• 한국정밀공학회지
• /
• 제17권4호
• /
• pp.97-105
• /
• 2000

One of the most important steps to determine the blank shape and dimensions in deep drawing process is to calculate the surface area of the product. In general, the surface area of axisymmetric products is calculated by mathematical or graphical methods. However, in the case of non-axisymmetric products, it is difficult to calculate the exact surface area due to errors as separated components. Fortunately, it is possible for elliptical products to recognize the geometry of the product in the long side and short side by drafting in another two layers on AutoCAD software. So, in this study, a surface area calculating system is constructed for a design of blank shape of deep drawing products. This system consists of input geometry recognition module and three dimensional modeling module, respectively. The suitability of this system is verified by applying to a real deep drawing product. The system constructed in this study would be very useful to reduce lead time and cost for determining the blank shape and dimensions.

• 한국군사과학기술학회지
• /
• 제7권4호
• /
• pp.138-145
• /
• 2004

Experimental study was conducted on cylindrical supersonic diffuser in order to investigate the effects of the ratios of diffuser area to nozzle throat area (Ad/At), diffuser area to nozzle exit area (Ad/Ae), nozzle exit area to its throat area (Ae/At), and diffuser length to its diameter (L/D), the free volume of vacuum chamber, and the relative distance between nozzle exit and diffuser inlet on the diffuser performance. The study showed that the minimum diffuser starting pressure (Po/Pa)st increased monotonically with increase in (Ad/At) as predicted by the normal shock and momentum theory models and the volume of vacuum chamber affected vacuum pressure level during diffuser operation at lower value of (Ad/Ae). The results of this investigation will be utilized in the design of real-scale high-altitude simulation test facility.

• 한국환경보건학회지
• /
• 제27권3호
• /
• pp.57-62
• /
• 2001

The study was conducted to measure the heavy metal pollution of soils at the playground for children and to investigate the characteristics of heavy metals distribution I city. The studied area was divided into two: the residential area and the industrial area. The samples of the sands and soils were collected from both areas. The results were obtained as follows. All average concentration of 6 different heavy metals was found to be lower than the standard of soil pollution. Zn, Pb and cu concentrations were higher than other species of heavy metals. The contents of heavy metals in the soil were higher than the sands. The average contents of Zn, Pb, Cu, As, Hg and Cd in soil were 38.36, 9.53, 7.31, 0.03, 0.18 and 0.09 mg/kg respectively. Comparing with the residential area, heavy metal concentrations of the industrial area were 4.60, 1.49, 2.60 and 4.29 times for Zn, Pb, Hg and Cd in soils, respectively.

• 한국멀티미디어학회논문지
• /
• 제20권3호
• /
• pp.456-464
• /
• 2017

The epigraphy is a text on metal or a text on stone. The value of epigraphy can be used to identify historical facts of the past. It is a good record to understand the past life and culture. But it is difficult to decode the character of the epigraphy which has been exposed to the outdoor for a long time. In this study, the proposed techniques are consisted of 3 parts: (1)The surface division into information area, non- information area, and undifferentiated area. And then, (2) The selection of points in the non-information area and finding a reference plane with the minimum error. (3) Flattening the points perpendicular to the reference plane and decoding characters on information area. This research contributes to narrow the scope of a particular letter and to read the controversial letters on the Pohang Jungsoengri Silla Stone Monument(Korea's national treasure number 318).

• 한국주거학회논문집
• /
• 제13권3호
• /
• pp.33-43
• /
• 2002

The purpose of this paper is to develop a space program of the new community center in multi-family housing. The community center defined in this study is a communal facility which integrate cultural and welfare facilities and activity programs into a complex. Through the analysis of the community programs and spaces for multi-family housing community, a new community center program is proposed. And basic area guidelines are proposed through the making of the space modelling of the important area of the center. According to the guidelines, more spaces compared to the present standards and conditions are needed for a new community center. However, the adjustment of area regulation is essential, considering the fast changing trend of resident's social needs. A new regulation system that controls the total area of function spaces of a community center, rather than controlling each function and area, is required. This kind of system makes it possible to decide programs freely within the limit of total floor area regulation by neighborhood's characteristics and residents'preference.

• 농촌계획
• /
• 제11권4호
• /
• pp.25-31
• /
• 2005

The present study was carried out to investigate the P fractions of surfical sediment of Dongjin sea area. Furthermore, potential released loading of adsorbed and non-apatite inorganic phosphorus were investigated in the sediment of Dongjin sea area. The contents of phosphorus fractions of the surficial sediment in Dongjin sea area were adsorbed-P 0.06%, nonapatite inorganic-P 13.02%, apatite-P 60.22%, and residual-P 26.70%. The most abundant fraction was apatite-P, residual-P, nonapatite inorganic-P, and adsorbed-P followed it. Potential released loading of adsorbed and non-apatite inorganic phosphorus surveyed 2.6 and 597ton respectively. These results show that sediment-managing and interception from external pollution are needed for water environmental maintenance of Dongjin sea area.

• 한국기계가공학회지
• /
• 제2권1호
• /
• pp.45-50
• /
• 2003

In any rapid prototyping process, the layer by layer building process introduces an area error between the staircase and the surface line specified by the computer-aided design model. This affects the dimensional accuracy as well as the surface finish for different Road Widths. This paper describes a methodology for computing the area error for any Road Width by the fused deposition modelling system. This technique can be applied to determine the best Road Width of the part, based on the minimum area error. This technique is verified by comparing the results with the experimental measurements of the area error with Road Widths.

• Journal of Preventive Medicine and Public Health
• /
• 제12권1호
• /
• pp.79-87
• /
• 1979

Analyses for 6 metals (Cd, Zn, Cu, Ni, Pb, Mn) by Atomic absorption spectrophotometer were made on hair samples of healthy 135 in urban area and 130 in rural area who have not dealt with the above metals in their daily working life. Marksd variations were found. Samples of urban area contained more cadmium, copper, lead and manganese than those of rural area. No sexual difference in mean value could be observed and the amount of metals in hair did not increase with age. And no age dependency was found. There was a statistically significant correlation between the concentrations of cadmium and lead in both urban and rural people; Pb = 1.50 Cd + 6.69 (r = 0.213, p<0.05) in urban area Pb = 1.44 Cd + 3.67 (r = 0.327, p<0.001) in rural area

• 로봇학회논문지
• /
• 제5권1호
• /
• pp.55-63
• /
• 2010

This paper describes performance improvement of GPS/DR Integration system using area decision algorithm and vehicle movement information. In GPS signal blockage area, i.e., tunnel and underground parking area, DR sensor errors are accumulated and navigation solution is gradually diverged. We use the car movement information according to moving area to correct the DR sensor error. Also, vehicle movement is decided as stop, straight line, turn and movement changing region through DR sensor data analysis. The car experiment is performed to verify the supposed method. The results show that supposed method provides small position and heading error than previous method.

• International Journal of Aeronautical and Space Sciences
• /
• 제11권2호
• /
• pp.118-125
• /
• 2010

This paper describes a mid-course guidance strategy based on the earliest intercept geometry (EIG) guidance. An analytical solution and performance validation will be addressed for generalized mid-course guidance problems in area air-defence in order to improve reachability and performance. The EIG is generated for a wide range of possible manoeuvres of the challenging missile based on the guidance algorithm using differential geometry concepts. The main idea is that a mid-course guidance law can defend the area as long as it assures that the depending area and objects are always within the defended area defined by EIG. The velocity of Intercept Point in EIG is analytically derived to control the Intercept Geometry and the defended area. The proposed method can be applied in deciding a missile launch window and launch point for the launch phase.