• Journal of Power Electronics
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• 제19권4호
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• pp.858-868
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• 2019

With the widespread use of modern clean energy, lithium-ion batteries have become essential as a more reliable energy storage component in the energy Internet. However, due to the difference in monomers, some of the battery over-charge or over-discharge in battery packs restrict their use. Therefore, a novel multiphase interleaved converter for reducing the inconsistencies of the individual cells in a battery pack is proposed in this paper. Based on the multiphase converter branches connected to each lithium battery, this circuit realizes energy transferred from any cell(s) to any other cell(s) complementarily. This flexible interlaced converter is composed of an improved bi-directional Buck-Boost circuit that is presented with its own available control method. A simulation model based on the PNGV model of fundamental equalization is built with four cells in PSIM. Simulation and experimental results demonstrate that converter and its control achieve simple and fast equalization. Furthermore, a comparison of traditional methods and the HNFABC equalization is provided to show the performance of the converter and the control of lithium-based battery stacks.

• Corrosion Science and Technology
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• 제21권1호
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• pp.32-40
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• 2022

The o-Vanillin - Glutamine Schiff base [2-Hydroxy-3-Methoxy BenzylidineCarbomyl) -2-Butanoic Acid] was examined for low carbon steel corrosion inhibition in acid media. Weight loss studies were carried out at three different temperatures to determine the inhibition efficiency (IE). Electrochemical impedance spectroscopy revealed that the charge transfer resistance controlled the corrosion reaction and Tafel polarization indicated that the Schiff base acts as mixed mode of inhibitor. SEM images were recorded for the surface morphology of the low carbon steel surface. DFT studies revealed corrosion control mechanisms using quantum chemical parameters such as E_HOMO, E_LUMO, energy gap (∆E), chemical Hardness (η), chemical Softness (σ), Electronegativity (χ), and the fraction of electron transferred (∆N), which is calculated using Gaussian software 09. The gas-phase geometry was fully optimized in the Density Functional Theory (DFT/B3LYP-6-31G (d)).The DFT results are in good agreement with the experimental results. All the results proved that the Schiff Base (2-Hydroxy-3-Metoxy BenzylidineCarbomyl) -2-Butanoic is a suitable alternative for corrosion inhibition of low carbon steel in acid media.

• 한국유기농업학회지
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• 제30권3호
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• pp.313-333
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• 2022

In Muju County, one of Korea's major apple producers, the regional agricultural cooperatives united together and invested to establish a cooperative joint business corporation in charge of the sales business. The corporation carried out the sales business transferred from the participating regional agricultural cooperatives. While the two participating cooperatives showed a marked difference in the degree of participation at the beginning of the business, the introduction of the agricultural product processing centers (APCs) and the participation of co-selection and shipment organizations and general farms helped settle this gap. In addition, commercialization through the APCs enhanced the market competitiveness of apples, which led to the stable securing of sales outlets. The corporation integrated the sales business in the county and this resulted in increased sales volume and sales revenue. Playing a leading role in introducing and cultivating new crops on a trial basis, the corporation demonstrated its potential as the main body of the joint sales business.

• 한국산업정보학회논문지
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• 제15권3호
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• pp.67-75
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• 2010

네트워크 리프로그래밍은 센서 필드에 배치된 센서 노드들의 효율적인 유지 보수를 위해 코드 업데이트와 오류 수정을 원격으로 수행할 수 있도록 하는 기술이다. 센서 노드들 간에 소량의 데이터를 전달하는 일반적인 무선 센서 네트워크 통신과는 달리 네트워크 리프로그래밍에서는 대용량 데이터의 신뢰성 있는 전달이 요구된다. 기존의 네트워크 리프로그래밍 기법은 신뢰성 있는 데이터 전달을 위해 데이터 손실 발생 시 복구를 위한 비용이 많이 들며 이로 인한 에너지 소모가 급증하는 문제점을 안고 있다. 본 논문에서는 센서 네트워크에 적합한 클러스터 기반의 리프로그래밍 기법을 제안한다. 센서 필드를 클러스터로 나누고 각 클러스터에 대표 노드를 선정하여 중복 전송과 불필요한 경쟁을 최소화함으로써 에너지 소모를 줄인다. 또한 테이블을 이용하여 노드들의 상태 정보를 통해 정확한 오류 복구를 수행함으로써 신뢰성을 높이고 있다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2014년도 추계학술대회
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• pp.581-584
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• 2014

