• Title/Summary/Keyword: Pivot operation

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Effective Reduction Malarplasty Considering Pivot Point (추축 (Pivot Point)를 고려한 효과적인 관골 축소성형술)

  • Ha, Ju-Ho;Kim, Yong-Ha;Kim, Tae-Gon;Lee, Jun-Ho
    • Archives of Plastic Surgery
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    • v.38 no.3
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    • pp.287-294
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    • 2011
  • Purpose: Reduction malarplasty is one of the common aesthetic procedures performed in the Orient. We have analyzed effective operative methods according to the pivot point for the osteotomy and reposition of the zygoma for reduction malarplasty after confirming the shapes of the individual zygomas. Methods: Thirty-six patients had been received malarplasty over the last 10 years. The average follow-up period was 16 months. We categorized the patients into three groups according to their prominent appearance features. Group I had a prominently protruded zygomatic body, group II had a prominently protruded zygomatic arch, and group III had a prominently protruded body and zygomatic arch. In the group I, two parallel oblique osteotomies on the body, the middle portion was removed, and with the zygomatic arch as the pivot point, the body was repositioned inwards. In the group II, the zygomatic body and arch osteotomy is performed, with the body as the pivot point, and the arch is depressed medially. In the group III, using the two aforementioned methods, the zygoma was repositioned medially. In each case, postoperative complications and patients satisfaction over the surgery were surveyed. Results: Each group had 25, 5 and 12 patients respectively. No significant complications were found except for one patient who experienced a non-union of zygomatic bone. In the case of group I, four patients underwent a secondary operation. Conclusion: Reduction malarplasty is popular as an effective facial contouring surgery. In order to obtain more effective results,however, the zygomatic shape should be identified, and appropriately repositioned by different operative technique according to pivot points.

A PIVOT based Query Optimization Technique for Horizontal View Tables in Relational Databases (관계 데이터베이스에서 수평 뷰 테이블에 대한 PIVOT 기반의 질의 최적화 방법)

  • Shin, Sung-Hyun;Moon, Yang-Sae;Kim, Jin-Ho;Kang, Gong-Mi
    • The KIPS Transactions:PartD
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    • v.14D no.2
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    • pp.157-168
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    • 2007
  • For effective analyses in various business applications, OLAP(On-Line Analytical Processing) systems represent the multidimensional data as the horizontal format of tables whose columns are corresponding to values of dimension attributes. Because the traditional RDBMSs have the limitation on the maximum number of attributes in table columns(MS SQLServer and Oracle permit each table to have up to 1,024 columns), horizontal tables cannot be directly stored into relational database systems. In this paper, we propose various efficient optimization strategies in transforming horizontal queries to equivalent vertical queries. To achieve this goral, we first store a horizontal table using an equivalent vertical table, and then develop various query transformation rules for horizontal table queries using the PIVOT operator. In particular, we propose various alternative query transformation rules for the basic relational operators, selection, projection, and join. Here, we note that the transformed queries can be executed in several ways, and their execution times will differ from each other. Thus, we propose various optimization strategies that transform the horizontal queries to the equivalent vertical queries when using the PIVOT operator. Finally, we evaluate these methods through extensive experiments and identify the optimal transformation strategy when using the PIVOT operator.

Experimental verification of leverage-type stiffness-controllable tuned mass damper using direct output feedback LQR control with time-delay compensation

  • Chu, Shih-Yu;Yeh, Shih-Wei;Lu, Lyan-Ywan;Peng, Chih-Hua
    • Earthquakes and Structures
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    • v.12 no.4
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    • pp.425-436
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    • 2017
  • Vibration control using a tuned mass damper (TMD) is an effective technique that has been verified using analytical methods and experiments. It has been applied in mechanical, automotive, and structural applications. However, the damping of a TMD cannot be adjusted in real time. An excessive mass damper stroke may be introduced when the mass damper is subjected to a seismic excitation whose frequency content is within its operation range. The semi-active tuned mass damper (SATMD) has been proposed to solve this problem. The parameters of an SATMD can be adjusted in real time based on the measured structural responses and an appropriate control law. In this study, a stiffness-controllable TMD, called a leverage-type stiffness-controllable mass damper (LSCMD), is proposed and fabricated to verify its feasibility. The LSCMD contains a simple leverage mechanism and its stiffness can be altered by adjusting the pivot position. To determine the pivot position of the LSCMD in real time, a discrete-time direct output-feedback active control law that considers delay time is implemented. Moreover, an identification test for the transfer function of the pivot driving and control systems is proposed. The identification results demonstrate the target displacement can be achieved by the pivot displacement in 0-2 Hz range and the control delay time is about 0.1 s. A shaking-table test has been conducted to verify the theory and feasibility of the LSCMD. The comparisons of experimental and theoretical results of the LSCMD system show good consistency. It is shown that dynamic behavior of the LSCMD can be simulated correctly by the theoretical model and that the stiffness can be properly adjusted by the pivot position. Comparisons of experimental results of the LSCMD and passive TMD show the LSCMD with less demand on the mass damper stroke than that for the passive TMD.

