• Progress in Superconductivity
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• v.4 no.2
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• pp.114-120
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• 2003

We employed a method eliminating a temporally partial principal component (PC) of multichannel-recorded neuromagnetic fields for excluding spatially correlated noises from event-evoked signals. The noises in magnetoencephalography (MEG) are considered to be mainly spontaneous neuromagnetic fields which are spatially correlated. In conventional MEG experiments, the amplitude of the spontaneous neuromagnetic field is much lager than that of the evoked signal and the synchronized characteristics of the correlated rhythmic noise makes it possible for us to extract the correlation noises from the evoked signal by means of the general PC analysis. However, the whole-time PC of the fields still contains a little projection component of the evoked signal and the elimination of the PC results in the distortion of the evoked signal. Especially, the distortion will not be negligible when the amplitude of the evoked signal is relatively large or when the evoked signals have a spatially-asymmetrical distribution which does not cancel out the corresponding elements of the covariance matrix. In the period of prestimulus, there are only the spontaneous fields and we can find the pure noise PC that is not including the evoked signal. Besides that, we propose a method, called the extended temporal decorrelation method (ETDM), to suppress the distortion of the noise PC from remanent evoked signal components. In this study, we applied the Partial Principal component elimination method (PPCE) and ETDM to simulated signals and the auditory evoked signals that had been obtained with our homemade 37-channel magnetometer-based SQUID system. We demonstrate here that PPCE and ETDM reduce the number of epochs required in averaging to about half of that required in conventional averaging.

• Journal of The Korean Association For Science Education
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• v.16 no.2
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• pp.190-199
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• 1996

The purpose of this study was twofold: (1) to design a system for constructing Likert attitude scales as supported by the sociopsychological and measurement literature, and (2) (using the design) to develop an affective component of "Attitudes toward Science" scale for high school students. The rationale for developing a new attitude scale is presented in the context of a review of existing attitude scales. As discussed in the literature review, many existing attitude scales are based on ill-defined theoretical constructs, and includes statements that do not appear to be assessing a single construct of attitude toward science. In addition, existing attitude scales do not distinguish between affective and behavioral and cognitive components of attitude toward science. Thus, this study was to carefully define the construct, subcomponents of attitude toward science, and develop an affective component of "Attitude toward Science" scale to reflect the construct and to distinguish between affective and behavioral and cognitive components of attitude toward science. The results of this study: (1) three-mains step for designing reliable and valid attitude scale were developed, and (2) 35 items(16 positive and 19 negative) for an affective component of "Attitudes toward Science" scale with the following characteristics were developed: (a) The internal consistency was estimated using Cronbach's coefficient ${\alpha}$, 0.9727. (b) The range of adjusted item-total correletion(${\gamma}$-value) were 0.58${\sim}$0.83. (c) The correlation coefficient ranged between 0.61 and 0.74 revealing a moderate relatedness between subcomponents. (d) The correlation coefficient for concurrent validity were 0.55 with TOSRA and 0.51 with SAl.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.6
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• pp.313-327
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• 2017

The purpose of this study is to predict the effects of macroscopic and integrative therapies by finding active ingredients, potential targets of Astragalus membranaceus (Am) and Cornus officinalis (Co) for diabetic nephropathy. We have constructed network pharmacology-based systematic and network methodology by system biology, chemical structure, chemogenomics. We found several active ingredients of Astragalus membranaceus (Am) and Cornus officinalis (Co) that were speculated to bind to specific receptors which had been known to have a role in the progression of diabetic nephropathy. Four components of Am and eleven components of Co could bind to iNOS; two ingredients of Am and six ingredients of Co could docking to cGB-PDE; one component of Am and nine components of Co could bind to ACE; three ingredients of Co with neprilysin; three components of Co with ET-1 receptor; four ingredients of Am and fourteen ingredients of Co with mineralocorticoid receptor; one component of Am and seven components of Co with interstitial collagenase; one ingredient of Am and ten ingredients of Co with membrane primary amine oxidase; one component of Am and four components of Co with JAK2; two ingredients of Am and one ingredient of Co with MAPK 12; one component of Am and five components of Co could docking to TGF-beta receptor type-1. From this work we could speculate that the possible mechanisms of Am and Co for diabetic nephropathy are anti-inflammatory, antioxidant and antihypertensive effects.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.4
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• pp.119-132
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• 2004

As geographic object is consisted of 3-dimensional, it must be appropriated use the 3-dimensional coordinate system to express for exact representation. To define 3-dimensional+temporal object model we extended 3-dimensional space and valid time from object model of OpenGIS consortium that is limited to 2-dimensional space. This methodology guarantees compatibility with other systems to construct with the open model. Also, it permitted administration for two kinds of object by considering both objects whose position and shape changes discretely over time and objects whose position changes continuously. 3-dimensional+temporal object model was implemented by 3-dimensional+temporal object component using OLE/COM techniques. The interfaces of the component defined based on 3-dimensional+temporal object model. To use this component, we implement the data consumer for 3-dimensional+temporal data.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.2
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• pp.165-179
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• 2005

Close collaboration among businesses is required in B2B EC environment. Furthermore, emergency requests or critical information among businesses should be processed in an immediate mode. Most current systems, however, due to firewalls for the systems' security and autonomy, can not handle these requirements appropriately, but handle them in an ad hoc manner In this paper a method of timely collaboration among businesses and an active functionality component to support it in B2B EC environment are proposed. Since the active functionality component supports high level ECA rule patterns and event-based immediate processing, system administrators and programmers can easily program and maintain the timely collaboration independently to the application logic. The proposed active functionality component uses HTTP protocol to be applied through firewalls and is designed using a commercial DBMS for practical purpose.

