• IE interfaces
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• v.7 no.3
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• pp.77-90
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• 1994

Recently, it has been widely conceived that Concurrent Enginering (CE) can provide a competitive edge for companies that have confronted with rapidly changing market requirements, such as shortening of product life-cycles, high quality and low cost products, diversity of customer demand, and so on. CE is generally recognized as a practice to bridge the gap between designing a product and other various life-cycle activities, such as manufacturing, assembly, testing, and maintenance, at an early stage of design. In this paper the concepts of CE is first overviewed, and many of its supporting tools are discussed. It is then proposed an architecture of a CE support system that can provide a unifying view of the tools. Finally, a case that has successfully implemented the concepts is presented.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.743-746
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• 1998

The Belousov-Zhabotinskii (BZ) reaction, which is composed of a bromate-organic acid-metal catalyst and an acidic solution is a commonly employed chemical oscillating reaction system. Cyclohexanedione (CHD) has been used as an initial organic substrate in oscillation systems. We studied each system of 1,4-CHD/BrO3-/Ce4/H+ and 1,3-CHD/BrO3-/Ce4+/H+ oscillating reactions, and studied the control of oscillating characters in a CHD/BrO3-/Ce4+/H+ batch system using a mixed substrate of 1,4-CHD and 1,3-CHD under a fixed total CHD concentration. In the mixed reactions, 1,4-CHD was used as a main substrate and small amounts of 1,3-CHD were used in order to vary the oscillatory behaviours by changing the mixing amount ratio of two substrates.

• Mycobiology
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• v.49 no.5
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• Journal of Advanced Information Technology and Convergence
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• v.6 no.1
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• pp.45-57
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• 2016

This paper proposes an adaptive channel estimation scheme for OFDM-based IEEE 802.11ad wireless local area network (WLAN). The standard supports two types of information of OFDM packets for estimating the communication channels, which are the channel estimation field (CEF) of preamble and pilot subcarriers. The CEF-based channel estimation provides better BER (bit error rate) performance at slow fading channel state, whereas the pilot-based channel estimation is good at fast fading channel state. Hence, a combined channel estimation method is introduced to improve the performance. The prediction of the channel state to select the proper channel estimation method is required. In this work, an adaptive channel estimation scheme is also proposed to improve the performance of channel estimation (CE). Basing on a channel quality indicator (CQI), the proper channel estimation method corresponding to the channel type is decided.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.221-224
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• 2000

The purposes of this paper are to clarify the influences of artifacts on a cerebrovascular audiospectroscopy (CeVASS) and to improve the detecting precision of the CeVASS. First, we perform the CeVASS in 15 healthy adults with various measuring positions such as forehead eyes, cervical parts, temple parts, and occipitomastoid parts, and the influences of artifacts on each position is estimated. Next, we discuss about the removal of the artifacts using cross-spectral analysis. Finally, we propose an improved system of the CeVASS.

• Biomedical Science Letters
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• v.22 no.4
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• pp.127-139
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• 2016

A species of the fungal genus Cordyceps has been used as an ingredient of traditional Chinese medicine. In this study, we prepared cordycepin-enriched WIB-801CE, an ethanol extract from culture solution of Cordyceps militaris-hypha, and evaluated its antiplatelet effects on human platelet aggregation. WIB-801CE dose-dependently inhibited ADP-, collagen-, and thrombin-induced platelet aggregation. These antiplatelet effects by WIB-801CE were associated with the attenuation of thromboxane $A_2$ ($TXA_2$) production and serotonin release by ADP, collagen, and thrombin. The inhibition of $TXA_2$ production by WIB-801CE was due to the inhibition of cyclooxygenase-1, $TXA_2$ synthase, and cytosolic phospholipase $A_2$ activity. Therefore, these data suggest that WIB-801CE may be a beneficial component against protection from platelet aggregation-mediated thrombotic disease.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.5
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• pp.227-231
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• 2005

