• Title/Summary/Keyword: Time-shifting

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Nonlinear Control using Stepwise Fuzzy Moving Sliding Surface (계단형 퍼지 이동 슬라이딩 평면을 이용한 비선형 제어)

  • 유병국;양근호
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2003.06a
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    • pp.153-156
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    • 2003
  • This short paper suggests a control strategy using a stepwise fuzzy moving sliding surface. The moving surface is a Sugeno-type fuzzy system that has the angle of state error vector and the distance from the origin in the phase plane as inputs and a first-order linear differential equation as an output. The surface initially passes arbitrary initial states and subsequently moves towards a predetermined surface via rotating or shifting. the proposed method reduces the reaching and tracking time and improves robustness. The asymptotic stability of the fuzzy sliding surface is proved. The validity of the proposed control scheme is shown in computer simulation for a second-order nonlinear system.

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A Study on the Development of Battery Energy Storage System (전지이용 전력저장장치 기술개발)

  • Hwang, Yong-Ha;Lee, Keun-Seob
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.905-907
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    • 1993
  • Demand for electricity is increasing annually. Especially, the daytime demand grawth shows higher than any other time period. So the big difference between maximum and minimum electrical demand becomes another important problem to be solved. The Battery Energy Storage System is chosen as one of the solutions among the sevral methods. The purpose of utilization of Battery Energy Storage System is to improve the daily load factor. Also, Battery Energy Storage System may be used for the load levelling or the load shifting as well as the spinning reserve. Up to now, only the pumped hydro power plant system has been operated on the commercial basis, but this system has so many constraints such as site, environmental effects, construction period, ect. Being considered current electrical power situation the development of electric storage system is in need latly. Among the various electric storage systems, Battery Energy System is chosen with the top priority because it has sevral merits to cover such as the short construction period, the demand site installation, and the food environmental characteristics.

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The Layout Plan for Maintenance of Urban Transit Vehicle (도시철도차량 유지보수체계 구축방안 연구)

  • Lee, Woo-Dong
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1177-1178
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    • 2007
  • There is a possibility of saying that the accident of urban transit vehice or deficit operation is caused by the m.aintenance. urban transit vehice where the efficiency is good though does the time passes and it becomes old anger and does not display that efficiency not only the cause of formation accident does becomes. The breakdown about under occurring before getting up an accident, appropriately shifting the parts is to a maintenance very the pending question fact which is important is a possibility of doing. From there is by an urban transit vehice, Mauntenance in reliability base grudge is a tool of confirms an improvement point and the place where it judges. From the research which it sees will present about technical development plan of Maintenance.

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Restructure Recommendation Framework for Online Learning Content using Student Feedback Analysis (온라인 학습을 위한 학생 피드백 분석 기반 콘텐츠 재구성 추천 프레임워크)

  • Choi, Ja-Ryoung;Kim, Suin;Lim, Soon-Bum
    • Journal of Korea Multimedia Society
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    • v.21 no.11
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    • pp.1353-1361
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    • 2018
  • With the availability of real-time educational data collection and analysis techniques, the education paradigm is shifting from educator-centric to data-driven lectures. However, most offline and online education frameworks collect students' feedback from question-answering data that can summarize their understanding but requires instructor's attention when students need additional help during lectures. This paper proposes a content restructure recommendation framework based on collected student feedback. We list the types of student feedback and implement a web-based framework that collects both implicit and explicit feedback for content restructuring. With a case study of four-week lectures with 50 students, we analyze the pattern of student feedback and quantitatively validate the effect of the proposed content restructuring measured by the level of student engagement.

The Iconography of Femininity in Pre-Raphaelite Painting

  • Choe, Jian
    • English & American cultural studies
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    • v.14 no.1
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    • pp.269-286
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    • 2014
  • The Pre-Raphaelite oeuvre abounds in the image of women, which indicates the impact of gender question on contemporary visual culture. The representation of women in their art tends to evince the entrenched myth of womanhood, marked by a stereotyped dichotomy in the apprehension of femininity. Yet there are a significant number of pictures which attest to the point that their iconography of womanhood cannot be fully elucidated by exploring the dichotomy alone. They falsify the dyadic model, defying the attempt to accommodate them in a clean-cut category. The curious blend of the mystical, the sensual, and the domestic that characterizes these images suggests that they are open to multiple interpretations. In sum, the Pre-Raphaelite representation of women both endorses and challenges the ideal of femininity, indicating that it was shaped by and shaped contemporary perceptions of women at a time when gender relations were shifting and the traditional institution of patriarchy revealed a sign of strain.

Real-time 3-D shape measurement system using harmonics error removed digital fringe projection (하모닉스 에러가 제거된 디지털 프린지 투영을 사용한 실시간 3차원 형태 측정시스템)

  • Park, Won-Kyu;Kim, Byoung-Jin;Koh, Kwang-Sik
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.11a
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    • pp.629-632
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    • 2010
  • 본 논문에서는 Fringe Pattern profilometry(FPP)을 이용한 높이 측정 시스템을 구현하고, R, G, B 각 컬러 채널별로 위상이 다른 파형을 인가함으로써 Phase shifting 방법을 이용한 실시간 위상 정보를 획득할 수 있게 한다. 디지털 프로젝터의 비선형성으로 인해 필연적으로 발생하는 하모닉스 성분을 근사화된 정현파를 인가함으로써 높이 정보에서 가장 큰 문제를 발생하는 2차 하모닉스 성분을 줄인다. 이렇게 구한 위상 값을 Digital Phase Loop Lock(DPLL)회로에 인가함으로써 3차원 모양 정보를 실시간으로 획득 가능하게 한다.

