• 한국진공학회지
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• 제22권5호
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• pp.262-269
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• 2013

집속 이온빔 장비는 나노크기의 패턴을 제작하는 한 방법이지만, 정밀한 제작은 쉽지 않다. 그러므로 집속 이온빔 장비로 샘플을 제작할 때 고려해야 하는 공정 조건을 정리하여 초보자도 샘플제작이 가능하도록 도움을 주고자 한다. 본 장비로 원하는 나노크기의 패턴을 제작하기 위해서 집속 이온빔 장비의 공정변수들을 최적화 하는 과정이 중요하다. 가공할 때 고려해야 하는 변수에는 빔 전류량(빔 크기)과 도즈(빔 지속시간)가 있다. 도즈를 결정한 후에 패턴을 제작하는데 걸리는 시간과 패턴의 크기를 고려하여 빔 전류량을 선택하면 된다. 여기서 도즈는 제작하려는 나노크기의 패턴의 금속 두께에 따라 결정이 된다. 이 논문에서 최적화한 1 pA의 빔 전류와 $0.1nC/{\mu}m^2$의 도즈의 공정조건에서 100 nm 두께의 금 박막 위에 타원형의 구멍을 정밀하게 제작할 수 있다.

• 한국잠사곤충학회지
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• 제34권2호
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• pp.52-57
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• 1992

견의 저온염색용 조제(K-1)를 사용하여 염료 농도, 염욕의 pH, 염색시간에 따른 염색속도를 구하여 이 저온염색용가 염색에 미치는 영향을 분석한 결과를 다음과 같이 요약한다. 1. pH 7에서 K-1의 농도가 증가할수록 무첨가구에 비해 흡진율은 증가 하였으며, K-1의 농도가 3% o.w.f. 이상에서는 증가의 경향이 둔화되었다. 2. pH 5에서도 무첨가보다 K-1의 첨가구에서 높은 흡진율을 보였으며, pH 7의 5$0^{\circ}C$ 첨가구가 pH 5, 5$0^{\circ}C$의 무첨가구보다 확산성은 높게 나타났다. 3. 염료 농도별로 볼 때 pH 7과 pH 5에서 모두 K-l 첨가구에서는 무첨가구보다 흡진율이 클 뿐만 아니라 염료 농도에 따른 흡진율 감소가 적게 일어났다.

• 한국작물학회지
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• 제33권s01호
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• pp.1-17
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• 1988

Rice Quality is considered to the five catagories ; the nutritional value: the characteristics of cooking. eating and processing: grain size, shape and appearance : milling yields: and storage characteristics. Because most rice is processed and consumed in whole-kernel form. the cooking and eating quality is of important and the physical properties of the intact kernel such as size, shape and general appearance are of particular significance in determining marketing quality. Eating Quality which can be directly evaluated by consumer's panel test is so complicate and variable, and thus the objective and simplified method of evaluation is required of using appropriate instruments. Even though many researches have been done to evaluate the eating quality in various aspects such as the texture of cooked rice kernels, amylogram analysis of rice powder, amylose content. gelatinization temperature. moisture absorption of rice kernel, and cooking characteristics, none of them is satisfied for the evaluation of eating quality. The improving eating quality should be also considered to many cultural factors. such as varieties, climatic and soil conditions, cultural method, handling after harvest. milling and storage conditions. In Korea, many researches in grain size. shape and appearance, and eating quality have been done with the varietal improvement mainly by rice breeders, but no effective method of evaluation was established. A few research have been done in the relationship between rice quality and cultural factors. In the future, research in rice quality should emphasize to establish the standard evaluation method in the physicochemical properties of rice kernels for application of varietal selection. and to develop cultural practices for the preserving quality characteristics of the varieties.

• 한국농촌생활과학회지
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• 제7권1호
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• pp.31-37
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• 1996

This experiment was carried out in order to investigate milling methods of rice flours on characteristics of rice-cinnamon cakes. The expansion ratio and cake volume of hydrated rice flour was the better than the non-hydrated rice flours. The rice-cinnamon cake of the hydrated riceflour was generally alike in texture and taste to the cake of wheat flour as the result of Instron and sensory evaluation. The rice - cinnamon cake of the non - hydrated rice flour was generally lower in aircell and texture to the cake of the hydrated rile flour.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3289-3293
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• 2014

