• 제목/요약/키워드: round size

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DDoS attacks prevention in cloud computing through Transport Control protocol TCP using Round-Trip-Time RTT

  • Alibrahim, Thikra S;Hendaoui, Saloua
    • International Journal of Computer Science & Network Security
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    • 제22권1호
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    • pp.276-282
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    • 2022
  • One of the most essential foundations upon which big institutions rely in delivering cloud computing and hosting services, as well as other kinds of multiple digital services, is the security of infrastructures for digital and information services throughout the world. Distributed denial-of-service (DDoS) assaults are one of the most common types of threats to networks and data centers. Denial of service attacks of all types operates on the premise of flooding the target with a massive volume of requests and data until it reaches a size bigger than the target's energy, at which point it collapses or goes out of service. where it takes advantage of a flaw in the Transport Control Protocol's transmitting and receiving (3-way Handshake) (TCP). The current study's major focus is on an architecture that stops DDoS attacks assaults by producing code for DDoS attacks using a cloud controller and calculating Round-Tripe Time (RTT).

제한된 메모리의 모바일 수신자를 고려한 수신자 기반 TCP 흐름 제어 (A Receiver-driven TCP Flow Control for Memory Constrained Mobile Receiver)

  • 이종민;차호정
    • 한국정보과학회논문지:정보통신
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    • 제31권1호
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    • pp.91-100
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    • 2004
  • 본 논문은 제한된 메모리를 가진 모바일 수신자를 고려한 무선 상태 적응적인 TCP 흐름 제어방법을 제안한다. 수신자에 의한 TCP 흐름 제어는 수신자에서 Advertised 윈도우를 조정함으로써 수행된다 제안된 방법은 수신자가 사용 가능한 무선 대역폭과 패킷 전송 지연 시간을 동적으로 측정하며, 측정된 정보를 기반으로 Advertised 윈도우를 적절히 조정한다. 무선 상태를 반영한 Advertised 윈도우의 조정으로 인해 송신자의 전송 성능 향상과 종단간 패킷 전송 지연 시간을 줄일 수 있다. 제안된 방법은 수신자에서의 TCP 변경만으로 구현될 수 있고 송신자나 중간 라우터의 변경을 필요로 하지 않는다. 제안된 방법의 구현과 CDMA2000 1x 환경에서의 실험을 통해 수신자 버퍼 크기가 2896 Bytes일 경우, 흐름 제어를 사용할 때가 기존 방식보다 전송률을 약 5배 향상시킬 수 있음을 보인다. 또한, 수신자 버퍼 크기가 64 KBytes일 경우 흐름 제어를 사용할 때가 기존 방식보다 때보다 종단간 패킷 왕복 시간은 반 이하로 줄일 수 있음을 보인다.

닭의 정자선(精子腺) 기능(機能) 향상(向上)을 위한 연구(硏究) 1. 조직화학적(組織化學的) 및 전자현미경적(電子顯微鏡的) 관찰(觀察) (Study on functional elevations of sperm-host glands in domestic hens 1. Histochemical and electron microscopical observations)

  • 곽수동;우호춘;최상용
    • 대한수의학회지
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    • 제31권1호
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    • pp.1-10
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    • 1991
  • The present investigation was focussed on histochemical and electron microscopical observations of utero-vaginal(U-V) glands in U-V junctions of domestic hens. In histochemical observations, fine granules by PAS technique for mucopolysaccharides and nile blue stain for acidic lipids were slightly stained on the cytoplasm of U-V glandular epithelium. Larger granules by Sudan black B stain for neutral fat and phospholipids and Sudan III stain for neutral fat were heavily stained on the perinuclear region of the U-V gland epithelial cells. These positive materials were heavily stained on the U-V glandular epithelium of lowfecundity hens and non-laying hens. In scanning electron microscopic findings of the U-V junction surface, the orifices of U-V glands are seen as the crater-like invagination. The neck of the U-V gland and the epithelium of U-V iunction were covered by ciliated epithelial cells. Aggregates of spermatozoa are observed often to be on the necks of the U-V gland. These spermatozoa heads are embedded in the glandular tubules and many spermatozoa tails are free on the epithelium of uterine surface. In transmission electron microscopic findings, the epithelial cells of the U-V glandular orifices were ciliated, columnar cells. The apical regions of these cells contained numerous electrondense, round secretory granules of uniformly size. The epithelial cells of the U-V glandular tubule were columnar or pyramid shape with round or oval nuclei. These epithelial cells have numerous microvilli and also contained electron-dense, round secretary granules of uniformly size and electron-lucent vesicles of various size. Spermatozoa are seen as the cross-sections of various regions of heads and tails in glandular tubules. Also spermatozoa arranged longitudinally parallel within the glandular tubules.

