• Communications for Statistical Applications and Methods
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• 제31권3호
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• pp.349-363
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• 2024

Compositional data refers to data where the sum of the values of the components is a constant, hence the sample space is defined as a simplex making it impossible to apply statistical methods developed in the usual Euclidean vector space. A natural approach to overcome this restriction is to consider an appropriate transformation which moves the sample space onto the Euclidean space, and log-ratio typed transformations, such as the additive log-ratio (ALR), the centered log-ratio (CLR) and the isometric log-ratio (ILR) transformations, have been mostly conducted. However, in scenarios with sparsity, where certain components take on exact zero values, these log-ratio type transformations may not be effective. In this work, we mainly suggest an alternative transformation, that is the square-root transformation which moves the original sample space onto the directional space. We compare the square-root transformation with the log-ratio typed transformation by the simulation study and the real data example. In the real data example, we applied both types of transformations to the USG% data obtained from NBA, and used a density based clustering method, DBSCAN (density-based spatial clustering of applications with noise), to show the result.

• 대한토목학회논문집
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• 제10권3호
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• pp.1-6
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• 1990

다지점지진하중(多支點地震荷重)을 받는 사경문(四徑問) 연속철도교양(連續鐵道橋梁)의 동적거동(動的擧動)을 응답(應答)스펙트럼법(法)에 의하여 조사(調査)하였다. 소진복(小振福)의 진동(振動)과 재료(材料)의 선형(線形)-탄성거동(彈性擧動)을 가정(假定)하였으며, 지반(地盤)-구조물(構造物) 상호작용(相互作用) 효과(效果)는 무시(無視)하였고, 교량(橋梁)의 횡방향(橫方向) 등답(應答)만을 고려(考慮)하였다. 응답(應答)스펙트럼해석(解析)의 결과(結果)는 시간이력해석결과(時間履歷解析結果)와 비교(比較)되었으며 모우드 최대치(最大値)와 지지점운동(支持點運動)의 중량(重量)은 여러가지 조합법칙(組合法則) 즉(卽), Square-Root-Of-Sum-Squares, Double Sum, 그리고 P-Norm Rule을 적용(適用)하였다.

• 한국안전학회지
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• 제29권6호
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• pp.166-171
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• 2014

Nuclear power plants are equipped with the reactor trip system (RTS) and the engineered safety features actuation system (ESFAS) to improve safety on the normal operation. In the event of the design basis accident (DBA), a various of post accident monitor(PAM)systems support to provide important details (e.g. Containment pressure, temperature and pressure of reactor cooling system and core exit temperature) to determine action of main control room (MCR). Operator should be immediately activated for the accident mitigation with the information. Especially, core exit temperature is a critical parameter because the operating mode converts from normal mode to emergency mode when the temperature of core exit reaches $649^{\circ}C$. In this study, uncertainty which was caused by exterior environment, characteristic of thermocouple/connector and accuracy of calibrator/indicator was evaluated in accordance with ANSI-ISA 67.04. The square root of the sum of square (SRSS) methodology for combining uncertainty terms that are random and independent was used in the synthesis. Every uncertainty that may exist in the hardware which is used to measure the core exit temperature was conservatively applied and the associative relation between the elements of uncertainty was considered simultaneously. As a result of uncertainty evaluation, the channel statistical allowance (CSA) of single channel of core exit temperature was +1.042%Span. The range of uncertainty, -0.35%Span ($-4.05^{\circ}C$) ~ +2.08%Span($24.25^{\circ}C$), was obtained as the operating criteria of core exit temperature.

• 자원ㆍ환경경제연구
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• 제9권3호
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• pp.461-487
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• 2000

Kang et al. (1999) computed a composite environmental index in Korea by practicing the survey for environmental experts. They used the weighted sum form among feasible aggregation forms. In this study, we carry out the survey for both experts and non-experts to see the degree of differences of the weights for nine types of environmental problems between two groups. In addition, we apply different aggregation forms such as linear sum, weighted sum, root-sum-power, root-mean-square forms and compare these four outcomes. We found no significant discrepancy in the trends of composite indices. In case we rely on the weights provided by the experts, the composite index, on average, has been increased annually by about 7.2% over the 1986~1997 period, which informs us that overall environmental quality in 1997 has been worse than in 1986 by about 1.8 times.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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• pp.258-261
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• 2007

본 논문은 항공엔진이 전 운용범위 및 운용조건에서 성능요구조건을 만족할 수 있도록 설계 및 운용 한계를 설정하는 MEPS 기법에 관한 내용이다. 대기습도, 엔진품질, 추력설정부정확 및 성능감쇠 등의 영향이 산술적으로 반영되는 Direct Adder와 Root Sum Square로 반영되는 Random Adder에 대해 기술하였다. 본 기법을 4,000Ib급의 상용 터보팬 엔진개발에 적용하여, 각 Adder의 영향성을 분석하여 엔진설계 및 운용한계 설정을 위한 MEPS를 구축하였다.

