• Title/Summary/Keyword: 자기조합

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Design of 3-bit Arbitrary Logic Circuit based on Single Layer Magnetic-Tunnel-Junction Elements (단층 입력 구조의 Magnetic-Tunnel-Junction 소자를 이용한 임의의 3비트 논리회로 구현을 위한 자기논리 회로 설계)

  • Lee, Hyun-Joo;Kim, So-Jeong;Lee, Seung-Yeon;Lee, Seung-Jun;Shin, Hyung-Soon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.12
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    • pp.1-7
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    • 2008
  • Magnetic Tunneling Junction (MTJ) has been used as a nonvolatile universal storage element mainly in memory technology. However, according to several recent studies, magneto-logic using MTJ elements show much potential in substitution for the transistor-based logic device. Magneto-logic based on MTJ can maintain the data during the power-off mode, since an MTJ element can store the result data in itself. Moreover, just by changing input signals, the full logic functions can be realized. Because of its programmability, it can embody the reconfigurable magneto-logic circuit in the rigid physical architecture. In this paper, we propose a novel 3-bit arbitrary magneto-logic circuit beyond the simple combinational logic or the short sequential one. We design the 3-bit magneto-logic which has the most complexity using MTJ elements and verify its functionality. The simulation results are presented with the HSPICE macro-model of MTJ that we have developed in our previous work. This novel magneto-logic based on MTJ can realize the most complex logic function. What is more, 3-bit arbitrary logic operations can be implemented by changing gate signals of the current drivel circuit.

Statistical Approach of Measurement of Signal to Noise Ratio in According to Change Pulse Sequence on Brain MRI Meningioma and Cyst Images (뇌 수막종 및 낭종에서 자기공명영상 펄스 시퀀스 변화에 따른 신호대잡음비의 통계적 접근)

  • Lee, Eul-Kyu;Choi, Kwan-Woo;Jeong, Hoi-Woun;Jang, Seo-Goo;Kim, Ki-Won;Son, Soon-Yong;Min, Jung-Whan;Son, Jin-Hyun
    • Journal of radiological science and technology
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    • v.39 no.3
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    • pp.345-352
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    • 2016
  • The purpose of this study was to needed basis of measure MRI CAD development for signal to noise ratio (SNR) by pulse sequence analysis from region of interest (ROI) in brain magnetic resonance imaging (MRI) contrast. We examined images of brain MRI contrast enhancement of 117 patients, from January 2005 to December 2015 in a University-affiliated hospital, Seoul, Korea. Diagnosed as one of two brain diseases such as meningioma and cysts SNR for each patient's image of brain MRI were calculated by using Image J. Differences of SNR among two brain diseases were tested by SPSS Statistics21 ANOVA test for there was statistical significance (p < 0.05). We have analysis socio-demographical variables, SNR according to sequence disease, 95% confidence according to SNR of sequence and difference in a mean of SNR. Meningioma results, with the quality of distributions in the order of T1CE, T2 and T1, FLAIR. Cysts results, with the quality of distributions in the order of T2 and T1, T1CE and FLAIR. SNR of MRI sequences of the brain would be useful to classify disease. Therefore, this study will contribute to evaluate brain diseases, and be a fundamental to enhancing the accuracy of CAD development.

Analysis of Two-Dimensional Fluorescence Spectra in Biotechnological Processes by Artificial Neural Networks I - Classification of Fluorescence Spectra using Self-Organizing Maps - (인공신경망에 의한 생물공정에서 2차원 형광스펙트럼의 분석 I - 자기조직화망에 의한 형광스펙트럼의 분류 -)

