• Steel and Composite Structures
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• v.11 no.4
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• pp.291-305
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• 2011

The new structure consisting of continuous compound spiral hoop reinforced concrete (CCSHRC)column and steel concrete composite (SCC) beam has both the advantages of steel structures and concrete structures. Two types of beam-to-column connections applied in this structural system are presented in this paper. The connection details are as follows: the main bars in beam concrete pass through the core zone for both types of connections. For connecting bar connection, the steel I-beam webs are connected by bolts to a steel plate passing through the joint while the top and bottom flanges of the beams are connected by four straight and two X-shaped bars. For bolted end-plate connection, the steel I-beam webs are connected by stiffened extended end-plates and eight long shank bolts passing through the core zone. In order to study the seismic behaviour and failure mechanisms of the connections, quasi-static tests were conducted on both types of full-scale connection subassemblies and core zone specimens. The load-drift hysteresis loops show a plateau for the connecting bar connection while they are excellent plump for bolted end-plate connection. The shear capacity formulas of both types of connections are presented and the values calculated by the formula agree well with the test results.

• Journal of ILASS-Korea
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• v.23 no.1
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• pp.9-15
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• 2018

Breakup lengths of circular and elliptical liquid jets in a subsonic crossflow were experimentally studied. Two circular-shaped and four elliptical-shaped plain-orifice injectors, which had different aspect ratios and orifice length to diameter ratios, were used to provide various liquid jet conditions such as steady, cavitation, and hydraulic flip. By varying the injection pressure drop from 1 bar to 6 bar, spray images were taken using a shadowgraph technique. Breakup lengths were measured and analyzed. As the aspect ratio in orifices increased, liquid column breakup lengths normalized by the equivalent diameter were reduced irrespectively of the switching of the major or minor axis to the crossflow. It was also found that when hydraulic flip developed inside the orifice, x-directional breakup lengths more decreased for both circular and elliptical liquid jets.

• Korean Journal of Heritage: History & Science
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• v.45 no.3
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• pp.4-27
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• 2012

The five capital(五京) was installed in the $Li{\acute{a}}o$(遼) Dynasty. $Sh{\acute{a}}ngj{\bar{i}}ng$(上京) was the main capital city of the $Li{\acute{a}}o$(遼) Dynasty. $Zh{\bar{o}}ngj{\bar{i}}ng$(中京) was the second capital(陪都); and the other three was the capital city with symbolic meaning. The layout of $Sh{\grave{a}}ngj{\bar{i}}ng$ was the '日-shaped plan; this was newly advent structure of ancient Chinese capital city system. $Zh{\bar{o}}ngj{\bar{i}}ng$(中京) was surrounded by multiple ramparts influenced by the $Bi{\grave{a}}nli{\acute{a}}ng$ Fortress (?梁城). Three capitals, Nanjing(南京), $X{\bar{i}}j{\bar{i}}ng$(西京) and $D{\bar{o}}ngj{\bar{i}}ng$(東京), were reconstructed on the foundation of the previously constructed town in $T{\acute{a}}ng$(唐) or Bohai(渤海) Fortress (舊城). The structure and Planning of $Sh{\grave{a}}ngj{\bar{i}}ng$(上京) in the $Li{\acute{a}}o$(遼) Dynasty, had significantly influenced in the capital city planning of the $J\bar{i}n$(金), $Yu{\acute{a}}n$(元) and Qing(淸) Dynasties of China

• The Journal of Korean Academy of Prosthodontics
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• v.19 no.1
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• pp.7-16
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• 1981

