• 한국환경복원기술학회지
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• 제19권4호
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• pp.19-28
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• 2016

The objectives of this study were to establish the slope criteria and analyze the forest land restoration plan in North Korea. Reviewing the literature of the countries, the relationships among the climate, erosion controls, and slope criteria with forest restoration programmes, implemented were analyzed. Comparison of forest land management policies was conducted between South and North Korea. The soil erosion controls using biological barriers were at $15{\sim}20^{\circ}$slopes in arid climate regions and $25{\sim}30^{\circ}$ in humid climate regions. In the case of South Korea, an afforestation policy from the "Act on Clearance Project of Slash-and Burn Agriculture" of 1966 was enforced on mountains with slope greater than $20^{\circ}$, however, at present, the "Marginal Cropping Land Policy" recommends cropping lands with slope bigger than $8.5^{\circ}$ to forest land. In 1961, in "Land Reclamation of One Million Hectare", North Korea reclaimed additional cropping lands with slope bigger than $8.5^{\circ}$, and currently, the "Act on Forestry" states to enforce reforestation with slope bigger than $20^{\circ}$. This study recommends that South Korea aids for forest land restoration in North Korea based on the different stages of their development on reconciliation and cooperation between South and North Korea.

• 대한구순구개열학회지
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• 제7권2호
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• pp.123-132
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• 2004

The purpose of this study was to obtain normative nasalance scores for adult subjects speaking the Korean language. Additional objectives of the study were to determine if speaker sex played a role in differences in nasalance score and there was significantly correlation of nasalance score with nasalance slope score. The subjects include 75 healthy young Korean adults with normal oral and velopharyngeal resource and function. They had no history of speech problem, were judged as having normal speech and resonance at the time of testing, and had no upper respiratory tract infections or allergies at the time of testing. The Nasometer II 6400 was used to obtain nasalance scores and nasalance slope scores for /a/, /i/, /e/, /o/, /u/, /ja/, /je/, /wi/, /p'ap'i/ and /sasi/. The data of nasalance and nasalance slope were analyzed statistically. The mean nasalance score of the female was significantly higher than that of male at /a/, /i/, /wi/, /p'ap'i/ and /sasi/(p <0.10). The mean nasalance score of /i/ was highest and that of /o/ was the lowest. In this study, we could not and the relationship of the nasalance score and the closing slope score. However, there was negative correlation between the mean nasalance score and the opening slope score at ie/ and /;ai, positive to /sasi/. These normative nasalance scores for normal young adults speaking the Korean language provide important reference information for Korean cleft palate teams. In the future study of velopharygneal activity with the Nasometer, the opening slope score will be able to be the important parameter.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1991년도 추계학술발표회 논문집 지반공학에서의 컴퓨터 활용 COMPUTER UTILIZATION IN GEOTECHNICAL ENGINEERING
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• pp.47-61
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• 1991

建設完了 直前에 破壞된 英國의 CARSINGTON DAM에 대하여 주어진 設計强度定數 및 實驗結果値를 適用하여 'PC-SLOPE'과 'PCSTABL5M'에 의해서 斜面을 解析하고 그 結果를 本稿에 收錄하였다. 解析過程은 設計斷面의 解析과 破壞後의 調査過程에서 나타난 特性을 考慮한 解析으로 나누었다. 解析結果 設計斷面은 주어진 間隙水壓係數를 適用할 때 安全係數가 1.2以上으로 適切한 設計가 이루어진 것으로 나타났으며, 暴雨에 의한 急　한 地下水位上界과 黃色粘土層의 影響으로 設計時 適用한 間隙水壓以上의 過剩間隙水壓이 作用하게 되어 DAM上流 斜面의 破壞는 不可避하였던 것으로 分析된다.