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담양 떡갈비 담음새 실태조사 및 개선 방안 (The Actual Condition Investigation and Improvement Plan on Plating Tteokgalbi of the Dam-Yang)

  • 김수인;박연진
    • 동아시아식생활학회지
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    • 제22권3호
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    • pp.323-333
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    • 2012
  • This study aimed at helping to raise the reputation of Tteokgalbi for tourists visiting Damyang by studying the plating of Tteokgalbi. For 15 representative restaurants selling Tteokgalbi, we investigated the balance, blank, and proportions through studying the shape, material, and size of the dishes, and the number, shape, and garnish of one serving size of Teokgalbi. The results of our study suggested that round dishes (7 restaurants) and elliptical dishes (6 restaurants) similar to the shape of Teokgalbi are mainly used. For 13 out of 15 restaurants, the dishes were mainly casting pans in order to serve Tteokgalbi warm. The diameters of round dishes were 230 mm (3 restaurants), 265 mm (2 restaurants), and 300 mm (2 restaurants), and the elliptical dishes mostly had widths of 150 mm and lengths of 240 mm. The color of the dishes was N2-N3, similar to black, and N1, black of pale colors, because the dishes were mainly casting pans. The number of Teokgalbi per serving size was 3 in 12 restaurants. whole sesame was used most (7 restaurants) as a garnish. The results suggested that the color of the dishes and garnish could not imbue much distinction in the color of Tteokgalbi. In other words, Tteokgalbi is now served without consideration of the color, shape, size, or material of Tteokgalbi. The size of Tteokgalbi should be decided with consideration for the size of the dish and the amount of one serving size, and it is necessary to keep studying the process of making and garnish of Tteokgalbi.

삼차원 유한요소 해석에 의한 골내 임프란트의 구조에 관한 연구 (THREE-DIMENSIONAL FINI6E ELEMENT ANALYSIS OF THE ENDOSSEOUS IMPLANT DESIGNS)

  • 현연근;권종진
    • 대한치과보철학회지
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    • 제35권1호
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    • pp.181-210
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    • 1997
  • The stress distribution generated in the surrounding bone was calculated and compared for various geometry of the dental implants by means of the finite element methods. The models were designed to represent the screw type endosseous implants(varing the size, shape, direction of the screw thread and the angle of the body) with supporting bone and the cylinder type endosseous implants(varing the lower portion-Round type, tapered type) with supporting bone. Static mean bite forces were applied 100N vertically and 25N horizontally on the center of the implant and three dimensional finite analysis was undertaken using software ANSYS 5.1 Version. The result demonstrated that different implant shape leads to significant variations in stress distribution in the bone. In the case of variation of the screw size, direction and shape the implant model with normally directional and triangular screw implied lower stress than with upper directional or lower directional and quadrangular screw but among models a different screw size, within a variation of 0.2mm there was no meaningful difference in maximum stress. In the case of variation of angle of body the straight implied lower stress than the tapered. As a result of analysis of cylinder type, the implants with larger radius of curvature of the round form and larger diameter of the tapered form implied lower stress.

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초기 슬롯-카운트 크기에 따른 Gen-2 Q-알고리즘의 성능 분석 (Performance Analysis of Gen-2 Q-Algorithm According to Initial Slot-Count Size)

  • 임인택
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2010년도 추계학술대회
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    • pp.445-446
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    • 2010
  • Gen-2 Q-알고리즘에서는 질의 라운드 동안 사용할 슬롯-카운트 매개변수인 $Q_{fp}$에 대한 초기 값이 정의되어 있지 않다. 이 경우, 만일 초기 $Q_{fp}$ 값이 아주 큰 경우에는 초기 질의 라운드 동안 빈 슬롯이 많이 발생할 수 있고, 반면 초기 $Q_{fp}$ 값이 아주 적은 경우에는 충돌이 많이 발생할 수 있다. 이로 인하여 질의 라운드 동안 최적의 프레임 크기에 수렴하는 속도가 늦어질 수 있으므로 식별 속도 및 효율이 저하되는 문제점이 발생할 것으로 예상된다. 따라서 본 논문에서는 초기 슬롯 카운트의 값이 Gen-2 Q-알고리즘의 성능에 미치는 영향을 분석한다.

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시니어 시프트를 고려한 고령 여성의 체간부 체형 연구 (Torso shape study of older women considering the senior shift)

  • 김아영;어미경
    • 한국의상디자인학회지
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    • 제21권4호
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    • pp.115-126
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    • 2019
  • The purpose of this study is to analyze the characteristics of older women's torso shapes. The data was collected from the 7th Size Korea, which featured 453 women between the ages of 70-85. A factor analysis was performed of 31 indices, including seventeen based on height and length measurements, eight based on circumference measurements, and six based on torso flattening. The torso shape was determined from seven factors: torso flatness ratio, shape of the side upper torso, vertical size of upper torso, silhouette of the torso, silhouette of the bust and abdomen, shape of the hip, and the vertical size of the back of upper torso. The torso shapes of older women were classified into three types based on the results of the factor analysis. Type 1 is called the large rectangle type. They have the lowest degree of forward bend in the torso, the largest vertical and horizontal size, a round body shape, and the upper torso is gently curved. Type 2 is called the inverted triangle type. They also have a round body shape, but the abdominal size is relatively small compared to the size of the bust, and also have an open and drooping bust, and the biggest degree of forward bend in the torso. Type 3 is called the square type. They are characterized by drooping hips, the smallest vertical and horizontal sizes, and the gentlest curve of the torso.

