• Structural Engineering and Mechanics
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• 제36권4호
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• pp.447-461
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• 2010

Fiber reinforced polymer (FRP) bars have been widely used as reinforcement for concrete structures. However, under elevated temperatures, the difference between the transverse coefficients of thermal expansion of FRP rebars and concrete may cause the splitting cracks of the concrete cover. As a result, the bonding of FRP-reinforced concrete may not sustain its function to transfer load between the FRP rebar and the surrounding concrete. The current study investigates the cracking resistance of FRP reinforced concrete against the thermal expansion based on a mechanical model that accounts for the tensile softening behavior of concrete. To evaluate the efficacy of the proposed model, the critical temperature increments at which the splitting failure of the concrete cover occurs and the internal crack radii estimated are compared with the results obtained from the previous studies. Simplified equations for estimating the critical temperature increments and the minimum concrete cover required to prevent concrete splitting failure for a designated temperature increment are also derived for design purpose.

• 한국의류학회지
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• 제27권6호
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• pp.665-674
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• 2003

The purpose of this study was to develop a grading increment at armhole area by apparel CAD(Computer Aided Design) system. In developing a grading increment at armhole area, we analyzed ease values of armhole area in bodice and sleeve by manual drafting patterns of five sizes. We suggested grading increments applied Pythagorean theorem to development the grading increment of the armhole of sleeve. The results and discussions of this study were as follows: 1. In drafting each size, the ease values were not identical. It was difficult to draft perfectly the same armhole line shape between sizes. 2. According to our developed grading increments applied Pythagorean theorem, the ease values were identical between sizes and difference of the armhole length between sizes was also identical. 3. The grading formulas were made out for apparel CAD system. Once grading increment or formula is set in the computer, it can be easily altered to various clothing items at any time. The efficiency of grading work will be also improved and grading time will be reduced.

• 한국식품영양학회지
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• 제24권1호
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• pp.71-78
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• 2011

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and for different times(0, 10, and 20 min at $90^{\circ}C$) for blanching over a 6 month period. Analyses were conducted for moisture content, total sugar content, browning index, polyphenol compounds, PPO activity, and SEM. Moisture content and PPO activity were increased by storage time. The increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. The Browning index was increased by storage time, and increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. Scanning electronic microscopy(SEM) studies were performed on peeled chestnuts. Results showed that the wrinkle structure of the cell wall was enhanced by storage time, and the level of enhancement was higher at $-10^{\circ}C$ than at $-20^{\circ}C$.

• 대한수학회지
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• 제36권4호
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• pp.679-679
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• 1999

• 한국토양비료학회지
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• 제9권3호
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• pp.201-210
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• 1976

Only 22.7% of total land area is arable land in Korea, it is anticipated that the increased land utilization of present arable land and enlargement of arable land through the reclamation of hillside and tidal land will be of great importance for the support of increased population in the future. Followings are the prediction of increased land utilization ratios, increased arable land through the reclamation of hillside and tidal land, and the increase] in fertilizer demand up to the year of 2000. 1. On the assumption that irrigation facilities, farm mechanization, and cropping systems would be improved remarkably by the year of 2000, the land utilization ratios of paddy land and upland are estimated to be 179% and 193% respectively. 2. Increments of fertilizer demand due to increased land utilization ratios, are estimated to be 2, 290 M/T in 1980, 70, 611 M/T in 1990, and 153, 619 M/T in 2000, when the amounts of fertilizers per unit area are fixed at present lrevels. 3. Increments of fertilizer demand due to the expansion of arable land through the reclamation of 516,330 ha of hillside land and 160,568 ha of tidal land, which are the present estimation of the reclaimable areas, are estimated as 32,960 M/T in 1980, 136,320 M/T in 1990, and 366,861 M/T in 2000. 4. Total increments of fertilizer demand due to the increased land utilization of arable land and the expansion of arable land through the reclamation of hillside and tidal lands in 2000's are estimated as 196,285 M/T for N, 147,351 M/T for $P_2O_5$, and 176,844 M/T for $K_2O$.

• 한국의류산업학회지
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• 제13권6호
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• pp.934-942
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• 2011

This study was intended to analyze conventional grading increments and methods for middle-age men's pants, and to suggest new grading guidelines that will enable to improve satisfaction with size and silhouette as a result of combining the concept of grading, which help maintain the ratio and proportion by sizes as one of ready-made apparel's advantages, with body form oriented and aesthetic approaches. In the apparel industry, the current sizing specifications and methods adopted by relevant companies, as well as the characteristics of body forms of men aged 35 to 55 years were comparatively analyzed to find out problems and ultimately to suggest their solutions or improvements. It was considered that as the conventional grading practices used in the industry were customary on the basis of the past experiences, it was required to take the body forms of target consumers into account and also, to reconsider the conventional grading methods. Analyses of sizing and specifications by brands show that 4 to 19 sizes including 82 or 84 as standard size have been produced. Since men's apparel has a large number of sizes with the large range of sizes, grading is critically important. As silhouettes depend on the distribution of grading rule values at each point of increment pattern in the main regions during grading, it is necessary to consider both size grading and form variations. To maintain an appropriate silhouette with keeping the angle of center back line of a pattern, it is desirable to set the ratio of side line part to center part from the crease line to approximately 3:7. It is required to diversify the values of grading rules according to different sizes and pattern regions in consideration for the body forms of key consumers. In addition, if the natural lines of designs and patterns for the width increments of waist circumference and hip circumference, the increments of hip width in pant's front and back panels, the ratio of grading rule values of the right and left sides of crease line, knee circumference, thigh circumference and so on are taken into account, grading will be satisfactory in the all aspects of size, silhouette and ratio.

