• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.604-610
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• 2008

A 2.4 GHz CMOS RF front-end using for ZigBee application is described The front-end consists of a low noise amplifier and a down-mixer and uses a 2 MHz IF frequency. A common source with resistive feedback and an inductive degeneration are adopted for a low noise amplifier, and a 20 dB gain control step is digitally controlled. A passive mixer for low current consumption is employed. The RF front-end is implemented in 0.18 ${\mu}m$IP6M CMOS process. The measured performance is 4.44 dB NF and -6.5 dBm IIP3 while consuming 3.28 mA current from a 1.8 V supply.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.153-160
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• 2016

Purpose: This study was conducted to experimentally investigate the structural safety of and identify critical locations in a front-end loader under impact loads. Methods: Impact and static tests were conducted on a commonly used front-end loader mounted on a tractor. In the impact test, the bucket of the front-end loader with maximum live load was raised to its maximum lift height and was allowed to free fall to a height of 500 mm above the ground where it was stopped abruptly. For the static test, the bucket with maximum live load was raised and held at the maximum lift height, median height, and a height of 500 mm from the ground. Strain gages were attached at twenty-three main locations on the front-end loader, and the maximum stresses and strains were measured during respective impact and static tests. Results: Stresses and strains at the same location on the loader were higher in the impact test than in the static test, for most of measurement locations. This indicated that the front-end loader was put under a severe environment during impact loading. The safety factors for stresses were higher than 1.0 at all locations during impact and static tests. Conclusions: Since the lowest safety factor was higher than 1.0, the front-end loader was considered as structurally safe under impact loads. However, caution must be exercised at the locations having relatively low safety factors because failure may occur at these locations under high impact loads. These important design locations were identified to be the bucket link elements and the connection elements between the tractor frame and front-end loader. A robust design is required for these elements because of their high failure probability caused by excessive impact stress.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.1
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• pp.171-187
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• 2016

The study performed a comparison analysis of market brand patterns for slim-fit dress shirts and analyzed the body surface development figure of men in their 40s using 3D body scan data and developed slim-fit dress shirt patterns suitable for middle-aged men. The sizes of slim-fit dress shirt patterns showed a slight difference depending on brand. The overlap map of slim-fit dress shirt patterns for brands demonstrates how difference of one-dimensional sizes reflect on two-dimensional patterns. This map provides useful information for pattern design and allows and easy recognition of pattern size differences. A try-on system evaluation through 3D-Simulation allows a grasp of the fitness of neckline and size tolerance of under the arms in front, the silhouette of side lines, and overall fitness in front that also allows analysis of the front/back balance of a shirt in side, the size tolerance proportion in front/back, and the fitness of the arm-hole line. Thus, we obtained try-on results that were equivalent to wearing actual clothing. According to the drafting size suggested in the developed final pattern, the total width was 'C/2+5.5cm', and the front was set at 1cm bigger in the size difference of the front and back. The width of the front neck and the back neck was set identically at 'C/12', while the width of the front neck was set to 'C/12+1.5cm'. For the armhole depth, we added 'C/4+2cm', and '0.5cm and 1.5cm' for the width of the front and back to anthropometry. The results of the try-on evaluation through 3D-Simulation indicated that the fitness of the final slim-fit dress shirt pattern was superior to available slim-fit dress shirt patterns on the market and evaluated as superior to the types for middle-aged men.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.117-141
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• 2001

From documentary comparative study on the chief virtues of the Back-Su(兪) points and the Front-Mo(募) points, the following results are obtained : 1. Contrast the Back-Su(兪) points with the Front-Mo(募) points, the needle-steadying depth of the Front-Mo(募) points is deeper than that of the Back-Su(兪) points. and Moxibustion dosage of the Front-Mo(募) points is more than that of the Back-Su(兪) points. 2. In the case of Kimun(LR14) and Kansu(BL18), Kergwol(CV12) and Shimsu(BL15), Chungwan(CV12) and Wisu(BL21), Kyungmun(GB25) and Shinsu(BL23), the Back-Su(兪) points can be chiefly used for the treatment of acute disease, external disease, exess disease and Jang(臟)-disease. contrary the Front-Mo(募) points can be chiefly used for the treatment of chronic disease, internal disease, deficiency disease and Bu(腑)-disease. 3. In the case of Kwangwon(CV4) and Sojangsu(BL27), Serkmoon(CV5) and Samchosu(BL22), Changmun(LR13) and Bisu(BL20), Chungbu(LV1) and Pesu(BL20), Chungguk(CV3) and Banggwangsu(BL28), the Front-Mo(募) points can be used for the treatment of unbalanced visceral funtion. contrary the Back-Su(兪) points can be used for not only the treatment of unbalanced visceral funtion but also the treatment of attached organs. 4. The Back-Su(兪) points can be used for the treatment of acute disease, external disease, exess disease, Jang(臟)-disease and attached organs-disease. contrary the Front-Mo(募) points can be chiefly used for the treatment of chronic disease, internal disease, deficiency disease, and Bu(腑)-disease.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.273-278
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• 2011

This paper has proposed a dual-band transmitter RF Front-end for IMT-Advanced systems which has been implemented in a 0.13-${\mu}m$ CMOS technology. The proposed dual-band transmitter RF Front-End covers 2300~2700 MHz, 3300~3800 MHz frequency ranges which support 802.11, Mobile WiMAX, and IMT-Advanced system. The proposed dual-band transmitter RF Front-End consumes 45 mA from a 1.2 V supply voltage. The performances of the transmitter RF Front-End are verified through post-layout simulations. The simulation results show a +0 dBm output power at 2 GHz band, and +1.3 dBm output power at 3 GHz band.

