• 한국통신학회논문지
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• 제35권12A호
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• pp.1152-1159
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• 2010

무선 메쉬 네트워크는 무선 링크를 통해 백본 네트워크를 형성하여 사용자에게 인터넷 접근을 제공한다. WMN의 주요 이슈는 네트워크 용량이다. 이를 위해 IEEE 802.11 의 멀티 채널과 멀티 레이트를 활용할 수 있다. 채널은 채널 할당에 따라 노드 연결성 (node connectivity)과 채널 다양성 (channel diversity)을 결정한다. 또한, IEEE 802.11 멀티 레이트 네트워크에서는 RA (Rate Anomaly) 문제가 발생하는데, 이는 낮은 레이트 링크들이 높은 레이트 링크의 성능을 심각히 저하시키는 현상이다. 본 논문에서는 노드 연결성과 채널 다양성을 향상시키고 RA문제를 완화하는 레이트 분할 멀티 채널 (Rate Separating Multi-Channel, RSMC) 프로토콜을 제안한다. RSMC는 트리 기반 WMN를 형성하여 채널 다양성을 증가시키고, 다른 레이트를 사용하는 트리 위의 링크들을 채널로 분리시켜 RA를 줄인다. 또한, 노드 연결성을 증가하기 NC (Network Connectivity) 알고리즘을 사용한다. 시뮬레이션을 통해 RSMC이 기존 멀티 채널 프로토콜보다 총 처리율, 노드 연결성, 채널 다양성 측면에서 향상된 성능을 보임을 입증하였다.

• Geosystem Engineering
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• 제21권5호
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• pp.262-272
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• 2018

The U-statistic method is one of the most important structural methods to separate the anomaly from background. It considers the location of samples and carries out the statistical analysis of the data without judging from a geochemical point of view and tries to separate subpopulations and determine anomalous areas. In the present study, 3D U-statistic method has been applied for the first time through the three-dimensional (3D) modeling of an ore deposit. In order to achieve this purpose, 3D U-statistic is applied on the data (Fe grade) resulted from the drilling network in Baghak mine, central part of the Sangan iron mines (in Khorassan Razavi Province, Iran). Afterward, results from applying 3D U-statistic method are used for 3D modeling of the iron mineralization. Results show that the anomalous values are well separated from background so that the determined samples as anomalous are not dispersed and according to their positioning, denser areas of anomalous samples could be considered as anomaly areas. And also, final results (3D model of iron mineralization) show that output model using this method is compatible with designed model for mining operation. Moreover, seen that U-statistic method in addition for separating anomaly from background, could be very efficient for the 3D modeling of different ore type.

• 약학회지
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• 제22권4호
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• pp.233-237
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• 1978

We studied on the separation of $\alpha$- and $\beta$-chain globins, the conditions of paper electrophoresis and mobility of globins in paper electrophoresis to determine their chain anomaly. Acidic-acetone mothod of Wilson and Smith was found to be more effecient for separating $\alpha$- and $\beta$chain globions than trichloroacetic acid method of Hayashi. The conditions of paper electrophoresis were current of 20v/cm and 0.6mA/cm for three hours at room temperature. In paper electroporesis, the mobility of $\alpha$- -chain globin towards the cathode was greater than that of $\beta$-chain globin. The results showed tha tchain anomaly of $\alpha$- and $\beta$-chain globins can be determined by the method of paper electrophoresis.

• 전기학회논문지
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• 제56권8호
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• pp.1412-1417
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• 2007

Magnetic anomaly generated around a ship is mainly due to the permanent magnetization(PM) and induced magnetization (IM) remaining on the hull. It is very difficult to predict the direction and its magnitude of the permanent magnetization distributed over the hull, that is caused by mechanical or thermal stress. In this paper, an effective method is proposed to separate two components, the one produced by PM and the other by IM, from the underwater earth field signal distorted by the ferromagnetic material of the ship. The method can easily provide the two kinds of magnetic anomaly through exploiting experimental results and 3D electromagnetic field analyses even though the PM distribution on the hull is not known. To validate the proposed method, a model ship is manufactured and tested. The results would be of much help to basis research for securing safe navigation of a ship against dangerous factors in underwater.

• Ocean Science Journal
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• 제41권1호
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• pp.1-10
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• 2006

Total sea surface temperature (SST) in a coupled GCM is diagnosed by separating the variability into signal variance and noise variance. The signal and the noise is calculated from multi-decadal simulations from the COLA anomaly coupled GCM and the interactive ensemble model by assuming both simulations have a similar signal variance. The interactive ensemble model is a new coupling strategy that is designed to increase signal to noise ratio by using an ensemble of atmospheric realizations coupled to a single ocean model. The procedure for separating the signal and the noise variability presented here does not rely on any ad hoc temporal or spatial filter. Based on these simulations, we find that the signal versus the noise of SST variability in the North Pacific is significantly different from that in the equatorial Pacific. The noise SST variability explains the majority of the total variability in the North Pacific, whereas the signal dominates in the deep tropics. It is also found that the spatial characteristics of the signal and the noise are also distinct in the North Pacific and equatorial Pacific.

