• 상하수도학회지
• /
• 제30권5호
• /
• pp.501-509
• /
• 2016

In this study, a flat-type photocatalytic reactor is applied under solar irradiation for simultaneous treatment of target pollutants: reduction of Cr(VI) to Cr(III) and oxidation of EDCs (BPA, EE2, E2). An immobilized type of photocatalyst was fabricated to have self-grown nanotubes on its surface in order to overcome limitations of powdery photocatalyst. Moreover, Ti mesh form was chosen as substrate and modified to have both larger surface area and photocatalyst content. Ti mesh was anodized at 50V and $25^{\circ}C$ for 30min in the mixed electrolytes ($NH_4F-H_2O-C_2H_6O_2$) and annealed at $450^{\circ}C$ for 2 hours in ambient oxygen to have anatase structure. Surface characterization was done with SEM and XRD methodologies. Fabricated NTT was applied to water treatment, and coexisting Cr(VI) and organics (EDCs) enhanced each other's reactions by scavenging holes and electrons and thus impeding recombination. Also, several experiments were conducted outdoor under direct sunlight and it was observed that both solar-tracking and applying modified photocatalyst were proven to enhance reaction efficiency.

• 한국의류산업학회지
• /
• 제13권3호
• /
• pp.418-424
• /
• 2011

The purpose of this study was to reveal the effects of the seam type on the fabric drape to provide the basic knowledge for proper seam type according to the design of sewing products. Seven kinds of specimens were constructed with seam (no seam, welt seam with over-edged finish, welt seam with bias bound finish, plain seam with over-edged finish, plain seam with bias bound finish, french seam, and flat fell seam) in wrap direction of the fabric. Using a drape measurement system involving two 18 cm diameter supporting disks, and a digital camera, the images of draped specimens were captured and processed. Drape behavior was evaluated in terms of drape coefficient, node number, and drape profile. Significant differences were found in drape coefficient by the seam types. The specimens with french seam and flat fell seam showed higher drape coefficients compared to those with welt seam and plain seam. Node numbers in the drape profiles showed positive correlation with the weight of the specimens, however, no significant differences were observed in node numbers by the seam types. Significant differences were found in the length of the seamed part by the seam types. The specimens with french seam and flat fell seam showed longer length of the seamed part compared to those with welt seam and plain seam. The ratio of the maximum length in the seam direction to the maximum length perpendicular to the seam direction showed significant differences by the seam types.

• 건축역사연구
• /
• 제33권2호
• /
• pp.7-15
• /
• 2024

The composition of the upper structure, which can be found in the 3-Dori type buildings in Yang-dong Village, varies significantly from time to time. The upper structure of the Gwan-ga-jeong, known as a house in the mid-Joseon Dynasty, consists of a basic 3-Dori type structure in which a beam is placed under 3-Dori and supported with two flat columns. On the other hand, the upper structure of I-hyang-jeong historic house, built in the 17th century, is different in that it has a stud between the two flat columns. The upper structure of Sa-ho-dang historic house, a 19th-century building is different from the upper structure of the buildings of the previous period in that three flat columns were used. As such, the difference in the composition method of the upper structure according to the construction period is closely related to the introduction of the Toi-maru, which is mainly explained by the boundary space. In addition, it can be expected that the introduction of the Toi-maru originated from the influence of the change in the plan. This study was conducted to examine the correlation between the plan and the composition of the boundary space through various typology of the 3-Dori upper structure distributed intensively in Yang-dong Village.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2004년도 학술대회지
• /
• pp.880-882
• /
• 2004

This paper presents the design and simulation results of 7 waveguide dielectric rod array antennas for 7 channel DBF(Digital beamformer) receivers for stratospheric system. A waveguide. dielectric antenna type, which has FTEP(Flat-toped element pattern) to manufacture easily. Also, the calculated element patterns according to the permittivity are compared. The designed antenna will be used for generating multibeam radiation pattern by means DBF.

• 대한수학회지
• /
• 제53권3호
• /
• pp.623-643
• /
• 2016

In this paper, we study piecewise Noetherian (resp., piecewise w-Noetherian) properties in several settings including flat (resp., t-flat) overrings, Nagata rings, integral domains of finite character (resp., w-finite character), pullbacks of a certain type, polynomial rings, and D + XK[X] constructions.

• Journal of the Optical Society of Korea
• /
• 제11권3호
• /
• pp.118-123
• /
• 2007

The emitting structure of multi-channel-type flat fluorescent lamps (FFLs) combined by a lenticular-lens-patterned diffuser plate was optimized by the ray tracing technique. The optimal parameters such as the distance between the channels of the FFL and the distance between the FFL and the diffuser plate were suggested from the viewpoint of the luminance uniformity. The best luminance uniformity, which was higher than 90%, was obtained at the channel distance of 4 mm and the distance of 12.5 mm between the FFL and the patterned diffuser plate.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.316-318
• /
• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generated from gas discharge and powder type electrolyminescent display(P-ELD) using a phenomenon of the light emission eaused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.305-307
• /
• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generated from gas discharge and powder type electro luminescent display using a phenomenon of the light emission caused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.

• 대한수학회논문집
• /
• 제34권3호
• /
• pp.911-920
• /
• 2019

In this paper we characterize semiconformally flat spacetimes and a spacetime with harmonic semiconformal curvature tensor. At first in a semiconformally flat perfect fluid spacetime we obtain a state equation and prove that in particular for dimension n = 4, the spacetime represents a model for incoherent radiation. Next we prove that perfect fluid spacetime with harmonic semiconformal curvature tensor is of Petrov type I, D or O and the spacetime is a GRW spacetime. As a consequence we obtain several corollaries.

• 한국진공학회지
• /
• 제15권3호
• /
• pp.241-245
• /
• 2006

본 연구에서는 대면적 플라즈마 공정에 적용 가능한 고밀도 플라즈마를 발생시키기 위하여 기존의 내장형 serpentine-type 안테나와 새롭게 고안된 내장형 유도결합형 multiple U-Type 안테나를 1020mm X 920mm(기판 880 X 660mm)의 챔버에서 연구하였다. 내장형 유도결합형 multiple U-type을 적용한 플라즈마는 serpentine-type과 비교하여 더 높은 플라즈마 밀도, 높은 radical 밀도, 좋은 균일도를 관찰할 수 있었다. 이는 serpentine-type의 경우와 비교하여 보다 적은 정상파 효과와 높은 유도결합에 기인한다. 내장형 유도결합형 multiple U-type 안테나의 적용으로 $2\times10^{11}/cm^3$의 높은 플라즈마 밀도를 얻을 수 있었고 5000W의 입력전압과 Ar 가스 15mTorr 공정압력조건에서 4%의 균일도를 관찰할 수 있었다.