Femtosecond laser ablation (fs LA) was used in this study to identify pollution by heavy metals and the distribution of elemental nutrients at different rice milling ratios. Polished rice (degrees of milling of 3, 5, 7, 9, and 11) was collected from major Korean supermarkets and one sample thereof was selected. An internal quality control experiment was conducted using a rice flour certified reference material from the Korea Research Institute of Standards and Science (KRISS CRM) for the evaluation of the efficacy. To assess the effectiveness of the analysis method, the reliability was validated using a food analysis performance assessment scheme (FAPAS), with chili powder serving as an external quality control. The results of the analysis of the inorganic elements Ti, Ca, Al, Fe and Mn in white and brown rice with degrees of milling of 3, 5, 7, 9 and 11 using ICP-MS, ICP-OES and AAS revealed contents of 0.40, 49.2, 2.43, 5.36 and 10.3 mg/kg in white rice and 0.59, 78.0, 7.52, 11.0 and 18.5 mg/kg in brown rice, respectively. Among the elements, there were remarkable differences in the measured contents. By comparing the contents of the elements at different degrees of milling, Ti, Co, As, Ca, Al, Cu, Fe, and Mn were determined to be distributed on the surface of the rice grains, whereas the contents of Cd and Pb increased toward the center of the rice grains, and Si was evenly distributed. After the quantitative analysis of rice samples polished to different degrees of milling, Ca and Al, which were contained in large amounts, and Si were analyzed with specificity by fs LA. The results show that Ca and Al were distributed in the rice husk (protective covering of rice) and Si was distributed in all parts of the rice.

• Journal of Biosystems Engineering
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• 제4권1호
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• pp.76-86
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• 1979

This study was conducted to find out the effects of rainfall occurring during the paddy sun-during process of traditional paddy harvesting operations on the quality of milld rice. Rice varieties used for the experiment were MINEHIJARI variety a japonica and SUWEON 264 vareity , a sister-line of TONG-IL . Sun-drying days after the paddy cutting, times of storm occurrance during sun-drying period, and storm duration were treated as variables. The results is summarised as follows : 1. Brown rice recovery exposed to rainfall during the sun-druing period were ranged 81.6-82.1% and 79.4-80.2% for MINEHIKARI and SUWEON 264 varieties, respectively. which showed negligible effect by rainfall. 2. Milling recovery of MINEHIKARI variety was not affected by storm duration but by the by the sun-drying days after cutting as the sun-drying days increased to eight and four days when the variety met the rainfall one and two times, respectively. The range of milling recoveries of MINEHIKARI variety were 75.18-74.07% and 75.24-73.46% as the variety met the rainfall one and two times, respectively, and it were estimated that up to 0.9% and 1.5% of milling recovery would be reduced by one and two times of rainfall during sun-drying period. 3. The milling recovery of SUWEON 264 variety was affected only by the increase of drying days after cutting when it met one time of rainfall during the sun-drying period, while it was begun to reduce by the storm duration more than 11hours as the drying paddy met two times of rainfall. The milling reveries of the paddy met one and two times of rainfall were ranged 74.24-73.21% and 74.02-72.36% which were estimated to be reduced up to 0.9 % and 1.8% by the increase of the drying days after cutting and storm duration , respectively. 4. The head rice recovery of MINEHIKARI rice variety showed notable decrease as the drying days after cutting increased, and also it was greatly reduced even by the five hours of storm duration when one time of rainfall occurred but it was not affected by storm duration when the rainfall occurred two times. Head rice recoveries of MINEHIKARI met one and two times of rainfall during the sun-drying period were 65. 15 -40.85% and 61.86 - 30.03 %, which showed terrible reduction as much as up to 25% and 35% compared to that which did not met rainfall during the sun-drying process. 5. Head rice recovery or SUWEON 264 variety was very much reduced as the sum-drying days after cutting increased. Storm duration less than five hours during the sun-drying process did not affect on the decrease of head rice recovery when the variety was exposed to one time of rainfall, while storm duration affected considerably on the reduction of head rice recovery of SUWEON 264 variety exposed to two times of rainfall. The range of head rice recovery, 56.43 - 33.94% and 51.28 - 21.03% , for the paddy exposed to rainfall one and two times were evaluated that up to 24% and 37% of reduction in head rice recovery would be brought about compared to the head rice recovery of the sundriedpaddy that did not met the rainfall.

• Journal of Biosystems Engineering
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• 제4권1호
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• pp.75-75
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• 1979