Motivating the Workforce in a Precarious Time: Focusing on Career Self-Help Advice in the U.S.

  • Jeongsuk Joo
    • International Journal of Advanced Culture Technology
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    • v.12 no.2
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    • pp.104-109
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    • 2024
  • In this paper, we examine American career self-help advice in the context of white-collar labor market changes in the U.S., especially how it tries to motivate and empower white-collar job seekers and how fundamentally flawed this is. In this regard, we focus on What Color Is Your Parachute? by Richard Nelson Bolles, as it is the foundational and representative literature in the field of career self-help advice. We first look at the white-collar labor market changes in the U.S. and the growth of career self-help advice along with its influence. We then show that What Color Is Your Parachute? seeks to motivate and inspire job seekers by defining job searching in individual terms and overlooking its structural nature. From this, we point out the most problematic aspect of career self-held advice, i.e., shifting job search responsibility as well as its outcome solely to individual job seekers, while also making it difficult to scrutinize and understand the broader context affecting job searching.

Intelligent recommendation method of intelligent tourism scenic spot route based on collaborative filtering

  • Liu Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.5
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    • pp.1260-1272
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    • 2024
  • This paper tackles the prevalent challenges faced by existing tourism route recommendation methods, including data sparsity, cold start, and low accuracy. To address these issues, a novel intelligent tourism route recommendation method based on collaborative filtering is introduced. The proposed method incorporates a series of key steps. Firstly, it calculates the interest level of users by analyzing the item attribute rating values. By leveraging this information, the method can effectively capture the preferences and interests of users. Additionally, a user attribute rating matrix is constructed by extracting implicit user behavior preferences, providing a comprehensive understanding of user preferences. Recognizing that user interests can evolve over time, a weight function is introduced to account for the possibility of interest shifting during product use. This weight function enhances the accuracy of recommendations by adapting to the changing preferences of users, improving the overall quality of the suggested tourism routes. The results demonstrate the significant advantages of the approach. Specifically, the proposed method successfully alleviates the problem of data sparsity, enhances neighbor selection, and generates tourism route recommendations that exhibit higher accuracy compared to existing methods.

A Study on Container Terminal Layout and the Productivity of Container Crane During Ship Turnaround Time (컨테이너 터미널 배치 형태와 본선작업 생산성에 대한 연구)

  • Shin, Sung-Ho;Kim, Yeonkook J.
    • Journal of Korea Port Economic Association
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    • v.39 no.1
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    • pp.47-63
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    • 2023
  • In smart ports and port automation, the number of vertically deployed container terminals is growing. The purpose of this study is to analyze the productivity of horizontally arranged and vertically arranged container terminals by comparing the main ship operation time, and to recommend future strategies for increasing the operational efficiency of vertically configured container terminals. To achieve our goal, we chose two terminals representating each type, and collected berth allocation status data from 2018 to 2022. Then we analyzed the data using the Accelerated Failure Time (AFT) model, a parametric survival analysis technique. Under the assumption that the working circumstances of the C/C (Container Crane) are the same, we find that the productivity of on-board work of the vertically placed container terminal is higher than that of the horizontally placed container terminal. Our result also shows that the productivity is reduced during the COVID-19 period and the European ships show lower onboard work time. On the basis of these findings, we propose strategies to improve the productivity of vertical container terminals.

A Comparative Analysis of Biomechanical Factors and Premotor Time of Body Muscles between Elite College and Amateur Baseball Players during the Baseball Batting Motion

  • Lim, Young-Tae;Kwon, Moon-Seok
    • Korean Journal of Applied Biomechanics
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    • v.26 no.2
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    • pp.205-211
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    • 2016
  • Purpose: The aim of this study was to analyze biomechanical factors and PMT (premotor time) of body muscles between elite college and amateur baseball players during the baseball batting motion. Method: Kinematic and electromyographic data were obtained for 10 elite college baseball players and 10 amateur baseball players who participated in this study. All motion capture data were collected at 200 Hz using 8 VICON cameras and the PMT of muscles was recorded using a Delsys Trigno wireless system. The peak mean bat speed and the peak mean angular velocities of trunk, pelvis, and bat with PMT of 16 body muscles were computed. These kinematic and PMT data of both groups were compared by independent t-tests (p < .05). Results: The pelvis, trunk, and bat showed a sequence of angular velocity value during baseball batting. The PMTs of right tibialis anterior, left gastrocnemius, external oblique, and erector spinae were significantly different between the two groups. Conclusion: The PMT of body muscles was related to the shifting of body and rotation of the pelvis and the trunk segment, and this action can be considered the coordinated muscle activity of the lower and upper body.