• Journal of Biosystems Engineering
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• 제25권5호
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• pp.351-358
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• 2000

This study was conducted to develop a speed control system of a DC motor which drove a barley seeder mounted on a combine harvester. Barley seeder mounted on a combine has been known to reduce labor and cost of barley cultivation. However, development of the seeder has been unsuccessful because the combine, a dedicated rice and barley harvester has not enough space and proper power take-off for barley seeder. To develop a barley seeder, small powered motor speed controller was required. A proximity sensor for detecting working speed of the combine and a programmable one board microprocessor was used to develope a control system. Motor parameters and motor constant, relationship between seeding rate, motor speed, groove volumes of a tested roller, torque were measured. The proximity sensor sent a frequency signal to the microprocessor. In laboratory experiments, the excitation voltage of the motor was shown not to be proportional to the size of pulse width (duty ratio). A table transforming frequency signal, that represented for working speed to proper pulse width was developed from seeding rate experiments. However, seeding rate at low frequency signal was not proportional to the working speed. Seeding rate control proportional to the frequency signal was achieved by shifting of the frequency signal.

• 한국환경과학회지
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• 제6권6호
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• pp.605-612
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• 1997

This study is to evaluate the overall NPP(Net Primary Productions distribution in the Korean Peninsula from the satellite data(NOAA/AVHRR). This has been done using the linear relationship between the natural vegetation condition and the NPP. The NPP of natural vegetation increases proportional to the annual net radiation(Rn), where radiative dorless Index(RDI) is a proportional constant connecting Rn to NPP. Normalized Difference Vegetation Index(NDVI) Is used for monitoring vegetation change, and INDVI (Integrated NDVI) for annual analysis. The INDVI has a close relation to .Rn and NPP. which can be used effectively for estimating NPP distribution of where the meteorological data Is unavailable such as North Korea. The NPP distribution of the Korean Peninsula was estimated based on the model.

• International Journal of Precision Engineering and Manufacturing
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• 제8권4호
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• pp.45-49
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• 2007

When drilling using electrical-discharge machining (EDM), severe electrode wear makes in-process measurements of the depth of the drilled hole and the volume of material removed impossible. To estimate the volume of material removed a reliable real-time discharge pulse counting method is proposed by assuming that the volume removed in EDM is proportional to the number of discharge pulses from an iso-energy pulse generator. The geometry of machined holes, including depths and cross-sectional profiles, is estimated using geometric analysis. A proportional relationship between the volume of material removed and the number of discharge pulses was developed and verified by experiments.

• 대한치과교정학회지
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• 제16권2호
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• pp.81-97
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• 1986

The purpose of this study was to investigate the factors which cause the differences in the percentage of anterior overbite in spite of normal molar relationship in terms of skeletal, dental and dentoalveolar relations. The models and cephalograms taken from 154 subjects, 89 of shallow overbite and 65 of deep overbite ranging from 18 to 29 years of age were studied and analyzed statistically. The results were as follows. 1. In determining the percentage of anterior overbite, the significant differences were higher in the dental and dentoalveolar factors than in the skeletal factors and were higher in the proportional and angular measurements than in linear measurements. 2. The factor which had the greatest influence on the percentage of anterior overbite was the proportional parts of the dental and dentoalveolar heights. 3. The most influencing factor which determined the percentage of anterior overbite was the SN-MP angle among the skeletal factors.

• 한국주조공학회지
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• 제37권4호
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• pp.108-114
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• 2017

In this study, we investigated the effect of the Si content on the secondary dendrite arm spacing (SDAS) of hypoeutectic Al-Si binary alloys in the range of 4~10 wt% Si. Cooling curves were measured during the solidification of the alloy cast in a step-wise mold. We compared two kinds of solidification time: the first is the total solidification time for both dendritic and eutectic growth, and the second is the solidification time for only dendritic growth. The proportional constant in the relationship between SDAS and cooling rate was estimated, as this constant represents the stability of the cast microstructure. The proportional constant decreased with the Si contents from 4 wt% to 8 wt%, and it remains relatively uniform with up to 10 wt% of Si.

• Journal of Power Electronics
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• 제16권3호
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• pp.1004-1011
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• 2016

The inaccurate model parameters in the predictive current control of surface-mounted permanent magnet synchronous motor (SMPMSM) affect the current dynamic response and steady-state error. This paper presents a model parameter correction algorithm based on the relationship between the errors of model parameters and the static errors of dq-axis current. In this correction algorithm, the errors of inductance and flux are corrected in two steps. Resistance is ignored. First, the proportional relations between inductance and d-axis static current errors are utilized to correct the error of model inductance. Second, the flux is corrected by utilizing the proportional relations between flux and q-axis static current errors under the condition that inductance is corrected. An experimental study with a 100 W SMPMSM is performed to validate the proposed algorithm.

