• Journal of Communications and Networks
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• v.12 no.2
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• pp.158-167
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• 2010

The energy efficiency of wireless infrastructure and terminals has been drawing renewed attention of late, due to their significant environmental cost. Emerging green communication paradigms such as cognitive radios, are also imposing the additional requirement of flexibility. This dual requirement of energy efficiency and flexibility poses new design challenges for implementing radio functional blocks. This paper focuses on the area vs. power trade-offs for the type of channel filters that are required in the digital frontend of a flexible, energy-efficient radio. In traditional CMOS circuits, increased area was traded for reduced dynamic power consumption. With leakage power emerging as the dominant mode of power consumption in nanoscale CMOS, these trade-offs must be revisited due to the strong correlation between area and leakage power. The current work discusses how the increased timing slacks obtained by increasing the parallelism can be exploited for overall power reduction even in nanoscale circuits. In this context the paper introduces the notion of 'area efficiency' and a metric for evaluating it. The proposed metric has also been used to compare the area efficiencies of different classes of time-shared filters.

• BMB Reports
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• v.39 no.6
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• pp.717-721
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• 2006

In vitro analyses of type I signal peptidase activities require protein precursors as substrates. Usually, these pre-proteins are expressed in vitro and cleavage of the signal sequence is followed by SDS polyacrylamide gel electrophoresis coupled with autoradiography. Radioactive amino acids have to be incorporated in the expressed protein, since the amount of the in vitro expressed protein is usually very low and processing of the signal peptide cannot be followed by SDS polyacrylamide gel electrophoresis alone. Here we describe a rapid and simple method to express large amounts of a protein precursor in E. coli. We have analyzed the effect of ionophors as well as of azide on the accumulation of expressed protein precursors. Azide blocks the function of SecA and the ionophors dissipate the electrochemical gradient across the cytoplasmic membrane of E. coli. Addition of azide ions resulted in the formation of inclusion bodies, highly enriched with pre-apo-plastocyanine. Plastocyanine is a soluble copper protein, which can be found in the periplasmic space of cyanobacteria as well as in the thylakoid lumen of cyanobacteria and chloroplasts, and the pre-protein contains a cleavable signal sequence at its N-terminus. After purification of cyanobacterial pre-apo-plastocyanine, its signal sequence can be cleaved off by the E. coli signal peptidase, and protein processing was followed on Coomassie stained SDS polyacrylamide gels. We are optimistic that the presented method can be further developed and applied.

• Journal of Broadcast Engineering
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• v.7 no.1
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• pp.37-44
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• 2002

In this paper. we propose a new video coding scheme with multi-resolution motion compensation and residual quantization. The main functional blocks of the proposed scheme include multi-level wavelet decomposition. motion estimation and motion compensation. raster scanning within each subband. formation of block trees and blocking partitioning. and adaptive arithmetic coding. Although the proposed ceding scheme is simple and requires low computational complexity, it produces bitstreams tilth good features. such as the embedded structure and SNR scalability. Experimental results demonstrate that the proposed coding scheme is quote competitive to and often outperforms other wavelet-based video coding schemes in the literature.

• The Korean Journal of Pain
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• v.28 no.1
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• pp.57-60
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• 2015

Sphincter of Oddi dysfunction (SOD) is a syndrome of chronic biliary pain or recurrent pancreatitis due to the functional obstruction of the pancreaticobiliary flow. We report a case of spinal cord stimulation (SCS) for chronic abdominal pain due to SOD. The patient had a history of cholecystectomy and had suffered from chronic right upper quadrant abdominal pain. The patient had been diagnosed as having SOD. The patient was treated with opioid analgesics and nerve blocks, including a splanchnic nerve block. However, two years later, the pain became intractable. We implanted percutaneous SCS at the T5-7 level for this patient. Visual analog scale (VAS) scores for pain and the amount of opioid intake decreased. The patient was tracked for more than six months without significant complications. From our clinical case, SCS is an effective and alternative treatment option for SOD. Further studies and long-term follow-up are necessary to understand the effectiveness and the limitations of SCS on SOD.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.472-474
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• 2014

Carbon nanotubes (CNTs) have been intensively investigated since they have been considered as building blocks of nanoscience and nanotechnology. Theoretical and computational studies on CNTs have revealed their physical and chemical properties and helped researchers build various experimental devices to study them in depth. However, there have been only few systematic studies on detailed changes in electronic structures of CNTs due to geometrical structure modifications. In this regard, it is necessary to perform systematic investigations of the modifications in electronic structures of CNTs, as their geometrical configurations are altered, using the first-principles density functional theory. In other words, it is essential to determine the true equilibrium structure of CNTs. We are going to construct different atomic configurations of each nanotube by maintaining the original symmetries, but changing all the other bonding types one by one. Furthermore, as for CNTs, for example, the way the graphene sheet is wrapped is represented by a pair of indices (n,m) and electronic structures of CNTs vary depending on different indices. Therefore, we plan to study and discuss all the significant couplings between electronic and geometric structures in CNTs.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.5
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• pp.672-679
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• 1999

