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Rapid Determination of Imatinib in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry: Application to a Pharmacokinetic Study

  • Yang, Jeong Soo;Cho, Eun Gi;Huh, Wooseong;Ko, Jae-Wook;Jung, Jin Ah;Lee, Soo-Youn
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2425-2430
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    • 2013
  • A simple, fast and robust analytical method was developed to determine imatinib in human plasma using liquid chromatography-tandem mass spectrometry with electrospray ionization in the positive ion mode. Imatinib and labeled internal standard were extracted from plasma with a simple protein precipitation. The chromatographic separation was performed using an isocratic elution of mobile phase involving 5.0 mM ammonium formate in water-5.0 mM ammonium formate in methanol (30:70, v/v) over 3.0 min on reversed-stationary phase. The detection was performed using a triple-quadrupole tandem mass spectrometer in multiple-reaction monitoring mode. The developed method was validated with lower limit of quantification of 10 ng/mL. The calibration curve was linear over 10-2000 ng/mL ($R^2$ > 0.99). The method validation parameters met the acceptance criteria. The spiked samples and standard solutions were stable under conditions for storage and handling. The reliable method was successfully applied to real sample analyses and thus a pharmacokinetic study in 27 healthy Korean male volunteers.

Discrete Optimization of Unsymmetric Composite Laminates Using Linear Aproximation Method (선형 근사화방법을 이용한 비대칭 복합 적층평판의 이산최적화)

  • 이상근;구봉근;한상훈
    • Computational Structural Engineering
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    • v.10 no.2
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    • pp.255-263
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    • 1997
  • The optimum design of most structural systems used in practice requires considering design variables as discrete quantities. The present paper shows that the linear approximation method is very effective as a tool for the discrete optimum designs of unsymmetric composite laminates. The formulated design problem is subjected to a multiple in-plane loading condition due to shear and axial forces, bending and twisting moments, which is controlled by maximum strain criterion for each of the plys of a composite laminate. As an initial approach, the process of continuous variable optimization by FDM is required only once in operating discrete optimization. The nonlinear discrete optimization problem that has the discrete and continuous variables is transformed into the mixed integer programming problem by SLDP. In numerical examples, the discrete optimum solutions for the unsymmetric composite laminates consisted of six plys according to rotated stacking sequence were found, and then compared the results with the nonlinear branch and bound method to verify the efficiency of present method.

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A Study on the Improvement of Record and Archives Training in the National Archives of Korea (국가기록원의 기록관리교육에 대한 개선방안 연구)

  • Si, Kwisun
    • Journal of Korean Society of Archives and Records Management
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    • v.11 no.1
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    • pp.23-45
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    • 2011
  • In most countries, the national archives and universities operate educational programs and training courses for present and future records managers and archivists. In Korea, records management and archival training has been provided by the National Archives of Korea(NAK) and multiple graduate programs in archival studies. Records management and archival training programs in the NAK affect directly on the quality of the records and archives management in the public agencies and further on the records and archives management in general. In this paper, I presented a general overview of the records management and archival training programs in the NAK which focus on continuing professional education for the records managers in the public agencies. While presenting some key issues in the training programs, I also suggested some solutions and alternatives for the improvement and expansion of the training programs of the NAK. I suggested an expansion and diversification of the scope and contents of the training programs which would include training of records creators in the public sector and records managers and archivists in the private sector.

Bioequivalence Approaches for Highly Variable Drugs: Issue and Solution (개체 변이가 큰 약물 (highly variable drug)의 생물학적동등성 시험을 위한 실험설계 및 평가방법)

