• Title/Summary/Keyword: Inverted

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Efficient Inverted List Search Technique using Bitmap Filters (비트맵 필터를 이용한 효율적인 역 리스트 탐색 기법)

  • Kwon, In-Teak;Kim, Jong-Ik
    • The KIPS Transactions:PartD
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    • v.18D no.6
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    • pp.415-422
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    • 2011
  • Finding similar strings is an important operation because textual data can have errors, duplications, and inconsistencies by nature. Many algorithms have been developed for string approximate searches and most of them make use of inverted lists to find similar strings. These algorithms basically perform merge operations on inverted lists. In this paper, we develop a bitmap representation of an inverted list and propose an efficient search algorithm that can skip unnecessary inverted lists without searching using bitmap filters. Experimental results show that the proposed technique consistently improve the performance of the search.

Design and Application of Subsurface Drainage Devices for Multipurpose Farmland

  • Jeon, Jong Gil;Choi, Yong Hun;Kim, Min Young;Kim, Young Gjin
    • Journal of Biosystems Engineering
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    • v.42 no.4
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    • pp.265-275
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    • 2017
  • Purpose: This study aims to identify the most stable boring shape among the circle, square, and inverted-triangle types in order to be applied to the development of a tractor-pulled underdrain boring device. Methods: The underdrain boring devices designed with the circle, inverted triangle, and square types were analyzed by numerical analysis, and they were evaluated by soil moisture and underground water level in the test field. Results: The results of the numerical analysis indicated that the increases in displacement, and strain when a uniform load is placed on the surface soil with soil weight were in the order of the inverted-triangle type, square type, and circle type. The soil moisture content and the underground water level after rainfall showed the largest difference in the order of the circle type, square type, and inverted-triangle type, indicating that the circle type had the largest drainage effects after rainfall. Conclusions: The overall findings of this study show that the circle type is the most stable among the circle, square, and inverted-triangle types.

An Inverted-F Antenna for 2,4/5 GHz WLAM Applications (2.4/5 GHz 무선랜 대역용 Inverted-F 안테나)

  • Chae, Gyoo-Soo;Cho, Young-Ki;Lim, Joong-Su
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.2
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    • pp.183-187
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    • 2004
  • An inverted-F antenna for wireless local area network(WLAN) is presented. The proposed design is based on the typical dual-band planar inverted-F antennas(PIFA), which have two tunable resonant modes. The low-profile antenna is built by stamping and designed to be mounted on the metal frame of the laptop LCD panel. The obtained antenna can perform in 2.4 GHz and 5 GHz bands and be adopted for other wireless applications. All the measurements are performed in the actual test fixture.

Multivariate Process Capability Index Using Inverted Normal Loss Function (역정규 손실함수를 이용한 다변량 공정능력지수)

  • Moon, Hye-Jin;Chung, Young-Bae
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.2
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    • pp.174-183
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    • 2018
  • In the industrial fields, the process capability index has been using to evaluate the variation of quality in the process. The traditional process capability indices such as $C_p$, $C_{pk}$, $C_{pm}$ and $C^+_{pm}$ have been applied in the industrial fields. These traditional process capability indices are mainly applied in the univariate analysis. However, the main streams in the recent industry are the multivariate manufacturing process and the multiple quality characteristics are corrected each other. Therefore, the multivariate statistical method should be used in the process capability analysis. The multivariate process indices need to be enhanced with more useful information and extensive application in the recent industrial fields. Hence, the purpose of the study is to develop a more effective multivariate process index ($MC_{pI}$) using the multivariate inverted normal loss function. The multivariate inverted normal loss function has the flexibility for the any type of the symmetrical and asymmetrical loss functions as well as the economic information. Especially, the proposed modeling method for the multivariate inverted normal loss function (MINLF) and the expected loss from MINLF in this paper can be applied to the any type of the symmetrical and asymmetrical loss functions. And this modeling method can be easily expanded from a bivariate case to a multivariate case.

A case report of an inverted papilloma infiltrating into maxillary sinus (상악동을 침범하는 역위성 유두종의 증례보고)

  • Ji, Yong-Hwa;Choi, Bo-Ram;Huh, Kyung-Hoe;An, Chang-Hyeon;Lee, Sam-Sun
    • Imaging Science in Dentistry
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    • v.39 no.2
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    • pp.103-107
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    • 2009
  • The present study reports a case of inverted papilloma of the nasal cavity and infiltrating into the maxillary sinus. Inverted papilloma is an uncommon and locally aggressive benign tumor of the sinonasal region. The patient, 51year-old male, presented with unilateral nasal obstruction and periodic swelling on the palate without pain. Enhanced CT scan revealed a heterogeneously enhancing solid mass in the nasal cavity and infiltrating into the right maxillary sinus, as well as an incidental, secondarily infected residual cyst in the periapical area of the right maxillary canine. The sinonasal mass was revealed as an inverted papilloma on histopathologic examination. (Korean J Oral Maxillofac Radiol2009; 39: 103-7)

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Inverted OLED Structure for 3.5 inch Full Color AMOLED Display on a-Si TFT Backplane