  • Lee Kum-Il;Yim Yong-Sik;Kim Chun-Kwang;Lee Seung-Hyun;Chung Sang-Wook;Rhee Jong Il
    • KSBB Journal
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    • v.20 no.4
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    • pp.291-298
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    • 2005
  • Two-dimensional (2D) spectrofluorometer is often used to monitor various fermentation processes. The change in fluorescence intensities resulting from various combinations of excitation and emission wavelengths is investigated by using a spectra subtraction technique. But it has a limited capacity to classify the entire fluorescence spectra gathered during fermentations and to extract some useful information from the data. This study shows that the self-organizing map (SOM) is a useful and interpretative method for classification of the entire gamut of fluorescence spectral data and selection of some combinations of excitation and emission wavelengths, which have useful fluorometric information. Some results such as normalized weights and variances indicate that the SOM network is capable of interpreting the fermentation processes of S. cerevisiae and recombinant E. coli monitored by a 2D spectrofluorometer.

Experiencing the 3D Color Environment: Understanding User Interaction with a Virtual Reality Interface (3차원 가상 색채 환경 상에서 사용자의 감성적 인터랙션에 관한 연구)

  • Oprean, Danielle;Yoon, So-Yeon
    • Science of Emotion and Sensibility
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    • v.13 no.4
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    • pp.789-796
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    • 2010
  • The purpose of this study was to test a large screen and rear-projected virtual reality (VR) interface in color choice for environmental design. The study piloted a single three-dimensional model of a bedroom including furniture in different color combinations. Using a mouse with an $8'{\times}6'$ rear-projector screen, participants could move 360 degree motion in each room. The study used 34 college students who viewed and interacted with virtual rooms projected on a large screen, then filled out a survey. This study aimed to understand the interaction between the users and the VR interface through measurable dimensions of the interaction: interest and user perceptions of presence and emotion. Specifically, the study focused on spatial presence, topic involvement, and enjoyment. Findings should inform design researchers how empirical evidence involving environmental effects can be obtained using a VR interface and how users experience the interaction with the interface.

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An Unambiguous Correlation Function to Improve Tracking Performance for Binary Offset Carrier Signals (이진 옵셋 반송파 신호 추적 성능 향상을 위한 비모호 상관함수)

  • Woo, Sunghyuk;Chae, Keunhong;Lee, Seong Ro;Yoon, Seokho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.7
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    • pp.1433-1440
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    • 2015
  • In this paper, we propose an unambiguous correlation function to improve tracking performance for binary offset carrier (BOC) signals. Specifically, we divide a BOC sub-carrier into multiple rectangular pulses, and analyze that the BOC autocorrelation function is made up of the sum of several partial correlation functions. Then, we obtain two sub-correlation functions by combining two partial correlation functions and propose a novel unambiguous correlation function with no side-peak which can be regulated its width based on the combination of the sub-correlation functions and partial correlation functions. From numerical results, it is confirmed that the proposed correlation function provides a tracking performance improvement over the conventional correlation functions in terms of the tracking error standard deviation.

Fundamental and Shrinkage Properties of High Performance Concrete in Combined with Expansive Additive and Shrinkage Reducing Agent (팽창재와 수축저감제를 조합 사용한 고성능콘크리트의 기초물성 및 수축특성)

  • Han Cheon-Goo;Kim Sung-Wook;Koh Kyoung-Taek;Cheol Han-Min
    • Journal of the Korea Concrete Institute
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    • v.16 no.5 s.83
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    • pp.605-612
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    • 2004
  • This study investigated the fundamental properties and shrinkage properties of high performance concrete with water/binder ratio of 0, 30 and with combination of expansive additive and shrinkage reducing agent. According to the results, the fluidity of high performance concrete showed lower the using method in combination with expansive additive and shrinkage reducing agent than the separately using method of that, so the amount of superplasticizer increased when the adding ratio of expansive additive and shrinkage reducing agent increased. However the air content of concrete increased when used in combination with expansive additive and shrinkage reducing agent, so the amount of AR agent decreased. The compressive strength showed the highest at $5\%$ of expansive additive, and decreased with an increase of the amount of shrinkage reducing agent. Furthermore, in order to reduce the shrinkage of high performance concrete, it was found that the using method in combination with expansive additive and shrinkage reducing agent was more effective than separately using method of that. Therefore, it analyzed that the combination of expansive additive of $5\%$ and shrinkage reduction agent of $1\%$ was the most suitable mixture, considering to the fluidity, strength and shrinkage under the condition of this experiment.

