• Journal of the Society of Naval Architects of Korea
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• v.41 no.6
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• pp.114-119
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• 2004

For passenger vessels, twin shaft types in propulsion system is generally adopted to provide a high-speed performance in low draught due to restricted operating condition in harbors or water channels. Struts of twin open shaft type support the shafts, bearings, and propellers. Therefore, strut design is needed to consider not only hydrodynamic performance but also structural and noise/vibration performance, In this paper, considerations in strut design at the initial design stage have been discussed based on existing references, numerical calculations, and their comparisons. Also, the strut design of a RoPax ferry has been carried out at the initial design stage, for an example.

• Journal of the Korean Society of Marine Environment & Safety
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• v.8 no.1
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• pp.81-87
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• 2002

High speed naval ships are configured with open shafts The shafts, bearings, and propellers are supported by shaft struts. Proper design of struts involves issues of structural, vibration, and hydrodynamic analysis and design. Strut arm cavitation in high speed occurs because of a misalignment of the strut arm with the local incident flow. Proper selection of the strut section can minimize the generation of cavitation. This paper describes issues in the design struts and notices based on the design of Patrol Craft and Amphibious Ship.

• Tunnel and Underground Space
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• v.4 no.1
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• pp.63-76
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• 1994

This paper discusses contents of the existing design, the behaviours prediction on the strut and retaining wall around subsurfaces, and also evaluates the measured results in comparison with the management criterion during excavation period of ventilation shaft at Pusan-Subway 220. Field measurements showed that maximum displacement 23.74 mm at boundary site of multistratification and the weathered rock to be formed at 0.2~0.6 H of total excavating depth(H), 68 ton of maximum axial force and 4.4X102 kg/cm2 of stress on strut. The measured axial force exceeds prediction levels by up to 50 percent at the weathered soil & rock, and the others come under the category of their levels. The great gap of both field measurements and prediction on behaviour makes a difference of the site situation at the design stage and the practical working. This measured value is greatly safety in comparison with that of the safety criterion, but axial force at 4~5 strut of ventilation shaft l is higher than the prediction.

• Clinics in Shoulder and Elbow
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• v.20 no.2
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• pp.95-99
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• 2017

Background: The purpose of this study was to investigate the clinical and radiological outcomes of locking plate fixation with fibular strut allograft to manage unstable osteoporotic proximal humerus fractures. Methods: We retrospectively reviewed 15 patients who underwent open reduction and locking plate fixation with fibular strut allograft for osteoporotic proximal humerus fracture between July 2011 and June 2015. For functional evaluation, we evaluated visual analogue scale (VAS) pain score, American Shoulder and Elbow Surgeons (ASES) score, University of California Los Angeles (UCLA) shoulder score, and active range of motion. For radiological evaluation, shoulder true anteroposterior (AP) and AP in $20^{\circ}$ external rotation, as well as the axillary view were taken at two weeks, six weeks, three months, six months, and one year. And the neck-shaft angle was measured on the AP view in $20^{\circ}$ external rotation view. Results: At the one-year follow-up, mean VAS pain score and all shoulder scores, including ASES score and UCLA shoulder score, exhibited satisfactory clinical outcomes. All patients obtained bone union between three and six months post-procedure. Moreover, the mean immediate postoperative neck-shaft angle was $138^{\circ}{\pm}4^{\circ}$, and at one-year follow-up, the neck shaft angle was $137^{\circ}{\pm}5^{\circ}$. There was no significant difference between the preoperative and postoperative values (p=0.105). Conclusions: For the unstable two-part and three-part osteoporotic proximal humerus fractures with medial calcar comminution, the use of fibular strut allograft with locking plate fixation was effective in maintaining the initial status of reduction and exhibiting the satisfactory functional and radiological outcomes.

• Bulletin of the Society of Naval Architects of Korea
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• v.17 no.2
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• pp.49-53
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• 1980

• International Journal of Naval Architecture and Ocean Engineering
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• v.1 no.1
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• pp.50-56
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• 2009

The hydrodynamic effect of appendages for high-speed passenger vessels, such as Ro-Pax, Ro-Ro and cruiser vessels, is very severe and, therefore, it is essential to carry out the design of appendages for high-speed passenger vessels from the preliminary design stage to the final detail design stage through a full survey of the reference vessels together with sufficient technical investigation. Otherwise, many problems would be caused by mismatches between the appendages and the hull form. This paper investigates the design characteristics of some appendages, such as the side thruster, the shaft-strut, and the stern wedge, based on the design experience accumulated at Samsung, on CFD, and on model test results for high-speed passenger vessels. Further to this investigation, some practical and valuable design guidelines for such appendages are suggested.

