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An ID-Based Remote User Authentication Scheme in IoT (사물인터넷에서 ID기반 원격 사용자 인증 방식)

  • Park, KiSung;Lee, SungYup;Park, YoHan;Park, YoungHo
    • Journal of Korea Multimedia Society
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    • v.18 no.12
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    • pp.1483-1491
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    • 2015
  • Applications of Internet of Things (IoT) supply various conveniences, however unsolved security problems such as personal privacy, data manipulation cause harm to persons, even nations and an limit the applicable areas of Internet of IoT technology. Therefore, study about secure and efficient security system on IoT are required. This paper proposes ID-based remote user authentication scheme in IoT environments. Proposed scheme provides untraceability of users by using different pseudonym identities in every session and reduces the number of variables. Our proposal is secure against inside attack, smart card loss attack, user impersonation attack, server masquerading attack, online/offline password guessing attack, and so on. Therefore, this can be applied to the lightweight IoT environments.

Carotidynia presenting with acute ischemic stroke after carotid sinus massage

  • Kwak, Hyo Sung;Chung, Gyung Ho;Lee, Chan-Hyuk;Jeong, Seul-Ki;Ryu, Han Uk
    • Annals of Clinical Neurophysiology
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    • v.19 no.1
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    • pp.46-49
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    • 2017
  • Carotidynia is characterized by unilateral neck pain around the carotid artery. We describe a 50-year-old woman who presented with transient left-side weakness and right-side neck pain. She frequently massaged the uncomfortable neck area during the symptomatic course of the condition. Magnetic resonance imaging revealed multifocal cerebral infarctions and a carotid intramural thrombus ipsilateral to the carotidynia.Long-term carotidynia might result in the involvement of an intramural thrombus and intimal disruption, and ischemic stroke after carotidynia may be provoked by carotid sinus massage.

Extended Parity Space Techniques for Fault Detection in Parallel Power Supply (확장 패리티 공간 기법을 이용한 병렬 전원 장치 고장검출 기법)

  • Choi, Sang Ui;Lee, Yoen Seok;Park, Gun Pil;Jung, Sam Ki;Ra, In Ho
    • Proceedings of the Korea Contents Association Conference
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    • 2016.05a
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    • pp.425-426
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    • 2016
  • ICT(Information and Communications Technologies)의 빠른 발전으로 직류 전원의 직접 사용이 증가하고 있다. 그러나 대용량 가변가능 직류 전원 장치가 보편화되지 않았으며 현재 ICT 기기들은 내부 또는 외부에 직류 전원 정류 장치를 내장하고 있다. 앞으로 더욱더 많은 기기들이 교류 전원이 아닌 직류 전원을 사용하게 되므로 가변이 가능한 대용량의 직류 전원 장치가 필요하게 될 것이다. 그러나 가변 가능한 구조의 전원장치는 다수의 전원 장치를 병렬로 연결하여야 하므로 고장에 대한 검출 및 분리가 필요하게 된다. 이러한 고장 검출을 위하여 확장 패리티 공간 기법을 적용하였다.

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Cloning of a Bacillus subtilis WL-7 Mannanase Gene and Characterization of the Gene Product

  • KWEUN , MIN-A;LEE, MI-SUNG;CHOI, JOON-HO;CHO, KI-HAENG;YOON, KI-HONG
    • Journal of Microbiology and Biotechnology
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    • v.14 no.6
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    • pp.1295-1302
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    • 2004
  • A gene encoding the mannanase of Bacillus subtilis WL-7, which had been isolated from Korean soybean paste, was cloned into Escherichia coli, and the gene product was purified from the culture filtrate of the recombinant E. coli. This mannanase gene, designated manA, consisted of 1,086 nucleotides, encoding a polypeptide of 362 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to the glycosyl hydrolase family 26. The molecular mass of the purified mannanase was 38 kDa as estimated by SDS-PAGE. The enzyme had a pH optimum at 6.0 and a temperature optimum at $55^{\circ}C$. The enzyme was active on locust bean gum, konjak, guar gum, and lichenan, while it did not exhibit activity towards yeast mannan, laminarin, carboxymethylcellulose, $\beta$­glucan, xylan, and para-nitrophenyl-$\beta$-mannopyranoside.

Design of Multilayered Suspension Mechanism for Differential Type Mobile Robot

  • Park, Jin-Ho;Roh, Se-Gon;Park, Ki-Heung;Kim, Hong-Seok;Lee, Ho-Gil;Choi, Hyouk-Ryeol
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.859-864
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    • 2003
  • This paper presents a design for the novel suspension mechanism of a two-wheeled mobile robot having two casters which is used for indoor environment. Although the indoor environment is less rough than the outdoor one, the fixed caster mechanism has some problems such as causing the robot to be immovable because robot's driving wheels do not have contact with the ground. Therefore, we tried installing a spring-damper suspension mechanism to keep driving capability and to remove pitching phenomenon. However, this suspension mechanism also has the problem, which the robot body inclined by disturbances does not return to the initial position. To deal with above problems and to accomplish desired performances, we designed the Multilayered Suspension Mechanism, which has springs and dampers working partially according to the inclined angle and angular velocity of robot body concerned with pitching. To analyze design, the equations of motion describing their dynamics were developed. Using the equations, simulation results show the improved performance. We confirm the usefulness of the Multilayered Suspension Mechanism by construction and test of a actual prototype.

