• Journal of Navigation and Port Research
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• v.33 no.10
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• pp.671-678
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• 2009

Recently, there have been some researches in the equipment fault detection based on shock and vibration information. Most research of them is based on shock and vibration monitoring to determine the equipment fault or not. Different with engine fault detection based on shock and vibration information we focus on detection of engine for boat and system control. First, it use the duplicated-checking method for shock and vibration information to determine the engine fault or not. If there is a fault happened, we use the integral to determine the error engine shock wave width and detect the fault area. On the other hand, we use the engine trend analysis and standard of safety engine to implement the shock and vibration information database. Our simulation results show that the probability of engine fault determination is 98% and the probability of engine fault detection is 72%

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.490-496
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• 2020

A styrofoam box is used as a simple and easy freezing method to preserve animal semen as a livestock genetic source. This study optimized the methods of freezing chikso brindled cattle semen. To test the freezing box, the motility of spermatozoa was compared between two box sizes (length×width×heigh) with the dimensions of 23.5×30.5×22.5 cm and 25.5×46.5×26.5 cm. The motility of thawed sperm from brindled Korean bulls was used to confirm the efficiency of the freezing boxes. The box having a larger inner space with larger horizontal and height measurements supported better motility after thawing (60.4±5.3% vs 67.2±3.1%) with 10 min of exposure time in liquid nitrogen vapor. The optimized freezing space is estimated to be an essential element for successful freezing results and the larger box could be used for production of more than 60 frozen semen straws. These properties are also helpful to optimize the cryopreservation techniques that would control the quality and quantity of semen straws according to different animal species.

• Ocean and Polar Research
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• v.32 no.4
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• pp.337-350
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• 2010

This study conducted sedimentological and geophysical surveys for 3 years (2006-2008) in southern Gyeonggi Bay, Korea to elucidate temporal changes in subaqueous dune morphology on a sand ridge trending northeast to southwest that has been excavated by marine sand mining. The sand ridge (~20 m in height, ~2 km in width and 3~4 km in length) has a steep slope on the NW side and a gentle slope on the SE side, creating an asymmetric profile. Large (10~100 m in length) and very large (>100 m in length) dunes occurring on the SE side of the ridge show a northeastward asymmetrical shape, whereas dunes on the NW side destroyed by marine sand mining display a southwestward asymmetry. The comparison between Flemming (1988)'s correlation and the height-length correlation of this study indicates that tidal current and availability of sand sediment are major controlling factors to the development and maintenance of dunes. Depth and sedimentary characteristics (grain size) are not likely to be major controlling factors, but indirectly influence dune growth by hydrological and sedimentary processes. The length and the height of dunes decrease toward the southeastern trough away from the crest of the ridge. These features result from the decrease of tidal current and sediment availability. The length and the height of dunes on the southeast side decrease gradually over time. This is a result of the interaction between tidal current and the decrease in sediment availability due to sediment extraction by marine sand mining. Marine sand mining has destroyed the dunes directly, causing irregular shapes of shorter length and lower height. The coarse fraction of suspended sediments is transported and deposited very close to the sand pit. By contrast, relatively fine sediments are transported by the tidal current and deposited over a wide range by the settling-lag effect, resulting in a decrease of sediment grain size in the area where suspended sediments are deposited. In addition, marine sand mining, decreases the height of dunes. Therefore, morphological and sedimentological characteristics of dunes around the sand pits will be significantly changed by future sand mining activities.

• The Korean Journal of Quaternary Research
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• v.9 no.1
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• pp.33-42
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• 1995

