• 제목/요약/키워드: Lock-on

검색결과 886건 처리시간 0.026초

주기적으로 회전진동하는 원주 후류의 공진특성 (Lock-on Characteristics of wake behind a Rotationally Oscillating Circular Cylinder)

  • 이정엽;이상준
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2004년도 추계학술대회 논문집
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    • pp.18-21
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    • 2004
  • Lock-on characteristics of the flow around a circular cylinder performing a rotationally oscillation with a relatively high forcing frequency have been investigated experimentally using flow visualization and hot-wire measurements. Dominant parameters are Reynolds number (Re), amplitude of oscillation $(\theta_A)$, and frequency ratio $F_R=f_f\;/\;f_n$, where $f_f$ is the forcing frequency and if is the natural frequency of vortex shedding. Experiments were carried out under the conditions of $Re=4.14\times10^3,\;\pi/15\leq\theta_A\leq\pi/3$, and $F_R=1.0$. The effects of this active control technique on the lock-on flow regime of the cylinder wake were evaluated through wake velocity measurements and spectral analysis of hot-wire signals. The rotary oscillation modified the flow structure of near wake significantly. The lock-on phenomenon was found to occur in the range of frequency encompassing the natural vortex shedding frequency. In addition, when the amplitude of oscillation is less than a certain value, the lock-on phenomenon was occurred only at $F_R=1.0$. The lock-on range expanded and vortex formation length decreased as the amplitude of oscillation increases. The rotary oscillation generated small-scale vortex structure just near the cylinder surface.

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문 잠금 조정장치에 관한 사용자 기대 및 선호도 (User Expectations and Preferences of Door Lock Control Devices)

  • 정화식;정형식
    • 대한산업공학회지
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    • 제29권4호
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    • pp.283-291
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    • 2003
  • The purposes of this study are to investigate the stereotype of position and direction that users expect door lock control devices in different orientations, and to collect information regarding preferred door lock design and orientations. Six hundred subjects aged from lOs to 60s were surveyed under the operating conditions of three different door locks(cylindrical, circular-type, and lever-type auxiliary locks) mounted on the miniature door in two different orientations(right and left side). The door locks presented to the subjects were the most widely used door locks in our living environment. The results indicated that if the door locks were seen from the inside, 59~67% of the subjects expected 'vertical' position locking depending on the door lock control types, cylinder or auxiliary lock. When the door locks were seen from the outside, the locking direction of door lock control was not consistent either 'clockwise' or 'counterclockwise'. It was rather dependent on the orientation of the door lock positions. As a concluding remark, it is better to design and install door lock control devices in the way that users expect them to work.

암호화기술을 적용한 무선 도어락시스템 디자인에 대한 연구 (A Study on the Wireless Door Lock System with Advanced Encryption Standard(AES) in Design)

  • 유보현
    • 디자인학연구
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    • 제17권1호
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    • pp.179-190
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    • 2004
  • 개인생활의 프라이버시와 외부로부터 자신의 안전성(Safety)을 확보하고자하는 노력은 오늘날 기술의 진보와 더불어 보안시스템의 발전을 가져왔다. 특히 아파트형태의 주거생활이 보편화되면서 프라이버시의 확보와 외부침입으로부터 자신과 가족의 보호라는 측면에서 도어락시스템(Door Lock System)의 역할과 기능의 중요성이 증대되고 있다. 이러한 추세에 발맞추어 기술의 발전뿐만 아니라 사용자중심의 다양한 방법의 인터페이스에 대한 연구가 이뤄지고 있으며 그 일환으로 지문이나 홍체인식과 같은 최첨단의 보안시스템이 등장하고 있다. 본 연구는 암호화기술(Advanced Encryption Standard)을 적용하여 보안과 안전성을 확보함과 동시에 사용자가 쉽게 작동하고 사용할 수 있는 인터페이스를 바탕으로 한 도어락 개발에 초점을 두고 있다. 특히 가격 면에서도 기존제품과 경쟁력을 가질 수 있고, 보다 근본적으로 도어락 뿐만 아니라 전반적인 잠금장치에 대한 새로운 가능성과 방법을 모색해 봄으로써 향후 잠금장치와 보안시스템에 대한 대안을 제시코자 한다.

