• Structural Engineering and Mechanics
• /
• v.24 no.4
• /
• pp.463-478
• /
• 2006

The design of structural frameworks for buildings is constantly evolving and is dependent on regional issues such as loading and constructability. One of the most promising recent developments for low to medium rise construction in terms of efficiency of construction, robustness and aesthetic appearance utilises concrete-filled steel tubular sections as the columns in a moment-resisting frame. These are coupled to rigid or semi-rigid connections to composite steel-concrete beams. This paper includes the results of a pilot experimental programme leading towards the development of economical, reliable connections that are easily constructed for this type of frame. The connections must provide the requisite strength, stiffness and ductility to suit gravity loading conditions as well as gravity combined with the governing lateral wind or earthquake loading. The aim is to develop connections that are stiffer, less expensive and easier to construct than those in current use. A proposed fabricated T-stub connection is to be used to connect the beam flanges and the column. These T-stubs are connected to the column using "blind bolts" with extensions, allowing installation from the outside of the tube. In general, the use of the extensions results in a dramatic increase in the strength and stiffness of the T-stub to column connection in tension, since the load is shared between membrane action in the tube wall and the anchorage of the bolts through the extensions into the concrete.

• Journal of the Korean housing association
• /
• v.18 no.2
• /
• pp.65-74
• /
• 2007

The study analyzes the remodeling characteristics of the four different types of secondary kitchens in apartment house based on their floor plans. The secondary kitchens are categorized into side placement, back placement, back placement with extensions on both sides, and back placement with an extension on a single side. The twelve apartment complexes in Ulsan were selected so that they may all consist each of the four types, and answered the survey. The classified traits of secondary kitchen were examined based on the characteristics of floor plan and remodeling. Side placement and back placement with extensions on both sides mostly used glass hinged doors. Back placement and back placement with a single side extension used glass sliding doors. It was found that the majority of the floor materials consisted of both wood and tiles, except for side placements, where only tiles were used. The sizes of the back placements with both and single side extensions were the largest. The side and back placements were rarely renovated, however, back placements with both and single side extensions went through massive remodeling.

• Journal of Advanced Navigation Technology
• /
• v.13 no.4
• /
• pp.600-609
• /
• 2009

We provide indifferentiable security analyses of pfMD, MDP, WPH, EMD, NI and CS hash domain extensions and their truncated versions. Unlike previous analytic techniques, the analytic technique considered in this paper is simple and easy. Moreover, the analytic technique can be generally applied to any types of hash domain extensions. That means that the technique can be used as an analyzing tool for any new developed hash function.

• Bulletin of the Korean Mathematical Society
• /
• v.32 no.2
• /
• pp.251-257
• /
• 1995

In the catagory of t-modules the Carlitz module C plays the role of $G_m$ in the category of group schemes. For a finite t-module G which corresponds to a finite group scheme, Taguchi [T] showed that Hom (G, C) is the "right" dual in the category of finite- t-modules which corresponds to the Cartier dual of a finite group scheme. In this paper we show that for Drinfeld modules (i.e., t-modules of dimension 1) of rank 2 there is a natural way of defining its dual by using the extension of drinfeld module by the Carlitz module which is in the same vein as defining the dual of an abelian varietiey by its $G_m$-extensions. Our results suggest that the extensions are the right objects to define the dual of arbitrary t-modules.t-modules.

• Journal of the Korean Mathematical Society
• /
• v.45 no.6
• /
• pp.1785-1801
• /
• 2008

Noncommutative extensions of the Gross and Beltrami Laplacians, called the quantum Gross Laplacian and the quantum Beltrami Laplacian, resp., are introduced and their basic properties are studied. As noncommutative extensions of the Fourier-Gauss and Fourier-Mehler transforms, we introduce the quantum Fourier-Gauss and quantum Fourier- Mehler transforms. The infinitesimal generators of all differentiable one parameter groups induced by the quantum Fourier-Gauss transform are linear combinations of the quantum Gross Laplacian and quantum Beltrami Laplacian. A characterization of the quantum Fourier-Mehler transform is studied.

