• 제목/요약/키워드: Segmental analysis

검색결과 294건 처리시간 0.025초

Transforaminal Lumbar Interbody Fusion Using Wedged Cages for Isthmic Spondylolisthesis : A Short-Term Radiological Analysis

  • Lee, Dong-Yeob;Lee, Sang-Ho;Lee, Han-Soon
    • Journal of Korean Neurosurgical Society
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    • 제40권5호
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    • pp.346-350
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    • 2006
  • Objective : The ability to induce segmental lordosis has been reported to be marginal with transforaminal lumbar interbody fusion[TLIF]. Therefore, we analyzed the short-term radiological outcomes of TLIF using $8^{\circ}$ wedged cages for isthmic spondylolisthesis. Methods : Twenty-seven patients with isthmic spondylolisthesis who underwent single level TLIF with pedicle screw fixation[PSF] using $8^{\circ}$ wedged cages were retrospectively evaluated. Changes in disc height, degree of anterolisthesis, segmental lumbar lordosis, whole lumbar lordosis and L1 axis S1 distance were evaluated using standing lateral radiographs before surgery, at 6 weeks follow-up and at the final follow-up. Results : The mean age of the patients was 49.9 years [range, 38 to 64 years]. The affected levels were L4-5 in 17 cases and L5-S1 in 10. There were 18 cases of Grade I isthmic spondylolisthesis and 9 cases of Grade II. At a mean follow-up duration of 9.9 months [range, 6 to 18 months], the disc height [p< 0.001] was significantly increased, and the degree of anterolisthesis was significantly reduced [p< 0.001]. Regarding the sagittal balance, the segmental lumbar lordosis was significantly increased [p=0.01], but other parameters were not significantly changed after surgery. Conclusion : TLIF with PSF using $8^{\circ}$ wedged cages significantly increased the segmental lumbar lordosis.

세그멘탈 PSC박스거더교량의 시공간 계측모니터링을 통한 확률적 구조안정성 평가 및 제어 시스템 (Safety Assessment and Behavior Control System using Monitoring of Segmental PSC Box Girder Bridges during Construction)

  • 신재철;조효남;박경훈;배용일
    • 한국구조물진단유지관리공학회 논문집
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    • 제5권3호
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    • pp.191-201
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    • 2001
  • In spite of the increasing construction of segmental PSC box girder bridges, the techniques associated with real-time monitoring, construction control and safety assessment during construction have been less developed compared with the construction techniques. Thus, the development of an integrated system including real-time measurement and monitoring, control and safety assessment system during construction is necessary fur more safe and precise construction of the bridges. This study presents a prototype integrated monitoring system for preventing abnormal behavior and accidents under construction stages, that consist of behavior control system for precise construction, reliability-based safety assessment system, and structural analysis. Also, a prototype software system is developed on the basis of the proposed model. It is successfully applied to the Sea-Hae Grand Bridge built by FCM. The integrated system model and software system can be utilized for the safe and precise construction of segmental PSC bridges during construction.

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뇌졸중 후 복합부위통증증후군에서 부위별 위상각을 이용한 평가 (Application of Segmental Phase Angle for Assessment of Post-Stroke Complex Regional Pain Syndrome)

  • 박세흠;김우진;조근열;권준구
    • Clinical Pain
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    • 제19권1호
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    • pp.23-27
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    • 2020
  • Our objective is to evaluate the applicability of segmental phase angle (PhA) via bioelectrical impedance analysis (BIA) for post-stroke complex regional pain syndrome (CRPS). Due to its noninvasiveness and convenience, various studies have used BIA in clinical conditions. We measured segmental PhA in 4 patients at the time of CRPS diagnosis and repeated 4 weeks after 2 weeks of steroid pulse therapy. In 3 cases, the affected-to-unaffected ratio of the upper limb PhA decreased at the time of diagnosis. In 2 cases with improvement of more than 5 points in the CRPS severity score (CSS), increased ratios were observed. In other 2 cases with improvement of less than 4 points in the CSS, no remarkable changes in the ratios were found. We suggest that the segmental PhA can be helpful in assessment of post-stroke CRPS and its recovery.

단일치 권선을 가지는 분절회전자형 12/8SRM의 설계 및 특성해석 (Design and Characteristics Analysis of Segmental Rotor Type 12/8 poles SRM with single teeth windings)

  • 정광일;이동희;안진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2014년도 추계학술대회 논문집
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    • pp.39-40
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    • 2014
  • In this paper, a novel 12/8 segmental rotor type switched reluctance motor (SRM) is proposed. Different from conventional structures, the proposed rotor consists of a series of discrete segments, and the stator is constructed from two types of stator poles: exciting and auxiliary poles. Moreover, in this structure short flux paths are taken and no flux reverse exists in the stator. While the auxiliary poles are not wound by the windings, which only provide the flux return path. Compared with conventional 12/8 SRM, the proposed structure increases the electrical utilization of the machine and decreases the core losses, which may lead to high efficiency. To verify the proposed structure, finite element method (FEM) is employed to get static and dynamic characteristics. Finally, a prototype of the proposed motor is tested for characteristics comparisons.

