• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.285-285
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• 2016

Resistive random access memory devices have been widely studied due to their high performance characteristics, such as high scalability, fast switching, and low power consumption. However, fluctuation in operational parameters remains a critical weakness that leads to device failures. Although the random formation and rupture of conducting filaments (CFs) in an oxide matrix during resistive switching processes have been proposed as the origin of such fluctuations, direct observations of the formation and rupture of CFs at the device scale during resistive switching processes have been limited by the lack of real-time large-area imaging methods. Here, a novel imaging method is proposed for monitoring CF formation and rupture across the whole area of a memory cell during resistive switching. A hybrid structure consisting of a resistive random access memory and a light-emitting diode enables real-time monitoring of CF configuration during various resistive switching processes including forming, semi-forming, stable/unstable set/reset switching, and repetitive set switching over 50 cycles.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.2
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• pp.128-133
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• 2008

Phase-change random access memory (PRAM) chip cell phase of amorphous state is rapidly changed to crystal state above 160 Celsius degree within several seconds during Infrared (IR) reflow. Thus, on-board programming method is considered for PRAM chip programming. We demonstrated the functional 512Mb PRAM with 90nm technology using several novel core circuits, such as metal-2 line based global row decoding scheme, PN-diode cells based BL discharge (BLDIS) scheme, and PMOS switch based column decoding scheme. The reverse-state standby current of each PRAM cell is near 10 pA range. The total leak current of 512Mb PRAM chip in standby mode on discharging state can be more than 5 mA. Thus in the proposed BLDIS control, all bitlines (BLs) are in floating state in standby mode, then in active mode, the activated BLs are discharged to low level in the early timing of the active period by the short pulse BLDIS control timing operation. In the conventional sense amplifier, the simultaneous switching activation timing operation invokes the large coupling noise between the VSAREF node and the inner amplification nodes of the sense amplifiers. The coupling noise at VSAREF degrades the sensing voltage margin of the conventional sense amplifier. The merit of the proposed sense amplifier is almost removing the coupling noise at VSAREF from sharing with other sense amplifiers.

• Journal of the Korean Geographical Society
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• v.37 no.2
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• pp.131-142
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• 2002

The community and communal folk belief are developed as spatial phenomena. So the communal folk belief express the spatial perception of inhabitants in traditional village. This study analysis the spatial characteristics of communal folk belief in traditional village. The study area is Bangchon village which consists of seven hamlets in Changhung-gun, Chollanam-do. The reset are as follows. First, the seven hamlet\`s location process in Bangchon village has been developed with spatio-temporal variations since Korea dynasty. Second, the communal folk belief in study area can be classified as Ipsok, Byolsinje\`s site, Hojeby\`s site. Third, the spatial characteristics of communal folk belief in study area are indication of each hamlet\`s boundary, indication of entrance and exit of Bangchon visage, indication of central space of Bangchon village in traditional period. Consequently, the spatial distribution of communal for belief are important indicator about spatial structure and spatial perception in traditional village\`s society.

• Journal of Chest Surgery
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• v.28 no.11
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• pp.1014-1018
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• 1995

To confirm diagnosis and to set proper therapeutic strategy, open lung biopsies were done in 57 patients who were suspected for diffuse interstitial lung disease from January 1985 to December 1994. Among them, 35 were male and 22 were female[M:F=l.6: 1 and mean age of the patients is 53.5$\pm$ 2.3[24-81 years. Tissue for histologic studies were obtained from left lung in 33, from right lung in 24according to the distributions of the pathology. Preoperative diagnostic work-up`s were chest X-ray, CT[HRCT scan, sputum study, bronchoscopy[BAL, TBLB and PTNA and all of them were unsuccessful to confirm diagnosis. In comparison of pulmonary function tests between preoperative and postoperative values, there were no significant differences in FVC, FEV1, FEV1/FVC[p 0.05 but in AaDO2[p[0.05 . Postoperative complications including atelectasis, wound infection, pulmonary edema and respiratory insnfficiency, were shown in 5 cases[8.8% , and two of them were died of respiratory failure and sepsis[mortality rate 3.5% . Pathologic diagnosis was confirmed in 53 cases postoperatively but it was undetermined in 4[diagnostic yield rate 93.0% . In comparison between preoperative clinical diagnosis and postoperative pathologic diagnosis, new diagnosis were made in 17 cases[29.8% and preoperative tentative diagnosis were confirmed histologically in 36 cases[63.2% . In 4 cases[7.0% , however, diagnoses were not confirmed after biopsies. Therapeutic plans were reset in 46 cases[80.7% in accordance with the final diagnosis.In conclusion, open lung biopsy is recommended for a specific diagnosis and proper therapeutic plan in diffuse interstitial lung diseases because of its high diagnostic yield Irate and it`s relatively low morbidity and mortality rate in these tompromised patents.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.8
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• pp.1257-1264
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• 2013

The study is about the national defense 2020 plan. According to the reduction of military bases, It should be needed to be integrated as a high-tech camp. So we researched and did a fact-finding survey mainly in Gyeonggi Province. After the research, first, It should be reset the regional development planning and the retention criteria of harmonized camp. Second, the neglected and scrapped camps should be put into order to activate the local economy by handling procedure. Third, it should have dedicated consultative bodies, exclusive departments and professional staff to communicate with the military authorities and the citizens. Fourth, if there are any causes of civil appeals such as shooting ranges should be in the underground. Lastly, To get support smoothly, it should be reflected by enacted special laws and ordinance regulations. This material could be used when the Ministry of National Defense has a discussion with Gyeonggi Province.

