시 수용가의 투자비 최소화를 위한 적정용량산출방법 (A Study on the Battery Storage Volume Optimization in case of DR Participation for the Minimization of the Customer's Investment Cost)

  • 양승권;김대영
    • 조명전기설비학회논문지
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    • 제27권1호
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    • pp.17-23
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    • 2013
  • The BESS(Battery Energy Storage System) is an useful device for load leveling, but the high cost, installation space and safety issues are the main barriers for supplying it widely. The important factor in supplying BESS to customers successfully is the payback period. As most of the H/W cost factors are uncontrollable, the optimization of storage volume can be useful factor in improving payback period. In order to obtain optimized BESS volume, the load factor, demand ratio, peak shaving ratio, electric rates and benefits from DR participation of customer should be analyzed. In this paper, we could verify the peak cutting capability and cost effectiveness under the some proposed conditions and changing value of PCS and battery based on the customers data after volume optimization process was applied, and we can identified the saturation point of load factor and shortening of customer's payback period.

갑상선 질환들에서 여포세포의 HLA-DR발현 (Thyrocyte HLA-DR Expression in Variety of Thyroid Diseases)

  • 장은숙;손수상;조승제;김인호;김상표;강중신
    • 대한두경부종양학회지
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    • 제13권1호
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    • pp.16-23
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    • 1997
  • Although normal thyroid epithelial cells do not constitutively express HLA-DR antigen, their expression in wide spread within thyroid glands obtained from the human with autoimmune thyroid disease and with many neoplastic thyroids. We have, therefore, studied immunohistochemically with regard to the expression of HLA-DR antigen of thyroidectomy specimens from 50 patients of various thyroid diseases with use of paraffin-embedded tissue. One or two sections from each case were stained with commercially available mouse monoclonal antibody for class II HLA-DR antigen(HLA-DR/Alpha, DAKO) and examined by semiquantitative counting system for thyrocytes, neoplastic thyrocytes and other cells expressing HLA-DR antigen. All patients with lymphocytic thyroiditis(2/2) and diffuse hyperplasia(Graves' disease)(5/5), most patients with Hashimoto's disease(9/ll) expressed HLA-DR antigens in thyrocyte with abundant HLA-DR expressing lymphocytic infiltrates with lymph follicle formation in its vicinity or adjacent to the lesion. Most patients with papillary carcinoma(9/1l) had HLA-DR antigen detected in malignant thyrocytes ; while follicular carcinoma(0/3) and follicular adenoma(0/5) did not have detactable HLA-DR immunoreactivity. Adenomatous goiter(3/7) had HLA-DR antigen detected focally in lesser than half cases. Conversely, in four papillary carcinomas and three adenomatous goiters, HLA-DR expression of thyrocytes was found in the absence of HLA-DR expressing lymphoid infiltrates. In such cases therefore other factors more than thyroid autoimmunity must be causative for HLA-DR immunoreactivity. The results of this study indicate as follows. 1) The expression of HLA-DR on thyrocytes involved in autoimmune reactions appeared to be secondary to cytokine release from associated lymphocytic infiltrates. 2) Thyrocytes in thyroid lesions with equal degrees of lymphocytic infiltration without HLA­DR expression exhibited no HLA-DR immunoreactivity. 3) In neoplastic thyrocytes, most papillary carcinoma(9/11) exhibited detactable HLA-DR expression, while follicular carcinoma/adenoma(0/3/0/5) exhibited no detactable HLA-DR immunoreactivity which suggest the existence of divergent mechanisms inducing and modulating HLA-DR expression of different types of neoplastic thyrocytes.

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Does Gender Influence Investment Choice? A Psychosomatic Study of GCC Entrepreneurs

  • KHAN, Mohammed Abdul Imran;JAMIL, Syed Ahsan;KHAN, Shahebaz Sarfaraz;ALI, Meer Mazhar
    • The Journal of Asian Finance, Economics and Business
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    • 제9권4호
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    • pp.299-306
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    • 2022
  • Entrepreneurs with behavioral finance biases are more likely to make irrational or financially detrimental decisions. Understanding financial behavior biases can assist in making sound financial decisions. Behavioral finance is a new topic that can assist researchers in better understanding investor behavior and preferences while purchasing and selling stocks. Using measures such as independent t-tests and average Likert five-point scale scores, this study seeks to determine how entrepreneurs make investment decisions and whether gender makes a difference. The study is empirical, and data from 1000 entrepreneurs were collected through convenience sampling. The study's main findings show that there are numerous factors to consider while investing in stocks, including family planning, children's education, investment security, and recurring income. Both men and women attempt to invest in many asset classes, but certain investments are extremely risky, while others are low risk. As a result, investors should assess risk based on their age and experience rather than their gender; this indicates that an investment in venture capital has nothing to do with gender but everything to do with the investor's age.

