• International Journal of Precision Engineering and Manufacturing
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• 제8권2호
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• pp.70-74
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• 2007

This paper describes the development of a nano-positioning system for nanoscale science and engineering. Conventional positioning systems, which can be expensive and complicated, require the use of laser interferometers or capacitive transducers to measure nanoscale displacements of the stage. In this study, a new self-displacement sensing (SDS) nano-stage was developed using mechanical magnification of its displacement signal. The SDS nano-stage measured the displacement of its movement using a position-sensitive photodiode (PSPD), a laser source, and a hinge-connected rotating mirror plate. A beam from a laser diode was focused onto the middle of the plate with the rotating mirror. The position variation of the reflected beam from the mirror rotation was then monitored by the PSPD. Finally, the PSPD measured the amplified displacement as opposed to the actual movement of the stage via an optical lever mechanism, providing the ability to more precisely control the nanoscale stage. The displacement amplification process was modeled by structural analysis. The simulation results of the amplification ratio showed that the distance variation between the PSPD and the mirror plate as well as the length L of the mirror plate could be used as the basic design parameters for a SDS nano-stage. The PSPD was originally designed for a total travel range of 30 to 60 mm, and the SDS nano-stage amplified that range by a factor of 15 to 25. Based on these results, a SDS nano-stage was fabricated using principle of displacement amplification.

• 한국지구과학회지
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• 제35권5호
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• pp.324-332
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• 2014

Many problems in naming natural monuments have been repeatedly argued by many researchers, and four different types of naming problems were identified: 1) name of unknown nationality (natural monument no. 82 and 108), 2) morphological name rather than scientific name (natural monument no. 180, 295, and 409), 3) name of fable character (local cultural property of Changnyeonggun), and 4) scientifically wrong name (natural monument no. 413). Among them, two cases (case 3 and 4) using wrong names are found in natural monument of geologic heritages, which should be ascribable to a hasty designation without an accurate and thorough scientific research. In order to solve these problems and to establish an ideal policy in designating natural monument, National Research Institute of Cultural Heritage has been carrying out a research project of "Pre-study and Post-designation (PSPD)", especially targeting the rod-shaped stromatolite. It is likely that this new strategy of PSPD is a unique and the first step to solve many problems in designating and naming geologic heritages as natural monuments. As a consequence, we strongly suggest that PSPD system must be applied to natural monument designation as an institutional arrangement.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2287-2290
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• 2003

In this paper, an image vector quantization method is proposed not only to improve the compression ratio but also to reduce the computation cost. The proposed method could save the computation cost of codebook generation and encoding by using the modified LBG algorithm of Partial Search Partial Distortion (PSPD) in wavelet domain, by which the code book was constructed together with the partial codebook search, the partial code vector elements, and the interruption criterion. We have designed and implemented the vector quantizer to verify the improvement in reducing compression ratio in encoding processing and reducing the computation cost.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.36-36
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• 2002

To Establish of standard technique of length measurent in 2D plane, we develope AFM system. The XY scanner scans the sample only in XY plane, while the Z scanner scans the specimen only in Z-direction. Cantilever tip is controlled to has constant height relative to speciman surface by feedback of PSPD signal. To acquire high accuracy, Z-axis measuring sensor will be added.(COXI or others). In this paper we design XYZ stage suitable for this AEM system. For XY stage, single module parallel-kinnematic flexure stage is used which has high orthogonality and minimum out-of-plane motion. To obtain best performance optimal design is performed. For XY stage, to be robust about parasitic motion optimal design of maximizing Z and tilt stiffness is performed under the constraint of motion range and stage size. And for Z stage, optimal design of maximizing 1st resonant frequency is performed. Because if resonant frequency is get higher, scan speed is improved. So it makes reduce the error by sensor drift. Resultly XYZ stage each have 1st natural frequency of 115㎐, 201㎐, 2.66㎑ and range 109㎛, 110㎛, 12㎛.

• 한국사회복지학
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• 제49권
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• pp.264-295
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• 2002

This study aims to identify the enactment factors of the National Basic Livelihood Institution in context of policy making process by using Kingdon's policy Stream Model. The findings of this study can be summarized as follows. First, an economic crisis has worsened social problems, and the president Kim Dae-jung recognized these problems as serious and worried about social confusion and polarization. Second, NGOs as like People's Solidarity for Participatory Democracy put efforts into enacting the Act. Also, the president Kim's government faced a series of political crisis and needed political solution including foundation of a new party, which considered social welfare most important. Third, the PSPD designed the Act. But the alternatives of related government ministries were not selected. In conclusion, the National Basic Livelihood Institution was enacted by the combination of these three factors stream. Especially the political stream was strongest.