• Wind and Structures
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• 제31권4호
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• pp.351-362
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• 2020

In this study, the impact of roof slope on the flow characteristics over low-sloped gable roofs was investigated using steady computational fluid dynamics (CFD) simulations based on a k-ω SST turbulence model. A measurement database of the flow field over a scaled model of 15° was created using particle image velocimetry (PIV). Sensitivity analyses for the grid resolutions and turbulence models were performed. Among the three common Reynolds-averaged Navier-Stokes equations (RANS) models, the k-ω SST model exhibited a better performance, followed by the RNG model and then the realizable k-ε model. Next, the flow properties over the differently sloped (0° to 25°) building models were determined. It was found that the effect of roof slope on the flow characteristics was identified by changing the position and size of the separation bubbles, 15° was found to be approximately the sensitive slope at which the distribution of the separation bubbles changed significantly. Additionally, it is suggested additional attention focused on the distributions of the negative pressure on the windward surfaces (especially 5° and 10° roofs) and the possible snow redistribution on the leeward surfaces.

• 대한원격탐사학회지
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• 제27권3호
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• pp.369-377
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• 2011

Since well-calibrated satellite data is critical for their applications, calibration and validation of COMS science data was one of the key activities during the IOT. COMS MI radiometric calibration process was divided into two phases according to the out-gassing of the sensor: calibrations of the visible (VI) and infrared (IR) channels. Different from the VIS calibration, the calibration steps for the IR channels followed additional processes to secure their radiometric performances. Primary calibration steps of the IR were scan mirror emissivity correction, midnight effect compensation, slope averaging and 1/f noise compensation after a nominal calibration. First, the scan mirror emissivity correction was conducted to compensate the variability of the scan mirror emissivity driven by the coating material on the scan mirror. Second, the midnight effect correction was performed to remove unreasonable high spikes of the slope values caused by the excessive radiative sources during the local midnight. After these steps, the residual (difference between the previous slope and the given slope) was filtered by a smoothing routine to eliminate the remnant random noises. The 1/f noise compensation was also carried out to filter out the lower frequency noises caused from the electronics in the Imager. With through calibration processes during the entire IOT period, the calibrated IR data showed excellent performances.

• 한국측량학회지
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• 제19권2호
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• pp.183-188
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• 2001

사면 슬라이딩에 따른 추가 세부 공사 계획의 수행에 중요하게 사용되는 데이터는 지형도이다. 이는 사면 슬라이딩이 발생한 지역의 토공량 산정과 공사비 산출, 그리고 안전성 검토에 사용되는 기본도인 것이다. 따라서, 본 연구에서는 사면 슬라이딩이 발생한 위험사면에 대해 소프트카피 사진측량을 적용하여 3차원 지형데이터를 획득하고, 이를 기존 TM 좌표의 지형도와 동일한 좌표 체계로 변환하는 방안을 구축하였다. 300 m 전방에서 촬영한 영상을 분석하여 1m등고선을 생성하는데 발생되는 문제점을 해결하여 도로 확장 공사의 터널 진입구간 계획에 중요한 데이터로 사용할 수 있었으므로, 토목 분야의 다양한 위험 지역의 측정에 그 효용성이 높은 것으로 사료된다.

• 한국의류학회지
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• 제24권1호
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• pp.105-115
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• 2000

This study was intended to find body pattern of middle aged women and make new experimental basic pattern for upper-half of the body for them. This experimental pattern on the idea of body pattern analysis was prepared. For experimental pattern, the prototype basic model was chosen with the best qualified D model from the four meaningful existing patterns. After several steps of correction experimental pattern was made. Comparing with basic D model, the new experimental pattern composed of additional bust girth by 1cm, wider back waist by 0.5cm than front waist and additional armhole by 0.5cm keeping the same size for back and front widths. Making a shoulder line up by 3cm the armhole became deeper accordingly and the room for girth has been transferred to length. Front neck girth became deeper downward but back neck girth risen a little bit. Side line of the bodice formed with inward slope taking from the waist line by 2cm. Instead of dart, modified side line slope was more practical by its function and appearance. Abdominal girth which is lower than waist girth by 8.5cm kept in same size with bust girth. Then abdominal girth became more comfortable. New experimental pattern with changes has been examined in function and appearance. In conclusion, the new experimental basic pattern for the middle-aged women has been proved more practical for both in bodice and sleeve than other existing ones in terms of function and appearance.

