• Title/Summary/Keyword: U-rib

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Research on the longitudinal stress distribution in steel box girder with large cantilever

  • HONG, Yu;LI, ShengYu;WU, Yining;XU, Dailing;PU, QianHui
    • Steel and Composite Structures
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    • v.44 no.5
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    • pp.619-632
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    • 2022
  • There are numerous structural details (Longitudinal beam, web plate, U-ribs and I-ribs) in the top and bottom plates of steel box girders, which have significant influences on the longitudinal stress (normal stress) distribution. Clarifying the influence of these structural details on the normal stress distribution is important. In this paper, the ultra-wide steel box girder with large cantilevers of the Jinhai Bridge in China, which is the widest cable-stayed bridge in the world, has been analyzed. A 1:4.5 scale laboratory model of the steel box girder has been manufactured, and the influence of structural details on the normal stress distribution in the top and bottom plates for four different load cases has been analyzed in detail. Furthermore, a three-dimensional finite element model has been established to further investigate the influence regularity of structural details on the normal stress. The experimental and finite element analysis (FEA) results have shown that different structural details of the top and bottom plates have varying effects on the normal stress distribution. Notably, the U-ribs and I-ribs of the top and bottom plates introduce periodicity to the normal stress distribution. The period of the influence of U-ribs on the normal stress distribution is the sum of the single U-rib width and the U-rib spacing, and that of the influence of I-ribs on the normal stress distribution is equal to the spacing of the I-ribs. Furthermore, the same structural details but located at different positions, will have a different effect on the normal stress distribution.

Fatigue property analysis of U rib-to-crossbeam connections under heavy traffic vehicle load considering in-plane shear stress

  • Yang, Haibo;Qian, Hongliang;Wang, Ping
    • Steel and Composite Structures
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    • v.38 no.3
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    • pp.271-280
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    • 2021
  • In this study, the fatigue property of U rib-to-crossbeam connections in orthotropic steel bridge (OSB) crossbeams under heavy traffic vehicle load was investigated considering the effects of in-plane shear stress. The applicability of an improved structural stress (ISS) method was validated for the fatigue behavior analysis of nonwelded arc-shaped cutout regions in multiaxial stress states. Various types of fatigue testing specimens were compared for investigating the equivalent structural stress, fatigue crack initiation positions, and failure modes with the unified standards. Furthermore, the implications of OSB crossbeams and specified loading cases are discussed with respect to the improved method. The ISS method is proven to be applicable for analyzing the fatigue property of nonwelded arc-shaped cutout regions in OSB crossbeams. The used method is essential for gaining a reliable prediction of the most likely failure modes under a specific heavy traffic vehicle load. The evaluated results using the used method are proven to be accurate with a slighter standard deviation. We obtained the trend of equivalent structural stress in arc-shaped cutout regions and validated the crack initiation positions and propagation directions by comparing them with the fatigue testing results. The implications of crossbeam spans on fatigue property are less significant than the effects of crossbeams.

Minimization of Warpage in Injection-molded Parts By Optimal Design of U-type Ribs (U자형 리브의 최적설계에 의한 사출제품의 휨 최소화)

  • Park, Jong-Cheon;Kim, Kwang-Ho;Kim, Kyung-Mo;Koo, Bon-Heung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.7 no.1
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    • pp.53-61
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    • 2008
  • In this research, the layout and geometry of U-type ribs in the part, including significant process conditions, are automatically optimized to reduce part warpage with robustness in consideration. The optimization procedure are based on an iterative redesign methodology integrated with computer aided injection molding simulation, Taguchi's Design of Experiment(DOE), and a direct search-based optimization method. The robustness of a design alternative is efficiently measured by introducing composite noise factor and Taguchi's signal-to-noise ratio. As a solution search methodology, the modified design space reduction method based on orthogonal arrays is employed to exploit an optimal robust design alternative. To illustrate the proposed methodology, a case study is performed on simulation results, where an optimal robust design alternative is obtained with a moderate number of iterations.