Effect of metal oxides on the types of SiO$_2$ Phase of vitreous porcelain body (금속 산화물이 도자기 소지중 SiO$_2$상 생성에 미치는 영향)

  • 김윤주
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.4
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    • pp.658-664
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    • 1997
  • The effect of metal oxides($K_2O, MgO, CaO,Al_2O_3$, and $TiO_2$) on the kinds of pure $SiO_2$ phase, and $SiO_2$ phases in the composition of vitreous porcelain body was investigated. Also, the effect of the ratio $SiO_2$ to $Al_2O_3$ in the composition of porcelain body with stabilized of cristobalite phase was investigated. In the case of the addition of $K_2O, MgO, CaO, Al_2O_3$, and $TiO_2$ to pure $SiO_2$, the major phase was $\alpha$-cristobalite, $\alpha$-cristobalite, $\alpha$-quartz, $\alpha$-quartz and amorphous, respectively. As the ratio of $SiO_2$ to $Al_2O_3$ in the composition of porcelain body was decreased, the stabilization of cristobalite phase was promoted and only the critical value of $SiO_2/Al_2O_3$ ratio that stabilizing the cristobalite phase in it was 68.10/22.75. The addition of $K_2$O, MgO, CaO,Al_2O_3$, and $TiO_2$ to the composition of porcelain body stabilized already did not affect on the formation of $\alpha$-cristobalite phase which degraded the thermal properties of porcelain body, and suppressed the formation of a, $\beta$-cristobalite.

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Development of Hybrid Career Coaching Model and Effect Analysis (하이브리드 진로코칭 모형 개발 및 효과분석)

  • Go, Eun-Hyeon;Park, Hye-Rim;Kim, Do-Hyeon
    • The Journal of Korean Association of Computer Education
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    • v.18 no.6
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    • pp.43-51
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    • 2015
  • In this paper, we develops the hybrid career coaching model combined the face to face and the E-coaching, and applies students of childhood education for career guidance. The presented hybrid career coaching manages a profile and state information and a remote access between the coach and coachee on Internet. Then, online part of hybrid coaching deals with saving the data, and understand of the situation of the coachee if it is necessary. And face to face part of hybrid coaching have a conversation, the checking, counsel and introspection if the coach needs. Presented hybrid career coaching model has th procedure of 6 steps such like career coaching guidance, self-understanding, career decision-making, establishment of the career execution planning, execution plan and action will inspection and execution result inspection. Proposed hybrid career coaching is possible to understand coachee's current state on the career map, realize the importance of the execution strategy and maximize the efficiency and effectiveness self-regulation capacity.

괴델의 불완전성 정리:증명된 신화(神話)?