본 논문에서는 에너지 분배 기능을 이용하여 MPPT(Maximum Power Point Tracking) 제어 기능을 구현한 마이크로 빛에너지 하베스팅 시스템을 제안한다. 소형 PV(Photovoltaic) 셀에서 출력되는 에너지와 전압 레벨은 작기 때문에 직접 MPPT 제어회로를 구동하기 어렵다. 따라서 제안된 회로에서는 시동회로를 사용하여 Vcp를 MPPT 제어회로를 구동하기 위해 필요한 전압까지 승압시킨다. Vcp가 원하는 전압 값에 도달하면 전압감지기가 이를 감지하여 PV 셀로부터 시동회로에 공급되는 에너지는 차단하고, 전력변환기에 에너지를 공급한다. Vcp가 감소하여 MPPT 제어회로가 동작하기 어렵게 되면 전력변환기로의 에너지 전달을 차단하고 시동회로를 다시 구동한다. 이렇게 에너지 분배 기능을 이용하여 시동회로와 전력변환기를 번갈아 동작시키면서 에너지를 수확하여 PMU(Power Management Unit)를 통해 부하에 전달한다. 제안된 회로는 0.35um CMOS 공정으로 설계 되었으며 모의실험을 통해 동작을 검증하였다. 설계된 회로의 칩 면적은 패드를 포함하여 $1430um{\times}1110um$이다.

• Korean Journal of Acupuncture
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• 제21권4호
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• pp.1-19
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• 2004

Objectives : To understanding biological mechanism of acupuncture therapy, we have proposed a hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, we studied the effects of electric change in $ST_{37}(+)\;and\;ST_{39}(-)$ generated by Tanchim (彈鍼) manipulation which was stimulated at $ST_{36}$ point. And compared with data on the changes of electric change from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric change in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. Results : In this experiments, the changes of electric change from the stimulation type of Tanchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver, the other was an electromyogram of the receiver. Conclusion : The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1680-1688
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• 2004

The information indicating device plays an important part in the information times. Recently, the classical CRT (Cathod Ray Tube) display is getting transferred to the LCD (Liquid Crystal Display) one which is a kind of the FPDs (Flat Panel Displays). The OLED (Organic Light Emitting Diodes) display of the FPDs has many advantages for the low power consumption, the luminescence in itself, the light weight, the thin thickness, the wide view angle, the fast response and so on as compared with the LCD one. The OLED has lately attracted considerable attention as the next generation device for the information indicators. And also it has already been applied for the outside panel of a mobile phone, and its demand will be gradually increased in the various fields. It is manufactured by the vapor deposition method in the vacuum state, and the uniformity of thin film on the substrate depends on the temperature distribution in the point-cell source. This paper describes the basic concepts that are obtained to design the point-cell source using the computational temperature analysis. The grids are generated using the module of AUTOHEXA in the ICEM CFD program and the temperature distributions are numerically obtained using the STAR-CD program. The temperature profiles are calculated for four cases, i.e., the charge rate for the source in the crucible, the ratio of diameter to height of the crucible, the ratio of interval to height of the heating bands, and the geometry modification for the basic crucible. As a result, the blowout phenomenon can be shown when the charge rate for the source increases. The temperature variation in the radial direction is decreased as the ratio of diameter to height is decreased and it is suggested that the thin film thickness can be uniformed. In case of using one heating band, the blowout can be shown as the higher temperature distribution in the center part of the source, and the clogging can appear in the top end of the crucible in the lower temperature. The phenomena of both the blowout and the clogging in the modified crucible with the nozzle-diffuser can be prevented because the temperature in the upper part of the crucible is higher than that of other parts and the temperature variation in the radial direction becomes small.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.59-59
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• 2010