• Clinics in Shoulder and Elbow
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• v.19 no.4
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• pp.216-222
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• 2016

Background: We investigated the effectiveness of fibular strut allograft augmentation of proximal humerus fractures to prevent varus deformity in patients over the age of 65 years with insufficient medial support. Methods: We analyzed the clinical and radiological outcomes of locking plate fixation with adjunct fibular strut allograft augmentation in 21 patients with proximal humeral fractures. The inclusion criteria were age (65-year-old or older); presence of severe medial comminution; inadequate medial support; and those who could participate in at least a one year follow-up. The average age was 76.4 years. We analyzed each patient's Constant score, our indicator of clinical outcome. As radiological parameters, we analyzed time-to-bone union; restoration of the medial hinge; difference between the immediately postoperative and the last follow-up humeral neck-shaft angles;; and anatomical reduction status, which was assessed using the Paavolainen method. Results: A successful bone union was achieved in all patients at an average of 11.4 weeks. We found that the average Constant score was 74.2, showing a satisfactory outcome. The average difference in the humeral neck-shaft angles between the immediately postoperative time-point and at the final follow-up was $3.09^{\circ}$. According to the Paavolainen method, the anatomical reduction was rated excellent. The medial hinge was restored in 14 of 21 patients. Although we did not find evidence for osteonecrosis, we found that a single patient had a postoperative complication of screw cut-out. Conclusions: Fibular strut allografting as an adjunct treatment of proximal humeral fractures may reduce varus deformity in patients with severe medial comminution.

• Clinics in Shoulder and Elbow
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• v.23 no.3
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• pp.152-155
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• 2020

Periprosthetic fracture after total elbow replacement surgery is a difficult complication to manage, especially when it comes together with implant loosening. If stem revision and internal fixation of the periprosthetic fracture are performed simultaneously, this would be a very challenging procedure. Most of total elbow replacement implants are cemented type. Cement usage at periprosthetic fracture site may interfere healing of fractured site. Authors underwent internal fixation with use of locking plate and cerclage wire for periprosthetic fracture, allogenous fibular strut bone inserted into the humerus intramedullary canal allowing the fractured site to be more stable without cement usage. At 10-month follow-up, the complete union and good clinical outcome was achieved. We present a novel technique for treating periprosthetic fracture with implant loosening after total elbow replacement surgery, using intramedullary allogenous fibula strut bone graft.

• Journal of Advanced Marine Engineering and Technology
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• v.10 no.4
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• pp.41-49
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• 1986

With the trend towards high propulsive level, increasing ship's dimensions and heavier shaft systems supported by the hull structure of relatively stiffness in modern ships, transverse vibrations of propulsion shaft system have become one of the problems that should be predicted in the early design stage. Regarding transverse vibrations, coupling terms such as oilfilm, gyroscope and hydrodynamic effect of the propeller exist between the vertical and horizontal vibration, furthermore for the shaft system with strut and bossing its physical properties incorporated with hull structure must be considered. In order to predict the transverse vibratory condition of the propulsion shaft and take some appropriate countermeasures, it is necessary to make a fairly strict estimation of the vibratory behaviours of it. In this paper, theoretical approach using the finite element method is investigated to calculate natural frequencies and vibration modes for coupled free transverse vibrations of shaft system in two planes. Based on the method investigated a digital computer program is developed and is applied to calculate the above-mentioned vibrations of an experimental model shaft system. The results of the calculation are compared with those of the experimental measurements and they show an acceptable agreement.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.468-471
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• 2022

The influence of the central axis and the strut supporting the helical ribbon was investigated in a helical ribbon impeller mixing tank through experiments and visualization. As a result, the strut, which is in the transverse direction, turned out to have a significant adverse effect on the mixing performance such as the occurrence of incomplete mixing region from the change of the liquid level. In contrast, the central axis, which in the longitudinal direction, did not show much adverse effects.