  • Hong, Seong-Gi
    • Korean Journal of Logic
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    • v.5 no.2
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    • pp.39-66
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    • 2002
  • 일반적으로 엄밀한 방법을 통하여 증명되었다고 말해지는 괴델의 불완전성 정리는 일련의 전제와 배경지식이 요구된다고 하겠다. 이들 중에서 무엇보다도 중요한 것은 정리의 증명에 사용되는 메타언어상의 수학적 참에 대한 개념이다. 일단 확인할 수 있는 것은 "증명도, 반증도 되지 않지만 참인 산수문장의 존재"라는 불완전성 정리의 내용에서 괴델이 가정하고 있는 수학적 참의 개념이 구문론적인 증명개념으로부터 완전히 독립되어야 한다는 점이다. 문제는 그가 가정하고 있는 수학적 참의 개념이 도대체 무엇이어야만 하겠는가라는 점이다. 이 논문은 이 질문과 관련하여 내용적으로 3부분으로 나누어 질 수 있다. I. 괴델의 정리의 증명에 필요한 전제들 및 표의 도움을 얻어 자세히 제시되는 증명과정의 개략도를 통해 문제의 지형도를 조감하였다. II, III. 비트겐슈타인의 괴델비판을 중심으로, "일련의 글자꼴이 산수문장이다"라는 주장의 의미에 대한 상식적 비판 및 해석에 바탕을 둔 모형이론에 대한 대안제시를 통하여 괴델의 정리를 증명하기 위해 필요한 산수적 참에 관한 전제가 결코 "확보된 것이 아니다"라는 점을 밝혔다. IV. 괴델의 정리에 대한 앞의 비판이 초수학적 전제에 대한 것이라면, 3번째 부분에서는 공리체계에서 생성 가능한 표현의 증명여부와 관련된 쌍조건문이 그 도입에 필수적인 괴델화가 갖는 임의성으로 인해 양쪽의 문장의 참, 거짓 여부가 서로 독립적으로 판단 가능하여야만 한다는 점에(외재적 관계!) 착안하여 궁극적으로 자기 자신의 증명여부를 판단하게 되는 한계상황에 도달할 경우(대각화와 관련된 표 참조) 그 독립성이 상실됨으로 인해 사실상 기능이 정지되어야만 한다는 점, 그럼에도 불구하고 이 한계상황을 간파할 경우(내재적 관계로 바뀜!)항상 순환논법을 피할 수 없다는 점을 밝혔다. 비유적으로 거울이 모든 것을 비출 수 있어도 자기 스스로를 비출 수 없다는 점과 같으며, 공리체계 내 표현의 증명여부를 그 체계내의 표현으로 판별하는 괴델의 거울 역시 스스로를 비출 수는 없다는 점을 밝혔다. 따라서 괴델문장이 산수문장에 속한다는 믿음은, 그 문장의 증명, 반증 여부도 아니고 또 그 문장의 사용에서 오는 것도 아니고, 플라톤적 수의 세계에 대한 그 어떤 직관에서 나오는 것도 아니다. 사실상 구문론적 측면을 제외하고는 그 어떤 것으로부터도 괴델문장이 산수문장이라는 근거는 없다. 그럼에도 불구하고 괴델문장을 산수문장으로 볼 경우(괴델의 정리의 증명과정이라는 마술을 통해!), 그것은 확보된 구성요소로부터 조합된 문장이 아니라 전체가 서로 분리불가능한 하나의 그림이라고 보아야한다. 이것은 비트겐슈타인이 공리를 그림이라고 본 것과 완전히 일치하는 맥락이다. 바론 그런 점에서 괴델문장은 새로운 공리로 도입된 것과 사실은 다름이 없다.

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A Study on the Effect of Reducing the Saturation Magnetization by Substituting the Non magnetic Ion in Mg Mn Ferrites (Mg-Mn훼라이트의 비자성 이온첨가에 의한 포화자화 감소효과)

  • Yu, Byeong-Du;Kim, Jong-O
    • Korean Journal of Materials Research
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    • v.4 no.1
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    • pp.117-124
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    • 1994
  • The reduction of saturation magnetization in the Mg-Mn microwave ferrites was achieved by substituting the non-magnetic A1 ion for Fe ion. It is necessary for extending the operation frequencies that there is no change in other properties of the microwave ferrites. The electrical and magnetic properties are characterized where the composition of the ferrites studied was given by the general formula $(MgO)_{1.0}(MnO)_{0.1}(Al_xFe_{1.9-x}O_{2.85}$ with x ranging from 0.1 to 0.4. The saturation magnetization and the ferromagnetic resonance linewidth was decreased by the substituting amount of $Al_2O_3$. The value of coercive field was low enough over the composition of x=O.2 and the high squareness ratio was obtained all over the amount of substitution. It is feasible to select the proper application area with the combination of various properties ; that is, low coercive field, high squareness ratio, optimum saturation magnetization and ferromagnetic resonance linewidth.

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