청년들의 얼굴형태와 안경착용에 관한 연구 (A Study on Face Types and Glasses Wear of Young Peoples)

  • 김혜동;김현정
    • 한국안광학회지
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    • 제12권3호
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    • pp.35-38
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    • 2007
  • 만 20세에서 30세 사이의 남녀 100명을 대상으로 눈 크기를 측정하였고, 얼굴형과 안경착용에 관한 연구를 한 결과 다음과 같은 결론을 얻었다. 1. 전체적인 눈의 가로 크기는 2.4 mm 2명 이하(2%), 2.5-2.9 mm 40명(40%), 3.0-3.5 mm 57명(57%), 3.6 mm 1명(1%)이였다. 2. 전체적인 눈의 세로 크기는 1.1 mm 52명 이하(52%), 1.2-1.4 mm 28명(28%), 1.5-1.7 mm 18명(18%), 1.8 mm 2명 이상(2%)이였다. 3. 전체적인 얼굴형태는 타원형이 29명(29%), 둥근형 24명(24%), 각진형 18명(18%), 세모형 29명(29%)이였다. 4. 남자의 얼굴형태는 타원형이 16명(32%), 둥근형 5명(10%), 각진형 13명(26%), 세모형 16명(32%)이였다. 5. 여자의 얼굴형태는 타원형이 15명(30%), 둥근형 20명(40%), 각진형 6명(12%), 세모형 9명(18%)이였다. 6. 전체적으로 PD에 비해 FPD가 너무 큰 경우 49명(49%), 적당한 크기 25명(25%), PD에 비해 FPD가 너무 작은 경우 26명(26%)이였다. 7. 남자는 PD에 비해 FPD가 너무 큰 경우 14명(28%), 적당한 크기 18명(36%), PD에 비해 FPD가 너무 작은 경우 18명(32%)이였다. 8. 여자는 PD에 비해 FPD가 너무 큰 경우 22명(44%), 적당한 크기 13명(26%), PD에 비해 FPD가 너무 작은 경우 15명(30%)이였다.

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Knitwear의 사이즈 호칭(呼稱)과 기본제품(基本製品)치수에 관(關)한 실태(實態) 조사(調査) (A Study on the Size Designation and Basic Product Size of Women's Knitwear)

  • 김은희;손희순
    • 패션비즈니스
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    • 제4권3호
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    • pp.131-139
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    • 2000
  • The purpose of this study is to provide for the basic data useful to the knitwear size standards for the effective production. For this purpose, knit promotions that product knitwear for 20 age $\sim$ 30 middle age women were sampled to survey their condition of the size designation and basic product size of knitwear, and their directors were surveyed through direct interviews. Data is processed by a computer(SPSS) and analyzed by using frequency, percentage, mean and mode. The results of this study are as follows. 1. Size designation and bodysize of knitwear are not standardized. 2. Knit promotions that don't mark bodysize on the size designation label are not a few. 3. Cardigan's sizes except for a few part are equal to round/pola T-shirt's sizes or are large more than those.

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전통 민도리식 목구조 화통맞춤의 구조적 특성 (A Structural Characteristics of Hwatong-Connections in Traditional Mindori Type of Wood Structures)

  • 유혜란;권기혁
    • 건축역사연구
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    • 제21권3호
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    • pp.7-28
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    • 2012
  • This study is intended to Mindori structure which is general private houses' structural type among traditional types and is a basic study to confirm structural characteristics of Hwatong connection which is general connection type of column-beam-cross beam. It is aimed to analyze how main member, column, such as size, figure, thickness of Sungetuk and Dugeup affect on structure. Following conclusions are drawn. 1. According to connection conditions, models with big coefficient of friction show stable hysteretic behavior until the angle rotation of member reaches 1/60 and models with small coefficient of friction show dramatical increase in load after the angle rotation of member reaches 1/24. After the angle rotation of member reaches 1/30, separation distance of members is identified physically and cracks are not observed. 2. Specimens with big coefficient of friction show similar inner force regardless of column size(except column size 150mm) and models with small coefficient of friction show increasing inner force as the column size increases. Specimens with same sectional area have similar inner force even though the column figures are different. The thickness of Sungetuk and Dugeup doesn't affect inner force greatly, however, when the thickness of Sungetuk is thin, it could lead to failure of structure as it breaks. 3. The bigger the size of column and the coefficient of friction are, the smaller Bending stiffness depreciation ratio is. 4. Energy Dissipation Efficiency differs from the coefficient of friction. When the coefficient of friction is big, square column shows bigger than round one and it is bigger when the thickness of Sungetuk and Dugeup is thicker. When the coefficient of friction is small, round column shows bigger than square one.