• Journal of the Korean Data and Information Science Society
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• 제28권6호
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• pp.1565-1571
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• 2017

The standard logistic map is an iterative function, which forms a discrete-time dynamic system. The chaotic logistic map is a kind of ergodic map defined over the unit interval. In this paper we study the limiting behaviors on the several processes induced by the chaotic logistic map. We derive the law of large numbers for the process induced by the chaotic logistic map. We also derive the uniform law of large numbers for this process. When deriving the uniform law of large numbers, we study the role of bracketing of the indexed class of functions associated with the process. Then we apply the idea of DeHardt (1971) associated with the bracketing method to the process induced by the logistic map. We finally illustrate an application to Monte Carlo integration.

• 대한수학회논문집
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• 제9권3호
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• pp.701-710
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• 1994

Suppose ${X_n}$ is a Markov process taking values in some arbitrary space $(S, \varphi)$ with n-stemp transition probability $$ P^{(n)}(x, B) = Prob(X_n \in B$\mid$X_0 = x), x \in X, B \in \varphi.$$ We shall call a Markov process with transition probabilities $P{(n)}(x, B)$ $\phi$-irreducible for some non-trivial $\sigma$-finite measure $\phi$ on $\varphi$ if whenever $\phi(B) > 0$, $$ \sum^{\infty}_{n=1}{2^{-n}P^{(n)}}(x, B) > 0, for every x \in S.$$ A non-trivial $\sigma$-finite measure $\pi$ on $\varphi$ is called invariant for ${X_n}$ if $$ \int{P(x, B)\pi(dx) = \pi(B)}, B \in \varphi $$.

• 셀메드
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• 제3권1호
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• pp.1.1-1.7
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• 2013

The present review investigates the role of the cytoprotective enzyme heme oxygenase-1 (HO-1) in human diseases and explores strategies for its clinical use. In recent years, there has been a growing evidence, for the beneficial effects of some phytoconstituents via induction of HO-1 expression, contained in commonly used spices, fruits, and herbs, in preventing various pathologic conditions, including cancer, diabetes, and cardiovascular diseases. HO-1 catalyzes the rate-limiting step in heme catabolism to generate ferrous iron, carbon monoxide, and biliverdin. HO-1 is reported to play crucial roles in cellular protection, such as anti-inflammatory, anti-proliferative and anti-apoptotic effects. These evidences indicate that HO-1 may functions as a potential therapeutic target in various human diseases. The article highlights the current status of the development of the HO-1 modulation pathway using dietary phytoconstituents.

• 한국산학기술학회논문지
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• 제5권2호
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• pp.161-165
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• 2004

본 논문에서는 소속과 비소속의 정도를 나타내는 함수를 쌍으로 가진 intuitionistic 퍼지 원을 소개하고, 그들의 성질을 조사해 보았다. 또한, 퍼지 구의 개념을 2차원 영상에 적용하기 위하여 차원을 제한한 intuitionistic 퍼지 원이 극한 프로세스에 의해 퍼지 기하에 기여함을 볼 수 있다.

• Communications for Statistical Applications and Methods
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• 제27권2호
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• pp.163-175
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• 2020

We consider a wide class of general weakly-dependent processes, called ψ-weak dependence, which unify almost all weak dependence structures of interest found in statistics under natural conditions on process parameters, such as mixing, association, Bernoulli shifts, and Markovian sequences. For detecting the tail behavior of the weakly dependent processes, change point tests are developed by means of cumulative sum (CUSUM) statistics with the empirical distribution functions of sample extremes. The null limiting distribution is established as a Brownian bridge. Its proof is based on the ψ-weak dependence structure and the existence of the phantom distribution function of stationary weakly-dependent processes. A Monte-Carlo study is conducted to see the performance of sizes and powers of the CUSUM tests in GARCH(1, 1) models; in addition, real data applications are given with log-returns of financial data such as the Korean stock price index.

• 대한핵의학회지
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• 제37권1호
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• pp.53-62
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• 2003

After the development of two major techniques - SPECT (Single Photon Emission Computed Tomography) and PET (Positron Emission Tomography) to image the human subjects in a three-dimensional direction in the 1980s, many radiotracers have been used for functional neuroimaging. Still it would be very important study to develop selective radiotracers for functional neuroimaging. New radiotracers will help to expand the knowledge of neurotransmitter systems and of the genetic contribution to receptor or transporter availability. Neurotransmitter depletion-restoration studies, the distribution of brain functions and their modulation by neurotransmitter system aid in better understanding and limiting the side effects of drugs used as well as newly developed. In audition, these radiotracers will be thus very useful to gain a better understanding in biochemical and pharmacological interactions in living human. This review mentions the introduction of radioligands for the functional neuroimaging. Although significant progress has been achieved in the development of new PET and SPECT ligands for in vivo imaging of those receptors and transporters, there are continuous needs of new diagnostic radioligands.

