• 한국정보통신학회논문지
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• 제15권7호
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• pp.1552-1558
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• 2011

본 논문에서는 전압제어지연단(Voltage Controlled Delay Line : VCDL)을 이용하여 기존의 위상고정루프와 다른 형태의 위상 지연고정루프(Phase Delay Locked Loop)를 제안하였다. 이 구조를 이용하여 기존의 위상고정루프의 2차 또는 3차 루프필터(Loop Filter)를 단하나의 커패시터로 구현하여 칩의 크기를 크게 줄였다. 새로이 제안하는 듀얼루프 위상 자연고정루프에서는 전압제어지연단 경로의 커패시터와 전하펌프의 전류 크기를 조절함으로서 작은 이득 값을 가지는 전압제어지연단을 사용할 수 있다. 제안된 회로는 $0.18{\mu}m$ CMOS 공정의 파라미터를 이용하여 Hspice로 시뮬레이션을 수행하고 회로의 동작을 검증하였다.

• 한국광학회지
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• 제8권2호
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• pp.161-164
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• 1997

편광유지 광섬유를 이용한 주파수가 안정화된, 두 개의 서로 수직으로 편광된 종모우드를 갖는 He-Ne레이저 빛을 LoTa $O_{3}$ 위상변조기로 구성된 센서부(sensor head)로 전달해 줌으로써 원격에서 전기장을 측정할 수 있는 hybrid, heterodyne 간섭식 센서를 구성하였다. In/quadrature-phase위상변조풀이 방식을 이용하여 전기광학 효과에 의해 서로 수직으로 편광된 두 모우드 사이에 유도된 위상차이를 측정함으로써 항상 높은 검지율을 유지할 수 있는 전기장 센서를 구성하고, 이를 이용하여 광학 물질에 유도된 복굴절도 측정을 할 수 있었다.

• Journal of Welding and Joining
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• 제11권2호
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• pp.42-52
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• 1993

The corrosion fatigue fracture behaviour of dual phase steel was investigated in 3% NaCl solution at 302MPa and 137MPa. Fatigue test was conducted by cantilever type of self-made rotary bending fatigue testing machine. The fatigue strength increased with increasing the hardness of 2nd phase. Corrosion pit originated at the boundary of the 2nd phase. The size and number of corrosion pits were influenced by the 2nd phase hardness, and pits remained constant in size just after they were transited into cracks. The life of crack initiation was effected by stress level. The shape of relation of .DELTA. K and da/dN has smaller scattering in it in 3% NaCl solution than that in air. The higher the 2nd phase hardness is, the greater the corrosion fatigue life becomes. Corrosion fatigue fracture behaviour was primarily effected by mechanical factor in case of high stress(302MPa), but by electro-chemical reaction in a lower stress(137MPa). As stress level got lower and hardness of the 2nd phase got higher, the roughness of fracture surface increased.

• 대한기계학회논문집
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• 제7권4호
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• pp.398-403
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• 1983

In this investigation, the effect of microstructural factors on the impact energy was studied, using dual phase steels with soft phase of ferrite encapsulated by hard phase of martensite. It was found that the effect of the ferrite grain size on the impact energy decreases as the strength ratio increases, these results are due to the micro-brittlefracture facet by the difficulty of cleavage crack formation in the ferrite grain.

• 오토저널
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• 제9권3호
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• pp.76-84
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• 1987

A study has been made to clarify the microstructural effect on static tensile properties of the dual phase steel, in which the martensitic phase encapsulated islands of ferritic phase. The main results are as follows: Yield strength is associated with the degree of plastic constraint factor and tensile strength increases with increasing of strain hardening exponent. Also, the variation of ductility is dependent upon the amount of micro-brittle facets.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.271-274
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• 1999

This paper proposes a simple architecture of digital dividing block in dual-modulus prescaler phase-locked loop used in the wireless communication. Proposed architecture eliminates a swallow counter in the conventional one and demonstrates the advantages in reducing the power consumption and the gate-counts. Therefore, it is suitable for small die area and low power applications. The circuit is designed in a standard 0.35${\mu}{\textrm}{m}$ CMOS process.

• Coupled systems mechanics
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• 제9권5호
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• pp.411-432
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• 2020

This research is devoted to the study of plane wave propagation in homogeneous transversely isotropic (HTI) magneto-thermoelastic rotating medium with combined effect of Hall current and two temperature due to multi-dual-phase lag heat transfer. It is analysed that, for 2-D assumed model, three types of coupled longitudinal waves (quasi-longitudinal, quasi-transverse and quasi-thermal) are present. The wave characteristics like phase velocity, specific loss, attenuation coefficients, energy ratios, penetration depths and amplitude ratios of transmitted and reflected waves are computed numerically and illustrated graphically and compared for different theories of thermoelasticity. Some particular cases are also derived from this research.

• Corrosion Science and Technology
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• 제10권5호
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• pp.162-166
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• 2011

Effects of chemical compositions and manufacturing conditions on mechanical properties and microstructures were investigated in order to obtain galvannealed high strength dual phase steel sheets with superior mechanical properties and coating properties. An intercritical annealing between Ac1 and Ac3 was conducted to produce the DP (dual phase) steel sheets, followed by quenching to room temperature. The purposes of Al addition are to reduce the iron oxidation with chemical composition (Si, Mn etc.) and to improve the wettability by liquid zinc. The present study will focus on the characterization for making dual phase steel sheets and enhancing the galvanizability of Al added DP steel sheets about continuous annealing line in CGL.

• Journal of electromagnetic engineering and science
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• 제14권1호
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• pp.15-24
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• 2014

A compact dual-band three-way metamaterial power divider is proposed that has three in-phase outputs. Fully printed composite rightand left-handed (CRLH) unequal and equal power dividers are first implemented for 900-MHz and 2.4-GHz bands with the power-division ratios of 2:1 and 1:1, respectively. An initial 1:1:1 power divider is then achieved by incorporating the input of the two-way equal block into an output of the unequal block, and trimming the interconnection parameters. The condition of an identical phase at the three outputs of the power divider is then met by devising a hybrid CRLH phase-shift line to compensate for the different phase errors at the two frequencies. This scheme is confirmed by predicting the performance of the power divider with circuit analysis and full-wave simulation and measuring the fabricated prototype. They results show agreement; the in-phase outputs as well as the desirable power-division are accomplished and outdo the conventional techniques.

• 한국재료학회지
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• 제30권6호
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• pp.315-320
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• 2020

This study deals with the yielding behavior and strain aging properties of three bake hardening steels with dual-phase microstructure, fabricated by varying the annealing temperature. Bake hardening and aging tests are performed to examine the correlation of martensite volume fraction with yielding behavior and strain aging properties of the bake hardening steels with dual-phase microstructure. The volume fraction of martensite increases with increasing annealing temperature. Room-temperature tensile test results show that the yielding behavior changes from discontinuous-type to continuous-type with increasing volume fraction of martensite due to higher mobile dislocation density. According to the bake hardening and aging tests, the specimen with the highest fraction of martensite exhibited high bake hardening with low aging index because solute carbon atoms in ferrite and martensite effectively diffuse to dislocations during the bake hardening test, while in the aging test they diffuse at only ferrite due to lower aging temperature.