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Wear Behaviors of Gas Atomized and Extruded Hypereutectic Al-Si Alloys (가스분무 공정에 의한 과공정 Al-Si 합금 분말 압출재의 마모 거동)

  • Jin Hyeong-Ho;Nam Ki-Young;Kim Yong-Jin;Park Yong-Ho;Yoon Seog-Young
    • Journal of Powder Materials
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    • v.13 no.4 s.57
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    • pp.250-255
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    • 2006
  • Wear behaviors of gas atomized and extruded Al-Si alloys were investigated using the dry sliding wear apparatus. The wear tests were conducted on Al-Si alloy discs against cast iron pins and vice versa at constant load of 10N with different sliding speed of 0.1, 0.3, 0.5m/s. In the case of Al-Si alloy discs slid against the cast iron pins, the wear rate slightly increased with increasing the sliding speed due to the abrasive wear occurred between Al-Si alloy discs and cast iron pins. Conversely, in the case of cast iron discs against Al-Si alloy pins, the wear rate decreased with increasing the sliding speed up to 0.3m/s. However, the wear rate increased with increasing the sliding speed from 0.3m/s to 0.5m/s. It could be due to adhesive wear behavior and abrasive wear behavior_between cast iron discs and Al-Si alloy pins.

The Effect of MgO Content on the Preparation of Porous Hydroxyapaite Scaffolds by Polymer Sponge Method (폴리머 스펀지법을 이용한 다공성 수산화아파타이트 지지체 제조 시 MgO 첨가량에 따른 영향)

  • Jin, Hyeong-Ho;Min, Sang-Ho;Lee, Won-Ki;Park, Hong-Chae;Yoon, Seog-Young
    • Korean Journal of Materials Research
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    • v.16 no.11
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    • pp.715-718
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    • 2006
  • Porous hydroxyapatite (HAp) scaffolds have been prepared by using the slurry including HAp and magnesia based on the replication of polymer sponge substrate. The influence of MgO content in slurry on the pore morphology and size, density, porosity, and mechanical strength of porous HAp scaffolds was investigated. The obtained scaffolds with average pore sizes ranging 150 to 300 mm had open, relatively uniform, and interconnected porous structure regardless of MgO content. As the MgO content increased, the pore network frame of scaffolds became to be relatively stronger, even though the pore size was not much changed. The compressive strength of the scaffolds increased rapidly with the increase of MgO content because of increasing the pore wall thickness and density of the scaffolds. As a result, the porosity, density, and compressive strength of the porous HAp scaffolds prepared by the sponge method were significantly affected by the addition of MgO.

A Case of Parkinson's Disease Patient with Nausea and Vomiting Induced by Taking Levodopa (레보도파 복용으로 유발된 오심 및 구토를 호소하는 파킨슨병 환자 한방 치험 1례)

  • Kim, Se-won;Yang, Jung-yun;Lee, Yu-jin;Cho, Ki-ho;Jung, Woo-sang;Kwon, Seung-won;Choi, Ki-mun;Mun, Sang-kwan
    • The Journal of Internal Korean Medicine
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    • v.40 no.2
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    • pp.246-253
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    • 2019
  • Objective: In this care report, we address a case of a Parkinson's disease patient with nausea and vomiting. Methods: A patient was treated with Korean medicine therapies including herbal medication (Hyungbangjihwang-tang, Boikyangwie-tang), acupuncture, and electroacupuncture during 35 days of hospitalization. We evaluated the improvements of symptoms by checking the number of vomiting episodes and the presence of nausea. Results: During 35 days of Korean medicine treatment, there was improvement in patient's symptoms. The frequency of vomiting had decreased, and the nausea had decreased and not appeared for the last 7 days. Conclusions: This study suggested that Korean medicine therapies might be effective in relieving gastrointestinal symptoms of Parkinson's disease.

Analyzed of the Circular Dielectric Rod Antenna Having Sing1y Fed CP Microstrip Antenna (단일급전 마이크로스트립 안테나를 사용한 유전체 봉 안테나의 해석)

  • Chun, Young-Ho;Chung, Hawn-Yong;Chung, Dae-Sik;Ko, Ji-Hwan;Cho, Young-Ki
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2005.11a
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    • pp.367-370
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    • 2005
  • In this paper, we made a Singly Fed patch which is the fittest at the feeding part. And we found out return loss and radiation pattern about dielectric rod array antenna which has six's passive element to shape FTEP(Flat-topped element pattern) after we analyzed the characters of singly dielectric rod antenna. We show the conclusion that has the optimum return loss and more flat radiation pattern.

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