• Journal of the Korean housing association
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• v.8 no.3
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• pp.219-230
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• 1997

Lack of technical standards, specification and inadequate execution in masonry wall construction in Korea lead to produce serious flaw problems such as crack, efflorescene, and upset etc.. The purpose of this paper is to present the practical details for Masonry cavity wall construction to prevent rain penetration and to accommodate differential movement between the inner and outer wythes of cavity walls. Considering rain penetration and differential movement of both wythes of cavity walls, provision of an adequate air space, an airtight back-up wall, clean cavity with weepholes and vents, properly positioned flashing, tie and shelf angle etc. depend on the cavity wall types will help ensure good performance. The present details included noncorrosive hot dip galvanized steel or stainless steel for metal components, plastic and ultra violet resistant polypropylene Copolymer for other components was taken into account the construction method and several types of cavity walls in Korea

• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.710-717
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• 1998

The pH changes in 3 cavities prepared at the facial inner dentin and lingual outer dentin of the cervical portion and apical portion of roots filled with calcium hydroxide containing sealers were investigated. 50 extracted permanent teeth with single canal were instrumented with step-back method. An irrigant of 5% NaOCl was used between files. Then 3 small cavities were prepared. The cavity of apical portion and inner dentin cavity of coronal portion was cut a distance of about 1.0mm from the canal wall and outer dentin cavity of coronal portion was cut to a depth of about 0.5mm from root surface. 10 teeth of control group was not filled. 20 teeth were not flushed with 17% EDTA before using root canal sealers and then divided into 2 groups obturated with Sealapex and Apexit. The remaining 20 teeth were flushed with 17% EDTA and 5% NaOCl to remove smear layer and divided into 2 groups obturated with Sealapex and Apexit. The pH change of the dentin in each cavity was measured at 0, 1, 3, 5, 7, 15, 30 days with pH microelectrode(WPI Co., USA). The results were as follows: 1. The groups obturated with Sealapex and Apexit(calcium hydroxide based-sealers) have no increase in the pH level at root dentin. And there is no significant difference in pH level between groups obturated with Sealapex and Apexit(P>0.05). 2. Differences in pH levels between the treated and untreated groups with EDTA were not significant(P>0.05). 3. There is no significant difference in pH level between apical and cervical dentin, inner and outer dentin throughout the duration of the experiment(P>0.05).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.1
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• pp.21-28
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• 2017

Curtain-wall systems have been widely applied to buildings because of their lightweight and constructability characteristics. However, as curtain-wall systems include many building materials, vapor barriers can become damaged and condensation can occur. Due to the material properties of stone curtain-walls, the external appearance and structure of a building could be damaged and the insulating performance of the curtain-wall could be worse. Natural ventilation using an air cavity in a curtain-wall is expected to be effective for the prevention of condensation in inner walls and for the reduction of building cooling energy use in the summer. The purpose of this experimental study is to analyze the influence of a ventilated cavity on the insulating performance of a curtain-wall and the ventilated cavity depth and ratio of top opening needed to prevent condensation in a curtain-wall.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.164-167
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• 2003

In this study, we developed the mold for the plastic cavity filter which is a kind of a wireless communication device. Since the cavity filter is made of aluminium, the cost of fabrication is high and the production rate is low. But we can produce plastic cavity filter part by injection molding process with the mold which was designed by our team. The dimension and surface quality of plastic cavity filter was investigated by varying the molding method (conventional and MmSH process) and two different types of resin(PC/ABS and ABS). In case of ABS part, the shrinkage of the inner partition walls was decreased when we adopted MmSH method. The weight of both ABS and PC/ABS parts increased and the surface roughness decreased with MmSH process.

• Geomechanics and Engineering
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• v.20 no.5
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• pp.399-410
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• 2020

Cavities often develop behind the vault during the construction of double-arch tunnels, generally in the form of various defects. The study evaluates the impact of cavities behind the vault on the mechanical and failure behaviors of double-arch tunnels. Cavities of the same sizes are introduced at the vault and the shoulder close to the central wall of double-arch tunnels. Physical model tests are performed to investigate the liner stress variation, the earth pressure distribution and the process of progressive failure. Results reveal that the presence of cavities behind the liner causes the re-distribution of the earth pressure and induces stress concentration near the boundaries of cavities, which results in the bending moments in the liner inside the cavity to reverse sign from compression to tension. The liner near the invert becomes the weak region and stress concentration points are created in the outer fiber of the liner at the bottom of the sidewall and central wall. It is suggested that grouting into the foundation soils and backfilling injection should be carried out to ensure the tunnel safety. Changes in the location of cavities significantly impact the failure pattern of the liner close to the vault, e.g., cracks appear in the outer fiber of the liner inside the cavity when a cavity is located at the shoulder close to the central wall, which is different from the case that the cavity locates at the vault, whereas changes in the location of cavities have a little influence on the liner at the bottom of the double-arch tunnels.

