• Journal of the Earthquake Engineering Society of Korea
• /
• v.22 no.1
• /
• pp.23-32
• /
• 2018

In this study, we conducted a shake table test to verify the seismic performance of the paneling system with steel truss composed of bolt connections. The control group was set to the traditional paneling system with steel truss connected by spot welding method. Test results showed that the bolted connection type paneling system has excellent deformation capacity without cracking or brittle fracture of the steel truss connection parts compared to the welding type paneling system. Furthermore, in the bolted connection type, slight damage occurred at the time of occurrence of the same story drift angle as compared with the existing method, it is considered that it has excellent seismic performance. In compliance with the performance-based design recommended for the current code (ASCE 41-13) on non-structural components, it is judged that in the case of the bolted connection type paneling system, it can be applied to all risk category structures without restriction. However, in the case of traditional paneling system with spot welding method, it is considered that it can be applied limitedly.

• The Journal of Advanced Prosthodontics
• /
• v.10 no.5
• /
• pp.388-394
• /
• 2018

PURPOSE. To measure axial displacement of different implant-abutment connection types and materials during screw tightening at the recommended torque by using a contact scanner for two-dimensional (2D) and three-dimensional (3D) analyses. MATERIALS AND METHODS. Twenty models of missing mandibular left second premolars were 3D-printed and implant fixtures were placed at the same position by using a surgical guide. External and internal fixtures were used. Three implant-abutment internal connection (INT) types and one implant-abutment external connection (EXT) type were prepared. Two of the INT types used titanium abutment and zirconia abutment; the other INT type was a customized abutment, fabricated by using a computer-controlled milling machine. The EXT type used titanium abutment. Screws were tightened at $10N{\cdot}cm$, simulating hand tightening, and then at the manufacturers' recommended torque ($30N{\cdot}cm$) 10 min later. Abutments and adjacent teeth were subsequently scanned with a contact scanner for 2D and 3D analyses using a 3D inspection software. RESULTS. Significant differences were observed in axial displacement according to the type of implant-abutment connection (P<.001). Vertical displacement of abutments was greater than overall displacement, and significant differences in vertical and overall displacement were observed among the four connection types (P<.05). CONCLUSION. Displacement according to connection type and material should be considered in choosing an implant abutment. When adjusting a prosthesis, tightening the screw at the manufacturers' recommended torque is advisable, rather than the level of hand tightening.

• Journal of Korean Association for Spatial Structures
• /
• v.20 no.3
• /
• pp.27-34
• /
• 2020

This paper examines the seismic performance and structural design of the ceiling bracket-type modular connection. The bracket-type system reduces the cross-sectional area loss of members and combines units using fitting steel plate, and it has been developed to be fit for medium-story and higher-story buildings. In particular, this study conducted the cyclic loading test for the performance of the C-type and L-type brackets, and compared the results. The test results were also compared with the commercial FEA program. In addition, the structural design process for the bracket-type modular connection was presented. The two connections, proposed as a result of the test results, were all found to secure the seismic performance level of the special moment steel frame. In the case of initial stiffness, the L-type bracket connection was found to be great, but in the case of the maximum moment or fully plastic moment, it was different depending on the loading direction.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.20 no.1
• /
• pp.45-55
• /
• 2014

Purpose: The purpose of this study is to provide data on the basis for architectural planning of floor plan type and spatial composition by analysing standard mental health centers in Seoul. Methods: Data were collected through literature research, field surveys, and expert interviews to 22 standard mental health centers in Seoul. Results: The results of this study could be summarized as follows; Firstly, Mental Health Center is divided into five types according to the location. Location types of mental health center were 'Director type', 'Health center connection type', 'Public facilities connection type', 'Complex center connection type' and 'Commercial Facilities connection type'. Secondly, Depending on the type of management a mental health center is divided into two types. Types are 'Complex type' and 'Independent type'. Average area of 'Complex type' is $192.99m^2$ and 'Independent type' is $266.87m^2$. This difference affects the various spaces. Implications: It is necessary to give and architectural suggestion of mental health center in response to the proposal of the system.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2011.11a
• /
• pp.171-172
• /
• 2011

