• Journal of Welding and Joining
• /
• v.29 no.3
• /
• pp.51-57
• /
• 2011

Bead shape control with gas force process has been developed to overcome the concave back bead in pipe orbital welding. However, It is impossible to make a convex back bead using the existing gas nozzle, because it has high gas-consuming and low gas force. The purpose of this paper, to develop optimum shape of nozzle which to reduce the consumption of gas, maximizing the shield gas force with low cost and high productivity coincide the Green welding. In this paper venturi-type nozzle was designed by using the Venturi meter and compared velocity, pressure, arc shape in the flat position with existing CP-nozzle. As a result, Venturi-type nozzle's maximum velocity and pressure was improved at the same flow rate. Also heat input was increased by the arc contraction in the flat position.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.1
• /
• pp.16-23
• /
• 2015

In this paper, a bent microstrip patch antenna, which is suitable for band-type wearable devices and RF configuration, to be used in the WCDMA2100 mobile network is proposed. The proposed antenna using RF configuration which is consisted of separated Tx and Rx frequency band is designed to operate or function in WCDMA2100 Tx frequency band only and it is not strongly affected by the human body because of the conductor at the bottom side. At both flat case and bent case, the proposed antenna's maximum gain satisfies at least 5.3 dBi, and its -6 dB return loss bandwidth is wider than 20 MHz. The simulated surface absorption rate($SAR_{1g}$) result is under 0.7 [W/kg]. The proposed antenna suits in band-type wearable devices which is worn on wrists or arms.

• Particle and aerosol research
• /
• v.14 no.4
• /
• pp.121-133
• /
• 2018

In this study, we developed a flat-plate type wet electrostatic precipitator that generates stable corona discharge compared to wire type discharge electrode. In order to compare the particle removal efficiency according to the shape of the discharge electrode such as the variation of the horizontal and vertical distance between spiked edges, and the variation of the height of discharge pin support were tested. As a result, when the horizontal distance between spiked edges was increased up to 36 mm, the vertical distance between spiked edges was increased up to 54 mm, and the height of the discharge pin support was increased up to 76 mm, the removal efficiency of PM10 was maintained at approximate 60.0%. Furthermore, the removal efficiency of particles over $5{\mu}m$ was about 80% or more. When the flow rate was 4 m/s, the gap between collection plates was 60 mm, and -14 kV was applied to the discharge electrode. The particle removal efficiency of the flat-plate type electrostatic precipitator was maintained when the horizontal and vertical distance between spiked edges, and the height of the discharge pin support was below a certain level. Those variables may be the important design factors for the shape of the discharge electrode. Therefore, when designing the electrostatic precipitator with multiple channels, the horizontal and vertical distance between spiked edges, and the height of discharge pin support must be selected in consideration of the weight of the discharge electrode and the processing cost.

• Journal of the Society of Naval Architects of Korea
• /
• v.60 no.1
• /
• pp.31-37
• /
• 2023

In the present study, a method of performing cavitation erosion test directly on the anodized surface of the rudder model is proposed, not applying ink or paint on its surface. An image processing technique is newly developed to quantitatively evaluate the erosion damages on the rudder model surface after erosion test. The preprocessing saturation image, image smoothing, adaptive hysteresis thresholding and eroded area detection algorithms are in the image processing program. The rudder cavitation erosion tests are conducted in the rudder deflection angle range of 0° to -4°, which is used to maintain a straight course at the highest speed of the targeted navy ship. In the case of the conventional flat-type full-spade rudder currently being used in the target ship, surface erosion can occur on the model rudder surface in the above rudder deflection angle range. The bubble type of cavitation occurs on rudder surface, which is estimated to be the main reason of erosion damage on the rudder surface.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.1
• /
• pp.61-69
• /
• 2012

Recently, tower type apartment has been a main stream at the apartment market, in Korea. Tower type apartment has features that is easy to maintain a proper distance between apartment buildings, and to keep a prospect comparing to flat type apartment However, there is usually a inner curved area at tower type apartment, and it is able to make an unhealthy environment because of shaded area through a day and a bad air flow. In this study, the duration of sunshine and the exterior air flow environments are examined. As results, the duration of sunshine at the inner curved area of tower type apartment was extremely short, and the exterior air flow environment was very bad for the low air velocity of about 0.08m/s. Installing pilotis in the 1st floor which faces to the inner curved area makes the good improvement of exterior air flow environment.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• pp.181-182
• /
• 2015

The production technologies of free-form concrete panels are emerging to satisfy the need of modern complex shaped in architectural design. This study aims for introducing and improvising the innovative technique called Rod type mold that overcomes the difficulties in some extent by enabling the mold to be used many times, making the shape of the mold adjustable in a flexible way and describing its production process to provide the alternative solution for the construction of free-form mold with considering the features including reusability and optimization cost across its production process. In this study, the freeform concrete panel shape was designed and experiment was done using computerized numeric control machine and rod type mold. The problems appeared on achieving desired shape while operating on rod type mold. The process of identifying all the root causes and contributing causes that may have generated an undesirable condition were done. Consequently, the conical or semicircular shaped was proposed for the end of Numerical control rod and replaced it with the existing flat shaped end to avoid the detachable problem and to improve rod type mold performance.