• 한국해양공학회지
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• 제30권5호
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• pp.341-348
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• 2016

The fatigue damage caused by wide band loadings has generally been predicted using fatigue damage models in the frequency domain rather than a rain-flow counting method in the time domain because of its computation cost. This study showed that these fatigue damage models can be simplified in the form of normalized fatigue damage as a function of the S-N curve slope and bandwidth parameters. Based on numerical simulations of various wide band spectra, it was found that fatigue damage models in the form of normalized fatigue damage with one S-N curve slope and two bandwidth parameters( α₁ , α₂ ) provided less reasonable fatigue damage. Therefore, an additional bandwidth parameter needs to be considered based on a sensitivity study using various neural networks, which proved that α_1-5 would be the dominant factor of a fatigue damage model as an additional bandwidth parameter.

• 한국산학기술학회논문지
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• 제19권4호
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• pp.123-131
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• 2018

본 연구는 ${\bigcirc}{\bigcirc}$ 고속국도 공사 중 발생된 이암 절토 사면의 붕괴 요인 분석 및 대책방안을 제시하였다. 기반암인 이암에 대해 실내시험을 수행하고, 국제 기준에 의거해 공학적인 특성을 규명하였다. 그리고 설계 시 수행되었던 사면안정해석을 재검토 하였다. 또한, Swelling-Slaking 현상으로 인해 기반암인 이암의 강도열화특성을 고려한 안정해석을 추가적으로 수행하였다. 기반암인 이암에 대해 Swelling-Slaking Test 결과, 풍화내구성은 낮음-보통으로 나타났으며, 팽창변형률은 매우 낮음으로 나타났다. 설계 안정해석 검토 결과, 이암의 공학적 특성을 고려하지 않고, 한계평형해석을 이용해 실제와 상이한 결과가 나타났다. 강도열화특성을 고려한 추가안정해석 결과, 사면의 붕괴지점과 안정해석의 최대전단변형률 발생지점이 동일하게 나타났으며, 건기시 우기시 모두 기준 안전율을 만족하지 못하였다. 붕괴 사면의 대책방안으로는 사면경사완화공법이 가장 적절하였다. 유한요소해석을 통해 완화 경사를 산정하였다. 완화 경사의 현장 적용성을 위해 시추공영상촬영과 비교한 결과, 미고결된 이암의 대부분이 제거되는 것으로 나타나 미고결된 이암으로 인한 추가적인 붕괴 위험성은 현격히 저하되는 것으로 나타났다.

• 전력전자학회논문지
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• 제17권5호
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• pp.401-408
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• 2012

A simple on-line elimination strategy of the dead time and inverter nonlinearity using the current slope information is presented for a PWM inverter-fed IPMSM (Interior Permanent Magnet Synchronous Motor) drive. In a PWM inverter-fed IPMSM drive, a dead time is inserted to prevent a breakdown of switching device. This distorts the inverter output voltage, resulting in a current distortion and torque ripple. In addition to the dead time, inverter nonlinearity exists in switching devices of the PWM inverter, which is generally dependent on operating conditions such as the temperature, DC link voltage, and current. The proposed scheme is based on the fact that the d-axis current ripple is mainly caused by the dead time and inverter nonlinearity. To eliminate such an influence, the current slope information is determined. The obtained current slope information is processed by the PI controller to estimate the disturbance caused by the dead time and inverter nonlinearity. The overall system is implemented using DSP TMS320F28335 and the validity of the proposed algorithm is verified through the simulation and experiments. Without requiring any additional hardware, the proposed scheme can effectively eliminate the dead time and inverter nonlinearity even in the presence of the parameter uncertainty.