The technology of precision attachments has developed at such a pace that from a very few T-shaped attachments and bar attachments from the years 1915 to 1935 since removable bridge utilizing a T-shaped intracoronal attachment was constructed by Dr. Herman E.S. Chayes in 1906. There are now more than 120 models of the most diversified designs, ready made or laboratory fashioned. In 1971, 126 attachments were listed and classified by Mensor in his E M Attachment Selector. This selector consists of five charts giving specifications as to type, vertical dimensions, application, type of resilience, size of movement, type of retention and type of material and alloy. Thus the E M Attachment Selector is a useful guide for dentists to choose the attachment for his patients. But dentists should apply the attachment in each patient's case according to an accurate diagnosis and treatment plan. This paper is a case report of removable partial dentures utilizing CSP, PD and Bar attachment on a patient who needed full mouth reconstruction. Patient has right first, second molar and left first molar on the upper arch and also left first molar, first premolar and right canine on the lower arch. (Fig. 5)All remaining teeth are relatively healthy in their supporting tissues. On upper arch, ring shape CSP attachment was designed on left first molar and modified ring shape CSP attachment was designed on right first and second molar as the direct retainer of the removable partial denture. Full palatal coverage was used as the major connector in this case. (Fig. 23) On lower arch, author first splinted with a fixed bridge between left first molar and second premolar and a splint bar between left second premolar and right canine. (Fig. 11) A lower removable partial denture in which was designed with an Aker clasp on the left first molar and a PD attachment on .the right canine was constructed. (Fig. 17) This denture could get additional support from anterior splint bar. After both removable partial dentures were delivered to the patient (Fig. 26), author evaluated function of the dentures and supporting structures of the abutment teeth by means of clinical and X-ray examinations for eighteen months. According to the examination data author came to the conclusion that the prognosis of this case was excellent.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.77.4-78
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• 2017

The presence of double red clump (RC; metal-rich counterpart of horizontal-branch) in high latitude field of the Milky Way (MW) bulge is widely interpreted as evidence for an X-shaped structure originated from the bar instability. However, Lee et al. (2015) recently suggested an alternative model, according to which the double RC is metal-rich manifestation of multiple stellar population phenomenon observed in globular clusters (GCs). Here we show that stars in bright RC are enhanced in CN compared to those in faint RC from our low-resolution spectroscopy. CN traces N, and N-rich stars are also enhanced in Na and He in GCs. Since GCs are the only environment that produce second generation stars with enhanced N, Na, & He, this is a direct evidence that stars in the classical bulge component of the MW were mostly provided by proto-GCs.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.39.3-40
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• 2018

The presence of double red clump (RC) in the Milky Way bulge is widely accepted as evidence for a giant X-shaped structure originated from the bar instability. We suggested, however, a drastically different interpretation based on the multiple stellar populations phenomenon as is observed in globular clusters. Our discovery of a significant difference in CN-band between two RCs strengthens our scenario. On the other hand, recent Gaia survey provides trigonometric parallax distances for more than one billion stars in our Galaxy. These distance measurements would provide the important test as to the origin of the double RC in the Milky Way bulge. In this talk, we will present our preliminary results from Gaia DR2.

• Restorative Dentistry and Endodontics
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• v.47 no.3
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• pp.32.1-32.11
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• 2022

Objectives: This study aimed to evaluate the influence of inorganic composition and filler particle morphology on the mechanical properties of different self-adhesive resin cements (SARCs). Materials and Methods: Three SARCs including RelyX Unicem-2 (RUN), Maxcem Elite (MAX), and Calibra Universal (CAL) were tested. Rectangular bar-shaped specimens were prepared for flexural strength (FS) and flexural modulus (FM) and determined by a 3-point bending test. The Knoop microhardness (KHN) and top/bottom microhardness ratio (%KHN) were conducted on the top and bottom faces of disc-shaped samples. Sorption (Wsp) and solubility (Wsl) were evaluated after 24 hours of water immersion. Filler morphology was analyzed by scanning electron microscopy and X-ray energy dispersive spectroscopy (EDS). FS, FM, %KHN, Wsp, Wsl, and EDS results were submitted to 1-way analysis of variance and Tukey's post-hoc test, and KHN also to paired t-test (α = 0.05). Results: SARC-CAL presented the highest FS value, and SARC-RUN presented the highest FM. SARC-MAX and RUN showed the lowest Wsp and Wsl values. KHN values decreased from top to bottom and the SARCs did not differ statistically. Also, all resin cements presented carbon, aluminum, and silica in their composition. SARC-MAX and RUN showed irregular and splintered particles while CAL presented small and regular size particles. Conclusions: A higher mechanical strength can be achieved by a reduced spread in grit size and the filler morphology can influence the KHN, as well as photoinitiators in the composition. Wsp and Wsl can be correlated with ions diffusion of inorganic particles.

