• Title/Summary/Keyword: Second-hand

Search Result 2,098, Processing Time 0.026 seconds

Design of Fast Elliptic Curve Crypto module for Mobile Hand Communication

  • Kim, Jung-Tae
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.2
    • /
    • pp.177-181
    • /
    • 2008
  • The more improved the Internet and the information technology, the stronger cryptographic system is required which can satisfy the information security on the platform of personal hand-held devices or smart card system. This paper introduces a case study of designing an elliptic curve cryptographic processor of a high performance that can be suitably used in a wireless communicating device or in an embedded system. To design an efficient cryptographic system, we first analyzed the operation hierarchy of the elliptic curve cryptographic system and then implemented the system by adopting a serial cell multiplier and modified Euclid divider. Simulation result shows that the system was correctly designed and it can compute thousands of operations per a second. The operating frequency used in simulation is about 66MHz and gate counts are approximately 229,284.

A Study on the Expressive Technique of Grunge Look in the Knitwear Fashion of the Last Decade (니트웨어에 나타난 그런지룩의 표현기법에 관한 연구 -′90년대 중반 이후를 중심으로-)

  • 김경인
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.5 no.3
    • /
    • pp.25-36
    • /
    • 2003
  • The purpose of this study is to analyze the expressive technique of grunge look in knitwear fashion. For this study, I have investigated theories of retro and decontructionism trends, and have examined pictures from professional fashion magazines. The results of study on the expressive technique of grunge look reflected on the knitwear fashion were as follows; (1) patchwork technique, which is an outstanding method of recycling, (2) handknitting technique, which came from retro trend of hippism, (3) unfinished edge, which emphasized the image of poverty and incompleteness, (4) irregular lace knitting and slash technique, which is the typical details of grunge look and denies the traditional fashion order, (5) hand stitch technique using various materials, which gives second-hand mood of hippie look, and (6) fringe details, which originated from the unfinished edge technique.

  • PDF

A Numerical Study on Efficiency and Convergence for Various Implicit Approximate Factorization Algorithms in Compressible Flow Field. (다양한 근사인수분해 알고리즘을 이용하여 압축성 유동장의 수렴성 및 유용성에 대한 연구)

  • Gwon Chang-O;Song Dong-Ju
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1999.11a
    • /
    • pp.17-22
    • /
    • 1999
  • Convergence characteristics and efficiency of three implicit approximate factorization schemes(ADI, DDADI and MAF) are examined using 2-Dimensional compressible upwind Navier-Stokes code. Second-order CSCM(Conservative Supra Characteristic Method) upwind flux difference splitting method with Fromm scheme is used for the right-hand side residual evaluation, while generally first-order upwind differencing is used for the implicit operator on the left-hand side. Convergence studies are performed using an example of the flow past a NACA0012 airfoil at steady transonic flow condition, i. e. Mach number 0.8 at $1.25^{\circ}$ angle of attack. The results were compared with other computational results in order to validate the current numerical analysis. The results from the implicit AF algorithms were compared well in low surface with the other computational results; however, not well in upper surface. It might be due to lack of the grid around the shock position. Because the algorithm minimizes the errors of the approximate decomposition, the improved convergence rate with MAF were observed.

  • PDF

A COUNTER-BASED MAC REVISITED: WEAKENING THE UNDERLYING ASSUMPTION

  • Lee, Eon-Kyung;Lee, Sang-Jin
    • Journal of applied mathematics & informatics
    • /
    • v.24 no.1_2
    • /
    • pp.461-470
    • /
    • 2007
  • In CRYPTO 1995, Bellare, $Gu\'{e}rin$, and Rogaway proposed a very efficient message authentication scheme. This scheme is secure against adaptive chosen message attacks, under the assumption that its underlying primitive is a pseudorandom function. This article studies how to weaken that assumption. For an adaptive chosen message attack, we take into account two scenarios. On the one hand, the adversary intercepts the authenticated messages corresponding to messages chosen adaptively by herself, so the verifier does not receive them. On the other hand, the adversary can only eavesdrop the authenticated messages corresponding to messages chosen adaptively by herself, so the verifier receives them. We modify the original scheme. In the first scenario, our scheme is secure if the underlying primitive is a pseudorandom function. In the second scenario, our scheme is still secure under a weaker assumption that the underlying primitive is an indistinguishable-uniform function.

Representation of hand written decimal digits by n sequence of fuzzy sets

  • Moon, Byung-Soo;Hwang, In-Koo
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.2 no.3
    • /
    • pp.237-241
    • /
    • 2002
  • In this paper, we describe how to represent hand witten decimal digits by a sequence of one to five fuzzy sets. Each fuzzy set represents an arc segment of the digit and is a Cartesian product of four fuzzy sets; the first is fur the arc length of the segment, the second is for the arc direction, the third is fur the arc shape, and the fourth is a crisp number indicating whether it has a junction point and if it has an end point of a stroke. We show that an arbitrary pair of these sequences representing two different digits is mutually disjoint. We also show that various forms of a digit written in different styles can be represented by the same sequence of fuzzy sets and hence the deviations due to different writers can be modeled by using these fuzzy sets.