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인천항 갑문의 운영 수준에 관한 연구 (A Study on the Operational Utilization Levels of Lock Gates in Inchon Port)

  • 구자윤
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2002년도 춘계학술대회논문집
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    • pp.13-19
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    • 2002
  • In inner harbour of Inchon Port, there are two lock gates (50KT, 10KT) which have two gates per lock gate in inner/outer sides except a gate in inner harbour side 7f 10KT. Due to the lack of the fore-mentioned gate, the use of 10KT lock gate Is suspended in every 3 years for regular maintenance. Now an additional gate is under construction in order to improve the efficiency of the 10KT lock gate. This paper will be aimed to evaluate the operational utilization levels of lock gates in present and future. The present operational utilization levels of lock gates are 0.2119 in 10KT lock gate, 0.2051 in 50KT lock gate which were considered the 46.5 closed days every 3 years for 10KT regular maintenance. The levels are estimated to 0.2246(10KT), 0.2539(50KT) in 2006 and 0.2241(10KT), 0.2560(50KT) in 2011. The levels of 50KT lock gate are evaluated to be more rapidly increased up to 24.5% in 2011.

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원형 스마트폰 잠금 패턴 방식 제안 (A proposal of Circular Lock Pattern Method on Smart phone)

  • 임지우;이승재;장원준;권혁동;서화정
    • 한국정보통신학회논문지
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    • 제23권11호
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    • pp.1471-1477
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    • 2019
  • 스마트폰에는 현재 다양한 보안 방식이 사용되고 있다. 그중에서도 핀 번호와 패턴 잠금 방식은 초기 스마트폰부터 사용되었을 정도로 오래 사용되었다. 하지만 패턴 잠금 방식은 오래 사용된 만큼 보안이 취약하다. 핀 번호 방식의 보안 강도가 약간 높은 정도라면 패턴 잠금 방식은 중간 정도에 그친다. 그럼에도 많은 스마트폰 사용자들은 패턴 잠금 방식을 이용하고 있는데 아직 생체보안을 지원하지 않는 기종을 사용하는 사용자가 있기 때문이다. 생체보안을 지원하지 않는 기종에서 제일 편리한 보안 방식은 패턴 잠금 방식이다. 그러나 기존의 패턴 잠금 방식은 Shoulder surfing attack과 Smudge attack에 취약하다. 따라서 패턴 잠금 방식의 편리성을 유지하면서 동시에 기존 방식의 취약점을 해결하는 방식을 제안하고자 한다. 제안하는 방식은 화면에 배치되는 각각의 점을 원형으로 배치한 뒤 무작위로 숫자를 부여하는 잠금 방식이다. 본 방식을 도입하게 된다면 기존의 취약점을 상당히 해결할 수 있다. 즉, 기존의 패턴 잠금 방식에 비해 보안성을 높일 수 있다.

자유회전 테일핀을 갖는 미사일에 대한 Roll Lock-in 현상의 수치적 연구 (A NUMERICAL STUDY ON THE ROLL LOCK-IN OF A CANARD-CONTROLLED MISSILE WITH FREELY SPINNING TAILFINS)

  • 양영록;김문석;명노신;조태환
    • 한국전산유체공학회지
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    • 제14권4호
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    • pp.48-55
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    • 2009
  • In this study, roll lock-in phenomena of freely spinning tailfins were investigated by a CFD code. To analyze a motion of freely spinning tailfins, this research use a Chimera method, an Euler code and a 6 degrees of freedom analysis. The numerical results of aerodynamic characteristics and roll rates of a canard-controlled missile with freely spinning tailfins show a good agreement with wind tunnel test results. Using the roll rates calculation result of freely spinning tailfins, roll lock-in phenomena is confirmed. Roll lock-in phenomena and Roll lock-in states can be predicted through effects of the induced vortex of the canards control and the analysis of the rolling moments of tailfins due to the bank angle.

빠른 lock-on time을 위한 선택적 시작점을 갖는 DLL (A Fast lock-on time Delay Locked Loop with selective starting point)

  • 김신호;장일권;곽계달
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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    • pp.79-82
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    • 2000
  • This paper describes a delay locked loop with selective starting point for use in a high-frequency systems. SSRDLL (selective starting point RDLL) has been simulated in a 0.25$\mu\textrm{m}$ standard n-well CMOS process parameter to realize a fast lock-on time. This DLL is shown to be insensitive to variations in PVTL. The simulated lock time of the proposed SSRDLL is within 4 clock cycles at 333㎒ clock input.