An Algorithm for One-Sided Generalized Least Squares Estimation and Its Application

  • Park, Chul-Gyu
    • Journal of the Korean Statistical Society
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    • v.29 no.3
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    • pp.361-373
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    • 2000
  • A simple and efficient algorithm is introduced for generalized least squares estimation under nonnegativity constraints in the components of the parameter vector. This algorithm gives the exact solution to the estimation problem within a finite number of pivot operations. Besides an illustrative example, an empirical study is conducted for investigating the performance of the proposed algorithm. This study indicates that most of problems are solved in a few iterations, and the number of iterations required for optimal solution increases linearly to the size of the problem. Finally, we will discuss the applicability of the proposed algorithm extensively to the estimation problem having a more general set of linear inequality constraints.

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Incremental Maintenance of Horizontal Views Using a PIVOT Operation and a Differential File in Relational DBMSs (관계형 데이터베이스에서 PIVOT 연산과 차등 파일을 이용한 수평 뷰의 점진적인 관리)

  • Shin, Sung-Hyun;Kim, Jin-Ho;Moon, Yang-Sae;Kim, Sang-Wook
    • The KIPS Transactions:PartD
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    • v.16D no.4
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    • pp.463-474
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    • 2009
  • To analyze multidimensional data conveniently and efficiently, OLAP (On-Line Analytical Processing) systems or e-business are widely using views in a horizontal form to represent measurement values over multiple dimensions. These views can be stored as materialized views derived from several sources in order to support accesses to the integrated data. The horizontal views can provide effective accesses to complex queries of OLAP or e-business. However, we have a problem of occurring maintenance of the horizontal views since data sources are distributed over remote sites. We need a method that propagates the changes of source tables to the corresponding horizontal views. In this paper, we address incremental maintenance of horizontal views that makes it possible to reflect the changes of source tables efficiently. We first propose an overall framework that processes queries over horizontal views transformed from source tables in a vertical form. Under the proposed framework, we propagate the change of vertical tables to the corresponding horizontal views. In order to execute this view maintenance process efficiently, we keep every change of vertical tables in a differential file and then modify the horizontal views with the differential file. Because the differential file is represented as a vertical form, its tuples should be converted to those in a horizontal form to apply them to the out-of-date horizontal view. With this mechanism, horizontal views can be efficiently refreshed with the changes in a differential file without accessing source tables. Experimental results show that the proposed method improves average performance by 1.2$\sim$5.0 times over the existing methods.

Principle of Rehabilitation after the Arthroscopic Anterior Cruciate Ligament Reconstruction (관절경적 전방 십자인대 재건술 후의 재활 치료 원칙)

  • Kyung Hee-Soo;Kim Hee-Soo
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.2 no.1
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    • pp.6-14
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    • 2003
  • The goal of rehabilitation after ACL reconstruction are return the patient to a reinjury level of activity with stable joint, removing pivot shift phenomenon, preservation of meniscus, restoration of range of motion, and minimize patello-femoral complication. The ACL reconstruction should avoid immediate surgery. The preoperative phase emphasizes two important factors. (1) The patient should have a resolution of knee swelling, a return of full ROM, and a normal gait. (2) The patient should be mentally prepared for the operation and subsequent rehabilitation. The postoperative rehabilitation program emphasizes extension, closed kinetic chain function exercises. The regular follow-up is important.