  • Baek, In-Hwan;Seong, Soo-Hyeon;Kwon, Kwang-Il
    • Korean Journal of Clinical Pharmacy
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    • v.19 no.1
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    • pp.50-60
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    • 2009
  • Highly variable drugs (within-subject variability greater than 30%) have been difficult to meet current regulatory acceptance criteria using a reasonable number of study subjects. In this study, we reviewed previous studies presenting alternative approaches for bioequivalence evaluation of highly variable drugs, and focused on an approach for widening the bioequivalence acceptance limits using within-subject variability. We discussed the suggested five solutions for highly variable drug including the deletion of $C_{max}$ of the bioequivalence criteria, direct expansion of bioequivalence limit, multiple dose studies in steady state, bioequivalence assessment on the metabolite, add-on study, and widening the bioequivalence acceptance limits based on reference variability. The methods for widening of bioequivalence limits based on reference variability are scaled average bioequivalence containing within-subject variability on reference drug (${\sigma}_{WR}$), population bioequivalence derived from total variability on reference drug (${\sigma}_{TR}$) and test drug (${\sigma}_{TT}$), and individual bioequivalence derived from subject by formulation interaction variability (${\sigma}_D$) and within subject variability on reference drug (${\sigma}_{WR}$) and test drug (${\sigma}_{TR}$). To apply these methods, the switching variability (${\sigma}_0$) will have to be set by the regulatory authorities. The proposals of bioequivalence evaluation approach for the highly variable in Korea are presented for both of new drug and reevaluation drug.

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Regional Information-based Route Optimization Scheme in Nested Mobile Network (중첩된 이동 네트워크 환경에서 지역적 정보를 이용한 경로 최적화 방안)

  • Kim Joon woo;Park Hee dong;Lee Kang won;Choi Young soo;Cho You ze;Cho Bong kwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4B
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    • pp.178-185
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    • 2005
  • NEMO basic support is a solution that provides network mobility in the Internet topology. Yet, when multiple mobile networks are nested, this basic solution suffers ken pinball-routing and a severe routing overhead. Therefore, several solutions for route optimization in a nested mobile network have already been suggested by the IETF NEMO WG. However, the current paper proposes Regional Information-based Route Optimization (RIRO) in which mobile routers maintain a Nested Router List (NRL) to obtain next-hop information, and packets are transmitted with a new routing header called an RIRO Routing Header (RIRO-RH). We showed that RIRO had the minimum packet overhead that remained constant, irrespective of how deep the mobile network was nested, in comparison with two earlier proposed schemes - Reverse Routing Header (RRH) and Bi-directional tunnel between HA and Top-Level mobile router (BHT).

Improving RFID Anti-Collision Algorithms with Multi-Packet Reception (다중 패킷 수신을 이용한 RFID 충돌방지 알고리즘의 성능 향상)

  • Lee, Jeong-Keun;Kwon, Taek-Young;Choi, Yang-Hee;Kim, Kyung-Ah
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.11A
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    • pp.1130-1137
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    • 2006
  • One of the important performance issues in large-scale RFID systems is to resolve collisions among responses from RFID tags. Considering two do facto anti-collision solutions, namely the binary-tree splitting algorithm and the Slotted-Aloha algorithm, we propose to use multi-packet reception (MPR) capability to enhance the RFID tag reading rate (i.e., throughput). MPR allows an RFID reader to receive multiple reponses transmitted by tags at the same time. We analyze the effect of MPR capability in the above anti-collision algorithms, which is also validated by simulation. The analysis and simulation results show that RFID reader antenna design and signal separation techniques play an important role in improving RFID system performance with MPR capability.

Energy Efficient Wireless Sensor Networks Using Linear-Programming Optimization of the Communication Schedule

  • Tabus, Vlad;Moltchanov, Dmitri;Koucheryavy, Yevgeni;Tabus, Ioan;Astola, Jaakko
    • Journal of Communications and Networks
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    • v.17 no.2
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    • pp.184-197
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    • 2015
  • This paper builds on a recent method, chain routing with even energy consumption (CREEC), for designing a wireless sensor network with chain topology and for scheduling the communication to ensure even average energy consumption in the network. In here a new suboptimal design is proposed and compared with the CREEC design. The chain topology in CREEC is reconfigured after each group of n converge-casts with the goal of making the energy consumption along the new paths between the nodes in the chain as even as possible. The new method described in this paper designs a single near-optimal Hamiltonian circuit, used to obtain multiple chains having only the terminal nodes different at different converge-casts. The advantage of the new scheme is that for the whole life of the network most of the communication takes place between same pairs of nodes, therefore keeping topology reconfigurations at a minimum. The optimal scheduling of the communication between the network and base station in order to maximize network lifetime, given the chosen minimum length circuit, becomes a simple linear programming problem which needs to be solved only once, at the initialization stage. The maximum lifetime obtained when using any combination of chains is shown to be upper bounded by the solution of a suitable linear programming problem. The upper bounds show that the proposed method provides near-optimal solutions for several wireless sensor network parameter sets.