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Treatment of Multiple Rib Fracture and Flail Chest with Judet's Strut-105 Case REport- (다발성 늑골골절 및 Flail Chest 환자에서 Judet's strut를 이용한 수술적 고정술 105례)

  • Park, Byeong-Sun;Jo, Wan-Jae;O, Jeong-U
    • Journal of Chest Surgery
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    • v.30 no.8
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    • pp.803-808
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    • 1997
  • There were 105 patients with multiple rib fracture or flail chest who had underwent surgical rib fixation using judet's strut from Aug. 1989 to Aug. 1995. They were 86 men and 19 women, and the age distribution was from 17 to 77(mean $48\pm12).$ The most common cause of accident was a traffic accident(81%), The mean number of rib fracture was 5.5 and the distribution of patient were flail chest(72, 64.7%), severe displaced rib Fracture(18, 17.1%), traumatic chest wall deformity(10, 95%) and others(5, 4.7%). The operative mortality was 1 patient(0.96%) and the incidence of postoperative complication were 13 patients(12.3%). The duration of perioperative artificial ventilator therapy was $90.5\pm22.6$ hours. Our method allowed shorter duration of an artificial ventiatin and decreased a functional sequelae. We find this technique to be better than previously published methods, since it provides better stabilization and immobilization of he ribs and thus obviates the need for artificial ventilation and prevents post-traumatic chest deformity.

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The Applicability Study of U-Channel Bridge (U-Channel Brdige의 적용성 연구)

  • Choi, Dong-Ho;Lee, Joo-Ho;Park, Myoung-Gyun;Kim, Sung-Jae;Kim, Yong-Sik;Kim, Sung-Won
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.495-498
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    • 2008
  • In this paper applicable range of U-Channel Bridge (UCB) that has recently been introduced as a new bridge type was studied. For structural analysis models used with the frame and plate elements was proposed, and verification of the models were performed. Using these structural models structural analysis of models with span length of 20m-45m and inner width of 5m-13m were performed. As a result for U-shape sections were applicable in the range of 20m span and 35m span, slab was applicable in the range of 5m inner width and 12m inner width. To increase applicable range of UCB H-shape sections and slab with rib were proposed. As a result UCB were applicable in the range of 20m span and 45m span, in the range of 5m inner width and 13m inner width.

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Rib Segmentation via Biaxial Slicing and 3D Reconstruction (다중 축 슬라이싱 및 3 차원 재구성을 통한 갈비뼈 세그멘테이션)

  • Hyunsung Kim;Gyurin Byun;Seonghyeon Ko;Junghyun Bum;Duc-Tai Le;Hyunseung Choo
    • Proceedings of the Korea Information Processing Society Conference
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    • 2023.11a
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    • pp.611-614
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    • 2023
  • 갈비뼈 병변 진단 과정은 방사선 전문의가 CT 스캐너를 통해 생성된 2 차원 CT 이미지들을 해석하며 진행된다. 병변의 위치를 파악하고 정확한 진단을 내리기 위해 수백장의 2차원 CT 이미지들이 세밀하게 검토되며 갈비뼈를 분류한다. 본 연구는 이런 노동 집약적 작업의 문제점을 개선시키기 위해 Biaxial Rib Segmentation(BARS)을 제안한다. BARS 는 흉부 CT 볼륨의 관상면과 수평면으로 구성된 2 차원 이미지들을 U-Net 모델에 학습한다. 모델이 산출한 세그멘테이션 마스크들의 조합은 서로 다른 평면의 공간 정보를 보완하며 3 차원 갈비뼈 볼륨을 재건한다. BARS 의 성능은 DSC, Recall, Precision 지표를 사용해 평가하며, DSC 90.29%, Recall 89.74%, Precision 90.72%를 보인다. 향후에는 이를 기반으로 순차적 갈비뼈 레이블링 연구를 진행할 계획이다.

Tumor Regression Effect of Allergen-removed Rhus Verniciflua Stokes based Traditional Korean Medicine on a Patient with Metastatic Papillary Thyroid Carcinoma : Single Case Report (전이성 유두상 갑상선암 환자를 대상으로 투여한 알러젠 제거 옻나무 추출물의 종양 소퇴 1례)

  • Lee, Jin-Soo;Jerng, Ui-Min;Jeong, Jong-Soo;Park, Jae-Woo;Jung, Hyun-Sik;Yoon, Seong-Woo
    • The Journal of Internal Korean Medicine
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    • v.29 no.3
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    • pp.827-834
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    • 2008
  • Papillary thyroid carcinoma is the most common type of thyroid malignancy. It has better prognosis and rarer incidence of distant metastasis than other types of thyroid malignancy. However, once distant metastasis happens, its result will be bad. They mostly spread to the lungs and bones. and rarely to the brain. We report a patient with a papillary thyroid carcinoma metastasis to the lymph nodes. the ribs. the brain, and the lungs. The patient underwent total thyroidectomy, radioiodine ablation, rib partial resection, and lung wedge resection. However, upon progress of metastasis. the patient insisted on being treated with traditional Korean medical treatment using allergen-removed Rhus Verniciflua Stokes (A-RVS) instead of the conventional treatment including chemotherapy. The size of the tumor partly decreased, and the patient showed no side effects. This case report brings forth the importance of a thorough study in papillary thyroid carcinomas and their metastasis from the traditional Korean medical point of view, along with the long-term effect of allergen-removed Rhus Verniciflua Stokes (A-RVS).