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Successful Modified Nikaidoh Procedure (Pivot Rotation) in a Patient with Double Outlet Right Ventricle and Pulmonary Atresia: Case Report

  • Lee, Jae Jun;Lee, Ok Jeong;Yang, Ji-Hyuk;Jun, Tae-Gook
    • Journal of Chest Surgery
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    • v.54 no.5
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    • pp.389-392
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    • 2021
  • Double outlet right ventricle (DORV) with pulmonary atresia (PA) is an uncommon congenital disease. Because of anatomical and physiological anomalies in the systemic and pulmonary circulation, corrective surgery may be challenging. We present the case of a patient with DORV and PA. This condition was successfully corrected using a modified Nikaidoh procedure, resulting in reduced obstruction of the left ventricular outflow tract.

Transient Calcification of Autogenous Grafted Patellar Tendon in Anterior Cruciate Ligament Reconstruction - A Case Report - (슬관절 전방 십자 인대 재건술 후 발생한 이식 건의 일과성 석회화 - 증례 보고 -)

  • Chung, Hyun Kee;Choi, Choong Hyeok;Kim, Jong Heon;Kim, Jae Young
    • Journal of the Korean Arthroscopy Society
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    • v.3 no.1
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    • pp.30-34
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    • 1999
  • We report the case of a 30-year-old man who was presented with transient calcification on the graft shortly after anterior cruciate ligament(ACL) reconstruction using a autogenous bone patellar tendon. The patient underwent ACL reconstruction with two incisional technique and six month later, calcific density was seen radiologically around the graft. On postoperative 13 months follow-up radiographic films, the calcific density disappeared. After two months of operation, Lachman and pivot shift test were negative and one millimeter side to side difference was detected in KT-1000 with 20 Ibs strength. But 6 months after the reconstruction, mild anterior instability was detected with the calcific density around the grafted tendon. However the anterior stability was recovered according to the disappearance of calcific density.

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Notchyplasty with Flexible Reamer (대퇴과간절흔 성형술에서 유연성 연마기를 이용한 방법)

  • Chae, In-Jung;Lee, Kwang-Suk;Back, Jong-Ryoon
    • Journal of the Korean Arthroscopy Society
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    • v.1 no.1
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    • pp.123-127
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    • 1997
  • Arthroscopic anterior cruciate ligament reconstructions using bone-patella tendon-bone have been considered the best method by which others are compared. The notchyplasty is one of the important steps of this procedure and it is emphasized recently to prevent retear of the reconstructed ACL caused by impingement. However, until now, there is controversy about adequate amount of notchyplasty. Also, it is hard to examine the adequacy of notchyplasty even in the arthroscopic field, The purpose of this paper is to describe the surgical technique of notchyplasty, using the flexible reamer and preliminary result of its operation. In this study the results of ACL reconstruction with notchyplasty which is made by us were analized from January. 1994 to December, 1995. The results were as follows: 1. The notchyplasty with flexible reamer is the method that can be obtained adequate amount of removal, perfectly smooth notchyplasty. 2. The range of motion of the affected knee joint was normal ROM after post operation 6 month. 3. In the last follow up, 2 cases were positive in anterior drawer test 4 cases were positive in Lachmann's test and 1 knee was positive in Pivot shift test 4. Average Lysholm knee scoring scale was 70 points at preoperative and 92 points at the last follow up.

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The Study on Park Designing for Users of Common Residential Room (공동주거 공간의 이용자 중심형 공원계획에 대한 연구)

  • Cho, Kyoung-Deuk
    • Journal of The Korean Digital Architecture Interior Association
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    • v.7 no.1
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    • pp.35-42
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    • 2007
  • Common residential environment is synthetic forms promote with organic organization of varied cultures and images. Users perceive and classify about these environments of feeling and atmosphere of each elements through their experiences and memories, not fixed point of view. In Korea, park designing of common residential room is in operation monotonously attach importance to economical efficiency without aesthetic structures, varied tries of materials, multiplicity, congruity of surrounding, and user-oriented plan. Recently, in policy of park designing has elements that obstruct to characteristic of environment because of applied to wrong guidelines which are end in investigation to model of an advanced countries'. In conclusion, this investigation shows improve on quality of park planning with the pivot of the matter is for users of common residential room. and park planning needs to multidimensional achieve.

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