• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.209-212
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• 2006

Bond between reinforcing bar and surrounding concrete is supposed to transfer load safely in the process of design of reinforced concrete structures. The effects of defomation properties on bond of reinforcing bars to concrete are studied. Beam-end tests are used to investigate the effects of machining of bars in addition to rib angle and relative rib area. The test results show that bond strength of machined bars were higher than the conventional bars produced in factory. Higher rib height bars with rib angle $30^{\circ}{\sim}60^{\circ}$ showed higher bond strength than lower rib height bars with low angle.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.209-215
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• 2000

Precision forging technology that can control flow velocity of workpiece have been developed to minimize the amounts of machining. To get the uniform rib length, flow velocity distribution is needed to be estimated and controlled. Computer-aided design is known for very effective to estimate the deformation behavior and design the die for controlling the flow velocity. In this study, die design to control the deformation velocity are investigated using the DEFORM-2D about rib-web shape parts. Also we can get uniform rib length by enforcing the back pressure at end section of rib. The applied load of back pressure farming is lower than that of conventional forging. These results are analysed and confirmed by the experiment.

• Journal of the Korean GEO-environmental Society
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• v.24 no.10
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• pp.25-31
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• 2023

Wide tunnels,such as those with high filling, can suffer limited applicability and also reduced structural stability. Therefore, to improve these limitations of precast cut-and-cover tunnel segments, this study proposes rib reinforcement of the vaults of the precast segments. Large-sized experiments assess the effectiveness of the various rib-reinforced precast arch cut-and-cover tunnel structures, and compare them against otherwise similar non-rib-reinforced specimens. The results show that the rib-reinforced precast cut-and-cover segments are suitable for building wide tunnels with high filling.

• Journal of Chest Surgery
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• v.8 no.2
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• pp.159-168
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• 1975

We have experienced 61 cases of Clinically diagnosed tuberculous peripleural abscess which was surgically treated at St. Mary's Hospital of Catholic Medical College from Mar. 1963 to Feb. 1974. Out of them, 52 cases of pathologically confirmed tuberculous peripleural abscess were reviewed and its pathogenesis, treatment and so called "rib caries" were discussed. In the past, they have been described as a variety of the names, such as rib caries, cold abscess of the chest wall, pericostal abscess, lymphadenitis tuberculosa of the chest wall, chronic draining sinuses of the chest wall and other descriptive terms. Although it has been said that the tuberculous abscess on the chest wall developed as a secondary disease from so called "rib caries" but now it has been clear that this abscess occurred not from tuberculosis of the rib but from tuberculous lesion developed between end-othoracic fascia and parietal pleura usually following pulmonary tuberculosis and/or tuberculous pleurisy and the involvement of rib or ribs are secondary one from peripleural abscess, as we confirmed. Therefore we advocate that the nomination, rib caries, should not be used unless there is a primary tuberculous lesion on ribs. The results were as follows: 1. The highest age group of tuberculous peripleural abscess was ranged from the first to third decade (78%) 2. The location of tuberculous peripleural abscess on the chest wall were as follows, 31 cases on the anterior, 19 cases on lateral and 2 cases on the posterior. 3. On x-ray examination, abnormal findings including parenchymal tuberculous lesion and pleural changes were seen is 38 cases. 4. There was no destructive change of periosteum and rib in 23 cases of tuberculous peripleural abseess during operation. However the periosteal denudation and/or rib destruction were found in 29 cases. 5. The all cases of tuberculous peri pleural abscess developed from between endothoraclc fascia and parietal pleura, as we confirmed. With antituberculous therapy, operation should be radical by wide incision on the lesion including thorough curettage with proper drainage of Iiquified caseating materials and appropriate rib resection, if necessary.tion, if necessary.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.4
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• pp.20-25
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• 2010

An integrated Mach-Zehnder interferometric sensor operating at 632.8 nm was designed and fabricated by the technology of planar rib waveguides. Rib waveguide based on silica system ($SiO_2-SiO_xN_y-SiO_2$) was geometrically designed to have single mode operation and high sensitivity. It was structured by semiconductor fabrication processes such as thin film deposition, photolithography, and RIE (Reactive Ion Etching). With the power observation, propagation loss measurement by cut-back method showed about 4.82 dB/cm for rib waveguides. Additionally the chromium mask process for an etch stop was employed to solve the core damaging problem in patterning the sensing zone on the chip. Refractive index measurement of water/ethanol mixture with this device finally showed a sensitivity of about $\pi$/($4.04{\times}10^{-3}$).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.6
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• pp.734-743
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• 1999