• The Journal of Advanced Prosthodontics
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• v.13 no.4
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• pp.258-267
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• 2021

PURPOSE. The purpose of this study was to compare the surface roughness, phase transformation, and surface topography of dental zirconia with three different yttrium oxide compositions under same grinding and polishing conditions. MATERIALS AND METHODS. Three zirconia disks (IPS e.max ZirCAD LT, MT, MT multi, Ivoclar Vivadent AG, Schaan, Liechtenstein) were selected for experimental materials. Sixty-nine bar-shaped specimens were fabricated as 12.0 × 6.0 × 4.0 mm using a milling machine and glazing was conducted on 12.0 × 6.0 mm surface by same operator. With a custom polishing device, 12.0 × 6.0 mm surfaces were polished under same condition. Surface roughness (Ra[㎛]) was measured before grinding (C), after grinding (G), and at every 3 steps of polishing (P1, P2, P3). X-ray diffraction and FE-SEM observation was conducted before grinding, after grinding, and after fine polishing (P3). Statistical analysis of surface roughness was performed using Kruskal-Wallis test and Mann-Whitney-U test was used as a post hoc test (α = .05). RESULTS. There were no significant differences of surface roughness between LT, MT, and MM groups. In LT, MT, and MM groups, P3 groups showed significantly lower surface roughness than C groups. X-ray diffraction showed grinding and polishing didn't lead to phase transformation on zirconia surface. In FE-SEM images, growths in grain size of zirconia were observed as yttrium oxide composition increases. CONCLUSION. Polished zirconia surface showed clinically acceptable surface roughness, but difference in yttrium oxide composition had no significant influence on the surface roughness. Therefore, in clinical situation, zirconia polishing burs could be used regardless of yttrium oxide composition.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.21-35
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• 2006

This paper examines critical successful elements related to the management of new product development process. For this, we have selected a VK-X100, slim bar type cellular phone, produced by VK mobile co., which was thought as a successful product development case and then analysed the case from a concept driven strategic product development's point of view. We have performed in-depth interviews with project managers, engineers and designers to get information on the product development process and analysed huge amount of data obtained from web-sites, global market indicators, and related firms' materials to find a changing trend of market conditions. The findings suggest that the successful new Product development and management is shaped by a number of different factors, such as the business environments, firm's technological level, firm's deep market insight capabilities, nature of the product development activities, and so on. Finally, we suggested the limitation of our research and further research subjects that would be required to support our findings.

• Journal of applied mathematics & informatics
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• v.39 no.5_6
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• pp.785-804
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• 2021

The proposal of new families has been worked out by many authors over recent years. Many ways to generate new families have been developed as the methods of addition, linear combination, composition and, one of the newer, the T-X family of distributions. Using this latter method, Korkmaz et al. (2018) proposed a new class called Weibull Marshall-Olkin-G (WMO-G) family. In the present work, we propose a new distribution, based on the WMO-G family, using the Lomax distribution as baseline, called Weibull Marshall-Olkin Lomax (WMOL) distribution. The hazard rate function of this distribution can be increasing, decreasing, bathtub-shaped, decreasing-increasing-decreasing and unimodal. Some properties of the proposed model are developed. Besides that, we consider method of maximum likelihood for estimating the unknown parameters of the WMOL distribution. We provide a simulation study in order to verify the asymptotic properties of the maximum likelihood estimates. The applicability of the new distribution to modeling real life data is proved by two real data sets.