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71.
Changhyun Roh Ho‐Young Lee Sang‐Eun Kim Sung‐Kee Jo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(8):1130-1134
BACKGROUND: Over 170 million people, more than 3% of the world's population, suffer from the hepatitis C virus (HCV) infection and the rate of death from liver‐related mortality to HCV has increased. In respect of this, the development of assays for biological imaging should be urgently considered as an essential factor in diagnosis. RESULTS: A novel HCV‐detecting technique using a nanoparticle‐supported aptamer probe was demonstrated. With the aid of nanoparticle quantum dots (QDs) with carboxyl group as an imaging probe, and 5′‐end‐amine‐modified RNA oligonucleotide as a capturing probe, target HCV NS3 was visually detected on chip. The QDs‐based RNA aptamer for HCV NS3 showed high selectivity and specificity against other protein such as BSA. The detection limit of HCV NS3 protein was 5 ng mL?1 level. CONCLUSION: With a novel strategy for protein–aptamer interaction, the feasibility of applying QDs‐based fluorescent detection technique to HCV viral protein assay for the development of a protein biochip was demonstrated. This scheme of QDs‐mediated imaging with a target‐oriented specific RNA aptamer for the detection of infectious HCV diseases provides an efficient strategy and a promising new platform for monitoring applications. Copyright © 2010 Society of Chemical Industry 相似文献
72.
A new design concept for diffusion barriers in high‐density memory capacitors is suggested, and both RuTiN (RTN) and RuTiO (RTO) films are proposed as sacrificial oxygen diffusion barriers. The newly developed RTN and RTO barriers show a much lower sheet resistance than various other barriers, including binary and ternary nitrides (reported by others), up to 800 °C, without a large increase in the resistance. For both the Pt/RTN/TiSix/n++poly‐plug/n+ channel layer/Si and the Pt/RTO/RTN/TiSix/n++poly‐plug/n+ channel layer/Si contact structures, contact resistance—the most important electrical parameter for the diffusion barrier in the bottom electrode structure of capacitors—was found to be as low as 5 kohm, even after annealing up to 750 °C. When the RTN film was inserted as a glue layer between the bottom Pt electrode layer and the TiN barrier film in the chemical vapor deposited (Ba,Sr)TiO3 (CVD–BST) simple stack‐type structure, the RTN glue layer was observed to be thermally stable to temperatures 150 °C higher than that to which the TiN glue layer is stable. Moreover, the capacitance of the physical vapor deposited (PVD)–BST simple stack‐type structure adopted TiN glue layer initially degraded after annealing at 500 °C, and, thereafter, completely failed. In the case of the RTN and RTO/RTN glue layers, however, the capacitance continuously increased up to 550 °C. Thus, the new RTN and RTO films, which act as diffusion barriers to oxygen, are very promising materials for achieving high‐density capacitors. 相似文献
73.
Jong-Won Roh 《Information Processing Letters》2008,109(1):1-12
Time sequences, which are ordered sets of observations, have been studied in various database applications. In this paper, we introduce a new class of time sequences where each observation is represented by an interval rather than a number. Such sequences may arise in many situations. For instance, we may not be able to determine the exact value at a time point due to uncertainty or aggregation. Such observation may be represented better by a range of possible values. Similarity search with interval time sequences as both query and data sequences poses a new challenge for research. We first address the issue of (dis)similarity measures for interval time sequences. We choose an L1 norm-based measure because it effectively quantifies the degree of overlapping and remoteness between two intervals, and is invariant irrespective of the position of an interval when it is enclosed within another interval. We next propose an efficient indexing technique for fast retrieval of similar interval time sequences from large databases. More specifically, we propose: (1) to extract a segment-based feature vector for each sequence, and (2) to map each feature vector to either a point or a hyper-rectangle in a multi-dimensional feature space. We then show how we can use existing multi-dimensional index structures such as the R-tree for efficient query processing. The proposed method guarantees no false dismissals. Experimental results show that, for synthetic and real stock data, it is superior to sequential scanning in performance and scales well with the data size. 相似文献
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Youngjae Jung Quanzhen Duan Jeongjin Roh 《Analog Integrated Circuits and Signal Processing》2013,76(2):261-265
This paper presents a single-electrode capacitive sensor using a single-bit second-order incremental delta–sigma architecture. In order to achieve high accuracy in this capacitance-to-digital converter (CDC), the shielding signal and the digitally controlled offset capacitors are used in combination with the delta–sigma CDC. The designed sensor is suitable for capacitive transducers for ±10 pF input range with sub-fF resolution. 相似文献
76.
Jae Seong Roh Hong Sun Ryou Won Hee Park Yong Jun Jang 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2009,24(4):447-453
Fire is a major risk in the event of subway train fire due to coincidence with direction of smoke flow and evacuation. As a part of an effort to improve the life safety in a train fire, the platform screen door (PSD) is more and more installed on the ground that PSD provides a lot of benefits to passenger’s safety. Therefore, the investigation of effect of PSD on life safety is needed. In this study, fire simulation and evacuation simulation are performed to estimate the effect of PSD and ventilation on passenger’s life safety in a subway train fire. The Fire Dynamics Simulator (FDS V406) code is used to predict smoke spread and the available safe egress time during the fire. The evacuation of a subway station due to a train fire is simulated to predict the time required for evacuation, obtaining travel speed as a function of density. The passengers in platform with PSD and ventilation system have much more available time of about 350 s than passengers in case without PSD and ventilation system in modeled subway station. The subway turnstiles (ticket gate) dramatically increase the time required for evacuation without moving toward exits and bring passenger’s life safety danger in a subway train fire. 相似文献
77.
Vo-Gia Loc Se-goh Roh Ig Mo Koo Duc Trong Tran Ho Moon Kim Hyungpil Moon Hyouk Ryeol Choi 《Robotics and Autonomous Systems》2010,58(5):666-675
In this paper, a general study on improving adaptability of quadruped walking and climbing robot in complex environment is presented. First, a sensing system composed of range and gyroscope sensors in a novel arrangement is developed. By combining the sensing signals and the internal state of the robot, the surface geometry of the environment is sufficiently reconstructed in real-time. Secondly, a planning algorithm for the robot to overcome the reconstructed environment is conducted. Based on the reshaped surface, the planning algorithm not only provides the exact body trajectory and foot positions but also the adaptability of the robot in a specific environment. A method to improve the adaptability of the walking and climbing robot is also introduced. Thanks to the adherent ability of the robot, the center of gravity of the robot is allowed to move outside the support polygon to increase the reach-ability of the next swing leg. Finally, the effectiveness of the proposed approach is verified by the performances of the experiments in complex environments using a quadruped walking and climbing robot named MRWALLSPECT IV. 相似文献
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80.
Jongdae Kim Tae Moon Roh Kyoung-Ik Cho Jungling K.C. 《Electron Devices, IEEE Transactions on》2001,48(5):852-857
The optical emission spectra (180-700 nm) of plasma produced by a semiconductor bridge (SCB) with aluminum or tungsten electrodes have been measured and analyzed. The spatially and temporally resolved emission spectra of the SCB device have provided insights into the dynamic discharge of the bridge. The plasma electron temperature of the SCB device was measured using the comparison of the continuum emission of the bridge with the calculated optical emission spectra for a gray body source. Measured electron temperatures in the plasma produced by the bridges are related to the capacitor discharging voltage. The best estimates indicate that 4100-5500 K was measured for Al-electrode SCB device and 5650-6000 K for W-electrode SCB device 相似文献