• Bulletin of the Korean Mathematical Society
• /
• v.50 no.5
• /
• pp.1711-1723
• /
• 2013

P. V$\acute{a}$mos called a ring R 2-good if every element is the sum of two units. The ring of all $n{\times}n$ matrices over an elementary divisor ring is 2-good. A (right) self-injective von Neumann regular ring is 2-good provided it has no 2-torsion. Some of the earlier results known to us about 2-good rings (although nobody so called at those times) were due to Ehrlich, Henriksen, Fisher, Snider, Rapharl and Badawi. We continue in this paper the study of 2-good rings by several authors. We give some examples of 2-good rings and their related properties. In particular, it is shown that if R is an exchange ring with Artinian primitive factors and 2 is a unit in R, then R is 2-good. We also investigate various kinds of extensions of 2-good rings, including the polynomial extension, Nagata extension and Dorroh extension.

• International Journal of Human Ecology
• /
• v.4 no.1
• /
• pp.1-14
• /
• 2003

This study examines apparel brand extensions in terms of types and leverage effects. The researchers identified types of apparel brand extensions based on recent data gathered from the Korean apparel market. Three hundred forty eight Korean female subjects in their 20's evaluated three hypothetically extended brands from a major casual brand which actually exists in the Korean market. Major findings of the study follow. First, apparel brands are extended to different product categories by adjusting mostly target profiles as well as product usage, product class, and distribution channel. Secondly, leverage effects, the extent of image transfer from the parent brand to extended brands, are different according to the extension types.

• Korean Journal of Logic
• /
• v.9 no.1
• /
• pp.1-29
• /
• 2006

This paper investigates algebraic semantics for sKD and its extensions $sKD_\triangle$, $sKD\forall$, and $sKD\forall{_\triangle}$: sKD is a variant of the infinite -valued Kleene- Diense logic KD; $sKD_\triangle$ is the sKD with the Baaz's projection A; and $sKD\forall$ and $sKD\forall{_\triangle}$: are the first order extensions of sKD and $sKD_\triangle$, respectively. I first provide algebraic completeness for each of sKD and $sKD_\triangle$. Next I show that each $sKD\forall$ and $sKD\forall{_\triangle}$: is algebraically complete.

• Proceedings of the KACD Conference
• /
• 2003.11a
• /
• pp.579-579
• /
• 2003

I. Objectives The aim of this study was to evaluate and compare the effectiveness of sealer placement in simulated root canal extensions using the K file, ultrasonic file, lentulo spiral and EZ-Fill. II. Materials and Methods Forty resin blocks were attained from cutting Endo-training Bloc with diamond saw. In each parallelepiped block, the simulated root canal was made with ＃20, 08taper GT file. After each block was longitudinally split into two halves using mallet and chisel, a standardized groove of 4mm in length, located 2mmapart from the root apex, was prepared on one wall of two halves using the custom-made knife to simulate the canal extensions with various irregularities.(omitted)

• Bulletin of the Korean Mathematical Society
• /
• v.56 no.5
• /
• pp.1257-1272
• /
• 2019

This article concerns the structure of idempotents in reversible and pseudo-reversible rings in relation with various sorts of ring extensions. It is known that a ring R is reversible if and only if $ab{\in}I(R)$ for $a,b{\in}R$ implies ab = ba; and a ring R shall be said to be pseudoreversible if $0{\neq}ab{\in}I(R)$ for $a,b{\in}R$ implies ab = ba, where I(R) is the set of all idempotents in R. Pseudo-reversible is seated between reversible and quasi-reversible. It is proved that the reversibility, pseudoreversibility, and quasi-reversibility are equivalent in Dorroh extensions and direct products. Dorroh extensions are also used to construct several sorts of rings which are necessary in the process.