• Title/Summary/Keyword: 리프팅

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A Study of Strength Evaluation of Crankshaft Lifting Pin for Reducing Weight (대형 크랭크축 리프팅 핀의 경량화를 위한 강도평가 연구)

  • Jeon, Byung-Young;Kim, Byung-Joo;Park, Jong-Du
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.7-12
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    • 2004
  • Large-sized pins are usually used to lift and handle large low speed diesel engine crankshaft. There has then been a need to reduce and optimize the weight of the traditionally used pins. Making an hole by cutting the inside of the pin out was investigated in view of static and fracture strength. To compensate the stress increase caused by the introduction of the inner hole, the groove in the circumferential direction pre-existing on the pin is to be removed. Finite element analysis was carried out for both the original model and weight reduced model. Stress intensity factors for semi-elliptical defects assumed on the pin for the original model and weight reduced model was calculated using the ASME method and compared with the fracture toughness test result of the pin material. The diameter of the cutting hole for the revised model was determined based on the analysis results.

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A Study on Error-Resilient, Scalable Video Codecs Based on the Set Partitioning in Hierarchical Trees(SPIHT) Algorithm (계층적 트리의 집합 분할 알고리즘(SPIHT)에 기반한 에러에 강하고 가변적인 웨이브렛 비디오 코덱에 관한 연구)

  • Inn-Ho, Jee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.1
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    • pp.37-43
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    • 2023
  • Compressed still image or video bitstreams require protection from channel errors in a wireless channel. Embedded Zerotree Coding(EZW), SPIHT could have provided unprecedented high performance in image compression with low complexity. If bit error is generated by dint of wireless channel transmission problem, the loss of synchronization on between encoder and decoder causes serious performance degradation. But wavelet zerotree coding algorithms are producing variable-length codewords, extremely sensitive to bit errors. The idea is to partition the lifting coefficients. A many partition of lifting transform coefficients distributes channel error from wireless channel to each partition. Therefore synchronization problem that caused quality deterioration in still image and video stream was improved.

Structural Evolution of the Eastern Margin of Korea: Implications for the Opening of the East Sea (Japan Sea) (한국 동쪽 대륙주변부의 구조적 진화와 동해의 형성)

  • Kim Han-Joon;Jou Hyeong-Tae;Lee Gwang-Hoon;Yoo Hai-Soo;Park Gun-Tae
    • Economic and Environmental Geology
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    • v.39 no.3 s.178
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    • pp.235-253
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    • 2006
  • We interpreted marine seismic profiles in conjunction with swath bathymetric and magnetic data to investigate rifting to breakup processes at the Korean margin leading to the separation of the Japan Arc. The Korean margin is rimmed by fundamental elements of rift architecture comprizing a seaward succession of a rift basin and an uplifted rift flank passing into the slope, typical of a passive continental margin. In the northern part, rifting occurred in the Korea Plateau, a continental fragment extended and partially segmented from the Korean Peninsula, that provided a relatively broader zone of extension resulting in a number of rifts. Two distinguished rift basins (Onnuri and Bandal Basins) in the Korea Plateau we bounded by major synthetic and smaller antithetic faults, creating wide and symmetric profiles. The large-offset border fault zones of these basins have convex dip slopes and demonstrate a zig-zag arrangement along strike. In contrast, the southern margin is engraved along its length with a single narrow rift basin (Hupo Basin) that is an elongated asymmetric half-graben. Rifting at the Korean margin was primarily controlled by normal faulting resulting from extension in the west and southeast directions orthogonal to the inferred line of breakup along the base of the slope rather than strike-slip deformation. Although rifting involved no significant volcanism, the inception of sea floor spreading documents a pronounced volcanic phase which seems to reflect slab-induced asthenospheric upwelling as well as rift-induced convection particularly in the narrow southern margin. We suggest that structural and igneous evolution of the Korean margin can be explained by the processes occurring at the passive continental margin with magmatism intensified by asthenospheric upwelling in a back-arc setting.