On the Syllabic Consonants in Present-Day English

  • Oda, Toshihiro
    • Proceedings of the KSPS conference
    • /
    • 2000.07a
    • /
    • pp.189-198
    • /
    • 2000
  • /$t{\partial}n$/, /$d{\partial}n$/, /$t{\partial}l$/ and /d{\partial}l$/, on the one hand, are the typical phonemes of syllabic consonants. On the other hand, /${\int}{\partial}n$/ most plausibly gives rise to the syllabic consonants. /$t{\partial}r$/ and /$d{\partial}r/ can he syllabic. However, because lip-rounded consonants strengthen the character of consonantal phonemes, they are not so appropriate. Apart from phonemes, some familiar words also could be almost always syllabic. From the historical perspective, we can say that the position of syllabic consonants is typically the second syllables of two-syllabic words and 1.hat the underlying schwa does not always exist. In terms of the syllable structure, the syllables which include syllabic consonants are totally different from both stressed syllables and the other unstressed syllables.

  • PDF

Development of Manipulator for Vertically Moving Multi-Joint Apple Harvesting Robot(I) -Design.Manusacturing- (수직 다관절 사과수확로봇의 매니퓰레이터 개발 (I) -설계.제작-)

  • 장익주
    • Journal of Biosystems Engineering
    • /
    • v.25 no.5
    • /
    • pp.399-408
    • /
    • 2000
  • This study is final focused on developing fruit harvesting robot can distinguish fruit type and status accurately. Multi-joint robot is able to discriminate tree shape and select mature fruit by image processing. The multi-joint robot consists of (a) rotating base, (b)turning first joint-arm, (c)rotating and turning second joint-arm, (d)rotating and turning third joint-arm, (e)rotating and turning last joint and (f)picker hand. The operational ranges of the robot are: horizontal 860~2,220mm, vertical 1,440~2,260mm, 270 degrees’rotation angle, 90 or 270 degrees’turning angle. The robot weighs 330kg. The multi-joint robot was designed in high accuracy and efficiency by getting as close as the movements of human arms and waist.

  • PDF

Flexor Tendon Rupture Secondary to Gout

  • Jeremy V. Lynn;Amy L. Strong;Kevin C. Chung
    • Archives of Plastic Surgery
    • /
    • v.50 no.5
    • /
    • pp.492-495
    • /
    • 2023
  • Extra-articular deposition of monosodium urate crystals is a widely recognized manifestation of gout. However, gouty infiltration of flexor tendons in the hand resulting in tendon rupture is exceedingly rare. This case report highlights a patient with gouty infiltration of flexor tendons in the right middle finger resulting in rupture of both the flexor digitorum profundus and flexor digitorum superficialis. Given the extent of gouty infiltration and need for pulley reconstruction, the patient was treated with two-stage flexor tendon reconstruction. Febuxostat was prescribed preoperatively to limit further deposition of monosodium urate crystals and continued postoperatively to maximize the potential for long-lasting results. Prednisone was prescribed between the first- and second-stage operations to prevent a gout flare while the silicone rod was in place. In summary, tendon rupture secondary to gouty infiltration is the most likely diagnosis in patients with a history of gout presenting with tendon insufficiency.

Delayed Analysis of Hydrogen-Methane Breath Samples

  • Willemsen, Marjolein;Van De Maele, Kristel;Vandenplas, Yvan
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.25 no.1
    • /
    • pp.13-20
    • /
    • 2022
  • Purpose: Hydrogen-methane breath tests are used to diagnose carbohydrate malabsorption and small intestinal bacterial overgrowth. The COVID-19 pandemic has driven the modification of procedures as breath tests are potentially aerosol-generating procedures. We assessed the effect of delayed analysis of breath samples, facilitating the at-home performance of breath testing. Methods: Children provided two breath samples at every step of the lactose breath test. The samples were brought back to the clinic, and one set of samples was analyzed immediately. The second set was stored at room temperature and analyzed 1-4 days later. Results: Out of the 73 "double" lactose breath tests performed at home, 33 (45.8%) were positive. The second samples were analyzed 20 to 117 hours after the first samples (41.7±24.3 hours). There was no significant difference in the hydrogen concentration between the first and second sets (Z=0.49, p=0.62). This was not the case for methane, which had a significantly higher concentration in the second breath samples (Z=7.6). Conclusion: Expired hydrogen levels remain stable in plastic syringes if preserved at room temperature for several days. On the other hand, the delayed analysis of methane appeared to be less reliable. Further research is needed to examine the impact of delayed analysis on methane and hydrogen concentrations.

Investigation on the Generalized Hydrodynamic Force and Response of a Flexible Body at Different Reference Coordinate System (기준 좌표계에 따른 탄성체의 일반화 파랑 하중 및 응답에 대한 연구)

  • Heo, Kyeonguk;Choi, Yoon-Rak
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.58 no.6
    • /
    • pp.348-357
    • /
    • 2021
  • In this paper, the generalized hydrodynamic force and response of a flexible body are calculated at different reference coordinate systems. We generalize the equation of motion for a flexible body by using the conservation of momentum (Mei et al., 2005). To obtain the equations in the generalized mode, two different reference coordinates are adopted. The first is the body-fixed coordinate system by a rigid body motion. The other is the inertial coordinate system which has been adopted for the analysis. Using the perturbation scheme in the weakly-nonlinear assumption, the equations of motion are expanded up to second-order quantities and several second-order forces are obtained. Numerical tests are conducted for the flexible barge model in head waves and the vertical bending is only considered in the hydroelastic responses. The results show that the linear response does not have the difference between the two formulations. On the other hand, second-order quantities have different values for which the rigid body motion is relatively large. However, the total summation of second-order quantities has not shown a large difference at each reference coordinate system.