Green column and green beam, key structural members of green frame, have the characteristics of post-lintel structure, thanks to the steel frame in the connection, enabling prompt and precise installation. The connection of green frame can be divided into 4 types, depending on its shape, and each type is associated with different characteristics and construction methods. Notably, as the connection between green columns have differing types and sequences of work, subject to the connection method in use, a connection method optimized for relevant site conditions need to be selected. Therefore, this study analyzed pros and cons of 4 different types of green frame connection methods. The results set forth herein will provide basic data for subsequent studies to comparatively analyze the performance and constructibility of different green frame connection methods.

• The Korean Journal of Mycology
• /
• v.15 no.4
• /
• pp.250-253
• /
• 1987

The transfer of the isolated nuclei from P. florida into protoplasts of P. ostreatus was induced with polyethylene glycol and $CaCl_2$. Three types of transfer products of nuclei were obtained when transferred to MMM. Type 1 colonies were more vigrously growing mycelium and stable on MCM. One of the type 1 colonies, appeared segregation on MCM plus benomyl. The mycelium did not form clamp connection. These results suggest that type 1 colonies were nuclear hybrids or allodiploids. Type 2 was main products of nuclear transfer. The mycelium formed clamp connection and fertile on sawdust media. Type 3 was very slow growing or non-viable colonies after debris of nuclei or chromosomes transfer into recipient protoplasts. Isozyme pattern of esterase in type 1 produced a new band. Type 2 and type 3 could be characterized by parental bands.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.57 no.2
• /
• pp.198-201
• /
• 2008

We investigated the operating characteristics of the flux-lock type superconducting fault current limiter(SFCL) with the parallel connection between the primary and secondary windings which are connected with two superconducting units in series. The parallel connection for current level increase of the flux-lock type SFCL is necessary to apply the SFCL into the power system. The resistance generated in superconducting units was dependent upon the winding direction of the primary and the secondary coils, which can reduce the power burden. The resistance of the superconducting elements in the subtractive polarity winding is higher than that of the additive polarity winding. The fault current limiting effect of the subtractive polarity winding is better than that of the additive polarity winding. From this results, we confirmed that the power capacity of the flux-lock type SFCL could be increased by the parallel connection of the superconducting units.

• Journal of Bio-Environment Control
• /
• v.29 no.4
• /
• pp.473-479
• /
• 2020

In this study, the structural experiment was conducted with two types of specimens to investigate the mechanical behavior of the column-rafter-purlin connection of an arch-type greenhouse under monotonic loading. Based on the experimental results, the flexural performance was analyzed for two types of connections, and connection classification was attempted. Type B showed 77% of flexural performance compared to Type A, and both types showed that the rigidity and flexural strength did not reach the level of the full rigid. The behavior of the column-rafter-purlin connection was dominated by local buckling due to deformation of the weld and fasteners. As a result of connection classification by AISC standard, both Type A and B connections showed a result that did not meet the rigid connection performance assumed during design, and were classified as simple connection. Therefore, the connection performance evaluation and classification results show that the greenhouse design should be made in consideration of connection performance and in order to design a reliable greenhouse structure, a study on establishing clear design standards for the greenhouse connection is necessary.

• Kyungpook Mathematical Journal
• /
• v.55 no.3
• /
• pp.731-739
• /
• 2015

The object of the present paper is to characterize a Riemannian manifold admitting a type of semi-symmetric non-metric connection.

• Honam Mathematical Journal
• /
• v.46 no.1
• /
• pp.114-119
• /
• 2024

In this article, we consider a connection of vectorial type in some sense which is not a metric connection. We will then discuss when this connection $\tilde{\nabla}^*$ has parallel torsion T, that is, $\tilde{\nabla}^*T=0$.