Hardware Architecture of High Performance Cipher for Security of Digital Hologram (디지털 홀로그램의 보안을 위한 고성능 암호화기의 하드웨어 구조)

  • Seo, Young-Ho;Yoo, Ji-Sang;Kim, Dong-Wook
    • Journal of Broadcast Engineering
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    • v.17 no.2
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    • pp.374-387
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    • 2012
  • In this paper, we implement a new hardware for finding the significant coefficients of a digital hologram and ciphering them using discrete wavelet packet transform (DWPT). Discrete wavelet transform (DWT) and packetization of subbands is used, and the adopted ciphering technique can encrypt the subbands with various robustness based on the level of the wavelet transform and the threshold of subband energy. The hologram encryption consists of two parts; the first is to process DWPT, and the second is to encrypt the coefficients. We propose a lifting based hardware architecture for fast DWPT and block ciphering system with multi-mode for the various types of encryption. The unit cell which calculates the repeated arithmetic with the same structure is proposed and then it is expanded to the lifting kernel hardware. The block ciphering system is configured with three block cipher, AES, SEED and 3DES and encrypt and decrypt data with minimal latency time(minimum 128 clocks, maximum 256 clock) in real time. The information of a digital hologram can be hided by encrypting 0.032% data of all. The implemented hardware used about 200K gates in $0.25{\mu}m$ CMOS library and was stably operated with 165MHz clock frequency in timing simulation.

High-resolution Seismic Imaging of Shallow Geology Offshore of the Korean Peninsula: Offshore Uljin (신기 지구조운동의 해석을 위한 한반도 근해 천부지질의 고해상 탄성파 탐사: 울진 주변해역)

  • Kim, Han-Joon;Jou, Hyeong-Tae;Yoo, Hai-Soo;Kim, Kwang-Hee;You, Lee-Sun
    • Geophysics and Geophysical Exploration
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    • v.14 no.2
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    • pp.127-132
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    • 2011
  • We acquired and interpreted more than 650 km of high-resolution seismic reflection profiles in the Hupo Basin, offshore east coast of Korea at $37^{\circ}N$ in the East Sea (Japan Sea) to image shallow and basement deformation. The seismic profiles reveal that the main depocenter of the Hupo Basin in the study area is bounded by the large offset Hupo Fault on the east and an antithetic fault on the west; however, the antithetic fault is much smaller both in horizontal extension and in vertical displacement than the Hupo Fault. Sediment infill in the Hupo Basin consists of syn-rift (late Oligocene. early Miocene) and post-rift (middle Miocene.Holocene) units. The Hupo Fault and other faults newly defined in the Hupo Basin strike dominantly north and show a sense of normal displacement. Considering that the East Sea has been subjected to compression since the middle Miocene, we interpret that these normal faults were created during continental rifting in late Oligocene to early Miocene times. We suggest that the current ENE direction of maximum principal compressive stress observed in and around the Korean peninsula associated with the motion of the Amurian Plate induces the faults in the Hupo Basin to have reverse and right-lateral, strike-slip motion, when reactivated. A recent earthquake positioned on the Hupo Fault indicates that in the study area and possibly further in the eastern Korean margin, earthquakes would occur on the faults created during continental rifting in the Tertiary.

A Study on Development of Wrinkle Evaluation Software and Verification of Skin Wrinkle Improvement of Cog Suture (주름 평가 소프트웨어 개발과 Cog형 봉합사의 피부 주름 개선 검증에 관한 연구)

  • Jeong, Jin-Hyoung;Lee, Sang-Sik
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.4
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    • pp.336-342
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    • 2019
  • With the entry of an aging society, the average life span of accreditation has been extended. Therefore, interest in the appearance of men and women in modern society has increased. It is the wrinkles of the face that can judge the most outwardly. People tend to have various kinds of treatments to have a clean, wrinkle-free and resilient healthy skin regardless of sex. There is a lot of practice of lifting procedures in one of the procedures. A suture using a melting thread is a method of lifting by squeezing it into the skin as a non-incision type centering on a region where the thread can be fixed in the skin by injecting it into the subcutaneous fat layer. To evaluate the lifting efficacy of Cog - type suture for the improvement of skin wrinkles, preclinical experiments were conducted. We developed a wrinkle evaluation program using Labview. Data from preclinical experiments were used at 8 weeks after suturing. The average wrinkle depth was 415.6 mm in the control group. At 8 weeks, the depth of wrinkles was deepened to 888.3mm due to the aging process of the control group. On the other hand, the depth of the wrinkles before surgery was 640.3 mm in the suture group. It was confirmed that the depth of wrinkles decreased to 566.5mm at 8th week after the suture operation.