• 한국산학기술학회논문지
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• 제16권10호
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• pp.6846-6851
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• 2015

본 연구에서는 성토체의 확장에 의해 성토체 하부지반으로 전달되는 연직응력 증분량을 계산할 수 있는 식을 탄성론에 근거하여 유도하였다. 연직응력 증분량 산정식의 유도과정에서는 평면기점의 개념을 적용하여 유도과정을 단순화하였다. 연직응력 증분량 산정식에 의한 계산결과를 수치해석결과와 비교해 보았을 때 성토체 하부지반으로의 깊이가 커질수록 산정식과 수치해석결과 사이의 차이가 감소하였다. 수평방향 거리에 따른 연직응력 증분량을 수치해석결과와 산정식에 의한 결과를 통해 비교해 볼 때 대체적으로 산정식에 의해 예측된 연직응력 증분량이 수치해석에 의한 증분량보다 약간 커서 보수적인 결과를 보임을 알 수 있었다.

• 한국식품영양학회지
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• 제20권1호
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• pp.40-46
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• 2007

본 연구는 건강지향적인 식품 소재로서 기능성과 효능을 지닌 동충하초를 이용하여 먹기 편한 젤리를 제조하기 위해 동충하초 분말을 각각 0%, 0.5%, 1%, 1.5%, 2% 첨가하여 만든 동충하초 젤리의 일반성분, 무기질 함량, 색도, 물성 및 관능평가를 실시한 결과는 다음과 같다. 동충하초 젤리의 일반성분 함량에서 수분 함량과 조단백질 함량은 동충하초 분말을 첨가한 군에서 높게 나타났으며(p<0.05), 반면에 조지방 함량은 대조군이 가장 높고 동충하초 분말 첨가군이 낮게 나타났다. 무기질 함량은 동충하초 분말을 첨가한 군이 대조군보다 칼슘, 마그네슘 및 칼륨 함량이 높았다(p<0.05). 색도 검사에서 L값과 a값은 대조군에 비해 동충하초 분말을 첨가한 군에서 낮아지는 경향이었으며 b값은 대조군이 가장 낮게 나타났다. 조직감은 대조군에 비해 동충하초 분말을 첨가한 군에서의 Hardness, Gumminess 및 Chewiness가 낮아지는 경향이었다. 관능검사에서는 동충하초 분말 1% 첨가군에서의 색, 맛, 질감 및 전체적인 기호가 높게 평가되었다. 이상의 연구결과를 통해 건강지향적인 기능성 식품 소재로서 기호성과 이용성을 증대시킬 수 있는 동충하초 젤리의 동충하초 분말 첨가량은 1% 첨가군이었으며 겔화제와 같은 첨가물에 따른 동충하초 젤리의 관능평가에 대한 연구가 지속적으로 이루어져야 된다고 사료된다.

• 한국농공학회논문집
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• 제60권5호
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• pp.69-80
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• 2018

This study investigated climate change influences over crop water requirement (CWR) and irrigation water requirement (IWR) of the wheat-rice cropping system of Upper Chenab Canal (UCC) command in Punjab Province, Pakistan. PRECIS simulated delta-change climate projections under the A1B scenario were used to project future climate during two-time slices: 2030s (2021-2050) and 2060s (2051-2080) against baseline climatology (1980-2010). CROPWAT model was used to simulate future CWRs and IWRs of the crops. Projections suggested that future climate of the study area would be much hotter than the baseline period with minor rainfall increments. The probable temperature rise increased CWRs and IWRs for both the crops. Wheat CWR was more sensitive to climate-induced temperature variations than rice. However, projected winter/wheat seasonal rainfall increments were satisfactorily higher to compensate for the elevated wheat CWRs; but predicted increments in summer/rice seasonal rainfalls were not enough to complement change rate of the rice CWRs. Thus, predicted wheat IWRs displayed a marginal and rice IWRs displayed a substantial rise. This suggested that future wheat production might withstand the climatic influences by end of the 2030s, but would not sustain the 2060s climatic conditions; whereas, the rice might not be able to bear the future climate-change impacts even by end of the 2030s. In conclusion, the temperature during the winter season and rainfall during the summer season were important climate variables controlling water requirements and crop production in the study area.

• 방사선산업학회지
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• 제9권1호
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• pp.1-7
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• 2015

The trend of x-ray image sensor has been evolved from an amorphous silicon sensor to a crystal silicon sensor. A crystal silicon X-ray sensor, meaning a X-ray CIS (CMOS image sensor), is consisted of three transistors (Trs), i.e., a Reset Transistor, a Source Follower and a Select Transistor, and a photodiode. They are highly sensitive to radiation exposure. As the frequency of exposure to radiation increases, the quality of the imaging device dramatically decreases. The most well known effects of a X-ray CIS due to the radiation damage are increments in the reset voltage and dark currents. In this study, a pixel array of a X-ray CIS was made of $20{\times}20pixels$ and this pixel array was exposed to a high radiation dose. The radiation source was Co-60 and the total radiation dose was increased from 1 to 9 kGy with a step of 1 kGy. We irradiated the small pixel array to get the increments data of the reset voltage and the dark currents. Also, we simulated the radiation effects of the pixel by MCNP (Monte Carlo N-Particle) simulation. From the comparison of actual data and simulation data, the most affected location could be determined and the cause of the increments of the reset voltage and dark current could be found.