• Korean Journal of Optics and Photonics
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• v.19 no.4
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• pp.294-301
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• 2008

We have performed modeling and simulations of optical characteristics for a cholesteric liquid crystal (CLC) color filter. Berreman's $4{\times}4$ matrix method was used for the calculation of reflectance spectra of the CLC color filter with respect to the incident angle. The results were employed as input parameters for a user-defined coating property of an illumination design software based on the ray-tracing method, LightTools. Color shift characteristics of a planar transmission-type CLC color filter were simulated using LightTools. The results were compared with the results obtained with Berreman's $4{\times}4$ matrix method. It was found that color shift characteristics of the CLC color filter could be simulated to a reasonable accuracy when the reflectance spectra with less than 5 degrees of incremental incidence-angle were used as the input data for the user-defined coating property of LightTools. We have simulated color shift characteristics of a reflection-type CLC color filter having hemi-spherical patterns. The simulation method reported in this paper has been found to be also used for a non-planar CLC color filter structure.

• Journal of the Korea Society of Computer and Information
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• v.29 no.1
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• pp.21-30
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• 2024

In this paper, we propose a method to build a sample dataset of the features of eight sensor-only facilities built as infrastructure for autonomous cooperative driving. The feature extracted from point cloud data acquired by LiDAR and build them into the sample dataset for recognizing the facilities. In order to build the dataset, eight sensor-only facilities with high-brightness reflector sheets and a sensor acquisition system were developed. To extract the features of facilities located within a certain measurement distance from the acquired point cloud data, a cylindrical projection method was applied to the extracted points after applying DBSCAN method for points and then a modified OTSU method for reflected intensity. Coordinates of 3D points, projected coordinates of 2D, and reflection intensity were set as the features of the facility, and the dataset was built along with labels. In order to check the effectiveness of the facility dataset built based on LiDAR data, a common CNN model was selected and tested after training, showing an accuracy of about 90% or more, confirming the possibility of facility recognition. Through continuous experiments, we will improve the feature extraction algorithm for building the proposed dataset and improve its performance, and develop a dedicated model for recognizing sensor-only facilities for autonomous cooperative driving.

• The KIPS Transactions:PartC
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• v.10C no.2
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• pp.125-132
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• 2003

In the paper, we can select the best safeguard as proposed the definite and systematical method and procedure on risk mitigation of risk management for information system. The practical risk mitigation methodology has a good fulfillment procedure and a definition to fulfill procedure on each phase. So, it is easy to fulfill and can apply to any risk management methodology. The practical risk mitigation is composed of 6 phases, which are the existing safeguard assessment, safeguard means selection, safeguard technique selection, risk admission assessment, cost-effective analysis and safeguard embodiment. The practical risk mitigation's advantages are as follow. Efficient selection of safeguards to apply to risk's features with safeguard's means and techniques before embodying safeguards. Prevention of redundant works and security budgets waste as re-using the existing excellent safeguards through the existing safeguard assessment. Reflection of organization's CEO opinions to require special safeguards for the most important information system.

• Journal of Digital Convergence
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• v.11 no.8
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• pp.191-197
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• 2013

In this paper, we implemented a paper currency recognition system using IR(infrared) sensor. The system has 32 channel IR sensor to measure the reflection and penetration quantity of light. The IR image of paper currency of 10-bit gray scale is used to differentiate the real and counterfeit paper currency with image information from 0 to 4095. The characteristics of IR image are recognized by brightness and darkness and the positions of bright and dark portions are different between real and counterfeit paper currency. The price of IR sensors were relatively high, however, it is good price in these days due to mass production to apply to counterfeit detection area. We used a software table having the IR characteristics of real paper currency to compare with the IR images of the input paper currency. The performance of the implemented system shows 1-2% error rates for Euro real paper currency and 0% error rates for various counterfeit paper currencies of several countries.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.12
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• pp.1148-1154
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• 2011