우리나라의 서해(West Sea)는 일명 황해(Yellow Sea)라고 일컬어지는 약 40여 m의 평균 수심을 갖는 대륙붕 해저지형 분지에 의하여 지배되는 전형적 육연해이다, 그런데 이 바다는 중심부(황해의 중심부)를 기준으로 하여 중국 대륙의 산동반도에서 양가강 하구에 이르는 서부 해안을 가지며 북부에는 발해만의 해안이 있고 동부에는 서해(황해) 특유의 넓 은 조수환경(tidal environment)과 조수해안이 발달한다. 그러나 남쪽으로는 북서태평양과 연결된다. 한국 서해안이 평균 4m 이상의 조차(tidal range)를 나타내는 조간대 조수환경이 며 조간대 해저지형(intertidal morphology)이 전형적인 퇴적층(체)에 의하여 지배되는 여러 가지 특징을 나타낸다. 서해안 조수환경은 네델란드, 독일 또는 지배되는 여러 가지 특징을 나타낸다. 서해안 조수환경은 네델란드 독일 또는 미국의 경우와 같이 연구가 잘되어 세계 적으로 널리 알려진 소위 barrier island system and tidal depositional environments와는 크 게 다른 퇴적과정과 환경이다. 경기도 남양만의 조수 환경의 경우, 조간대 해저지형 요소인 조류로(tidal channel)와 조간대 정규해저(intertidal zone proper)에 관한 동력적 퇴적과정 연 구결과 조간대 특유의 lateral sedimentation 과 vertical sedimentation 2가지 퇴적과정중 후 자의 퇴적과정이 우세한 것으로 밝혀졌고 이러한 퇴적과정의 진행이 매우 안정한 지속성을 가지는 것이 특징이다, 이러한 퇴적과정의 조간대 퇴적물의 쇄설 입자는 약 20% 미만의 모 래(sand) 입자 50~70%의 실트(silt) 와 점토(clay) 입자가 20~30%에 달하는 입자조직 (grain texture)의 퇴적상을 나타낸다. 결과적으로 조간대의 동력적인 조수수괴의 수위(level of tidal water)는 평균 만조선과 평균 저조선으로 한정되며 이것은 퇴적과정과 퇴적작용의 조정(control) 요인으로 조간대 퇴적상의 발달과 분포에 큰 영향을 미친다, 예를들면 남양만 등의 대부분의 서해안 조간대 표층 퇴적상(녁\ulcorner미 sedimentary faci-es)은 만조선에서 간조 선에 가까울수록 조립화현상(coarsening trend)을 나타낸다. 이러한 퇴적상 변화는 저조선에 서 만조선으로의 조간대 지형과 주조수로의 지형.수력학적 특성이 다음과 같기 때문이다. a) a general decrease in width b) a general decrease in depth c) a general decrease in maximum and average current velocities d) a general increase in contents of suspended mud e) a general decrease in grain size of the bottom sand and an increasing abundance of muddy deposits. 우리나라 서해안 조간대 퇴적층(체)의 수직 층서(vertical stratigraphy)는 지난 3여년동안의 수십개의 vibracoring(주상시추)에 의하여 매우 흥미롭고 중요하게 밝혀지고 있는바 이것은 현세(Holocene)와 선현세(preHolocene: 11000 years BP)의 오랜시간 경과에 따른 조수환경 변화의 수직퇴적 과정과 기후 해수면 변화의 현상에 원인이 있다고 해석된다.(박용안 외, 1992-1995)결과적으로 서해안 조수퇴적체(층)의 분지주변(basim margin)진화과정이 밝혀지 고 있다.

• Journal of the Korean Vacuum Society
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• v.12 no.3
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• pp.168-173
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• 2003

Recently, according to the rapid progress in Flat-panel-display industry, there has been a growing interest in the poly-Si process. Compared with a-Si, poly-Si offers significantly high carrier mobility, so it has many advantages to high response rate in Thin Film Transistors (TFT's). We have investigated a new process for the high temperature Solid Phase Crystallization (SPC) of a-Si films without any damages on glass substrates using thin film heater. because the thin film heater annealing method is a very rapid thermal process, it has very low thermal budget compared to the conventional furnace annealing. therefore it has some characteristics such as selective area crystallization, high temperature annealing using glass substrates. A 500 $\AA$-thick a-Si film was crystallized by the heat transferred from the resistively heated thin film heaters through $SiO_2$ intermediate layer. a 1000 $\AA$-thick $TiSi_2$ thin film confined to have 15 $\textrm{mm}^{-1}$ length and various line width from 200 to 400 $\mu\textrm{m}$ was used as the thin film heater. By this method, we successfully crystallized 500 $\AA$-thick a-Si thin films at a high temperature estimated above $850^{\circ}C$ in a few seconds without any thermal deformation of g1ass substrates. These surprising results were due to the very small thermal budget of the thin film heaters and rapid thermal behavior such as fast heating and cooling. Moreover, we investigated the time dependency of the SPC of a-Si films by observing the crystallization phenomena at every 20 seconds during annealing process. We suggests the individual managements of nucleation and grain growth steps of poly-Si in SPC of a-Si with the precise control of annealing temperature. In conclusion, we show the SPC of a-Si by the thin film heaters and many advantages of the thin film heater annealing over other processes

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.53-59
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• 1986

The effects of soil moisture on seasonal changes of photosynthesis, transpiration and stomatal resistance were studied in sorghum (Pioneer 931) and sorghum - sudangrass hybird (Pioneer 988) at Suweon in 1985. Soil moisture was maintained with approximately 100, 80, 60 and 40% of field moisture capacity in large concrete pot (12m length $\times$ 1m width $\times$ 1m depth). 1. Photosynthesis and transpiration showed a sharp seasonal changes and reacted similarly to water stress and environmental factors, and were the highest in the middle of August, and were the lowest in the beginning of October. Sorghum - sudan hybird had better photosynthesis, transpiration and stomatal control than those of sorghum in hot summer season. 2. The rate of photosynthesis of 60 and 80% field moisture capacity was higher than that of 100 and 40% throughout growing season, but the effect of soil moisture on photosynthesis varied seasonally by climate factors. Optimum soil moisture was 60% in early summer and fall, and was 60 - 80% in hot summer season. 3. Drought and over-moisture affected physiological metabolism of plant, and so the dry matter yield of 40 and 100% field moisture capacity decreased by 70% compared with that of 60% field moisture capacity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.31-35
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• 2015

