• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 B
• /
• pp.1231-1233
• /
• 1996

This paper presents an estimation of relative distance and angle from a mobile robot to an object. From the number of pulses required to make the mobile robot move to the feature point, we find the relative distance and angle between the mobile robot and the object. The proposed method shows a practical way of measuring the relative distance and angle between the mobile robot and an object without setting up real world coordinate system.

• 품질경영학회지
• /
• 제15권2호
• /
• pp.74-81
• /
• 1987

The purpose of this paper is to find out the relative priority among the queueing products for next operation. Critical ratio scheduling is a technique for use in production scheduling to establish and maintain relative priority among the jobs. The relative priority is based on a ratio of when the completed job is required and how much time is required to complete it. A numerical example of "D" company is solved. Jobs are classified into 3 categories; the behind scheduling jobs, the on time jobs and the ahead scheduling jobs.

• Korean Journal of Mathematics
• /
• 제27권1호
• /
• pp.17-51
• /
• 2019

In the paper we establish some new results depending on the comparative growth properties of composite entire and meromorphic functions using relative $_pL^*$-order, relative $_pL^*$-lower order and differential monomials, differential polynomials generated by one of the factors.

• Korean Journal of Mathematics
• /
• 제29권2호
• /
• pp.239-252
• /
• 2021

The prime target of this paper is to compare some relative (k, n) Nevanlinna defects with relative (k, n) Valiron defects from the view point of integrated moduli of logarithmic derivative of entire and meromorphic functions where k and n are any two non-negative integers.

• 한국수학교육학회지시리즈B:순수및응용수학
• /
• 제30권2호
• /
• pp.139-154
• /
• 2023

In this paper we wish to prove some results relating to the growth rates of composite entire and meromorphic functions with their corresponding left and right factors on the basis of their generalized relative order (α, β) and generalized relative lower order (α, β), where α and β are continuous non-negative functions defined on (-∞, +∞).

• 대한핵의학회지
• /
• 제25권2호
• /
• pp.227-236
• /
• 1991

Background: The evaluation of individual renal function is important to diagnosis and follow-up of various diseases. Ureteral catheterization of each kidney has been widely used for this purpose, but this method had some technical difficulty, frequent complications and much restriction in reapplication. Therefore we tried to applicate radiopharmaceuticals for the evaluation of individual renal function. Methods: We measured 2 hour, 4 hour and 24 hour relative renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate of $^{99m}Tc-DTPA$ with 59 patients with various renal diseases to determine their usefulness for assessment of individual renal function and to compare correlations between every renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate. Results: The correlations between 2 hour-, 4 hour- and 24 hour- relative renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate of $^{99m}Tc-DTPA$ were R=0.9190 (p < 0.001), R: 0.9229 (p<0.001) and R=0.9917 (p<0.001). In acute obstructive uropathy, the correlations at 2 hour and 4 houre were poor as R=0.1812 (p<0.05) and R=0.4923 (p < 0.05), but the correlation at 24 hour was good as R=0.9942 (p<0.001). Conclusions: We concluded that relative renal uptake at 2 hour and 4 hour had good correlation with relative DTPA uptake ratio in the cases without chronic renal failure and obstructive uropathy. Delayed image with 24 hour relative renal uptake $^{99m}Tc-DTPA$ had the best correlation with relative glomerular filteration rate of $^{99m}Tc-DTPA$ and that might be useful in evaluation of chronic renal disease in which showed increased beckground activity or acute obstructive uropathy.

• 수산해양기술연구
• /
• 제35권1호
• /
• pp.25-34
• /
• 1999

The Steering and Sailing Rules of International Regulation for Preventing Collisions at Sea now in use direct actions to avoid collision when two power-driven vessels are meeting on reciprocal or nearly reciprocal courses so as to involve risk of collision. But these rules do not refer to the minimum relative distances and safety relative distances between two vessels when they should take such actions.In this paper the ship's collision avoiding actions being analyzed from a viewpoint of ship motions, the mathematical formulas to calculate such relative distances necessary for taking actions to avoid collision were worked out. The values of maneuvering indices being figured out through experiments of 20 actual ships of small, medium, large and mammoth size and applied to calculating formulas, the minimum relative distances and safety relative distances were calculated. The main results were as follows. 1. It was confirmed that the criterion elements for collision avoiding actions in head-on situation of two vessels shall be the minimum relative distances and safety relative distances between them. 2. On the assumption that two vessels same in size and condition were approaching each other in head-on situation, the minimum relative distance of small vessel(GT : 160~650tons) was found to be about 4.7 times her own length, and those of medium (GT:2,300~4,500tons),large(GT:15,000~62,000tons) and mommoth (GT:91,000~194,000tons) vessels were found to be about 5.2 times, about 5.2 times and about 6.1 times their own lengths respectively. 3. On the assumption that two vessels same in size and condition were approaching each other in head-on situation, the safe relative distance of small vessel (GT : 160~650tons) was found to be about 6.8 times her own length, and those of medium (GT : 2,300~4,500tons), large (GT: 15,000~62,000tons) and mammoth (GT : 91,000~194,000tons) vessels were found to be about 9.0 times, about 6.3 times, and about 8.0 times their own lengths respectively. 4. It is considered to be helpful for the safety of ship handling that the sufficient safe relative distances for every vessels shall be more than about 12~14 times which are 2 times minimum relative distance, their own length on above assumption.

