• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.13-17
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• 2006

Dense and periodic arrays of holes and tungsten none dots were fabricated on silicon oxide and silicon. The holes were approximately 25 nm wide, 40 nm deep, and 60 nm apart. To obtain nano-size patterns, self-assembling resists were used to produce layer of hexagonally ordered parallel cylinders of polymethylmethacrylate(PMMA) in polystyrene(PS) matrix. The PMMA cylinders were degraded and removed with acetic acid rinse to produce a PS mask for pattern transfer. The silicon oxide was removed by fluorine-based reactive ion etching(RIE). Selectively deposited tungsten nano dots were formed inside nano-sized trench by using a low pressure chemical vapor deposition(LPCVD) method. Tungsten nano dot and trenched silicon sizes were 26 nm and 30 nm, respectively.

• Journal of Korean Society of Forest Science
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• v.17 no.1
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• pp.17-22
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• 1973

A study on the wood quality from planted Pinus koraiensis Sieb. et Zucc. has been undertaken by the University Forest in order to gain results of the gross structural features of stem. For this study some groups of trees were felled and several characteristics such as the degree of stem, slenderness, eccentric growth, heartwood diameter, height of butt sweep and butt-swell were analyzed. The results of the study are as follows. 1) The relation between diameter of log and its height in sample trees are nearly parallel to each other. But their degrees of slenderness in logs cut from intermediate and codominant trees are some what gentle as compared with that of logs from dominant tree. 2) The eccentric growth at transverse section of sample trees is generally decreased with the increase of tree height on all sample trees. 3) On the eccentric growth at transverse section of tree, a rather distinct tendency was noticed that all of sample trees showed the direction of eccentric growth in $R_2$ side. 4) Heartwood diameter appeares to become larger as tree growth decrease under same diameter of logs and log diameter in which heartwood appeares is larger in rapid growth rate trees. 5) The maximum height of butt-sweep generally shows that the larger the breast height diameter of tree is, the smaller its height becomes. On the contrary it was noticed that the larger the breast height diameter of trees, the higher the maximum height of butt-swell became. The direction of butt-sweep and butt-swell were shown in $R_1$ side in all sample trees.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.403-405
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• 1984

Since chlorella was found to be a source of protein in 1974, wide ranges of investigations on culture methods, its constituents and nutritional factors have been carried out, i. e. most of them were the reports on the nutritional evaluation. However, kinetics such as absorption, distribution, metabolism and elimination of chlorella protein have not been fully elucidated. So, on the assumption that using $N^{15}$ labelled chlorella protein could accomplish good results for kinetics of chlorella in in vivo experiments, $N^{15}$ was added to the culture fluid. From the result of this study, it is suggested that chlorella utilizes N as well as $N^{15}$ in protein synthesis, and this $N^{15}$ labelled chlorella protein can be useful tool for the study of kinetics of chlorella in in vivo experiments.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.371-376
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• 2017

The effect of vortex finder confiqurations on the PM-10 collection efficiencies has been investigated using 7 different types of cyclones. Cyclone inlet velocities were calculated by computational fluid dynamics analysis and PM-10 collection efficiencies were measured from experimental apparatus. The inlet velocities of normal, P and A type cyclones were calculated 15.48 m/sec, 16.03 m/sec and 15.9 m/sec, respectively while experimental results show that PM-10 collection efficiencies were increased 4% for P type and 7% for A type cyclones compared to normal cyclone. Also it was found that there exist optimum parallel head lengths for both P and A type cyclones to maximize the PM-10 collection efficiencies.

• Journal of the Korean Wood Science and Technology
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• v.6 no.1
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• pp.3-7
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• 1978

Quercus serrata degraded by Leminus edodes(berk) Singer was investigated. In order to evaluate on affect of the fungi on the sound logs, and the logs attacted for 2 years and five years were used as a sample tree. Large portions of carbohydrate mainly was decomposed by the fungy. It is supported by the increasing of alkaline extractives and the breaking up of crystallinity. Lignin is transformed considerably as shown the results of the determination of Klason lignin, gel filtration and nitrobezene oxidation. On the other hand, the decreasing of methoxyl group and the increasing of carboxyl group in parallel with demethlation and acidification are presented. Syringyl nuclei unit is decomposed easier than guaiacyl unit. It is also illustrated that the more decreasing of carboxyl group compared with aldehyde group was acidified biodegradation.

