• Structural Engineering and Mechanics
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• v.54 no.5
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• pp.999-1016
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• 2015

In this paper, we introduce a new method for assembly of shipbuilding blocks at sea and present its feasibility focusing on structural safety. The core concept of this method is to assemble ship building blocks by use of bolting, gluing and welding techniques at sea without dock facilities. Due to its independence of dock facilities, shipyard construction capability could be increased considerably by the proposed method. To show the structural safety of this method, a bulk carrier and an oil tanker were employed, and we investigated the structural behavior of those ships to which the new block assembly method was applied. The ship hull models attached with connective parts are analyzed in detail through finite element analyses, and the cargo capacity of the bulk carrier is briefly discussed as well. The results of these studies show the potential for applying this new block assembly method to practical shipbuilding.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.213-223
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• 2008

The instability of rock slopes caused by heavy rainfall and soil mass sliding needs the preventable and reinforcing method. The most important factor for the stability is the shear strength available in the planar part of the failure surface, which shows that a progressive failure takes place and a reinforcing of rock slope using FRP grout is effectively available. In this study, a grouting bolting interval predictions by limit equilibrium analysis and Matlab mathematical computer codes in several cases is presented for FRP reinforced rock slope. The proposed mathematical computer code can be easily applied for seeking properly FRP grout intervals prior to design and execute a reinforcement of a rock slope in practice.

• Proceedings of the Korean Reliability Society Conference
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• 2006.05a
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• pp.357-361
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• 2006

Fatigue fracture behavior of a hybrid joint part with bolting was evaluated in comparison to the case of static fracture. Hybrid joint part specimens for bending test were made with layers of CFRP and aluminum honeycomb. Characteristic fracture behaviors of those specimens were obviously different under static and cyclic loads. Static bending load showed the shear deformation at the honeycomb core, whereas cyclic bending load caused the delamination between CFRP skin layers and honeycomb core. Experimental results obtained by static and fatigue tests were considered in modifications of design parameters of the hybrid joint.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.13.1-13
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• 1983

Sudden esophageal obstruction by a bolus of food is not a rare phenomenon. The individual is frequently elderly and has ill-fitting dentures through others may initiate this by bolting food. In adult patient there is a frequent history of alcoholic intake, the consumption of meat with improper chewing. A common anatomic abnormality leading to meat impaction of the esophagus is hiatal hernia, which is often associated with a ring or stricture. Recently authors experienced a case of repeated esophageal foreign bodies in 10 days in the patient who had esophageal stricture.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.177-184
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• 2001

In this study, three most distinct types of general rigid connections are included in the modelling, with is implemented into a computer code. The cost, functions of connections are constructed by using the estimated unit cost of bolting, welding and connection-steel elements incorporating all the effect of materials, labor, and fabrication work. Bused on the recent developments of the reliability-based structural analysis and design as well as the extending knowledge on the probabilistic characteristics of load and resistances, the probability based design criteria have been successfully developed for many standards. Since the probabilistic characteristics depend highly on the local load and resistances, it is recognized to develop the design criterion compatible with domestic requirements. The existing optimum design methods, which are generally based on the structural theory and certain engineering experience, do not realistically consider the uncertainties of load and resistances and the basic reliability concepts.

• Journal of the Korea Institute of Building Construction
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• v.6 no.4 s.22
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• pp.77-83
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• 2006

The purpose of this study is to measure the straightness of prefounded columns during underground construction stages. There are several causes of an error of prefounded column: (1) columns connected by welding or bolting, (2) by placement of concrete and aggregates around columns, (3) movement during construction, and (4) load applied during construction. The error of column straightness is different for each column, and the tilting of columns is shown in one or two directions between floors. The additional loads caused by the error of straightness may give damage to buildings. This paper presents the measurement results of column straightness, and thus providing a basis for further analysis.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.20-26
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• 2007

The new integrated CAD-CAM systems induce an increasing demand for simulation tools, which are able to simulate industrial part assembly processes by welding, gluing, riveting or bolting(more generally by fastening). Concerning fastened flexible parts, there exist no efficient computational aid on tolerance and methodology available on the field. The first part briefly presents the approach method based on the finite element method for TADA(Tolerance Analysis of Deformable Assemblies). The second part compares the results obtained by simulation using the commercial FEM code with the measurements. The principal elements of dispersion have been identified and studied on an experimental basis in order to test the robustness of the TADA model. This has enabled us to verify the model's possibilities as regards industrial constraints such as the use of incompatible meshes or the use of triangular elements and so on.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.15-19
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• 2009

As robotic technologies have become more actively utilized to automate many construction tasks, they have been able to improve the construction productivity, quality, and workers safety on site. A new system, of which Robot-based Construction Automation (RCA), is currently being developed, and RCA systems consist of Construction Factory(CF), Automated Bolting Robots, and Climbing Hydraulic Robot. Especially. Climbing Hydraulic robot system is very important to RCA systems because of function as lifting the Construction Factory. In this paper, We validate safety of Climbing Hydraulic Robot system before application for real building construction.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.9
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• pp.40-51
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• 1995

The assemblability was determined by the structure of product and the relationship between composing parts and machining parts. In this paper, the bolt was divided into bolt-head, -shaft, -thread and -end. For the better assemblability in bolting process, the geometric and technological characteristics of bolts in terms of pre- and in-assembly process were analyzed. And this paper presents assemblability evaluation for bolt feature design alternatives. For this evaluation system, we considered systematically eight factors for assemblability, but introduced two factores for the stability of laying and for the handlability of parts. And AutoCAC system is interfaced with the evaluation system written in C-language.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.627-631
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• 2010

A new cultivar of lettuce (Lactuca sativa L.) with wrinkled traverse elliptic and deep red leaf, 'Chunpungjeokchukmyeon' which has late bolting and deep red expression leaf color was developed from a cross between 'Pojabijeokchukmyeon' (red leaf color and late bolting) and 'Meokchima' (Deep red and low yield). The cross and selection for advanced lines had been done by the pedigree method during 2000-2007. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon-do, Gyeonggi-do, Chungcheongbuk-do, Jeollabuk-do, Gyeongnam-do, and Jeju-do) from 2008 to 2009. The 'Chunpungjeokchukmyeon' has gray seed color and traverse elliptic leaves. The type of matured stage is medium shape between 'chukmyeon' and 'chima' leaf lettuce. Compared to 'Dukseomjeokchukmyeon', marketable yield of 'Chunpungjeokchukmyeon' was higher by 6% (at 372 g per plant) and 'Chunpungjeokchukmyeon' has particularly improved expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of 'Chunpungjeokchukmyeon' was three weeks longer than 'Dukseomjeokchukmyeon' at 4$^{\circ}C$. The anthocyanin content of 'Chunpungjeokchukmyeon' was higher than that of 'Dukseomjeokchukmyeon' with 17.5 mg/100g. The BSL (latucin+8-deoxylactucin+lactucopicrin) content of 'Chunpungjeokchukmyeon' is lower than that of 'Dukseomjeokchukmyeon'. Furthermore, its taste is better, more crispy, and sweeter than those of 'Dukseomjeokchukmyeon'. So we recommend that new cultivar 'Chunpungjeokchukmyeon' can be suitable for cultivation in spring season than summer season.