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고려재조대장목록고 (A study on the second edition of Koryo Dae-Jang-Mock-Lock)

  • 정필모
    • 한국문헌정보학회지
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    • 제17권
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    • pp.11-47
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    • 1989
  • This study intends to examine the background and the procedure of the carving of the tablets of the second edition of Dae-Jang-Mock­Lock(재조대장목록). the time and the route of the moving of the tablets. into Haein-sa, and the contents and the system of it. This study is mainly based on the second edition of Dae-Jang-Mock-Lock. But the other closely related materials such as restored first. edition of the Dae- Jang-Mock-Lock, Koryo Sin-Jo-Dae-Jang-Byeol-Lock (고려신조대장교정별록). Kae-Won-Seok-Kyo-Lock (개원석교록). Sok-Kae­Won-Seok-Kyo-Lock (속개원석교록). Jeong-Won-Sin-Jeong-Seok-Kyo­Lock(정원신정석교록), Sok-Jeong-Won-Seok-Kyo-Lock(속정원석교록), Dea-Jung-Sang-Bu-Beob-Bo-Lock(대중상부법보록), and Kyeong-Woo-Sin-Su-Beob-Bo-Lock(경우신수법보록), are also analysed and closely examined. The results of this study can be summarized as follows: 1. The second edition of Tripitaka Koreana(고려대장경) was carved for the purpose of defending the country from Mongolia with the power of Buddhism, after the tablets of the first edition in Buin-sa(부이사) was destroyed by fire. 2. In 1236. Dae-Jang-Do-Gam(대장도감) was established, and the preparation for the recarving of the tablets such as comparison between the content, of the first edition of Tripitalk Koreana, Gal-Bo-Chik-Pan-Dae­Jang-Kyeong and Kitan Dae- Jang-Kyeong, transcription of the original copy and the preparation of the wood, etc. was started. 3. In 1237 after the announcement of Dae-Jang-Gyeong-Gak-Pan-Gun­Sin-Gi-Go-Mun(대장경핵판군신석고문), the carving was started on a full scale. And seven years later (1243), Bun-Sa-Dae-Jang-Do-Gam(분사대장도감) was established in the area of the South to expand and hasten the work. And a large number of the tablets were carved in there. 4. It took 16 years to carve the main text and the supplements of the second edition of Tripitaka Koreana, the main text being carved from 1237 to 1248 and the supplement from 1244 to 1251. 5. It can be supposed that the tablets of the second edition of Tripitaka Koreana, stored in Seon-Won-Sa(선원사), Kang-Wha(강화), for about 140 years, was moved to Ji-Cheon-Sa(지천사), Yong-San(용산), and to Hae-In-Sa(해인사) again, through the west and the south sea and Jang-Gyeong-Po(장경포), Go-Ryeong(고령), in the autumn of the same year. 6. The second edition of Tripitaka Koreana was carved mainly based on the first edition, comparing with Gae-Bo-Chik-Pan-Dae-Jang-Kyeong(개보판대장경) and Kitan Dae-Jang-Kyeong(계단대장경). And the second edition of Dae-Jang-Mock-Lock also compiled mainly based on the first edition with the reference to Kae-Won-Seok-Kyo-Lock and Sok-Jeong-Won-Seok-Kyo-Lock. 7. Comparing with the first edition of Dae-Jang-Mock-Lock, in the second edition 7 items of 9 volumes of Kitan text such as Weol-Deung­Sam-Mae-Gyeong-Ron(월증삼매경론) are added and 3 items of 60 volumes such as Dae-Jong-Ji-Hyeon-Mun-Ron(대종지현문논) are substituted into others from Cheon chest(천함) to Kaeng chest(경함), and 92 items of 601 volumes such as Beob-Won-Ju-Rim-Jeon(법원주임전) are added after Kaeng chest. And 4 items of 50 volumes such as Yuk-Ja-Sin-Ju-Wang-Kyeong(육자신주왕경) are ommitted in the second edition. 8. Comparing with Kae-Won-Seok-Kyo-Lock, Cheon chest to Young chest (영함) of the second edition is compiled according to Ib-Jang-Lock(입장록) of Kae-Won-Seok-Kyo-Lock. But 15 items of 43 vol­umes such as Bul-Seol-Ban-Ju-Sam-Mae-Kyeong(불설반주삼매경) are ;added and 7 items of 35 volumes such as Dae-Bang-Deung-Dae-Jib-Il­Jang-Kyeong(대방등대집일장경) are ommitted. 9. Comparing with Sok-Jeong-Won-Seok-Kyo-Lock, 3 items of the 47 volumes (or 49 volumes) are ommitted and 4 items of 96 volumes are ;added in Caek chest(책함) to Mil chest(밀함) of the second edition. But the items are arranged in the same order. 10. Comparing with Dae- Jung-Sang-Bo-Beob-Bo-Lock, the arrangement of the second edition is entirely different from it. But 170 items of 329 volumes are also included in Doo chest(두함) to Kyeong chest(경함) of the second edition, and 53 items of 125 volumes in Jun chest(존함) to Jeong chest(정함). And 10 items of 108 volumes in the last part of Dae-Jung-Sang-Bo-Beob-Bo-Lock are ommitted and 3 items of 131 volumes such as Beob-Won-Ju-Rim-Jeon(법원주임전) are added in the second edition. 11. Comparing with Kyeong-Woo-Sin-Su-Beob-Bo-Lock, all of the items (21 items of 161 volumes) are included in the second edition without ;any classificatory system. And 22 items of 172 volumes in the Seong­Hyeon-Jib-Jeon(성현집전) part such as Myo-Gak-Bi-Cheon(묘각비전) are ommitted. 12. The last part of the second edition, Joo chest(주함) to Dong chest (동함), includes 14 items of 237 volumes. But these items cannot be found in any other former Buddhist catalog. So it might be supposed as the Kitan texts. 13. Besides including almost all items in Kae-Won-Seok-Kyo-Lock and all items in Sok-Jeong-Won-Seok-Kyo-Lock, Dae-Jung-Sang-Bo­Beob-Bo-Lock, and Kyeong-Woo-Sin-Su-Beob-Bo-Lock, the second edition of Dae-Jang-Mock-Lock includes more items, at least 20 items of about 300 volumes of Kitan Tripitaka and 15 items of 43 volumes of traditional Korean Tripitake that cannot be found any others. Therefore, Tripitaka Koreana can be said as a comprehensive Tripitaka covering all items of Tripitakas translated in Chinese character.