This paper describes the design method of active bandpass filters which employ active impedance inverters. Several authors have reported active bandpass filters. However, the functional description of the active blocks in the filters have not been throughly studied. In this paper, the active inverter block of the bandpass filter has is analyzed in the view point of filter design. The designed 3-pole bandwidth filter has its insertion gain of 24 dB at the center frequency of 865 MHz with 75 MHz bandwidth. The noise figure of the active bandpass filter is less than 2.5 dB within its passband.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1940-1943
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• 2002

In this paper, we presented the design and implementation of 155Mbps satellite Modem adaptively compensated against the rain attenuation. In order to compensate the rain attenuation over high-speed satellite ink, the adaptive coding schemes with variable coding rates and the pragmatic TCM that can be decoded both the QPSK and TC-8PSK using same Viterbi decoder was studied and analyzed. The pragmatic TCM with rate 213, selected to the optimal parameters for implementation, was modeled by VHDL in this paper. The key design issues are how to achieve a high data rate and how to integrated into a single ASIC chip various functions such as the different data rates, Scrambler/descrambler, Interleaver, Encoder/decoder, and BPSK/QPSK/8PSK modulator/demodulator. The implemented 155M0ps adaptive MODEM has the simplified interface circuits among the many functional blocks, and parallel processing architecture to achieve the high data rate. This 155Mbps adaptive MODEM was designed and implemented by single ASIC chip with the 0.25 $\mu\textrm{m}$ CMOS standard cell technology.

• Convergence Security Journal
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• v.13 no.6
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• pp.3-9
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• 2013

With the rapidly changing information communication environment and development of technologies, the informati on networks are evolved from traditional fixed form to an active variable network that flexible large variety of data can be transferred. To reflect the needs of users, the next generation using DWDM (Dense Wavelength Division M ultiplexing) transmission system and OXC (Optical Cross Connect) form a dynamic network. After that GMPLS (Ge neralized Multi-Protocol Label Switching) can be introduced to dynamically manage and control the Reconfigurable Optical Add-drop Multiplexer (ROADM)/Photonic Cross Connect (PXC) based network. This paper propose a softw are architecture of Path Computation Element (PCE) protocol that has proposed by Internet Engineering Task Force (IETF) to path computation. The functional blocks and Application Programming Interface (API) of the PCE protoco l implementation are also presented.

• ETRI Journal
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• v.37 no.5
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• pp.833-844
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• 2015

Recently, new network systems have begun to emerge (for instance, 5G, IoT, and ICN) that require capabilities beyond that provided by existing IP networking. To fulfill the requirements, some new networking technologies are being proposed. The promising approach of the new networking technology is to try to overcome the architectural limitations of IP networking by adopting an identifier (ID)-based networking concept in which communication objects are identified independently from a specific location and mechanism. However, we note that existing ID-based networking proposals only partially meet the requirements of emerging and future networks. This paper proposes a new ID-based networking architecture and mechanisms, named IDNet, to meet all of the requirements of emerging and future networks. IDNet is designed with four major functional blocks-routing, forwarding, mapping system, and application interface. For the proof of concept, we develop numeric models for IDNet and implement a prototype of IDNet.

• Journal of the Korea Safety Management & Science
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• v.13 no.3
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• pp.45-53
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• 2011

The research proposes seven elimination rules of redundant gates and blocks in Fault Tree Analysis (FTA) and Reliability Block Diagram (RBD). The computational complexity of cut sets and path sets is NP-hard. In order to reduce the complexity of Minimal Cut Set (MCS) and Minimal Path Set (MPS), the paper classifies generation algorithms. Moreover, the study develops six implementation steps which reflect structural importance (SI) and reliability importance (RI) from Reliability Centered Maintenance (RCM) that a priority of using the functional logic among components is to reduce (improve) the system unavailability (or availability). The proposed steps include efficient generation of state structure function by Rare Event Enumeration (REA). Effective use of importance measures, such as SI and ill measures, is presented based on the number and the size of MCS and MPS which is generated from the reference[5] of this paper. In addition, numerical examples are presented for practitioners to obtain the comprehensive understanding of six steps that is proposed in this research.