• 한국전자현미경학회:학술대회논문집
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• 2007.05a
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• pp.75-78
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• 2007

The localization of cellulase were investigated in the capitate glandular trichomes of Pelargonium ${\times}$ fragransby a transmission electron microscopy. The secretory cells of capitate trichomes involved in biosynthesis and its secretion. Secretory material is transported to the space between the plasma membrane and cell wall, and subsequently accumulated in the secretory cavity. The splitting of secretory cell wall during the formation of secretory cavity is suggested that wall-forming enzymes, such as cellulase, may contribute to the wall separation process. Cellulase reaction product was localized in the secretory cell, the secretory cavity and in the subcuticular wall of glandular trichomes. Reaction products were present over fibrillar matrix in the secretory cavity associated with both the inner wall and the subcuticular wall.

• Structural Engineering and Mechanics
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• v.35 no.4
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• pp.409-430
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• 2010

The present paper will be concerned to the investigation of the stress-strain field around the cavity that is loaded or partially loaded at the inner surface by the rotationally symmetric loading. The cavity of the spherical, cylindrical or elliptical shape is situated in a stressed elastic continuum, subjected to the gravitation field. As the contribution to the similar investigations, the paper introduces the new function of loading in the form of the infinite sine series. Besides, in this paper the solution of stresses around an oblong ellipsoid cavity, has been obtained using appropriate curvilinear elliptical coordinates. This analytical approach avoids the solutions of the same problem that lead to expressions that contain rather complex integrations. Thus the presented solutions provide the applicable and explicit expressions for stresses and strains developed in infinite series with easily determinable coefficients by the use of contemporary mathematical packages. The numerical examples are also included to confirm the convergence of the obtained solutions.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.303-310
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• 2004

To establish a prediction table of parturition day real-time B-mode ultrasonographic examinations were performed in 12 pregnant Shih-tzu bitches. Measurement of inner chorionic cavity diameter and fetal head diameter was performed from 15 days of gestation to parturition. These were converted retrospectively based on the day of parturition (Day 0). The data of inner chorionic cavity diameter obtained from Day -44 to Day -25 and fetal head diameter obtained from Day -25 to Day -1 were used to compile a prediction table of parturition day. The 22 pregnant Shih-tzu with unknown mating time were examined to assess an accuracy of the table established in this study. And these results were applied to the prediction of parturition day and compared to actual parturition day. Parturition day prediction based on the inner chorionic cavity diameter and fetal head diameter was 100% accurate within ${\pm}2$ days. In addition, the accuracy for parturition day within 0, ${\pm}1$, and ${\pm}2$ days interval using the prediction table of parturition day were 68, 82, and 100%, respectively. Therefore, the prediction table of parturition day seems to be a useful tool for the prediction of parturition day in practice.

• 한국전산유체공학회:학술대회논문집
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• 2001.05a
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• pp.176-180
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• 2001

For windshield defrosting, flow analysis of inner room(vehicle) and heat conduction on the windshield surface are undertaken. Simulation for defrosting enthalpy method is usedand verification of heat and fluid flow analysis for room is done in cavity flow. The defrosting process is three dimensional phenomena and phase is changing. The result of defrosting analysis are well presenting the phase change and these results offer basic design data for defrosting phenomena.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.37-45
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• 2014

This paper is a study of the water sensor using a coaxial cavity resonator. This water sensor uses the resonant frequency variation of the coaxial cavity resonator when there is a water drop of the used coaxial cavity resonator. And we made resonant frequencies by controlling the input voltage of the oscillator which will be mainly resonated in the coaxial cavity resonator. First, we made the coaxial cavity resonator by simulating the resonator structure with the proposed size and we expect the resonant frequency from the simulation and then we decide the VCO from the result. Second, we made the water drop detecting sensor circuit and measured the water sensor. We decided the size of the resonator as inner conductor 5mm, outer conductor 14mm, the height of resonator 9.5mm, and the height of the glass 6mm from the simulated result. The simulated resonant frequencies are 3.09GHz and we made the VCO frequency ranges from 2.56GHz to 3.2GHz. The measured resonant frequency is 2.97GHz and the return loss is under -8. 4 dB at the center frequency. When the water is dropped on the glass of the resonator, the voltage has changed from 690mV to 145mV. It shows the proposed water sensor can detect the water by the resonant frequency variation of the resonator.