• 한국국방경영분석학회지
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• 제26권1호
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• pp.125-144
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• 2000

Occasionally, there are combat situations which one or both forces can´t terminate the combat using selected combat termination rule according to given relationship between ratio of attrition rate coefficient and threshold values. In this study, we classify the situations that one or both forces can´t terminate the combat with selected combat termination rule into four conditions. Condition${\circled1}$ is the situation which both Blue and Red can terminate the combat using all selected combat termination rules. condition${\circled2}$ and condition${\circled3}$ are those which neither Blue or Red can terminate the combat using selected proportional decision rule, and condition${\circled4}$ is that which both Blue and Red can´t terminate the combat using selected proportional decision rule. We analyze the effect of combat termination rules on parity number, final combat power, and combat durations for each conditions. Also, we propose the method to apply the analyzed effect of combat termination rules to combat analysis.

• 콘크리트학회논문집
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• 제13권6호
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• pp.553-560
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• 2001

철근콘크리트 휨부재의 비탄성해석 및 설계를 위해서는 연성능력의 평가가 필요하며, 이를 위해서는 모멘트-곡률 관계가 정의되어야 한다. 따라서, 본 연구에서는 모멘트 곡률관계를 가정하여 철근콘크리트 휨부재의 연성능력을 해석적 방법으로 구하고, 실험결과와 비교한 결과, 실험값과 해석값은 거의 일치하였으므로 가정한 모멘트-곡률관계는 적합한 것으로 판명 되었다. 또한, 연성률은 곡률연성, 회전연성, 변위연성을 비교하였으며, 철근콘크리트 휨부재의 연성능력에 주로 영향을 미치는 요소는 인장철근, 압축철근 및 휨보강근으로 보고, 실험값과 해석값을 다양하게 분석한 결과 ($\rho$$_{s}$ ＋ $\rho$')/$\rho$의 항으로 연성능력을 나타냄이 적절한 것으로 나타났다.

• 패션비즈니스
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• 제19권3호
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• pp.1-13
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• 2015

The purpose of this research is to analyze the morphological relationship between changes hair styles and changes in necklines and collars in 20th century fashion. After selecting the representative plate by each age for this study, the neckline, collar, and formative relevancy of hair style according to it have been analyzed by measuring the neckline, collar, and the width and height item of each hair style. The results of this study show- that the width changes of necklines and collars were mostly proportional in relation to each other, but the width changes of collars and hair styles were inversely proportional. While the amplitude of necklines and collars' width change was very broad, the amplitude of some hair style's height change was very broad. Regarding width, this result had similar results of the researcher's former research, the relation according to the width of necklines, collars and hair style from 16th century to 19th century. However, regarding height, this result was different from the preceding research in that the amplitude of hair style and collars' height change was very broad between 16th and 19th centuries, but the amplitude of neckline's height change is relatively small. This means various heights of necklines appeared in the 20th century, but more various heights of collars were shown between the 16th and 19th centuries. This research hopes to be helpful by predicting trends in fashion, and to be basic resources to understand the systemic relationship of these factors.

• 한국건축시공학회지
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• 제21권2호
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• pp.157-163
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• 2021

재해자수를 상시근로자수로 나눈 값이 재해율이다. 건설공사의 경우 공사실적과 노무비율을 기준으로 하여 상시근로자수를 추정하고 이를 이용하여 재해율을 산정하므로 재해율의 정확도가 낮아질 수 있다. 또한 현행 재해율 산정기준은 공사유형간의 특성을 반영하고 있지 않다. 본 연구는 공사종류별 특성을 고려한 재해율 보완방식을 제시하는 것으로 목적으로 진행하였으며, 지난 18년간의 공사실적 및 재해건수 통계자료를 바탕으로 상관분석과 선형회귀분석, 중회귀분석 등을 실시하여 공사유형과 재해유형간의 관계를 나타내는 회귀식을 도출하였다. 본 연구에서 제시한 수식은 기존의 건설공사 재해율의 단점을 보완하여 재해의 증감 및 예년대비 재해율의 높고낮음을 판단하는 보조지표로서의 활용이 가능할 것으로 기대된다.