In this paper, the radiation properties of a Ka-band Von Karman radome are analyzed by using an IPO(Iterative PO) scheme. Since the operating frequency is very high, and the size of the considered radome is large, a numerical method cannot be directly applied to calculate the properties of the radome such as transmission loss, radome pattern, boresight error, etc. Hence, in this paper, an IPO scheme is used, which can efficiently consider the multiple interaction inside the radome. Also, the IPO scheme is based on the PO scheme, which is efficient and fast in a numerical point of view. The proposed scheme is verified based on Ku-band measurement data, and its feasibility for applicability to a higher frequency simulation is addressed through a simulation at the Ka-band.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.227-227
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• 2012

본 연구에서는 RF스퍼터링법에 의하여 glass substrate에 In-Zn-Sn-O (IZTO)를 Zn 성분에 변화를 주면서 $350{\AA}$ 만큼 증착시키고, 1시간 동안 $350^{\circ}C$로 열처리 하였다. In:Zn:Sn의 성분 비율은 20:48:32 (IZTO1), 13:60:27 (IZTO2)이다. 박막의 전자적, 광학적 특성은 XPS (X-ray Photoelectron Spectroscopy), REELS(Reflection Electron Energy Loss Spectroscopy), UV-Spectrometer를 이용하여 연구하였고, 박막의 전기적 특성은 van der Pauw 법을 이용하여 측정하였다. XPS측정결과, IZTO박막은 In-O, Sn-O and Zn-O의 결합을 가진다. REELS를 이용해 Ep=1,500 eV에서의 밴드갭을 얻어보면, $350^{\circ}C$로 열처리 한 박막은 열처리를 하지 않은 것에 비해 밴드갭이 IZTO1는 3.36 eV에서 3.54 eV로, IZTO2는 3.15 eV에서 3.31 eV로 증가하였다. 반면에 Zn 함량이 증가할수록 밴드갭이 감소하는 것을 확인할 수 있었다. 이 값은 UV-Spectrometer를 이용한 광학적 밴드갭과 일치하였다. 또한 van der Pauw method를 이용한 전기적 특성 분석 결과, 열처리를 하기 전에 비하여 carrier concentration이 IZTO1는 $-4.4822{\times}10^{18}cm^{-3}$에서 $-2.714{\times}10^{19}cm^{-3}$로, IZTO2는 $-3.6931{\times}10^{17}cm^{-3}$에서 $-1.7679{\times}10^{19}cm^{-3}$로 증가하였다. 반면에 Resistivity는 IZTO1의 경우 $1.7122{\times}10^{-1}{\Omega}{\cdot}cm$에서 $5.5496{\times}10^{-3}{\Omega}{\cdot}cm$로, IZTO2는 $1.3290 {\Omega}{\cdot}cm$에서 $1.3395{\times}10^{-2}{\Omega}{\cdot}cm$로 감소하였다. 그리고 UV-Spectrometer를 이용한 광학적 특성을 측정해본 결과, 가시광선영역인 380~780 nm에서의 투과율이 83%이상으로 투명전자소자로의 응용이 가능하다는 것을 보여주었다.

• Journal of Korean Academy of Nursing
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• v.29 no.2
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• pp.293-303
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• 1999

The purpose of this study was to understand and to explain how were nursing students experienced and accepted the fundemental nursing practice. In addition to, the results of this study are attempted to contribute for offer of basic data in projecting and accomplishing to promote quality practice education. The participants were 79 freshmen of S College of Nursing in kyungi-do. They presented record of feeling and thinking on their the fundemental nursing practice experience. The data were collected from 29, J une to 10, July in 1998. Collected data was analyzed by means of Van Kaam's phenomenological method. The results of this study was founded 423 descriptive expression and they were grouped under 42 common factors and they were grouped under 9 categories. By means of the frequency on the categories. the higher category is Anxiety. next Solemn. Flutter. Pride. Usefulness, Recognition of reality in nursing-system. Lack of practice environment. Self-accusation. Comprehension of nursing spirit were founded. 5 common factors. Tension. Difficulty, Dread. Apprehension, Burden were grouped under Anxiety. 7 common factors, Pledge, Memory, Importance of practice, Sincerity, Restriction of dress, Acceptance, Active attitude were grouped under solemn. 5 common factors, Interest, Strange, Beanimated, Waiting, Curiosity were grouped under Flutter. 5 common factors, Conceit, Self-confidence, Skilled, Worth, Accomplishment were grouped under Pride. 6 common factors, Acknowledge of nursing affairs, Expectation of furture, Fascination of nursing. Acquirement of disposition of nurse, Association of injection, Actual feeling of dept. of nursing were grouped under Recognition of reality in nursing-system. 4 common factors, Lack of practice time, Many persons of practice, Lack of practice instrument, Lack of reality were grouped under Lack of practice envirnment. 5 common factors, Inconvenient, Reflection, Loss of pride, Shyness, Feeling sorry were grouped under Self-accusation. 3 common factors, Utility, Connection of practice and theory, Various experience were grouped under Usefulness. 2 common factors, Comprehension on the dignity of human, Comprehension on a point of view of patient were grouped under Comprehension of nursing spirit. In conclusion, the following recommendation should be necessary a supplementary study to approach on the type of students that has a firm view and care about client prior to clinical nursing practice.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.288-293
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• 2008