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보강토 옹벽의 설계 현황에 대한 고찰 (Review of Current Design Practice for Soil-Reinforced Segmental Retaining Walls)

  • 유충식
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 토목섬유 특별세미나
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    • pp.41-50
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    • 2000
  • Segmental retaining wall market in Korea has been growing dramatically since late 1990s in both engineered and non-engineered applications. Despite the inherent conservatism in the current design approaches, numerous major and minor structural problems have been reported during and after construction, covering a range of minor structural damage to total collapse. Much still needs to be investigated to fill the gap between the theory and the practice. This paper reviews several design issues with regard to the segmental retaining walls such as the selection of shear strength parameters for backfill soil, local stability, and tiered wall construction. In addition, the effects of shear strength parameters and the fundamental behavior of tiered SRWs are examined based on the results of finite element analysis. Implications of the findings from this study to current design practices were discussed in detail.

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상재하중이 블록식 보강토 옹벽의 거동에 미치는 영향 (Effects of Surface Loading on the Behavior of Soil-Reinforced Segmental Retaining Walls)

  • 유충식;김주석
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.109-116
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    • 2000
  • This paper presents the results of investigation on the effects of surface loading on the performance of soil-reinforced segmental retaining walls using the finite element method of analysis. A parametric study was performed by varying location of surface loading. The results of the analyses indicate that the increment of the reinforcement tensile load due to the presence of surface load may be significantly over-estimated when using the conventional approach. Furthermore, the external stability should be carefully examined when a surface loading is present just outside the reinforced soil zone. The implications of the findings from this study to current design approaches are discussed in detail.

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비원어민 한국어 말하기 숙련도 평가와 평가항목의 상관관계 (Correlation analysis of linguistic factors in non-native Korean speech and proficiency evaluation)

  • 양승희;정민화
    • 말소리와 음성과학
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    • 제9권3호
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    • pp.49-56
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    • 2017
  • Much research attention has been directed to identify how native speakers perceive non-native speakers' oral proficiency. To investigate the generalizability of previous findings, this study examined segmental, phonological, accentual, and temporal correlates of native speakers' evaluation of L2 Korean proficiency produced by learners with various levels and nationalities. Our experiment results show that proficiency ratings by native speakers significantly correlate not only with rate of speech, but also with the segmental accuracies. The influence of segmental errors has the highest correlation with the proficiency of L2 Korean speech. We further verified this finding within substitution, deletion, insertion error rates. Although phonological accuracy was expected to be highly correlated with the proficiency score, it was the least influential measure. Another new finding in this study is that the role of pitch and accent has been underemphasized so far in the non-native Korean speech perception studies. This work will serve as the groundwork for the development of automatic assessment module in Korean CAPT system.

한국인에서의 분절골 절단술 후 연조직 변화의 평가 (Evaluation of Soft Tissue Change after Segmental Osteotomy in Korean)

  • 박재억
    • 대한치과교정학회지
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    • 제28권6호
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    • pp.975-979
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    • 1998
  • 하악 전치부 근첨하 골전단술을 동반한 상악 변형 분절골 절단술 목적은 양치조성 혹은 양악 전돌 환자로부터 가장 좋은 치료 결과를 얻는 것이다. 본 연구에서는 두부방사선 계측 분석과 정면 사진을 비교 분석해 술 후 연조직 변화를 조사하였다. 구순 전돌이 효과적으로 감소되었으며 비순각은 증가하였다. 코가 약간 넓어졌으나 결과는 비교적 양호하였다. 절단된 골분절의 혈액공급은 잘 유지되었다. 이것은 많은 환자에게 적용할 수 있는 비교적 간단한 수술법이다.

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분리형 보강토공법의 고속도로 적용사례 (A Case Study on the Discrete Segmental Retaining Wall in Highway Construction)

  • 노한성;최영철
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 가을 학술발표회 논문집
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    • pp.337-344
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    • 2001
  • The application of mechanically stabilized earth wall(MSEW) with segmental front panel has been increasing in highway construction due to its cost-effectiveness. However, some failures during construction have been reported and many field engineers are reluctant to select this method for important structure. One of the main reasons may be that there is no moderate specification for design and construction of MSEW yet. This paper discussed the main results of analysis on a case of block-type segmental retaining wall in highway construction. Based on the results, some recommendations on design and construction method of MSEW are presented.

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모사열차 반복하중 재하시 블록식 보강토 옹벽의 진동전달특성 (Vibration Transfer Characteristics of the Reinforced Soil SRWs Under the Simulated Cyclic Train Loading)

  • 고태훈;이진욱;이성혁;황선근;김정무
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(I)
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    • pp.626-632
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    • 2002
  • Geogrid is widely used as the reinforcement materials in railway earth structures in order to achieve efficient land utilization as well as securing safety in railway service lines in other countries. In this study, the real scale test was carried out to investigate the application of geogrid reinforced soil segmental retaining walls(SRWs) in railway. For this goal, the vibration transfer characteristics of reinforced soil segmental retaining walls was evaluated. The resonant frequencies of SRWs, vertical ground vibration in backfill and vertical/horizontal vibration at segmental units were acquired. This experimental data and analysis result can contribute to understand the vibration response behavior of SRWs.

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