• Journal of Chest Surgery
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• 제27권4호
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• pp.259-265
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• 1994

Cor triatriatum is a relatively rare cardiac anomaly, whose major feature is a fenestrated membrane separating an upper common pulmonary venous chamber from a lower true left atrial cavity. Interatrial communications may be present between the right atrium and the common pulmonary venous chamber or the true left atrium. From April 1981 to April 1992, 24 patients with cor triatriatum were treated at Seoul National University Hospital. Ages ranged from 1 month to 24 years with mean of 7.4 years. Twenty patients had interatrial communications through a patent foramen ovale, primum or secundum defect of the atrial septum. Four had no interatrial communications. Fourteen patients had associated anomalies; partial anomalous pulmonary venous connection in 3, total anomalous pulmonary venous connection in 2, persistent left superior vena cava in 3, and other anomalies in 6 patients. Surgical corrections were performed through right atriotomy in 18 patients, left atriotomy in 4, and both atriotomy in 2. Three patients [12.5%] died early after operation; two of them were associated with single ventricle. Six out of 21 survivors [28.6%] experienced complications; recurrent pneumonia, pulmonary embolism, ischemic encephalopathy, diaphragmatic palsy and tachyarrhythmias. At the time of follow up, all survivors, except one, were in functional class I. Surgical correction of cor triatriatum restored normal hemodynamic status with relatively low operative mortality, especially in patients not complicated with severe anomalies. This report summarizes the clinical diagnosis, associated anomalies, interatrial communications, surgical approach and late result of 24 patients underwent surgical corrections in our hospital.

• 자원환경지질
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• 제28권6호
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• pp.599-612
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• 1995

Some REE ore deposits are located in the middle part the of Korean peninsula. Geotectonically, the REE ore deposits situated on the Kyemyeongsan Formation of northern margin of the Okcheon geosynclinal belt and in the transitional zone between Kyeonggi massif and the Okcheon belt, with a deep-seated fracture separating the two tectonic units. The Kyemyeongsan Formation are different in lithology and metamorphic grade from the Gyeonggi massif and the Okcheon super group. The sequence of Kyemyeongsan Formation is dominantly composed of acidic metavolcanic and volcaniclastic rocks associated with alkaline igneous rocks which are related to volcano-plutonism. The REE ore deposits contain mainly Ce-La, Ta-Nb, Y, Y-Nd and Nd-Th group minerals. More than 15 RE and REE minerals have been found in the deposits, such as allanite, fergusonite, thorite bestnaesite, euxenite, polyclase, monazite, columbite, (Nb)-rutile, okanoganite, sphene, zircon, illmenite and some other unknown minerals. According to the characteristics of the mineral association, the REE ore deposits may be divided into 4 ore types; Zircon-REE, allanite-REE, feldspar-REE and fluorite-REE type. The Sm-Nd isochron age of the REE ore is 330 Ma, and the Sm-Nd model age is 1.11 Ga with ${\varepsilon}_{Nd(t)}$ being - 2.9. This data suggest that the REE ore deposit was formed in the early Carboniferous, and the ore-forming material came from the mantle. The REE ores show distinct light REE enrichment with strong negative Eu anomaly. The REE patterns of schistose rocks from Kyemyeongsan Formation are similar to felsic volcanics from rifts or back arc basins in or near continental crust. The genesis of the REE ore deposit is quite complicated. Different geologic processes are displayed in the studied area; sedimentation, volcanic activity, metamorphism and hydrothermal replacement. Alkali granite has suffered extensive post-magmatic metasomatism of a high temperature to produce alkali metasomatites. Geochemical charateristics show that metasomatism of alkaline fluid was probably the dominant ore-forming process in Chungju district.

• 한국지능시스템학회논문지
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• 제15권3호
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• pp.282-288
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• 2005

본 논문에서는 기존의 침입탐지 모델인 오용탐지 모델과 비정상 탐지 모델의 장점은 유지하되 단점은 보완하는 견지에서 새로운 침입탐지 모델을 제안한다. MMIDS로 명명된 새로운 침입탐지시스템은 다음의 평가 기준들을 모두 만족하는 차원에서 설계되었다: 1) 시스템에서 학습되지 않은 새로운 공격 유형의 신속한 발견; 2) 탐지된 공격 유형에 대한 세부적 정보의 제공; 3) 빠르고 효율적인 학습 및 갱신으로 인한 경제적인 시스템의 유지/보수; 4) 시스템의 점증성(incrementality) 및 확장성. MMIDS의 핵심 구성요소로 새롭게 제안된 다중 클래스 SVM은 빠르고 효율적인 학습 및 갱신이 가능하여 침입탐지 시스템의 유지보수 비용을 절감할 수 있다. 실험을 통해 유사한 공격 패턴에 대한 분류성능 및 각 공격 유형별 세분화 능력이 우수함을 보인다.