Wavelet Transform with Point-Symmetric Extension. (점대칭 확장을 이용한 웨이블릿 변환)

  • 최성훈;정원용
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2003.06a
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    • pp.86-89
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    • 2003
  • 타일링을 통해 손실 압축된 데이터에 대해 점대칭 확장(point symmetric extension)을 사용하면 경계에서의 인공물(artifact)들을 줄일 수 있다 실제 확장 샘플 없이 경계 필터(boundary filter)를 사용하는 것과 같은 효과를 내는 방법을 리프팅(lifting)을 사용하여 수행할 수 있다. 본 논문에서 사용된 필터는 PR 특성을 준수하고, 경계근처에서 어떠한 후처리 기술이나 이웃하는 타일들로부터의 추가정보 없이 경계 인공물들을 현저히 감소시켰다.

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Guideline of Weight Factor for Lifting Operation by Parallel Connected Floating Cranes and Verification using Simulation (다수대의 해상크레인 병렬 운용을 위한 리프팅 하중 Factor 적용 기준 마련 및 시뮬레이션을 통한 검증)

  • Hwang, Jin-Ho;Kim, Yun-Ho;Ha, Soo-Ho;Seo, Jeong-Gil;Lee, Chan-Young;Lee, Kyu-Yeul;Park, Kwang-Phil;Cha, Ju-Hwan
    • Special Issue of the Society of Naval Architects of Korea
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    • 2009.09a
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    • pp.107-114
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    • 2009
  • In the recent large block are used to build the ship to improve productivity. For this reason, two or more floating cranes that are connected in parallel is the trend. Typically, when working with floating crane load safety factor is considered. Even in the parallel operation, load safety factor is calculated similar to working alone. For this reason, operations do not guarantee the reliability or excessive safety factor applied. Therefore, the subdivided cases for calculating the safety factor are defined when parallel connected floating cranes are operated. Based on those cases, the operation standard is made about procedure using parallel connected floating cranes. And to verify this, dynamics simulation was performed for verification using the dynamics simulation program.

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Free Surface Procedure for Lifting Operation by Parallel Connected Floating Cranes using Synchronized Operation System and Its Applications to Lifting Operations of a Heavy Cargo (동조 시스템을 적용한 다수대의 해상크레인 병렬 운용 절차 및 대형 중량물의 리프팅 작업 적용)

  • Hwang, Jin-Ho;Ahn, Jeong-Ik;Lee, Soo-Bae;Kim, Yun-Ho;Choung, Jin-Sik;Ham, Seung-Ho;Lee, Won-Joon
    • Special Issue of the Society of Naval Architects of Korea
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    • 2009.09a
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    • pp.97-106
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    • 2009
  • Many production methods are tried to enhance the productivity efficiency. Parallel connected floating cranes are one of the examples to lift mega-blocks quickly and efficiently. However, a general operation manual to operate parallel connected floating cranes and a method to consider risks during lifting operation are not confirmed. And if each floating crane is operated by itself, it is very hard to cooperate. Therefore, Synchronized operation system is installed to control parallel connected floating cranes simultaneously and to be informed of each floating cranes data. And weighting factor is calculated by considering all hazards during the operation and the general operation manual is confirmed based on the factor. This paper introduces the procedure for lifting operations by parallel Connected Floating Cranes using synchronized operation system, and its applications to lifting operation of a heavy cargo such as barge lifting test, floating dock installation and 900 ton goliath crane replacement operation, etc.

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