• Education of Primary School Mathematics
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• v.20 no.4
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• pp.305-319
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• 2017

In the process of finding the triangle height, 26 students in the 6th grade were surveyed to understand the students' triangle height through the eye movement data and to investigate the cognitive load of the students. As a result, the correctness rate of the pre-test was significantly increased in the post-test, and the frequency and retention of gaze data were smaller in the post-test than in the AOI of each question. The Participants's subjective cognitive load indicated that it was more difficult to understand the concept of rotated triangles compared with upright triangles that were parallel to the ground. More frequent and more retentions in the eye-tracking data were detected in the right triangles and acute triangles by rotating configuration. Eye movement data show that eye tracking technology can provide an objective measure of students' cognitive load for feedback on instructional design.

• 한국해양학회지
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• v.21 no.4
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• pp.203-210
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• 1986

A linear parallel transport model is formulated and applied to an idealized Yellow Sea, With this simple analytical model, the hither-to suspected upwind flow phenomena in the southern Yellow Sea can be reasonably explained. In deep waters where the local depth exceeds a critical depth (Hc=53m in the present model sea), pressure gradient force dominates over wind stress and contributes to an upwind flow. The estimated upwind flow velocity increases with wind speed and a maximum upwind flow occurs along the axis of the Yellow Sea embayment. For the typical south wind of 5-10 knots in summer, the upwind (southward) flow velocity along the axis of the Yellow Sea is estimated to be 1-5cm s$\^$-1/. While, for the typical north wind of 10-15 knots in winter, the upwind (northward) flow velocity is 5-12cm s$\^$-1/. These velocity ranges can be served as rough estimates for the intrusion velocity of the Yellow Sea Bottom Cold Water in summer and the Yellow Sea Warm Current in winter, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.1
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• pp.57-64
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• 2005

월동기간 동안 zoysiagrass[Zoysia matrella(L.) Merr]와 creeping bentgrass(Agrostis palustris Hunds)의 저온 스트레스에 대한 탄수화물 대사 반응을 구명하기 위해 11월부터 이듬해 4월까지의 식물체내의 탄수화물 대사산물의 변화를 비교 분석하였다. Creeping bentgrass의 녹색도와 뿌리 성장은 온도변화와 거의 평행하게 변화하였으나 zoysiagrass는 뿌리 성장에 거의 변화가 없이 3월 말까지 담황색을 나타냈다. 11월부터 이듬해 1월까지 zoysiagrass에서 glucose와 sucrose 함량은 크게 높았고, 1월에서 4월까지 starch를 제외한 모든 탄수화물 화합물들의 감소의 정도가 현저하게 낮았다. Reeping bentgrass에서 fructan의 depolymerization이 2월 이후 단당류와 이당류의 감소와 일치했으나 zoysiagrass에서는 starch 가수분해가 11월부터 일찍이 시작되었다. 이상의 결과들은 creeping bentgrass와 비교 했을때 zoysisagrass 뿌리의 높은 비구조적 탄수화물의 농도가 저온 내성과 밀접한 관계가 있음을 잘 나타내어 주고 있다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.219-222
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• 2007

In this paper, we have designed microstrip antenna of 800[MHz] band. It will be able to integrate TRS(Trunked Radio System), GSM(Global System for Mobile telecommunication) band including the CDMA(Code Division Multiple Access) band. we designed repeater and a base station antenna which is possible at the ship and marine of safety. It is improves a narrow bandwidth problem of microstrip antenna. It had L-shaped feeding structure at a rectangular patch and added the parallel L-slot that used a duplex resonance effect. Also for the improvement of profit the stack with the perpendicular. Designed frequency bandwith(VSWR 2:1) of the antenna showed good characteristic of 789${\sim}$1046[MHz] to 292[MHz](36%). Also the E-plan and H-plan all profit 6.4[dBi] above, the 3[dB] beam width showed the characteristic over the E-plan $44.7^{\circ} and H-plan $61.8^{\circ} to be improved.

• Korean Journal of Optics and Photonics
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• v.9 no.6
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• pp.362-367
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• 1998

Center Distance Finding (CDF) is a technique to find the sphere diameter by measuring the distance between two contacting spheres. The focal spots of the sphere clusters are formed in the back-focal plane by the transmission-mode optical microscope with the pseudothermal illumination source. Digital images taken by the CCD camera were processed by the software called Global Lab Image. The centers of the focal spots are found and the spot positions are expressed in terms of the CCD pixel elements, whose coordinate are calibrated by a heterodyne interferometer. The new CDF measurement system has been developed, which are more advantageous in time and convenience than the existing system, while the measurement uncertainly remains sufficient for its use as a magnification standard for optical microscopy. Two kinds of polystyrene spheres whose nominal diameters 3 and 10 $\mu\textrm{m}$ (NIST SRM 1962 and 1960) are measured with the uncertainly less than 1% at the confidence level of 99%, and the results are compared with the results of National Institute of Standards and Technology.