• Title/Summary/Keyword: ThreeStep Process

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Experimental and Numerical Study of the Thermal Decomposition of an Epoxy-based Intumescent Coating (실험과 계산을 통한 에폭시 계열 내화도료의 열분해에 관한 연구)

  • Kim, Yangkyun
    • Fire Science and Engineering
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    • v.30 no.1
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    • pp.31-36
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    • 2016
  • This study investigates the characteristics of thermal decomposition of an epoxy-based intumescent paint using thermogravimetric analysis (TGA) and numerical simulation. A mathematical and numerical model is introduced to describe mass loss profiles of the epoxy-based intumescent coating induced by the thermal decomposition process. The decomposition scheme covers a range of complexity by employing simplified 4-step sequential reactions to describe the simultaneous thermal decomposition processes. The reaction rates are expressed by the Arrhenius law, and reaction parameters are optimized to fit the degradation behavior seen during thermogravimetric (TG) experiments. The experimental results show a major 2-step degradation under nitrogen and a 3-step degradation in an air environment. The experiment also shows that oxygen takes part in the stabilization of the intumescent coating between 200 and $500^{\circ}C$. The simulation results show that the proposed model effectively predicts the experimental mass loss as a function of time except for temperatures above $800^{\circ}C$, which were intentionally not included in the model. The maximum error in the simulation was less than 3%.

A Performance Evaluation of the CCA Adaptive Equalization Algorithm by Step Size (스텝 크기에 의한 CCA 적응 등화 알고리즘의 성능 평가)

  • Lim, Seung-Gag
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.3
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    • pp.67-72
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    • 2019
  • This paper evaluates the performance of CCA (Compact Constellation Algorithm) adaptive equalization algorithm by varying the step size for minimization of the distortion effect in the communication channel. The CCA combines the conventional DDA and RCA algorithm, it uses the constant modulus of the transmission signal and the considering the output of decision device by the power of compact slice weighting value in order to improving the initial convergence characteristics and the equalization noise by misadjustment in the steady state. In this process, the compact slice weight values were fixed, and the performance of CCA adaptive equalization algorithm was evaluated by the varing the three values of step size for adaptation. As a result of computer simulation, it shows that the smaller step size gives slow convergence speed, but gives excellent performance after at steady state. Especially in SER performance, the small step size gives more robustness that large values.

A Discussion of the Family-Friendly Village Model and Important Factors (가족친화마을만들기를 위한 모델 및 핵심 요소)

  • Cha, Sung-Lan
    • Journal of Families and Better Life
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    • v.28 no.2
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    • pp.63-76
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    • 2010
  • A law facilitating a family-friendly social environment was legislated in December 2007. According to the law, projects for facilitating a family-friendly social environment consisted of a family-friendly working environment, a community environment, and the promotion of a family-friendly culture. There has been much progress in developing a family-friendly working environment through projects such as those advocating for flexible work hours, an employee support system, and child care and a family care support system. However, in terms of a family-friendly community environment project, there was no noticeable advancement. Hence, this study was conducted to find ways to vitalize the family-friendly village project in terms of the family-friendly community environment project. The major findings of this study were as follows: A family-friendly village could be structured on the three axes of time, space, and relation. The model of the family-friendly village project consists of the following three steps: motivation, systematization, and participating & practicing. In the motivation step, integration, community, and sustainability were needed as basic ideologies for a family-friendly village. In the systematization step, providing systematic educational systems for residents taking on leadership and activist roles was stressed. In the participating & practicing step, many ways to facilitate residents' social relationships were suggested: starting the project from matters of common interests, making the resolution of families' problems a communal task of the residents, accepting the opinions of various groups associated with the matter, and taking a differentiated project process according to the geographic, socio-economic, and demographic characteristics of the groups. It is strongly suggested that the family-friendly village should be taken as a common functional scheme in everyone of eight livable village models because a key factor in a family-friendly village, family care, serves an essential function in any livable village model.

A Study on Participation of Consultant in Curtain Wall Construction (커튼월 공사에서의 단계별 컨설턴트 참여방안 연구)

  • Yoon Hyung-Soo;Yi Dong-Seob;Koo Cho-Jin;Hyun Chang-Tack
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.618-621
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    • 2003
  • The purpose of this study was to propose the participation of consultant pertinent to ground situations. The careful consideration of participating consultant reduces life cycle cost. duration and improves quality. The first step is studying Curtain-wall construction process by researching the documents, and Second step is analyzing Curtain-wall construction's problem through having a interview with a concerned experts (Architect, Gene-con, Sub-con. Consultant). Then we study how consultant solves the problem, propose the way of participation of consultant. The way of participation consist of three phases. the first one is to participate in design & construction process and the second one is to participate in design process, the third one is to participate in construction process. These participations are decided by evaluating project, design phase. construction phase. The verification of these participating strategies was implemented by the interview with the experts.