We have developed a microsystem with a capillary electrophoresis (CE) and an electrochemical detector (ECD). The microfabricated CE-ECD systems are adequate for a disposable type and the characteristics are optimized for an application to the electrochemical detection. The system was realized with polydimethylsiloxane (PDMS)-glass chip and indium tin oxide electrode. The injection and separation channels (80 um wide$\ast$40 um deep) were produced by moulding a PDMS against a microfabricated master with relatively simple and inexpensive methods. A CE-ECD systems were fabricated on the same substrate with the same fabrication procedure. The surface of PDMS layer and ITO-coated glass layer was treated with UV-Ozone to improve bonding strength and to enhance the effect of electroosmotic flow. For comparing the performance of the ITO electrodes with the gold electrodes, gold electrode microchip was fabricated with the same dimension. The running buffer was prepared by 10 mM 2-(N-morpholino)ethanesulfonic acid (MES) titrated to PH 6.5 using 0.1 N NaOH. We measured olectropherograms for the testing analytes consisted of catechol and dopamine with the different concentrations of 1 mM and 0.1 mM, respectively. The measured current peaks of dopamine and catechol are proportional to their concentrations. For comparing the performance of the ITO electrodes with the gold electrodes, electropherograms was measured for CE-ECD device with gold electrodes under the same conditions. Except for the base current level, the performances including sensitivity, stability, and resolution of CE-ECD microchip with ITO electrode are almost the same compared with gold electrode CE-ECD device. The disposable CE/ECD system showed similar results with the previously reported expensive system in the limit of detection and peak skew. When we are using disposable microchips, it is possible to avoid polishing electrode and reconditioning.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.671-676
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• 1998

The formation and dissociation rates of $Ce^{3+}$ Complexes of the 1,4,7,10-tetraaza-13,16-dioxacyclooctadecane-NN', N",N"'-tetraacetic acid (1), 1,4,7,10-tetraaza-13,16-dioxacyclooctadecane-N,N',N",N"'-tetramethylacetic acid (2), and 1,4,7,10-tetraaza-13,16-dioxacyclooctadecane-N,N',N",N"'-tetrapropionic acid (3) have been measured by the use of stopped-flow spectrophotometry. Observations were made at 25.0±0.1 ℃ and at an ionic strength of 0.10 M $NaClO_4$. The complexation of $Ce^{3+}$ ion with 1 and 2 proceeds through the formation of an intermediate complex $(CeH_3L^{2+})^*$ in which the $Ce^{3+}$ ion is incompletely coordinated. This may then lead to be a final product in the rate-determining step. Between pH 4.76 and 5.76, the diprotonated $(H_2L^{2-})$ from is revealed to be a kinetically active species despite of its low concentration. The stability constants $(logK(CeH_3L^{2+}))$ and specific water-assisted rate constants $(k_{OH})$ of intermediate complexes have been determined from the kinetic data. The dissociation reactions of $Ce^{3+}$ complexes of 1, 2, and 3 were investigated with $Cu^{2+}$, ions as a scavenger in acetate buffer. All complexes exhibit acid-independent and acid-catalyzed contributions. The effect of buffer and $Cu^{2+}$ concentration on the dissociation rate has also been investigated. The ligand effect on the dissociation rate of $Ce^{3+}$ complexes is discussed in terms of the side-pendant arms and the chelate ring sizes of the ligands.

• PNF and Movement
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• v.16 no.3
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• pp.461-473
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• 2018

Purpose: The purpose of this study was to evaluate and compare the effects of inspiratory muscle training with chest expansion exercises on pulmonary function, maximal inspiratory pressure, and gait in individuals with stroke. Methods: The participants in this study included 36 stroke patients. These patients were randomly divided into three groups: an inspiratory muscle training (IMT) with chest expansion (CE) group (n=12), an IMT group (n=12), and a control group (n=12). Participants in the IMT with CE group underwent IMT and CE exercises 5 times per week for 30 minutes over 4 weeks, whereas those in the CE group and the control group received IMT and conventional physical therapy, respectively, for the same duration. The investigator measured the patients' pulmonary function, maximal inspiratory pressure, and gait endurance. Results: After the intervention, the change values for the forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal inspiratory pressure (MIP), and six-minute walk test (6MWT) in the IMT with CE group and the control group were significantly greater than those of the control group (p<0.05). Similarly, after the intervention, the change values of the FVC, FEV1, PEF, MIP, and 6MWT in the IMT with CE group were significantly greater than those in the IMT group (p<0.05). Conclusion: These findings suggest that IMT with CE could be used to increase pulmonary function, maximal inspiratory pressure, and gait endurance in stroke patients.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1C
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• pp.35-44
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• 2004

In this paper, we design an efficient VLSI architecture of entropy coding algorithm in JPEG2000. Entropy coder is a context-based binary arithmetic encoder, and composed of a Context Extractor(CE) and an Arithmetic Coder(AC). We speed-up CE by skipping no-operation bits in coding passes, and AC is to be performed based on MQ coder. Because of using Qe value associated with each allowed context and probability estimation, MQ coder is a multiplication free coder that reduces computation loads and makes simple the structure of arithmetic coder. We have developed and synthesized the VHDL models of CE and AC pairs using Xilinx FPGA technology. The proposed architecture operates up to 30MHz.