• International Journal of Safety
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• 제7권1호
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• pp.26-29
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• 2008

The purpose of this study is the measurement of whole-body vibration for different road surfaces. Experimental measurements were taken on asphalt, cement, and off-road surfaces as defined by ISO 2631-1. Each experiment was conducted under the same set of conditions (measurement duration, times, speed, vehicle type). Measurement duration was 10 minutes and 3 separate measurements were taken on each road surface. Vehicle speed was 60km/h. In accordance with ISO 2631-1, an acceleration sensor is set up between the driver's seat and the human body. For evaluation, RMS(root-mean-square) values were taken as suggested by ISO 2631-1. The results suggest "health guidance caution zones", and the evaluation was based on obtaining the vector sum with "health guidance caution zones".

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.361-365
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• 2006

In order to predict method of blasting vibration in ground and it's resident located around blasting field in urban area, blasting vibration characteristics were measured the vibration velocity(cm/sec), vibration acceleration($cm/sec^2$), vibration acceleration level(dB) and vibration level(dB(V)). The charged powder were used to 1.25kg and measuring sites were 25 points front 4m to 90m at the ground. The correlation of vibration velocity, vibration acceleration, vibration acceleration level and vibration level by square root scaled distance and cube root scaled distance were investigated. The correlation of PPV(peak particle velocity) velocity by SRSD(square root scaled distance) and CRSD(cube root scaled distance) was 0.85 and 0.86 and the correlation of PVS(peak vector sum) velocity by SRSD and CRSD was 0.82. Also vibration acceleration, vibration acceleration level and vibration level by SRSD and CRSD was 0.61, 0.62 and 0.82, respectively. As results, the vibration velocity and vibration level(dB(V)) was showed good correlation, but the vibration acceleration and vibration acceleration level was not showed good correlation.

• 대한수학회지
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• 제57권4호
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• pp.1019-1030
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• 2020

Efficient computation of r-th root in 𝔽_q has many applications in computational number theory and many other related areas. We present a new r-th root formula which generalizes Müller's result on square root, and which provides a possible improvement of the Cipolla-Lehmer type algorithms for general case. More precisely, for given r-th power c ∈ 𝔽_q, we show that there exists α ∈ 𝔽_q^r such that $$Tr{\left(\begin{array}{cccc}{{\alpha}^{{\frac{({\sum}_{i=0}^{r-1}\;q^i)-r}{r^2}}}\atop{\text{ }}}\end{array}\right)}^r=c,$$ where $Tr({\alpha})={\alpha}+{\alpha}^q+{\alpha}^{q^2}+{\cdots}+{\alpha}^{q^{r-1}}$ and α is a root of certain irreducible polynomial of degree r over 𝔽_q.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.233-240
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• 1999

A general procedure is presented here to develope seismic design and analysis method for cable-supported bridges like suspension bridges subjected to ground motion. For representing a numerical model of suspension bridges. a new approach which satisfy design conditions for the initial equilibrium state of suspension bridges. without any nonlinear iterations. is proposed. The dynamic behavior of that model is verified by free vibration analysis. This study uses the response spectrum analysis to determine the Peak response of a suspension bridge to earthquake-induced ground motion. The SRSS(Square Root of Sum of Square). modal combination rule, is adopted for each direction, longitudinal and transverse. To illustrate the potential applicability for the seismic design of suspension bridges, a numerical example is presented in which the dynamic response of the Nam-hae suspension bridge subjected to earthquake

• 상하수도학회지
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• 제18권3호
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• pp.351-356
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• 2004

Selecting appropriate G values in flocculator operation is important to produce high quality filter effluent in water treatment plants. However, misunderstanding and misleading of G calculation for the case of having power sources more than one or many paddles with one power source in a flocculation basin sometimes have led to low performance in flocculation. Theoretical analysis confirmed that the total G value in one flocculation unit having power sources more than one or with many paddles is the root-square of the sum of square of individual G value. This analysis also can give a simple calculation method of G value for designers and operators in fields.