• Journal of Power Electronics
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• v.7 no.4
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• pp.343-352
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• 2007

This paper proposes a modularized charge equalization converter for hybrid electric vehicle (HEV) lithium-ion battery cells, in which the intra-module and the inter-module equalizer are Implemented. Considering the high voltage HEV battery pack, over approximately 300V, the proposed equalization circuit modularizes the entire $M^*N$ cells; in other words, M modules in the string and N cells in each module. With this modularization, low voltage stress on all the electronic devices, below roughly 64V, can be obtained. In the intra-module equalization, a current-fed DC/DC converter with cell selection switches is employed. By conducting these selection switches, concentrated charging of the specific under charged cells can be performed. On the other hand, the inter-module equalizer makes use of a voltage-fed DC/DC converter for bi-directional equalization. In the proposed circuit, these two converters can share the MOSFET switch so that low cost and small size can be achieved. In addition, the absence of any additional reset circuitry in the inter-module equalizer allows for further size reduction, concurrently conducting the multiple cell selection switches allows for shorter equalization time, and employing the optimal power rating design rule allows fur high power density to be obtained. Experimental results of an implemented prototype show that the proposed equalization scheme has the promised cell balancing performance for the 7Ah HEV lithium-ion battery string while maintaining low voltage stress, low cost, small size, and short equalization time.

• Korean Institute of Interior Design Journal
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• v.23 no.5
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• pp.104-111
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• 2014

This study puts its purpose on presenting an integral system of representative urban landscapes, public design and colors, in practicing urban design in the context of local identity. An integral design of public design that successfully plans and executes local identity, and changes recognition of integral management of urban design, is suggested as followings. Firstly, when the catchment area is divided in metropolitan area, it should be reset according to the natural environment condition regardless of administrative area system like city and county. It is the method to classify the metropolitan area by researching and analyzing geographical condition, weather condition, soil and vegetation in detail and subclassify it by the visual commonness of natural environment. Secondly, it is necessary to access the urban landscape, public design and urban color from the overall aspect emphasizing the plan for each field and local identity. They should be practiced by the role and category of each field on the basis of consistent design strategy and instruction but the cooperation system is required as a process to reinforce and specify the mutual limit. Thirdly, the artificial structure is constructed through artificial adjustment depending on the urban formation process and the development time point. Therefore, it is necessary to pay attention to the rapid urban development, the change speed and the landscape formation of each age. It is necessary to classify the type of artificial landscape by age and form similarity and separate the area that should be generalized and controlled by entire metropolitan area form the area that should be specialized by basic local government.

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.266-271
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• 2017

In this study, we tried to improve the reproducibility of signal intensity by applying DOTS method. The study was conducted on 30 patients who had undergone hepatic screening because of poor reproducibility and decreased signal intensity. The images were acquired before and after injection of contrast media and then post-processed by DOTS methods. Signal intensity was compared and evaluated. The results showed that the signal intensity of the images was 183.3% ($1038.0{\pm}70.7$ before application, $2940.7{\pm}179.6$ after application) and 1118.4% ($444.1{\pm}92.4$, $5410.5{\pm}168.4$ after application). This is a significant improvement in the fact that the reproducibility of MRI) was changed by the DOTS method, which is a post-processing method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.6
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• pp.89-98
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• 2010

Isolated boost converter is desirable in the dc/dc converter applications where isolation is required and extremely high step up is needed. Transformer used to step up low input voltage into high output voltage must satisfy the volt-sec balance condition. Conventional isolated boost converter is controlled with conducting intervals overlapping. In this case, there is a problem that control circuit is complicated. In this paper, it is proposed and analyzed the isolated boost converter which set up a reset winding for the volt-sec balance of transformer and can construct the control circuit simple by using a self-driven switch. Finally, the validity of the theoretical analyses for the proposed converter is verified by both simulations and experiments on the 10[W] class isolated boost converter.

• Korean Journal of Optics and Photonics
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• v.23 no.4
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• pp.143-146
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• 2012

All-optical data extraction, one of the key technologies for all-optical computing and optical communication to perform add-drop, packet switching, and data reset, etc., is experimentally demonstrated by using cross-gain modulation (XGM) of semiconductor optical amplifiers (SOAs). Also, all-optical data extraction based on numerical simulation is performed by using the VPI simulation tool. In this paper, the suggested optical system based on SOAs shows the potential for high speed, and highly integrable and low power optical data computing.