• 한국어류학회지
• /
• 제32권2호
• /
• pp.55-62
• /
• 2020

상대 무게 지수(Relative weight index, W_r)는 어류의 표준 무게와 실측 무게의 비율을 산출하는 지수로써 영양상태를 평가하는데 활용된다. 본 연구의 목적은 상대 무게 지수 활용을 위해 국내 담수어류 10종의 표준 무게 산출을 위한 길이-무게 상관관계(표준 LWRs)를 산출하는 것과, 상대 무게 지수 산출 결과에 대한 빈도 분포를 분석하는 것이다. 총 141개 조사 지점에서 798회 어류 채집을 통해 확보한 어류의 길이-무게 데이터를 활용하여 LWRs를 산출하였다. LWRs는 매개변수 a와 b값을 95% 신뢰한계(confidence limits)와 함께 제시하였으며, 모든 종에서 결정계수(r²)는 0.9 이상으로 산출되었고, b값은 Froese (2006)의 예상 범위에 포함되었다. 상대 무게 지수 산출 결과에 대한 빈도 분포 분석은 각 종별로 10~90 백분위수를 10 단위로 산출하여 제시하였으며, 이는 상대 무게 지수를 활용하여 어류의 영양상태를 정량적으로 평가하기 위한 기준으로 활용될 수 있을 것으로 판단된다.

• 한국환경보건학회지
• /
• 제41권6호
• /
• pp.412-424
• /
• 2015

Objectives: An ultra dry air environment of nearly ${\leq}2%$ RH is often required in lithium battery factories. The objective of this study is to evaluate the subjective eye, pulmonary, nose, and skin symptoms of workers exposed to ultra-low relative humidity and thionyl chloride. Methods: We recruited 274 workers using a self-reported questionnaire in March 2014. Those who worked in ultra-low relative humidity and with thionyl chloride were identified and their prevalence of symptoms was compared with that of other workers. We excluded white collar workers, researchers and other workers who were exposed to various hazard factors, and finally included 164 workers. Results: There were significant differences in the rate of self-reported eye and skin symptoms between exposure group_1 and exposure group_2. Exposure group_2 experienced more frequent eye, and skin symptoms. Multinomial logistic regression analysis for experience of dry eye symptoms and skin symptoms in exposure group_2 showed that dry eye symptoms (odds ratio [OR], 6.33, 95% confidence interval [CI], 2.19-18.24, p<0.001), and itchiness (OR, 6.45, 95% CI, 1.94-21.43, p<0.01) were the significant variables. The complaints of workers experiencing ultra-low relative humidity and thionyl chloride were high compared with other workers. Conclusion: These findings suggest that exposure to ultra-low relative humidity and thionyl chloride may be associated with more frequent eye and skin symptoms than exposure to ultra-low relative humidity alone. The current precautions to protect workers from the adverse effects of ultra-low relative humidity and thionyl chloride appear to be insufficient, indicating that additional management plans to reduce symptoms should be considered.

• 노동경제논집
• /
• 제40권2호
• /
• pp.1-29
• /
• 2017

본 연구는 동료(peer)에 대비한 학생의 상대적인 학업성취가 진로 결정에 어떠한 영향을 주는지를 살펴본다. 구체적으로 학교 내에서 학생들의 상대적인 수학 순위가 이과 선택에 미치는 영향을 분석하였다. 분석을 위해 서울시 소재 학생들의 패널데이터를 이용하였으며, 수학 성적을 통제하더라도 상대 순위가 낮은 경우 이과에 진학할 확률이 11%포인트 이상 감소함을 확인하였다. 높은 상대 순위는 여학생에게 추가적인 양의 이과 진학 효과를 나타내 상대 순위가 성별로 다르게 작용함을 보였다. 분석 결과에 따르면 상대 순위효과 중 약 12%만이 자신감과 같은 주관적 평가에 의해 설명되며, 이로 미루어보아 내신 성적을 통한 경로가 더 지배적일 것으로 추측할 수 있다.