The local Nusselt numbers have been measured for a round turbulent jet impinging on the concave surface with and without rib. Liquid crystal/transient method was used to determine the Nusselt number distributions along the surface. The temperature on the surface was measured using liquid crystal and a digital color image processing system. The experiments were made for the jet Reynolds number (Re) 23,000, the dimensionless nozzle-to-surface distance (L/d) from 4 to 10, the dimensionless surface curvature (d/D) 0.056, and the rib type (height ($d_1$) 0.2 cm, pitch (p) from 1.2 to 3.2 cm). It was founded that only when $L/d{\geq}6$, the average Nusselt numbers on the concave surface with rib are higher than those without rib, mainly due to an increase in the turbulent intensity caused by the effect of rib attached to the wall surface. It was realized that the rib attached to the concave surface may no longer enhance the heat transfer rate or even lowers it depending on the rib type and flow conditions. In addition, the results by the steady-state method using the gold-film Intrex were in good agreement with those by the transient shroud method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.138-147
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• 2011

The objective of this study which it sees direct shear stress and comparative analysis of flexural shear stress leads and it is a shear stress analysis which it follows in load direction of the structure which uses Perfobond Rib shear connectors. To analyze direct shear stress, five Perfobond Rib shear connect experiments were fabricated with five variables and conducted Push-out Tests. After experiments, mechanism of Perfobond Rib shear connector was examined and direct shear formula was proposed based on primary factors which influence direct shear stress. Also, for the analysis of flexural shear steel-concrete composite slab specimens were fabricated and static flexural test. Based on the static flexural test it analyzed the flexural behavior and the flexural shear stress it calculated. Direct shear stress and EN 1994-1-1 to lead and be calculated, it compared the flexural shear stress and it analyzed in about the shear resistance stress which it follows in load direction.

• Journal of Chest Surgery
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• v.54 no.1
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• pp.59-64
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• 2021

Background: Diaphragmatic injuries following blunt or penetrating thoraco-abdominal trauma are rare, but can be life-threatening. Rib fractures are the most common associated injury in patients with a traumatic diaphragmatic injury (TDI). We hypothesized that the pattern of rib fracture injuries could dictate the likelihood of acute TDIs. Methods: A retrospective study was carried out between April 2014 and October 2018 to analyze patients with TDIs and rib fractures at a major trauma center in London, United Kingdom. Results: Over the study period, 1,560 patients had rib fractures, of whom 14 had associated diaphragmatic injuries. Left-sided diaphragmatic injuries were found in 8 patients (57%). A significant proportion of the rib fractures were located posterolaterally (44.9%). The highest frequency of fractures was found in ribs 5-10, which accounted for 74% of all the fractures. Ten patients underwent surgery, of whom 7 were diagnosed with a diaphragmatic injury intraoperatively after video-assisted thoracoscopic surgery assessment of the pleural cavity. Two patients died due to severe injuries of other organs and the remaining 2 patients were managed conservatively. Conclusion: Our series of patients demonstrates a relationship between significant rib fractures and diaphragmatic injuries in trauma patients, and the diagnostic difficulties in identifying the condition. We found that the location of the rib fractures and the pattern of injury in patients with TDIs were much lower and posterolateral in the chest wall without a preference for laterality. We suggest using a thoracoscope in patients undergoing chest wall surgery post-trauma to aid in diagnosing this condition.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.3
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• pp.265-275
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• 2009

Due to the limitation of construction efficiency and structural safety, the application of the high covering and wide width tunnels was limited prior to the introduction of precast rut and cover tunnels. Therefore, a cut and cover tunnel structure with rib reinforcement is proposed to mechanically improve the safety on condition of high covering and wide width tunnel. Therefore, a technical problem that can provide a response similar to the actual filling conditions is analyzed by the finite element analyses, moreover, the mechanical behaviour of developed rib-reinforced precast tunnel liner through a large-sized model test will be investigated. The ultimate load of the developed rib-reinforced precast tunnel liner shows a 3% reduction compared to existing rib-reinforced precast tunnel liner, especially, the section of rib-reinforcement decreased to 55% compared to it of existing. Therefore, the stability of tunnel structure can be significantly improved through the developed rib-reinforced precast segment.

• Journal of Chest Surgery
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• v.56 no.2
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• pp.120-125
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• 2023

Background: Multiple rib fractures are common in blunt chest trauma. Until recently, most surgical rib fixations for multiple rib fractures were performed via open thoracotomy. However, due to the invasive nature of tissue dissection and the resulting large wound, an alternative endoscopic approach has emerged that minimizes the postoperative complications caused by the manipulation of injured tissue and lung during an open thoracotomy. Methods: Our study concentrated on patients with multiple rib fractures who underwent surgical stabilization of rib fractures (SSRF) between June 2018 and May 2020. We found 27 patients who underwent SSRF using video-assisted thoracoscopic surgery. The study design was a retrospective review of the patients' charts and surgical records. Results: No intraoperative events or procedure-related deaths occurred. Implant-related irritation occurred in 4 patients, and 1 death resulted from concomitant trauma. The average hospital stay was 30.2±20.1 days, and ventilators were used for 12 of the 22 patients admitted to the intensive care unit. None of the patients experienced major pulmonary complications such as pneumonia or acute respiratory distress syndrome. Conclusion: Minimally invasive rib stabilization surgery with the assistance of a thoracoscope is expected to become more widely used in patients with multiple rib fractures. This method will also assist patients in a quick recovery.