This study was conducted to find out the effects of rainfall occurring during the paddy sun-during process of traditional paddy harvesting operations on the quality of milld rice. Rice varieties used for the experiment were MINEHIJARI variety a japonica and SUWEON 264 vareity , a sister-line of TONG-IL . Sun-drying days after the paddy cutting, times of storm occurrance during sun-drying period, and storm duration were treated as variables. The results is summarised as follows : 1. Brown rice recovery exposed to rainfall during the sun-druing period were ranged 81.6-82.1% and 79.4-80.2% for MINEHIKARI and SUWEON 264 varieties, respectively. which showed negligible effect by rainfall. 2. Milling recovery of MINEHIKARI variety was not affected by storm duration but by the by the sun-drying days after cutting as the sun-drying days increased to eight and four days when the variety met the rainfall one and two times, respectively. The range of milling recoveries of MINEHIKARI variety were 75.18-74.07% and 75.24-73.46% as the variety met the rainfall one and two times, respectively, and it were estimated that up to 0.9% and 1.5% of milling recovery would be reduced by one and two times of rainfall during sun-drying period. 3. The milling recovery of SUWEON 264 variety was affected only by the increase of drying days after cutting when it met one time of rainfall during the sun-drying period, while it was begun to reduce by the storm duration more than 11hours as the drying paddy met two times of rainfall. The milling reveries of the paddy met one and two times of rainfall were ranged 74.24-73.21% and 74.02-72.36% which were estimated to be reduced up to 0.9 % and 1.8% by the increase of the drying days after cutting and storm duration , respectively. 4. The head rice recovery of MINEHIKARI rice variety showed notable decrease as the drying days after cutting increased, and also it was greatly reduced even by the five hours of storm duration when one time of rainfall occurred but it was not affected by storm duration when the rainfall occurred two times. Head rice recoveries of MINEHIKARI met one and two times of rainfall during the sun-drying period were 65. 15 -40.85% and 61.86 - 30.03 %, which showed terrible reduction as much as up to 25% and 35% compared to that which did not met rainfall during the sun-drying process. 5. Head rice recovery or SUWEON 264 variety was very much reduced as the sum-drying days after cutting increased. Storm duration less than five hours during the sun-drying process did not affect on the decrease of head rice recovery when the variety was exposed to one time of rainfall, while storm duration affected considerably on the reduction of head rice recovery of SUWEON 264 variety exposed to two times of rainfall. The range of head rice recovery, 56.43 - 33.94% and 51.28 - 21.03% , for the paddy exposed to rainfall one and two times were evaluated that up to 24% and 37% of reduction in head rice recovery would be brought about compared to the head rice recovery of the sundriedpaddy that did not met the rainfall.

• 한국분말재료학회지
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• 제16권5호
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• pp.363-369
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• 2009

The amorphization process and the thermal properties of amorphous Ti$_{40}$Cu$_{40}$Ni$_{10}$Al$_{10}$ powder during milling by mechanical alloying were examined by X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The chemical composition of the samples was examined by an energy dispersive X-ray spectrometry (EDX) facility attached to the scanning electron microscope (SEM). The as-milled powders showed a broad peak (2$\theta$ = 42.4$^{\circ}$) with crystalline size of about 5.0 nm in the XRD patterns. The entire milling process could be divided into three different stages: agglomeration (0 < t$_m$ $\leq$ 3 h), disintegration (3 h < t$_m$ $\leq$ 20 h), and homogenization (20 h < t$_m$ $\leq$ 40 h) (t$_m$: milling time). In the DSC experiment, the peak temperature T$_p$ and crystallization temperature T$_x$ were 466.9$^{\circ}C$ and 444.3$^{\circ}C$, respectively, and the values of T$_p$, and T$_x$ increased with a heating rate (HR). The activation energies of crystallization for the as-milled powder was 291.5 kJ/mol for T$_p$.

• 한국분말재료학회지
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• 제16권5호
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• pp.316-325
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• 2009

Fe based (Fe$_{68.2}$C$_{5.9}$Si$_{3.5}$B$_{6.7}$P$_{9.6}$Cr$_{2.1}$Mo$_{2.0}$Al$_{2.0}$) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The experiment results show that the as-prepared Fe amorphous powders less than 90 $\mu$m in size has a fully amorphous phase and its weight fraction was about 73.7%. The as-atomized amorphous Fe powders had a complete spherical shape with very clean surface. Differential scanning calorimetric results of the as-atomized Fe powders less than 90 $\mu$m showed that the glass transition, T$_g$, onset crystallization, T$_x$, and super-cooled liquid range $\Delta$T=T$_x$-T$_g$ were 512, 548 and 36$^{\circ}C$, respectively. Fe amorphous powders were mixed and deformed well with 10 wt.% Cu by using AGO-2 high energy ball mill under 500 rpm.

• 대한기계학회논문집A
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• 제24권8호
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• pp.2123-2130
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• 2000

Radial immersion ratio is an important factor to determine the threshold in face milling and should be estimated in process for automatic force regulation. In this paper, presented is a method of on-line estimation of the radial immersion ratio using cutting force. When a tooth finishes sweeping, sudden drop of cutting forces occurs. This force drop is equal to the cutting force that acts on a single tooth at the swept angle of cut and can be obtained from cutting force signal in feed and cross-feed direction. The ratio of cutting forces in feed and cross-feed directions acting on the single tooth at the swept angle of cut is a function of the swept angle of cut and the ratio of radial to tangential cutting force. In the research, it is found that the ratio of radial to tangential cutting force is not affected by cutting conditions and axial rake angle. Therefore, the ratio of radial to tangential cutting force determined by just one preliminary experiment can be used regardless of the cutting conditions. Using the measured cutting force and predetermined ratio, the radial immersion ratio is estimated. Various experiments show that the radial immersion ratio and instantaneous ratio of the radial to tangential direction cutting force can be estimated very well by the proposed method.