• Fashion & Textile Research Journal
• /
• v.20 no.5
• /
• pp.548-555
• /
• 2018

The purpose of this study is to analyze the patterns of commercial Cheollik dresses by size analysis and wearing evaluation. Six kinds of commercial Cheollik dress patterns distributed on the market were selected and classified into two types group, A type group(A-1, A-2, A-3) consisting of flat type sleeve pattern and B type group(B-1, B-2, B-3) consisting of three-dimensional type sleeve pattern depending on the sleeve type. The size of the Cheollik dress pattern was analyzed, and wearing evaluations of the appearance, movability were carried out. Cheollik dress pattern was made in various size and many patterns were produced in the form of omission of components such as seop. It should be based on the understanding of the form and composition of the traditional Cheollik for pattern development. As a result of the wearing evaluation, A-2 showed the highest evaluation in the appearance and movability evaluations in type A. B-2 was the highest evaluation in appearance evaluation in type B. But in the evaluation of the movability, B-2 received the lowest evaluation because of little allowance. Therefore, the allowance in clothes should be considered enough for the movability. The result of this study can be provided as a basic data for the development of Cheollik dress pattern reflecting modern trend and the traditional beauty.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.19 no.6
• /
• pp.1027-1039
• /
• 1995

Clothing fitness is strongly required in the apparel industry, and draping is an effective tool to increase fitness to the wearers. A more sophisticated and systematic information of the somatotype, accordingly, is necessary for better cress form design. This study was performed to provide fundamental data on middle aged women's upper torso for dress form designers and pattern makers by classifying the somatotype based on each individual's lateral view, and analyzing the characteristics of their somatotype. Data were analyzed by factor analysis, cluster analysis, analysis of variance. Factor analysis was used to 23 items from photometric measurment and cluster analysis was applied for classification of upper torso forms. Through cluster analysis using 5 factor scores, 3 somatotypes were categorized from th lateral view 1) Type I was straight somatotype in which the plumb line passes throught the lobe of the ear, the shoulder joing and the mid abdominal region laterally. This type of woman was slender and shorter than average. 2) Type II was bending somatotype in which the upper portion of upper torso is bent forward. This type of woman was taller and fatter than average. 3) Type III was swayback somatotype in which the upper portion of protruding point on the back is bent forward but the lower portion of protruding point had characteristic of turning over somatotype. This type of woman had storter length on the front and longer lenght on the back, slender type and flat chest.

• Journal of Biosystems Engineering
• /
• v.42 no.1
• /
• pp.12-22
• /
• 2017

Purpose: This aim of this study was to develop a pick-up type pulse crop harvester for harvesting cut and dried pulse crop. Methods: The pick-up type pulse crop harvester was designed and constructed. Its specifications and operating performance were investigated. Results: Compared with conventional bean harvesters, the pick-up type pulse crop harvester adopted seven rows of chains with tines to pick-up the cut and dried pulse crop on a flat or ridged field, two transverse threshing drums with steel wire teeth to reduce the threshing speed, and a tilt plate and plastic bucket elevator for conveying clean grain to reduce damage. The threshing speed and the oscillating frequency of the separating and cleaning parts according to crop type and condition could be varied easily to efficiently use engine power and to improve harvesting performance. The harvester showed forward speed ranges of 0 ~ 1.5 m/s during harvesting operation, and 0 ~ 2.5 m/s during road travelling. The pick-up width of the harvester was about 1 m. Conclusions: The pick-up type self-propelled 51.5 kW harvester was designed and constructed to harvest cut and dried pulse crop. The effective field capacity of the harvester was predicted as above 40 a/h.

• Journal of architectural history
• /
• v.31 no.1
• /
• pp.29-39
• /
• 2022

The remaining Joongjaesil(中齋室)-type pavilions in the eastern part of the Jirisan Mountain area showed more complex characteristics than those in the western part. The front number of kan(間) had two, three, and four kan (間) types, but the number of kan on the side was consistent with two regardless of the number of kan on the front. The pavillion is classified into 'central type', 'towards the backward type', and 'expanded by backwards type' according to the location of Joongjaesil. Joongjaesil's size, which characterizes the characteristics of Joongjaesil-type Pavilion, is related to the building's front number of kan. Front number of kan. When this space was increased by one space to four spaces, Joongjaesil must have two spaces. The pavilion with four bays in front showed the characteristics of being concentrated in Sancheong and Jinju, the eastern part of the Jirisan Mountain area. In the eastern region, many high pavilions remain, and the upper structure of the pavilion was insignificant, but the flat shape and public construction showed strong locality.