IP Spoofing을 이용한 분산 반사 서비스 거부 공격의 보안 위협과 대응 실태 연구 (A Study of security threats and response of Distribute Reflection Denial of Service Attack using IP spoofing)

  • 홍윤석;한우영
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2022년도 추계학술대회
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    • pp.143-145
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    • 2022
  • 전 세계적인 인터넷의 보급으로 인터넷과 연결된 기기들이 점차 늘어나고 있다. 이에 더불어 DNS, NTP, CLDAP 와 같이 응용 프로토콜의 취약점을 이용하여, 공격자가 피해자인 것처럼 아이피를 속여, 다량의 응답을 악의적으로 요청하는 공격인 분산 반사 서비스 거부 공격(DRDoS)이 급격하게 늘어나는 추세이다. ISP 들이 IP Spoofing에 대한 적절한 대비책을 수립하지 않으면 분산 반사 서비스 공격의 보안 위협은 사라지기 어려울 것으로 사료된다. 따라서 본 논문에서는 IP Spoofing에 기반한 분산 반사 서비스 공격의 보안 위협과 대응 실태에 관해 기술한다.

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Physical Origin of the Planar Alignment of Satellite Galaxies

  • Seo, Chanoul;Paudel, Sanjaya;Yoon, Suk-Jin
    • 천문학회보
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    • 제45권1호
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    • pp.33.3-34
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    • 2020
  • The Milky Way (MW) and other systems including M31 and Cen A have flattened structures of their satellites (Disk of Satellites, DoS). Such structures are rare in simulations under the ΛCDM paradigm. DoS is known to depend mainly on 1) the alignment of satellite orbits and 2) the degree of central concentration of satellites. In this work, we examine quantitatively how these two parameters affect the flatness of a system. We find that the MW-like DoS is rare in IllustrisTNG100 simulation because its two parameters are out of the 1-s range and furthermore the MW has a structure more flattened than the other systems having similar parameters. Besides, we propose a new criterion for the MW-like systems superseding the conventional ones such as major-minor axis ratio of the MW's DoS with a value of 0.183. Each satellite system has a specific orbital combination and thus has a particular distribution of its parameters (and thus flatness). The median of the distribution is set as the representative value of each system. And the representative value of the MW can be used as a new criterion for classifying the MW-like DoS. We reconstruct the orbital combination of the observed MW satellites using GAIA DR2 data and find the systems in the simulation that have representative values similar to the new criterion from the reconstructed MW system. This allows us a new interpretation on the rarity of MW-like DoS in cosmological simulations.

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Prevention of UV-induced Skin Damage by Activation of Tumor Suppressor Genes p53 and $p14^{ARF}$

  • Petersen, R.;John, S.;Lueder, M.;Borchert, S.
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.338-351
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    • 2003
  • UV radiation is the most dangerous stress factor among permanent environmental impacts on human skin. Consequences of UV exposure are aberrant tissue architecture, alterations in skin cells including functional changes. Nowadays new kinds of outdoor leisure-time activities and changing environmental conditions make the question of sun protection more important than ever. It is necessary to recognize that self-confident consumers do not consider to change their way of life, they demand modern solutions on the basis of new scientific developments. In the past one fundamental principle of cosmetics was the use of physical and organic filter systems against damaging UV-rays. Today new research results demonstrate that natural protecting cell mechanisms can be activated. Suitable biological actives strongly support the protection function not from the surface but from the inside of the cell. A soy seed preparation (SSP) was proven to stimulate natural skin protective functions. The major functions are an increased energy level and the prevention of DNA damage. These functions can I be defined as biological UV protection. The tumor suppressor protein p53 plays a key role in the regulation of DNA repair. p53 must be transferred into the phosphorylated form to work as transcription factor for genes which are regulating the cell cycle or organizing DNA repair. A pretreatment with SSP increases the phosphorylation rate of p53 of chronically UV-irradiated human keratinocytes significantly. According to the same test procedure SSP induces a dramatic increase in the expression of the tumor suppressor protein p14$^{ARF}$ that is supporting the p53 activity by blocking the antagonist of p53, the oncoprotein Mdm2. Mdm2, a ubiquitin E3-ligase, downregulates p53 and at the same time it prevents phosphorylation of p53. The positive influence of the tumor suppressor proteins explains the stimulation of DNA repair and prevention of sunburn cell formation by SSP, which was proven in cell culture experiments. In vivo the increased skin tolerance against UV irradiation by SSP could be confirmed too. We have assumed, that an increased repair potential provides full cell functionality.y.

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