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Synthesis and Electromagnetic Wave Absorbing Property of BaTiO3@Fe Nanofibers with Core-Shell Structure (코어-쉘 구조를 갖는 BaTiO3@Fe 나노섬유의 합성 및 전자파 흡수 특성)

  • Lee, Young-In;Jang, Dae-Hwan;Sung, Ki-Hoon;Lee, Kyuman;Choa, Yong-Ho
    • Journal of Powder Materials
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    • v.23 no.1
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    • pp.38-42
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    • 2016
  • $BaTiO_3$-coated Fe nanofibers are synthesized via a three-step process. ${\alpha}-Fe_2O_3$ nanofibers with an average diameter of approximately 200 nm are first prepared using an electrospinning process followed by a calcination step. The $BaTiO_3$ coating layer on the nanofiber is formed by a sol-gel process, and a thermal reduction process is then applied to the core-shell nanofiber to selectively reduce the ${\alpha}-Fe_2O_3$ to Fe. The thickness of the $BaTiO_3$ shell is controlled by varying the reaction time. To evaluate the electromagnetic (EM) wave-absorbing abilities of the $BaTiO_3@Fe$ nanofiber, epoxy-based composites containing the nanofibers are fabricated. The composites show excellent EM wave absorption properties where the power loss increases to the high frequency region without any degradation. Our results demonstrate that the $BaTiO_3@Fe$ nanofibers obtained in this work are attractive candidates for electromagnetic wave absorption applications.

Automatic Generation of GCP Chips from High Resolution Images using SUSAN Algorithms

  • Um Yong-Jo;Kim Moon-Gyu;Kim Taejung;Cho Seong-Ik
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.220-223
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    • 2004
  • Automatic image registration is an essential element of remote sensing because remote sensing system generates enormous amount of data, which are multiple observations of the same features at different times and by different sensor. The general process of automatic image registration includes three steps: 1) The extraction of features to be used in the matching process, 2) the feature matching strategy and accurate matching process, 3) the resampling of the data based on the correspondence computed from matched feature. For step 2) and 3), we have developed an algorithms for automated registration of satellite images with RANSAC(Random Sample Consensus) in success. However, for step 1), There still remains human operation to generate GCP Chips, which is time consuming, laborious and expensive process. The main idea of this research is that we are able to automatically generate GCP chips with comer detection algorithms without GPS survey and human interventions if we have systematic corrected satellite image within adaptable positional accuracy. In this research, we use SUSAN(Smallest Univalue Segment Assimilating Nucleus) algorithm in order to detect the comer. SUSAN algorithm is known as the best robust algorithms for comer detection in the field of compute vision. However, there are so many comers in high-resolution images so that we need to reduce the comer points from SUSAN algorithms to overcome redundancy. In experiment, we automatically generate GCP chips from IKONOS images with geo level using SUSAN algorithms. Then we extract reference coordinate from IKONOS images and DEM data and filter the comer points using texture analysis. At last, we apply automatically collected GCP chips by proposed method and the GCP by operator to in-house automatic precision correction algorithms. The compared result will be presented to show the GCP quality.

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Microbiological Hazard Analysis for Seasoned Sweet Potato Stems in a Free Meal service Operation for the Elderly in Sungnam (성남시 무료 노인 급식에서 제공되는 고구마줄기무침의 미생물학적 위해 분석)