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Study on Dai Meridian(帶脈) and Meridian Points(經穴) of Joining with Circulation of Dai Meridian through Literatures of Every Generation (대맥(帶脈) 및 그 유주상(流注上) 회합(會合)하는 경혈(經穴)에 대한 문헌적(文獻的) 고찰(考察))

  • Yang Seung-Joung;Jin Cheon-Sik;Cho Myung-Rae
    • Korean Journal of Acupuncture
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    • v.18 no.1
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    • pp.105-116
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    • 2001
  • We examined and referred to some literatures on the meaning, Dai meridian and Meridian points of joining with circulation of Dai meridian through literatures of every generation. And then we came to get a few conclusions as follows. 1. Dai meridian starts below the hypochondriac region. Running obliquely downward, it runs transversely around the waist like a belt. Its function is to bind up all the meridians to circulate in a proper way. 2. The coalescent points of dai meridian are $D\grave{a}im\grave{a}i$(帶脈), $W\check{u}sh\bar{u}$(五樞) and $W\acute{e}id\grave{a}o$(維道). 3. Location of $D\grave{a}im\grave{a}i$(帶脈) is on the lateral side of the abdomen, 1.8 cun below $Zh\bar{a}ngm\grave{e}n$(章門), at the crossing point of vertical line through the free end of the 11th rib and a horizontal line through the umbilicus. Location of $W\check{u}sh\bar{u}$(五樞) is on the lateral side of the abdomen, anterior to the anterosuperior iliac spine, 3 cun below the level of the umbilicus. Location of $W\acute{e}id\grave{a}o$(維道) is on the lateral side of the abdomen, anterior and inferior to the anterosuperior iliac spine, 0.5 cun anterior and inferior to $W\check{u}sh\bar{u}$(五樞). 4. Indication of $D\grave{a}im\grave{a}i$(帶脈) is irregular menstruation, leukorrhea with reddish discharge, hernia, pain in the lumbar and hypochondriac region. Indication of $W\check{u}sh\bar{u}$(五樞) is prolapse of the uterus, leukorrhea with reddish discharge, irregular menstruation, hernia, pain in the lower abdomen, constipation and lumbosacral pain. Indication of $W\acute{e}id\grave{a}o$(維道) is edema, pain in the side of the lower abdomen, prolapse of the uterus, hernia and morbid leukorrhea. 5. The Dai meridian binds all meridians, produces pregnancy, grasps lumbar and abdomen region and controls leukorrhea. 6. Diseases of the Dai meridian manifested as distention and fullness in the lumbar region and abdomen, leukorrhea with reddish discharge, pain the navel, lumbar and spinal regions, flaccidity and hypoactivity of the lower limbs, etc.

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Evaluation of Machining Characteristics of the Micro Grooving for the Mold of PDP Barrier Rib (PDP 격벽 금형 미세 홈 가공 특성 평가)

  • 이은상;김남훈;이득우;김남경;김덕환
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.12 no.4
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    • pp.23-28
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    • 2003
  • This paper describes the machining characteristics of a developed micro grooving machine. Experiments have been conducted on the various grooving condition such as spindle revolution speed, feed rate and depth of groove. V and U-shaped blade tool and STD11 workpiece was used in this study. To evaluate the developed micro grooving machine, AE signal obtained from each experimental condition was analyzed, and cutting stability was compared with the surface state. As a result this study presented the process to optimize grooving condition and possibility of application of AE technique in groove machining.

A study on the machining characteristics of the micro grooving for the mold of PDP barrier rib (PDP 격벽 금형의 Micro Grooving 가공 특성에 관한 연구)

  • 이은상;김남훈;이득우;김남경
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.542-546
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    • 2003
  • This paper describes the machining characteristics of a developed micro grooving machine. Experiments have been conducted on the various grooving condition such as spindle revolution speed, feed rates and depth of groove. V and U-shaped blade tool and STD11 workpiece was used in this study. Evaluating the machining conditions, RMS and frequency spectrum analysis of AE(acoustic emission) signals according to each conditions were applied. As a result, this study presented the process to optimize micro grooving condition and possibility of application of AE technique in groove machining.

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