Graphene is a 2-D sheet of $sp^2$-bonded carbon arranged in a honeycomb lattice. This material has attracted major interest, and there are many ongoing efforts in developing graphene devices because of its high charge mobility and crystal quality. Therefore clear understanding of the substrate effect and mechanism of synthesis of graphene is important for potential applications and device fabrication of graphene. In a published paper in J. Phys. Chem. C (2008), the effect of substrate on the atomic/electronic structures of graphene is negligible for graphene made by mechanical cleavage. However, nobody shows the interaction between Ni substrate and graphene. Therefore, we have studied this interaction. In order to studying these effect between graphene and Ni substrate, We have observed graphene synthesized on Ni substrate and graphene transferred on $SiO_2$/Si substrate through Raman spectroscopy. Because Raman spectroscopy has historically been used to probe structural and electronic characteristics of graphite materials, providing useful information on the defects (D-band), in-plane vibration of sp2 carbon atoms (G-band), as well as the stacking orders (2D-band), we selected this as analysis tool. In our study, we could not observe the doping effect between graphene and Ni substrate or between graphene and $SiO_2$/Si substrate because the shift of G band in Raman spectrum was not occurred by charge transfer. We could noticed that the bonding force between graphene and Ni substrate is more strong than Van de Waals force which is the interaction between graphene and $SiO_2$/Si. Furthermore, the synthesized graphene on Ni substrate was in compressive strain. This phenomenon was observed by 2D band blue-shift in Raman spectrum. And, we consider that the graphene is incommensurate growth with Ni polycrystalline substrate.

• 수산경영론집
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• 제14권1호
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• pp.19-43
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• 1983

Mankind has made traditional use of various ocean resources in such several forms as fish, plants food, means of transportation, and military purpose, followed by the recent exploitation of offshore subsoil or sea-bed minerals, energies, and utilization of ocean space. These available ocean resources come from the marine natural environment which has a distinct feature in view of the relationship between human wants and their capacity to meet them. Though these socially basic resources however bring forth the so-called scarcity or differential rent, their communal nature of ownership dissipates free gifts of nature endowed to society as a whole. Thus to maximize these rents and social welfare thereof, rents should be secured and preserved through a well-defined arrangements of property-ownership as well as appropriate comparison of competing uses of marine resources, taking full cognizance of their irreversible adverse effects of a specific choice on the alternatives. Here I showed the sources of rent yielded from the multiple uses of navigation, fishery, mariculture, minerals, and recreation site, and also summarized the presently widely-known analytic tool to measure these rents with emphasis on due care of the telescopic faulty of the appraiser in charge, viewed from the communal point, Finally, as communal property is in strict sense owned by the public at large, notwithstanding the restricted communal ownership at government or local governments control, effectiveness of competition I expect should be kept while transferring claims of these resources from the legal owner to private enterprise as well as while extracting their rent by her. In particular, various national or social objectives look forward to tile maximization of social efficiency. Discretionary system in noncompetitive method thus, is exceptionally suggested because of probable suspicion from the public whether these resources are transferred as a give away or not in discretion. And these realized rent payments, I propose, should be wisely taken advantage of in advancement of scientific research in marine nature to bring an incremental rent therefrom successively.

• 한국콘텐츠학회논문지
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• 제15권4호
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• pp.65-74
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• 2015

본 연구는 히치콕 영화 <The Man Who Knew Too Much(1956)>의 사운드를 퍼스의 기호학적 관점에서 다루고 있다. 본고는 기호학적 논의에 앞서 퍼스의 이론을 살펴보고, 대사, 배경소리, 음악으로 구성된 사운드의 3요소를 그가 제시한 기호의 부류에 따라 분석해 보았다. 음악은 음정을 통해 지표기호로서 감정을 나타내기도 하며, 일차성 범주의 악기소리는 내러티브적 요소로 작용하여 이차성의 발화기호로 전이되면서 역동적 대상이 되기도 한다. 또한, 낱말기호로서의 대사 한 단어는 영화에서 도상기호를 통해 암시적으로 대상을 재현하기도 하며, 지표기호로서의 배경소리와 음악은 영화의 긴장감을 높이는데 기여하고 있다. 한편, 병치관계의 두 다른 장르의 음악은 발화기호로서 서술적 기능을 담당하고 있다. 이렇듯, 히치콕에 있어 사운드는 컨텍스트에 따라 의미작용을 달리하는 기호학적 특질을 갖는다.