• Investigative Magnetic Resonance Imaging
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• v.23 no.3
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• pp.202-209
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• 2019

Purpose: To investigate the temperature-based differences of cortical bone ultrashort echo time MRI (UTE-MRI) biomarkers between body and room temperatures. Investigations of ex vivo UTE-MRI techniques were performed mostly at room temperature however, it is noted that the MRI properties of cortical bone may differ in vivo due to the higher temperature which exists as a condition in the live body. Materials and Methods: Cortical bone specimens from fourteen donors ($63{\pm}21$ years old, 6 females and 8 males) were scanned on a 3T clinical scanner at body and room temperatures to perform T1, $T2^*$, inversion recovery UTE (IR-UTE) $T2^*$ measurements, and two-pool magnetization transfer (MT) modeling. Results: Single-component $T2^*$, $IR-T2^*$, short and long component $T2^*s$ from bi-component analysis, and T1 showed significantly higher values while the noted macromolecular fraction (MMF) from MT modeling showed significantly lower values at body temperature, as compared with room temperature. However, it is noted that the short component fraction (Frac1) showed higher values at body temperature. Conclusion: This study highlights the need for careful consideration of the temperature effects on MRI measurements, before extending a conclusion from ex vivo studies on cortical bone specimens to clinical in vivo studies. It is noted that the increased relaxation times at higher temperature was most likely due to an increased molecular motion. The T1 increase for the studied human bone specimens was noted as being significantly higher than the previously reported values for bovine cortical bone. The prevailing discipline notes that the increased relaxation times of the bound water likely resulted in a lower signal loss during data acquisition, which led to the incidence of a higher Frac1 at body temperature.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.4
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• pp.143-148
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• 2019

We have successfully fabricated high aspect-ratio GaN-based nanowires on Si substrates using molecular beam epitaxy (MBE) system for high-efficiency hydrogen generation of photoelectrochemical water splitting. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) demonstrated that p-GaN:Mg and p-InGaN nanowires were grown vertically on the substrate with high density. Furthermore, it was also confirmed that the emission wavelength of p-InGaN nanowire can be adjusted from 552 nm to 590 nm. Such high-aspect ratio p-InGaN nanowire structure will be a solid foundation for the realization of ultrahigh-efficiency photoelectrochemical water splitting through sunlight.

• Journal of Navigation and Port Research
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• v.35 no.3
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• pp.187-195
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• 2011

A ship handling simulator is popular means of preventing marine accidents caused by human error. It can also be used to train navigators. A real-time 3D visualization system, a component of a ship handling simulator, is an important component, as realistic and intuitive image generation play an essential role in improving the effects of education using ship handling simulators. This paper discusses the design of a new real-time 3D visualization system based on an open source 3D graphics engine as well as its implementation. The developed real-time 3D visualization system satisfies the operational requirements derived in terms of visualization functionalities, reuse of legacy graphic data, and interoperability with other systems constituting a ship handling simulator. This system has an architecture in which new functionalities are easily added.

• Journal of Korea Multimedia Society
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• v.10 no.1
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• pp.26-35
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• 2007

We present a robust face tracking system from the sequence of video images based on effective detector and Kalman filter. To construct the effective face detector, we extract the face features using the five types of simple Haar-like features. Extracted features are reinterpreted using Principal Component Analysis (PCA), and interpreted principal components are used for Support Vector Machine (SVM) that classifies the faces and non-faces. We trace the moving face with Kalman filter, which uses the static information of the detected faces and the dynamic information of changes between previous and current frames. To make a real-time tracking system, we reduce processing time by adjusting the frequency of face detection. In this experiment, the proposed system showed an average tracking rate of 95.5% and processed at 15 frames per second. This means the system is robust enough to track faces in real-time.

• Journal of Ocean Engineering and Technology
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• v.26 no.4
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• pp.57-63
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• 2012

In this paper, a Bayesian classifier based on PCA (principle component analysis) is proposed to classify underwater transient signals using $16^{th}$ order LPC (linear predictive coding) coefficients as feature vector. The proposed classifier is composed of two steps. The mechanical signals were separated from biological signals in the first step, and then each type of the mechanical signal was recognized in the second step. Three biological transient signals and two mechanical signals were used to conduct experiments. The classification ratios for the feature vectors of biological signals and mechanical signals were 94.75% and 97.23%, respectively, when all 16 order LPC vector were used. In order to determine the effect of underwater noise on the classification performance, underwater ambient noise was added to the test signals and the classification ratio according to SNR (signal-to-noise ratio) was compared by changing dimension of feature vector using PCA. The classification ratios of the biological and mechanical signals under ocean ambient noise at 10dB SNR, were 0.51% and 100% respectively. However, the ratios were changed to 53.07% and 83.14% when the dimension of feature vector was converted to three by applying PCA. For correct, classification, it is required SNR over 10 dB for three dimension feature vector and over 30dB SNR for seven dimension feature vector under ocean ambient noise environment.