PAPR Reduction Scheme Using Selective Mapping in GFDM (선택사상기법을 이용한 GFDM의 최대전력 대 평균전력 비 감소기법)

  • Oh, Hyunmyung;Yang, Hyun Jong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.6
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    • pp.698-706
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    • 2016
  • Orthogonal frequency division multiplexing (OFDM) has high peak to power ratio (PAPR). High PAPR makes problems such as signal distortion and circuit cost increasing. To solve the problemsm several PAPR reduction methods have been proposed. However, synchronization and orthogonality in OFDM systems may be a limitation to reduce latency for 5G networks. Generalized frequency division multiplexing (GFDM) is one of the possible solutions for asynchronous and non-orthogonal systems, which are more preferable to reduce the latency. However, multiple subsymbols in GFDM result in more superposition in time domain, GFDM has higher PAPR. Selective mapping (SLM) is one of PAPR reduction techniques in OFDM, which uses phase shift. The PAPR of GFDM SLM is compared to conventional GFDM and OFDM SLM in terms of PAPR reduction enhancement via numerical simulations. In addition, the out-of-band performance is analyzed in the aspect of asynchronous condition interference.

A Genetic Algorithm Application to Scalable Management of Multimedia Broadcast Traffic in ATM LANE Network (ATM LANE에서의 멀티미디어 방송형 트래픽의 Scalable한 관리를 위한 유전자 알고리즘 응용)

  • Kim, Do-Hoon
    • The KIPS Transactions:PartC
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    • v.9C no.5
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    • pp.725-732
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    • 2002
  • Presented is a Genetic Algorithm (GA) for dynamic partitioning an ATM LANE(LAN Emulation) network. LANE proves to be one of the best solutions to provide guaranteed Quality of Service (QoS) for mid-size campus or enterprise networks with minor modification of legacy LAN facilities. However, there are few researches on the efficient LANE network operations to deal with scalability issues arising from broadcast traffic delivery. To cope with this scalability issue, proposed is a decision model named LANE Partitioning Problem (LPP) which aims at partitioning the entire LANE network into multiple Emulated LANs (ELANS), each of which works as an independent virtual LAN.

CdSe Nanocrystal Quantum Dots Based Hybrid Heterojunction Solar Cell

  • Jeong, So-Myung;Eom, S.;Park, H.;Lee, Soo-Hyoung;Han, Chang-Soo;Jeong, So-Hee
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.93-93
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    • 2010
  • Semiconductor nanocrystal quantum dots (NQDs) have recently attracted considerable interest for use in photovoltaics. Band gaps of NQDs can be tuned over a considerable range by varying the particle size thereby allowing enhance absorption of solar spectrum. NQDs, synthesized using colloidal routes, are solution processable and promise for a large-area fabrication. Recent advancements in multiple-exciton generation in NQD solutions have afforded possible efficiency improvements. Various architectures have attempted to utilize the NQDs in photovoltaics, such as NQD-sensitized solar cell, NQD-bulk-heterojuction solar cell and etc. Here we have fabricated CdSe NQDs with the band gap of 1.8 eV to 2.1 eV on thin-layers of p-type organic crystallites (1.61 eV) to realize a donor-acceptor type heterojuction solar cell. Simple structure as it was, we could control the interface of electrode-p-layer, and n-p-layer and monitor the following efficiency changes. Specifically, surface molecules adsorbed on the NQDs were critical to enhance the carrier transfer among the n-layer where we could verify by measuring the photo-response from the NQD layers only. Further modifying the annealing temperature after the deposition of NQDs on p-layers allowed higher conversion efficiencies in the device.

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