• Title/Summary/Keyword: Variable charge

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CCD Image Sensor with Variable Reset Operation

  • Park, Sang-Sik;Uh, Hyung-Soo
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.3 no.2
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    • pp.83-88
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    • 2003
  • The reset operation of a CCD image sensor was improved using charge trapping of a MOS structure to realize a loe voltage driving. A DC bias generating circuit was added to the reset structure which sets reference voltage and holds the signal charge to be detected. The generated DC bias is added to the reset pulse to give an optimized voltage margin to the reset operation, and is controlled by adjustment of the threshold voltage of a MOS transistor in the circuit. By the pulse-type stress voltage applied to the gate, the electrons and holes were injected to the gate dielectrics, and the threshold voltage could be adjusted ranging from 0.2V to 5.5V, which is suitable for controlling the incomplete reset operation due to the process variation. The charges trapped in the silicon nitride lead to the positive and negative shift of the threshold voltage, and this phenomenon is explained by Poole-Frenkel conduction and Fowler-Nordheim conduction. A CCD image sensor with $492(H){\;}{\times}{\;}510(V)$ pixels adopting this structure showed complete reset operation with the driving voltage of 3.0V. The resolution chart taken with the image sensor shows no image flow to the illumination of 30 lux, even in the driving voltage of 3.0V.

Electrical Characteristics of Engineered Tunnel Barrier using $SiO_2/HfO_2$ and $Al_2O_3/HfO_2$ stacks ($SiO_2/HfO_2$$Al_2O_3/HfO_2$를 이용한 Engineered Tunnel Barrier의 전기적 특성)

  • Kim, Kwan-Su;Park, Goon-Ho;Yoon, Jong-Won;Jung, Jong-Wan;Cho, Won-Ju
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.127-128
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    • 2008
  • The electrical characteristics of VARIOT (variable oxide thickness) with various $HfO_2$ thicknesses on thin $SiO_2$ or $Al_2O_3$ layer were investigated. Especially, the charge trapping characteristics of $HfO_2$ layer were intensively studied. The thin $HfO_2$ layer has small charge trapping characteristics while the thick $HfO_2$ layer has large memory window. Therefore, the $HfO_2$ layer is superior material and can be applied to charge storage as well as tunneling barrier of the non-volatile memory applications.

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Looking through the Mass-to-Charge Ratio: Past, Present and Future Perspectives

  • Shin, Seung Koo
    • Mass Spectrometry Letters
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    • v.12 no.4
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    • pp.126-130
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    • 2021
  • The mass spectrometry (MS) provides the mass-to-charge ratios of atoms, molecules, stable/metastable complexes, and their fragments. I have taken a long journey with MS to address outstanding issues and problems by experiments and theory and gain insights into underlying principles in chemistry. By looking through the mass-to-charge ratio, I have studied thermochemical problems in silicon chemistry, the infrared multiphoton dissociation spectroscopy of organometallic intermediates, unimolecular dissociations of halotoluene radical cations, and the kinetics of association/dissociation of alkali halide triple ions with Lewis bases. Various MS platforms have been used to characterize non-covalent interactions between porphyrins and fullerenes and those between the group IIB ions and trioctylchalcogenides, and to examine the binding of the group IA, IIA and porphyrin ions to G-quadruplex DNA. Recently, I have focused on mass-balanced H/D isotope dipeptide tags for MS-based quantitative proteomics, a simple chemical modification method for MS-based lipase assay, and the kinetics and dynamics of energy-variable collision-induced dissociation of chemically modified peptides. Now, I see an important role of MS in global issues in the post-COVID era, as the society demands high standards for indoor air quality to contain the airborne-pathogen transmission as well as in-situ monitoring and tracking of carbon emissions to reduce global warming.

Erasing characteristic improvement in SONOS type with engineered tunnel barrier (Engineered tunnel barrier를 갖는 SONOS 소자에서의 소거 속도 향상)

  • Park, Goon-Ho;You, Hee-Wook;Oh, Se-Man;Kim, Min-Soo;Jung, Jong-Wan;Lee, Young-Hie;Chung, Hong-Bay;Cho, Won-Ju
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.97-98
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    • 2009
  • Tunneling barrier engineered charge trap flash (TBE-CTF) memory capacitor were fabricated using the tunneling barrier engineering technique. Variable oxide thickness (VARIOT) barrier and CRESTED barrier consisting of thin $SiO_2$ and $Si_3N_4$ dielectrics layers were used as engineered tunneling barrier. The charge trapping characteristic with different metal gates are also investigated. A larger memory window was achieved from the TBE-CTF memory with high workfunction metal gate.

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On the Separation of the Rank-1 Chvatal-Gomory Inequalities for the Fixed-Charge 0-1 Knapsack Problem (고정비용 0-1 배낭문제에 대한 크바탈-고모리 부등식의 분리문제에 관한 연구)

  • Park, Kyung-Chul;Lee, Kyung-Sik
    • Journal of the Korean Operations Research and Management Science Society
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    • v.36 no.2
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    • pp.43-50
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    • 2011
  • We consider the separation problem of the rank-1 Chvatal-Gomory (C-G) inequalities for the 0-1 knapsack problem with the knapsack capacity defined by an additional binary variable, which we call the fixed-charge 0-1 knapsack problem. We analyze the structural properties of the optimal solutions to the separation problem and show that the separation problem can be solved in pseudo-polynomial time. By using the result, we also show that the existence of a pseudo-polynomial time algorithm for the separation problem of the rank-1 C-G inequalities of the ordinary 0-1 knapsack problem.