The standard prestressed concrete I-girder bridge (PSC I-girder bridge) is one of the most prevalent types for small and medium bridges in Korea. When determining the member forces in a section to assess the safety of girder in this type of bridge, the general practice is to use the simplified practical equations or the live load distribution factors proposed in design standards rather than the precise analysis through the finite element method or so. Meanwhile, the live load distribution factors currently used in Korean design practice are just a reflection of overseas research results or design standards without alterations. Therefore, it is necessary to develop an equation of the live load distribution factors fit for the design conditions of Korea, considering the standardized section of standard PSC I-girder bridges and the design strength of concrete. In this study, to develop an equation of the live load distribution factors, a parametric analysis and sensitivity analysis were carried out on the parameters such as width of bridge, span length, girder spacing, width of traffic lane, etc. Then, an equation of live load distribution factors was developed through the multiple linear regression analysis on the results of parametric analysis. When the actual practice engineers design a bridge with the equation of live load distribution factors developed here, they will determine the design of member forces ensuring the appropriate safety rate more easily. Moreover, in the preliminary design, this model is expected to save much time for the repetitive design to improve the structural efficiency of PSC I-girder bridges.

• Journal of architectural history
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• v.20 no.6
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• pp.57-76
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• 2011

This study is on the pedagogical convention of architectural history in Korea, especially that of Western Architecture. Recent institutional change in architectural school in Korea has caused overall restructuring of academic program. In spite of extension in the field of history there was no progress of method and way of thinking. There is no change in the point of view to see the western architecture and its history as a unique and specialized phenomenon in the civilization of mankind. Because of no recognition about for what, for whom, and how to, and because of orientalism, the cultural position of western architectural history and its narrative was not asked. With the help of post-colonialism, de-constructivism and critical historiography this paper tries to show the fundamental premise of western architectural history as a myth and show its prejudice as not being justifiable. The background of the discourse there has been a representation effect with regard to knowledge as a power. we need to escape from this kind of cognitional frame With the analysis of the its premise and narrative we can find it is a historical construct that was made in the age of imperialism. In fact it has a lot of false information and problematic point of view. The Identity and originality of western architecture and its history has no logical reason or foundation if we think that it depends on the difference and comparison with other civilization. For example the explanation of its historical origin western architecture has big difference with Islamic architecture in spite of the resemblance each other. This paper try to show several reasons that discourse of western architectural history can not be survived any longer. So we need to reconstruct new pedagogy with deconstruction for the students of non western, or Korean students. Because it has important effect to see and think about architecture and its history.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.6
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• pp.1049-1056
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• 2016

In this paper, a design method for a compact dual-band slot antenna with bent slot is studied. Bent slots are added on the rectangular slot of the proposed antenna for dual-band operation. The rectangular slot is fed by a coaxial cable by placing a rectangular feeding patch inside the slot. When the bent slots are added onto the both corner of the upper side of the rectangular slot symmetrically, a new resonant frequency is created in low frequency because of the increasement of the slot length. A prototype of the proposed dual-band slot antenna operating at 2.45 GHz WLAN band and 4.50-8.30 GHz band including 5GHz WLAN band is fabricated on an FR4 substrate with a dimension of 30 mm by 30 mm. Experiment results show that the antenna has a desired impedance characteristic with a frequency band of 2.40-2.49 GHz and 4.33-9.85 GHz for an input reflection coefficient < -10 dB.