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스마트 폰 잠금 화면을 통한 실시간 정보제공 서비스 모델의 개발 (Development of Real Time Information Service Model Using Smart Phone Lock Screen)

  • 오성진;장진욱
    • 한국IT서비스학회지
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    • 제13권3호
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    • pp.323-331
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    • 2014
  • This research is based on real-time service model that uses lock screen of smart devices which is mostly exposed to device users. The potential for lock screen space is immense due to their exposing time for user. The effect can be maximized by offering useful information contents on lock screen. This service model offers real-time keyword with abridged sentence. They match real-time keyword with news by using text matching algorithm and extracts kernel sentence from news to provide short sentence to user. News from the lock screen to match real-time query sentence, and then only to the original core of the ability to move a user evaluation was conducted after adding. The report provided a key statement users feel the lack of original Not if you go to an average of 5.71%. Most algorithms allow only real-time zoom key sentence extracted keywords can accurately determine the reason for that was confirmed.

비접촉식 지문방지 도어락 시스템 구현 (The Implementation of Non-contact Door-lock System for Preventing Fingerprint)

  • 김현옥;문광수;김승규;김두용;김기완
    • 반도체디스플레이기술학회지
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    • 제13권4호
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    • pp.77-81
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    • 2014
  • There have been developed in authentication systems for information using biometric information approaches such as fingerprint, face, and iris. In general, a door-lock system is operated by touching keypads, which remains fingerprints on the keypads. Such door-lock systems do not protect personal information from others due to the exposure of fingerprints to keypads. In this paper, we propose the new door-lock system that does not leave fingerprints on the keypads. Without touching keypad the system works because the system accepts authentication information by using illuminance sensor and LED. The experiment shows that the implemented door-lock system works well under any circumstance.