• 전기학회논문지
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• 제68권4호
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• pp.593-597
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• 2019

We proposed a current Interruption type DC superconducting circuit breaker(I-DC SCB), a protection device that combines the current limiting technology of a superconductor with the cut-off technology of circuit breaker. Unlike existing protective devices, the current I-DC SCB is a device that combines two protection functions, notably improving failure probability and operational reliability. It is also applicable to all DC systems, such as HV, MV, and LVDC, due to the ease in capacity increase. The 100 kV I-DC SCB was designed after taking into account the actual power system conditions, followed by an analysis of the transient characteristics and the breaking range of the limiter. The results of the analysis showed that the I-DC SCB had a fault current limit of about 75% at the rated voltage, and completed the cut-off operation within about 20 ms.

• Journal of Korean Dental Science
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• 제10권2호
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• pp.45-52
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• 2017

Calcium has versatile roles in diverse physiological functions. Among these functions, intracellular $Ca^{2+}$ plays a key role during the secretion of salivary glands. In this review, we introduce the diverse cellular components involved in the saliva secretion and related dynamic intracellular $Ca^{2+}$ signals. Calcium acts as a critical second messenger for channel activation, protein translocation, and volume regulation, which are essential events for achieving the salivary secretion. In the secretory process, $Ca^{2+}$ activates $K^+$ and $Cl^-$ channels to transport water and electrolyte constituting whole saliva. We also focus on the $Ca^{2+}$ signals from intracellular stores with discussion about detailed molecular mechanism underlying the generation of characteristic $Ca^{2+}$ patterns. In particular, inositol triphosphate signal is a main trigger for inducing $Ca^{2+}$ signals required for the salivary gland functions. The biphasic response of inositol triphosphate receptor and $Ca^{2+}$ pumps generate a self-limiting pattern of $Ca^{2+}$ efflux, resulting in $Ca^{2+}$ oscillations. The regenerative $Ca^{2+}$ oscillations have been detected in salivary gland cells, but the exact mechanism and function of the signals need to be elucidated. In future, we expect that further investigations will be performed toward better understanding of the spatiotemporal role of $Ca^{2+}$ signals in regulating salivary secretion.

• Journal of Biosystems Engineering
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• 제2권1호
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• pp.33-48
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• 1977

Transporting agricultural products and the other material by the two-wheel-tractor (power-tiler)and trailer system may be one of its most widely used farming functions.The safety and hitching load for all the previaling performing conditions may be the general concern over the operation of the tiller-trailer system. In this study, a mathematical model to determine the static and dynamic forces excerting on the hitch point were developed . Based on the analysis of the model and the field measurements. the limiting hitching load and critical slope were analyzed. The results of the study are summarized as follows ; 1) The limit angle of slope land for the safety steering that two-wheel tractor-single axle trailer system was able to transport agricultural products was the direct angle (${\gamma}$) = 8 ; the cross angle$\beta$) 15 ; and it was decreased in accordance with the increase of carrying load ($W_4). 2) The critical velocity for safe operation in case of running on downward hill road was about 1.08m/sec. 3) The limiting carrying load for the safe steering was W$_4$=600kg. The degree of the safe steering for different braking methods was given in order as follows ; Simulataneous braking the tractor and trailer , braking the trailer only, and braking tractor only. 4) Among the three components of impact loads excerting on the hitch point, the component in the lateral direction ($P_{Vy}$) was near zero in spite of increase of hitching load ($W_4) , while the components in the other two mutually perpedicular directions ($P_{Vx}$ and ($P_{Vz}$) ) had larger values in horizontal plane than those in the slope lands. 5) Moment of forces on the lateral direction (M$y$) had the largest value among the three components of impact moment acting on the hitch point, however all the components were sharply increased in accordance with the increase of hitching loads ($W_4. Three components of the moment were the negative values.

• 한국비블리아학회지
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• 제31권3호
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• pp.191-211
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• 2020

본 연구는 시각장애인들의 독서보조기기를 이용한 정보접근에서 발생하는 한계와 문제점 등을 확인하고, 이를 기반으로 독서보조기기를 이용한 대체자료 이용 활성화 방안을 제안하는데 주된 목적을 두고 있다. 이를 위해 시각장애인 성인을 대상으로 설문조사를 수행하였으며, 설문 분석 결과를 통해 독서보조기기의 이용을 활성화하는데 있어서의 제한요인을 여섯 가지 측면으로 도출하였다. 도출한 제한요인을 중심으로 독서보조기기 이용 활성화를 위한 방안을 정책적, 운영적 측면으로 구분하여 제안하였다. 정책적 측면에서는 저가의 독서보조기기 개발, 독서보조기기 지원 정책에 대한 인지도 제고, 독서보조기기 적용성 향상을 위한 웹 표준 지침 준수 방안을 제안하였으며, 운영적 측면에서는 시각 이외에 청각 활용 기능의 보강, 독서보조기기 활용 관련 정보서비스 확충, 독서보조기기의 휴대성 강화 등을 제안하였다.