A Study on the Characteristic of High Voltage Type Instantaneous Current Source for Laser Printer (Laser 프린터용 고압 순시 전류제어형 전원특성에 관한 연구)

  • 채영민;조종화;권중기;한상용
    • The Transactions of the Korean Institute of Power Electronics
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    • v.9 no.2
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    • pp.105-111
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    • 2004
  • In this paper, a new self-oscillated type high voltage power supply for the OPC(Organic Photo Conductor) charge is proposed, which has variable constant current source characteristics to improve the charge characteristic of the OPC roller. The proposed control method enables high quality printing characteristics regardless of the circumstance change such as ambient temperature or humidity by changing the current reference signal. To verify the proposed control method various experiments are performed.

The Control Algorithm of Power-conditioner for Stand-alone PV System (독립형 PV시스템용 전력변환기 제어 알고리즘)

  • 정영석;강기환;김홍성;정명웅;유권종;송진수
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1998.10a
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    • pp.209-215
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    • 1998
  • This paper deals with stand-alone Photovoltaic system(SPVS) with charge and discharge controller. Main power source of SPVS are generally solar cell and battery. therefore SPVS can be classified into variable types in accordance with connection type between battery and solar cell. Mainly used one of them is direct connection type which has advantages such as simple structure and simple controller. However most big drawback of this system is energy loss by voltage disharmony between solar cell and battery. Therefore SPVS with charge and discharge controller which can operate solar cell at maximum power point is designed and analyzed by simulation in this paper.

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Cycle-by-Cycle In-cylinder HC & NOx Formation Characteristics with Port Masking in CVVT Engine (포트 마스킹과 흡기 밸브 타이밍이 실린더 내부의 싸이클별 HC와 NOx 생성에 미치는 영향)

  • Jeon, Woo-Ju;Choi, Kwan-Hee;Myung, Cha-Lee;Park, Sim-Soo;Lee, Kyung-Hwan
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.3108-3113
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    • 2008
  • This paper investigated the behaviors of combustion characteristics at part load condition with various intake charge motions induced by the port masking schemes in the CVVT (Continuously Variable valve Timing) engine. Time resolved in-cylinder and exhaust emissions were measured by the fast response HC and NOx analyzers to examine their formation mechanisms and behavior characteristics. As a result, in-cylinder HC decreased with the advanced intake valve timings but HC at the exhaust port increased due to the worse combustion stabilities. However HC reduction could be achieved by the application of the port maskings with a enhancement of the engine stability. NOx also decreased with early intake timings by internal EGR but increased with the charge motion controls which enhance the combustion behavior.

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The Effects of Empowerment on Job Satisfaction, Commitment, Culinary Staff in the Hotel (임파워먼트(Empowerment)가 호텔주방조직 구성원의 직무만족과 몰입에 미치는 영향에 관한 연구)

  • 김기영;염진철
    • Culinary science and hospitality research
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    • v.9 no.4
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    • pp.136-151
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    • 2003
  • The summarized analysis result of this research is as follows. First, regarding the difference of preceding variable and dependent variable, statistically considerable difference did not appear between self determination and personal relations in educational background and between groups of self determination in hotel type, and statistically considerable difference appeared among other groups. Second, regression analysis result between empowerment and job satisfaction turned out that statistically considerable influence is exerted in the order of personal relations ability, influence power, role performance ability and self-decision nature. Third, regression analysis result between empowerment and job devotion turned out that statistically considerable influence is exerted in the order of personal relations ability, role performance ability and influence power. Fourth, regression analysis result between empowerment and organization devotion turned out that statistically considerable result is exerted in the order of influence power and personal relations ability. Fifth, it turned out that statistically relative high correlation existed among correlation of empowerment and result variable such as job satisfaction, job devotion and organization devotion. The above-mentioned matters considered, this research proposes following points. This research examines the effect of empowerment on job satisfaction and organizational commitment of culinary staff in the hotel. the effect of the variable of empowerment on result variable shows that role performance ability, influence power and personal relations ability are important variables. Therefore, to improve the role performance ability of members of kitchen, it is essential for each individual to improve their ability and to have confidence at the time of business performance. So, this research implies that consistent and systematic training is necessary for increasing the ability and confidence. In order to improve influence power, it is necessary for members of an organization to have strong faith that their jobs determine the success of the company, and to increase the sense of self-control by letting them have the right of self determination, so that all members may have strong desire to transact business. This research implies that in order to improve personal relations ability, it is necessary for members of an organization to discover the best method of decision-making and solve problems through members' developing mutual action, and for managers to take personal characteristics into account so that members may have belief and confidence in their job and realize the value of their job. In conclusion, the person in charge of personnel affairs and the manager in charge of kitchen need to realize the importance of empowerment and especially have an much interest in all parts including self determination, influence power and role performance ability and personal relations ability etc.

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A Study on the Hydraulic Pump/Motor Control in the Flywheel Hybrid Vehicle

  • Oh, Boem-Sueng;Ahn, Kyoung-Kwan;Cho, Yong-Rae
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.307-311
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    • 2004
  • In this study, a novel hybrid vehicle is proposed. The vehicle has a flywheel-engine hybrid system. Flywheels are more effective as energy charge systems than electric batteries in a respect of output power density. However, transmissions to effectively drive flywheels are very complex systems such as CVTs (Continuously Variable Transmissions). In the proposed hybrid vehicle, Constant Pressure System is employed, which is hydraulic power transmission. Using Constant Pressure Systems, hydraulic CVTs are easily realized with variable displacement pumps/motors. In this paper, firstly, the proposed flywheel hybrid vehicle making use of Constant Pressure System is described. Secondly, fuel consumption characteristics of the flywheel hybrid vehicle are experimentally examined with the stationary test facility, which employs a flywheel as a load emulating vehicle inertia. Finally, the experimental results and discussions are described. Fuel consumption of 26km/L is expected for 10 mode driving schedule with vehicle mass of 1500kg.

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