  • Park, Jae-Hee;Park, Jae-Young;Hwang, Kwang-Jo;Choi, Hee-Dong;Myoung, Nho-Hoon;Lee, Seok-Jong;Park, Seung-Chul;Kim, Jung-Bum;Hahm, Yun-Hye;Noh, Jeoung-Kwen;Lee, Jung-Hyoung;Kim, Jong-Seok;Kang, Min-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.51-54
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    • 2007
  • Top-emission 3.5 inch qVGA IOD (Inverted AMOLED) was fabricated with inverted EL structure driven by a-Si TFT backplane. In order to get stable driving TFT, we used FCP(Field Control Plate) layer which was connected with the source of the driving TFT. And we developed planarization process to planarize the cathode layer which was the bottom layer of inverted OLED. Our unique IOD structure is “a-Si TFT/ Al(Cathode)/ LiF/ LG-201(ETL)/ EML(RGB)/ HTL/ LG-101(HIL & Buffer layer)/ IZO(Anode)”. LG-201(ETL) layer was studied for more efficient electron injection from cathode to EML, and LG-101(HIL & Buffer layer) covered by IZO anode was also explored for decreasing the EL surface damage.

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A Study on the Stability of Dynamic Walking of a Humanoid Robot (휴머노이드 로봇의 동보행 안정도에 관한 연구)

  • Lee, Ji-Young;Cho, Jung-San;Lee, Sang-Jae
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.2
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    • pp.125-130
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    • 2016
  • In this paper, we deal with the dynamic walking of a humanoid robot. In our method, the inverted pendulum model is used as a dynamic model for a humanoid robot in which the Zero Moment Point (ZMP) and COG constraints of the robot are analyzed by considering the motion of the robot as that of an inverted pendulum. The motion of a humanoid robot should be generated by considering the dynamics of the robot, which commonly requires a large amount of computation. If a robot walks from one position to another while keeping the ZMP in the stable region, then the robot remains dynamically stable. The linear inverted pendulum model regards the whole robot as a point mass. It is simple, and relatively less computation is needed; however, it cannot model the whole dynamics of a humanoid robot. We propose a method for modeling a humanoid robot as an inverted pendulum system having 14 point masses. We also show that the dynamic stability of a humanoid robot can be determined more precisely by our method.

A Control of Mobile Inverted Pendulum using Single Accelerometer (단일 가속도 센서에 의한 모바일 역진자 제어)

  • Ha, Hyun-Uk;Lee, Jang-Myung
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.5
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    • pp.440-445
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    • 2010
  • This paper proposes a single accelerometer sensor control algorithm to mobile inverted pendulum, generally called 'Segway', and evaluates the performance of this system comparing to the conventional ones. The commercialized 'Prototype Segway-PT' is initially considered as a next-generation transport vehicle. However, this robot is operated by three gyroscopes and two accelerometers to control the posture and speed, and it requires the complex signal processing for fusing the two sets of data. As the result of this, the growth rate of market size of 'Segway' is slow because of its high price mainly. In this paper, the mobile inverted pendulum is operated by a single accelerometer to simplify the control system to lower the price. Low pass filter is one of the good sensors to reducing the variation of an accelerometer, but it has time delay. This time delay disturbs real-time mobile inverted pendulum control. Like this, other various algorithms are used for this system, but each one has its own weak point. So this paper proposes a new filtering method, median filter and EKF. Median filter is used to image processing to reject impulse elements like salt and pepper noise. As the major performance evaluation parameter for the accelerometer, the high-frequency to low frequency ratio from FFT (Fast Fourier Transform) is used. Effectiveness of the proposed algorithms has been verified through the real experiments and the results are demonstrated.

A Study of the Flower-Shaped Silver Crown Ornament and Inverted Triangle-Shaped Crown Ornament of Baekje During the Sabi Period (백제 사비기 은화관식과 역삼각형 관식에 관한 연구)

  • Jun-Hee Kweon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.47 no.2
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    • pp.392-408
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    • 2023
  • This study concerns the flower-shaped silver crown ornament and inverted triangle-shaped crown ornament of Baekje, which were worn frequently during the Sabi period. The purpose of this study is to present a new estimated shape of the crown and ornaments. Individual excavation cases and archaeological data were analyzed. The flower-shaped silver crown ornament appears as a thin silver plate with buds on the center and side branches and is symmetrically bent from the center to form a ∧ shape. The inverted triangle-shaped crown ornament resembles two right-angle triangles that are back-to-back. The crown to which the two ornaments were added appears to be a triangular crown that was made by covering birch bark of with fabric. Both ornaments were believed to have been located on the front of crown, but that is incorrect. The flower-shaped silver crown ornament was inserted on the front of the crown, and the inverted triangle-shaped crown ornament was fixed with a tip at the top of the crown and then obliquely on the crown's side. The inferred design was confirmed with real reproductions. This study is significant in that it identifies the crown of Baekje during the Sabi period.

Robust adaptive fuzzy controller for an inverted pendulum

  • Seo, Sam-Jun;Kim, Dong-Sik
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1267-1271
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    • 2003
  • This paper proposes an indirect adaptive fuzzy controller for general SISO nonlinear systems. No a priori information on bounding constants of uncertainties including reconstruction errors and optimal fuzzy parameters is needed. The control law and the update laws for fuzzy rule structure and estimates of fuzzy parameters and bounding constants are determined so that the Lyapunov stability of the whole closed loop system is guaranteed. The computer simulation results for an inverted pendulum system show the performance of the proposed robust adaptive fuzzy controller.

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