• Journal of Environmental Science International
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• v.31 no.12
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• pp.1069-1078
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• 2022

This study investigated the weather conditions, fine particle concentration, and ion components in PM_2.5 when two cold fronts passed through Busan in succession on February 1 and 2, 2021. A analysis of the surface weather chart, AWS, and backward trajectory revealed that the first cold front passed through the Busan at 0900 LST on February 1, 2021, with the second cold front arriving at 0100 LST on February 2, 2021. According to the PM₁₀ concentration of the KMA, the timing of the cold front passage had a close relationship with the occurrence of the highest concentration of fine particles. The transport time of the cold front from Baengnyeongdo to Mt. Gudeok was approximately 11 hours . The PM₁₀ and PM_2.5 concentrations in Busan started to increase after the first cold front had passed, and the maximum concentration occurred two hours after the second cold front passed. The SO₄^2-, NO₃^-, and NH₄⁺ concentration in PM_2.5 started to increase from 1100 to 1200 LST on February 1, after the first cold front passed, and peaked at 0100 LST to 0300 LST on February 2. However, the highest Ca²⁺ concentration was recorded 2-3 hours after the second cold front had passed.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.2
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• pp.106-113
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• 2008

The goal of crashworthiness is an optimized vehicle structure that can absorb the crash energy by controlled vehicle deformations while maintaining adequate space so that the residual crash energy can be managed by the restraint systems to minimize crash loads transfer to the vehicle occupants. Front side assembly is one of the most important energy absorbing components in relating to the crashworthiness design of vehicle. The structure and shape of the front side assemblies are different depending on auto-makers and size of vehicles. Thus, it is not easy to grab an insight on designer's intention when you glance at a new front side member without experiences. In this paper, we have performed the explicit nonlinear dynamic finite element analysis on the front side assembly of a passenger car to investigate the effect of thickness distribution of the front side assembly on the collapse shape, which is important in the aspect of controlling deformation to maintain adequate space, from the viewpoint of reverse engineering. To do this, we have performed crash FE analysis for the assembly by varying the thickness distribution of the assembly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.289-296
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• 2002

Using results obtained from field surveys in the outflow region of the Keum River in winter (February 22), spring (May 9), summer (July 31) and autumn (October 17) in 2000, it was described the nutrient front relating to the hydrography. It showed that the horizontal gradients was sharp in the distributions not only in salinity but also in nutrients in the region of the mouth of estuary far away about 20 km from the dyke of the Keum River during the year. The two layer structure was a ubiquitous feature in the inner estuarine side of the region showing the maximum horizontal gradients in salinity and nutrients. Although the absolute values in salinity and nutrient concentrations were distinguished by season, the nutrient front seperates the saltier and nutrients poor water in the open sea from the brackish and nutrients rich water of the plume. These results suggest that the nutrient front coincides with the esturine front in the region of freshwater influence (ROFI) of the Keum River.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.3
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• pp.91-105
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• 2004

Recently the function of a department store has changed to the concept of a multi-functional center because of the alternative stores such as discount stores, home shopping, and internet shopping. This means that the front plaza of a department store is not a personal or private space any more, but a public space. This study focuses on the special character of public space through the classification and preference types of department store front plazas. The major results of this study can be summarized as follows: (1) Components of front plaza of department store are classified by three factors. The first factor, named "space limit", has 14 elements ; the second, named "space decoration" has 16 elements ; third, named "activity", has 2 elements. The first preferred element is easily- used and easily- serviced wide space. The second preferred element is the equipment that is placed linearly along the street. The third preferred element is cultural events. (2) The comparison between the frequency and preference shows that the plazas could not satisfy the user-needs. (3) Preference factors of front plazas were examined to three characters such as familiarity, peculiarity, and openness. Familiarity, peculiarity, openness have a positive correlation in all types. Peculiarity especially influences the other two space - preference factors.

• Journal of the Korean Society of Costume
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• v.45
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• pp.17-28
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• 1999

This study was to analyze factors of the body form and factors of bodice pattern through a surface developement figure for the tight bodice pattern design. Fifty replicas of the trunk surface were made by applying a surgical tape method of female subjects between 18 and 24 years old. The result was as follows: 1. The gaps between direct measurements and measurements of the surface development figure were regarded as allowances for the tight bodice pattern. 2. There are four factors of body form selected by factor analysis. The 1st factor signifies th degree of fatness in the upper body. The 2nd factor signifies the length of the upper body. The 3rd factor signifies the part of the front shoulder. The 4th factor signifies the part of the neck. 3. There are high correlations between center back line of the surface development figure and back length line side line front length line back neck depth back upper chest depth. There are high correlations between back bust line of the surface development figure and back interscye breadth line back upper chest line back armhole line. There are high correlations between front bust line of the surface development figure and front upper chest line front interscye breadth line front armhole line front neck breadth 4. The regression expressions of measurements of the surface development figure of the upper body were analyzed as(Fig. 3).