This experiment was carried out to breed a very early-maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in the Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan, Korea from 2012 to 2014. New variety "Greenfarm3ho" is a diploid variety with a green leaf color, a semi-erect growth habit in late autumn/fall, and an erect growth habit in early spring. With a heading date of April 27, Greenfarm3ho was categorized as an early-maturing variety. Compared with the "Greenfarm" control variety, Greenfarm3ho's flag-leaf width was narrower by 0.5 mm, its flag-leaf length was longer by 4.4 cm, and its plant length was longer by 3 cm; additionally, Greenfarm3ho's stem thickness was 0.1 mm thicker and it showed winter hardiness. The dry matter (DM) yield (8,976 kg/ha) of Greenfarm3ho was similar to that of Greenfarm. The in vitro dry matter digestibility (IVDMD), total digestible nutrient (TDN), and crude protein (CP) of Greenfarm3ho were 70.0%, 64.1%, and 1.0%, respectively, which are higher than those of Greenfarm by 2.9%, 2.0%, and 1.4%, respectively. The acid detergent fiber (ADF) and neutral detergent fiber (NDF) content of Greenfarm3ho were 31.4% and 53.3%, respectively, which are lower than those of Greenfarm by 2.5% and 3.0%, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.1
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• pp.9-14
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• 2011

This experiment was carried out to breed a very early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2009 to 2010. A new variety, 'Green farm' is a diploid variety with green in leaf color and has erect and semi-erect growth habit in late autumn and early spring, respectively. 'Green farm' was on 28 April in heading date as a early-maturing variety. 'Green farm' was also wider by 0.4 mm in flag leaf width, longer by 0.8 cm in flag leaf length and shorter by 5 cm in plant height than those of control variety, 'Florida 80', respectively. 'Green farm' was thicker in stem thickness and stronger in winter hardness than those of the 'Florida 80'. Dry matter (DM) yield (11,790 kg/ha) of 'Green farm' was similar to that of 'Florida 80'. In vitro dry matter digestibility (IVDMD), total digestible nutrient (TDN) and crude protein (CP) of 'Green farm' were 68.7, 63.3 and 10.3% which are 1.9, 1.7 and 0.6% higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green farm' were 32.5 and 54.6% which are 2.2 and 4.3% lower than those of the 'Florida 80', respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.10-14
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• 2013

This experiment was carried out to breed an early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in the Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2009 to 2011. A new variety, 'Green farm II' is a diploid with green leaves and has a semi-erect growth habit in late autumn and erect growth habit in early spring, respectively. 'Green farm II' was on the $28^{th}$ of April in the heading date as an early-maturing variety. 'Green farm II' was also wider by 0.6 mm in flag leaf width, shorter by 1 cm in flag leaf length and shorter by 1 cm in plant length than those of the control variety, 'Florida 80', respectively. 'Green farm II' was thicker by 0.7 mm in stem thickness and strong in winter hardness. Dry matter (DM) yield (11,452 kg/ha) of 'Green farm II' was similar to that of 'Florida 80'. In vitro dry matter digestibility (IVDMD), total digestible nutrients (TDN), and relative feed value (RFV) of 'Green farm II' were 70.6%, 63.9%, and 114% higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green farm II' were 31.7% and 52.6% which were 3.5% and 6.4% lower than those of 'Florida 80', respectively.

• Journal of Korea Water Resources Association
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• v.49 no.2
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• pp.83-94
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• 2016

Geomorphological, bed material and hydraulic characteristics are basis informations for the planning, design and management of the river in the aspect of flood control and environmental conservation, and it is very important to use these informations for the design of stable channel. In this study, dominant discharge was selected, geomorphological and hydraulic characteristics were analyzed using that discharge and also the characteristics of bed materials distribution were analyzed and bed materials-flow resistance relationship was evaluated, for the upstream section of Namgang dam. The dominant discharge was estimated a return period of approximately 1.5 year and stream type were classified Segment 1 and Segment 2 in this stream. Also, the frequency of riffle-pool showed 4.4 because this study area has the characteristics of natural channel that have not channel-crossing structures. In dominant discharge, according to the results that analyzed relationship between $h/d_{50}$ and $V/u_*$ to calculate flow resistance by bed materials, Julian's formula showed to appropriate in channel where is relatively close to natural river and is predominantly consisted of gravel, cobble, boulder and rock in mountain, and it was confirmed that the image processing methodology will be easily applied to the analysis of bed materials distribution in future.