• Restorative Dentistry and Endodontics
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• 제26권2호
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• pp.134-140
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• 2001

The polymerization shrinkage of composite resins is an important drawback although the composites have many advantages-more esthetic and conservative than metallic restoratives etc. The purposes of this research were to develop a new measurement method and to manufacture an instrument that can measure the initial dynamic volumetric shrinkage of composite resins during polymerization. The instrument was basically an electromagnetic balance that constructed with a force transducer using position sensitive photo detector(PSPD) and a negative feedback servo amplifier of proportional-derivative(PD) controller. The volumetric change of composites during polymerization was detected continuously as buoyancy change in distilled water by means of Archimedes's principle. It was converted to continuous electrical voltage signal in real time. The signal was properly conditioned and filtered and then it was stored in computer by a data acquisition(DAQ) board. By using this electronic instrument. the dynamic patterns of the polymerization shrinkage of eight commercial(Z-100, DenFil, AeliteFil, Z-250, P-60, SureFil, Synergy compact, and Tetric ceram) composite resins were measured and compared. The results were as follows. 1. From this project of developing instrument, the ability has been achieved that can acquire and process data of electrical signal transformed from various physical phenomenon by using temperature, displacement. photo. and force transducer. As a consequence, the instrumentation and measurement system used to analyze the physical characteristics of various dental materials in dental research field can be designed, manufactured and implemented in lab. 2. This instrument has some advantages. It was insensible to temperature change and could measure true dynamic volumetric shrinkage in real time without complicated process. It showed accuracy and high precision results with small standard deviation. 3. The polymerization shrinkage of composites was significantly different between brands and ranged from 2.47％ to 3.89％, The order of polymerization shrinkage was as follows, in order of increasing shrinkage, SureFil, P60, Z250, Z100, Synergy compact. DenFil, Tetric ceram, and AeliteFil. 4. The polymerization shrinkage rate per unit time, dVol％/dt, showed that the instrument can provide an indirect research method for polymerization reaction kinetics.

• 기록학연구
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• 제22호
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• pp.37-76
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• 2009

이 논문은 한국의 정보공개운동의 역사적 전개 과정과 현재적 쟁점, 새로운 전환의 성격을 정치과정론에 입각한 단체 간 비교연구를 통해 분석하는 것을 목적으로 한다. 1998년 정보공개법의 시행을 전후하여 본격적으로 시작된 한국의 정보공개운동은, 이후 10여 년 동안 '확장'과 '확산'(1999년~2004년), '제도화'와 '탈제도화'(2005년~2008년)의 시기를 거쳐 전개되어 왔다. 특히 1998년 설립된 참여 연대 정보공개사업단은 정보공개제도의 개선, 관행의 혁파를 주도하며 초기 정보공개운동을 이끌었다. 그러나 역설적으로 노무현 정부에서 중요한 제도적 진전이 있은 이후, 정보공개운동의 활력이 약화되는 양상도 보였다. 정보공개제도와 관행이 후퇴하고 있는 이명박 정부에서는, 기존의 정보공개운동 주도세력들이 아닌 새로운 주체들이 등장하여 운동의 '이중적 전환'을 이끌고 있음이 확인된다. 2008년 창립한 투명사회를 위한 정보공개센터에는 법률가나 시민운동가 이외에 언론인, 기록학계, 일반 시민 등이 적극적으로 참여하고 있고, 블로그형 홈페이지를 통해 수많은 정보들이 '공개'되고 '공유'되고 있다. 다양한 시민교육 프로그램은 센터를 시민과 소통케 하고, 회원을 확보하는 쌍방향의 통로가 되고 있다. 정보공개센터는 과거 참여연대 정보공개사업단과 달리, 정책제안이나 정보공개 소송, 논평이나 성명, 토론회 개최 등의 전통적 방식과 의제들과 구분되는 운동을 펼치고 있는 것이다. 이들은 '대변형' 운동을 '역량강화형' 운동으로, 그리고 정보공개운동의 프레임을 '공개'에서 '공유'로, 정보공개운동의 '이중적 전환'을 이끌고 있다.