  • Park, Ji-Hyun;Kim, Hae-Young
    • Korean journal of food and cookery science
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    • v.23 no.3 s.99
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    • pp.378-387
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    • 2007
  • In this study, we investigated the application of HACCP for a prepared side dish of sweet potato stems, within a free meal service system for the elderly in the Sungnam area. Total bacterial counts (TBC) and levels of coliforms and Esherichia coli (E.coli) were analyzed through an eight step cooking process. The TBCs of the raw samples ranged between 3.30 and 1.37${\times}10^4$ CFU/g per 100 cm$^2$ The trimmed, blanched, and drained sweet potato stems showed a mean TBC value of 1.37${\times}10^4$ CFU/g, and the level of coliforms was 1.48${\times}10^3$ CFU/g. Among the eight samples, however, after stir-frying and serving, the TBC decreased to a standard satisfactory level, and a coliforms and E. coli were not found. A five step process was used and samples were taken to check the microbial quality of the cook and cooking equipment. Here we tested for TBC, coliforms, Staphylococcus aureus (S. aureus), and Salmonella. Specifically, the TBC and number of coliforms were examined on the cook's hand's, cutting board, and knife, as they represented hazards for cross-contamination. The three inspection steps of preparation of the trimmed, rinsed, blanched, and drained sweet potato stems, cook's' hands, cutting board and knife were all considered CCPs, and a manual of cooking process management was established to improve the risk factors in this study. In conclusion, this study reinforces that microbiological analysis is as a valuable tool for checking what points and stages of the cooking process must be controlled.

A Proactive Inference Method of Suspicious Domains (선제 대응을 위한 의심 도메인 추론 방안)

  • Kang, Byeongho;YANG, JISU;So, Jaehyun;Kim, Czang Yeob
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.26 no.2
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    • pp.405-413
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    • 2016
  • In this paper, we propose a proactive inference method of finding suspicious domains. Our method detects potential malicious domains from the seed domain information extracted from the TLD Zone files and WHOIS information. The inference process follows the three steps: searching the candidate domains, machine learning, and generating a suspicious domain pool. In the first step, we search the TLD Zone files and build a candidate domain set which has the same name server information with the seed domain. The next step clusters the candidate domains by the similarity of the WHOIS information. The final step in the inference process finds the seed domain's cluster, and make the cluster as a suspicious domain set. In experiments, we used .COM and .NET TLD Zone files, and tested 10 seed domains selected by our analysts. The experimental results show that our proposed method finds 55 suspicious domains and 52 true positives. F1 scores 0.91, and precision is 0.95 We hope our proposal will contribute to the further proactive malicious domain blacklisting research.

Facial Shape Recognition Using Self Organized Feature Map(SOFM)

  • Kim, Seung-Jae;Lee, Jung-Jae
    • International journal of advanced smart convergence
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    • v.8 no.4
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    • pp.104-112
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    • 2019
  • This study proposed a robust detection algorithm. It detects face more stably with respect to changes in light and rotation forthe identification of a face shape. The proposed algorithm uses face shape asinput information in a single camera environment and divides only face area through preprocessing process. However, it is not easy to accurately recognize the face area that is sensitive to lighting changes and has a large degree of freedom, and the error range is large. In this paper, we separated the background and face area using the brightness difference of the two images to increase the recognition rate. The brightness difference between the two images means the difference between the images taken under the bright light and the images taken under the dark light. After separating only the face region, the face shape is recognized by using the self-organization feature map (SOFM) algorithm. SOFM first selects the first top neuron through the learning process. Second, the highest neuron is renewed by competing again between the highest neuron and neighboring neurons through the competition process. Third, the final top neuron is selected by repeating the learning process and the competition process. In addition, the competition will go through a three-step learning process to ensure that the top neurons are updated well among neurons. By using these SOFM neural network algorithms, we intend to implement a stable and robust real-time face shape recognition system in face shape recognition.

A Study on the Post-purchase Satisfaction of Clothing related to Clothing Type and Sex (의류제품유형 및 성별에 따른 구매후 만족에 관한 연구)

  • 김지영;박재옥
    • The Research Journal of the Costume Culture
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    • v.10 no.1
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    • pp.49-59
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    • 2002
  • The type of product and consumer characteristis have known to play an important role in the post-purchase behavior. The issue related to the effects of clothing type and sex on the process of consumer satisfaction formation, would be helpful to understand the past-purchase consumer behavior. Therefore, the objective of this study was to clarify differences in the process of satisfaction formation in relation to clothing type and sex. The study was conducted in three steps. Through the two steps, measurement instruments were developed. At the last step, judgement sampling method was utilized to collect the data and subjects were 614 university students. Factor analysis and path analysis were used to analyze the data. The process of consumer satisfaction formation in formal wear and casual wear showed some differences. In the case of format wear, only expressive product performance was found to play an important role in the process of consumer satisfaction formation. However in the case of casual wear, both expressive and instrumental product performances had influence upon clothing satisfaction directly or through consumption emotion. The results revealed a similar tendency in the process of satisfaction formation between male and female groups. However in the male group the consumption emotion had a greater effect on the process of consumer satisfaction formation than in the female group it did.

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