• Title/Summary/Keyword: trial

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Identification of Four-DOF Dynamics of a RIB using Sea Trial Tests (I) - Sea Trial Test, Resistance and Propulsion Model (해상시험 결과를 이용한 RIB의 4자유도 동력학 식별 (I) - 해상시험, 저항·추진 모델)

  • Yoon, Hyeon-Kyu;Yun, Kun-Hang;Park, In-Hong
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.1
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    • pp.8-14
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    • 2011
  • RIB(Rigid Inflatable Boat) is widely used for coastal transportation in the commercial use and for ISR(Intelligence, Surveillance, Reconnaissance) in the military use. Since RIB is around 10 meters in length and over 30 knots in speed, its motion characteristics in waves is quite different from a large scale ship. When it turns, large roll occurs and heeling direction is opposite to the large ship's case. Currently, many countries are developing USV(Unmanned Surface Vehicle) of which type is RIB. In order to develop high performance autopilot and way point controller, it is very important to identify RIB's motion characteristics. In this paper, sea trial test results of a 7-meter RIB such as speed, turning, zig-zag, and way point control tests were represented and its resistance and propulsion model was identified by using sea trial data and Savitsky's formula. In addition, the state space model which will be used in the identification of the four-degree-of-freedom dynamics in the next step was formulated and the identification procedure was proposed.

Rapid Manufacturing of Trial Molds and Prototypes by High Speed Machining (고속가공을 이용한 시작금형 및 시작품의 쾌속제작)

  • Sin, Bo-Seong;Yang, Dong-Yeol;Choe, Du-Seon;Je, Tae-Jin;Lee, Eung-Suk;Hwang, Gyeong-Hyeon;Lee, Jong-Hyeon;J. H.
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.12
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    • pp.124-129
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    • 2001
  • Recently, life cycle and lead-time of products have been shortened with the demand of customers. Therefore, it is important to reduce time and cost at the step of manufacturing trial molds. High speed machining can be applied for this kind of purpose with a lot of practical advantages. In our research, several fundamental experiments are carried out to obtain machining parameters such as cutting force, machining time and surface characteristics for tool paths that are appropriate to high-speed machining. Moreover, a trial mold for an automatic transmission knob is fabricated with aluminum-7075 material. Using automatic set-up equipments, an ABS rapid prototype of a trial product of an AT knob is also manufactured with a filling process.

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Pregabalin versus Gabapentin Efficacy in the Management of Neuropathic Pain Associated with Failed Back Surgery Syndrome

  • Laith Thamer Al-Ameri;Mohammed Emad Shukri;Ekhlas Khalid Hameed;Ahmed Abed Marzook
    • Journal of Korean Neurosurgical Society
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    • v.67 no.2
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    • pp.202-208
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    • 2024
  • Objective : Failed back surgery syndrome (FBSS) is a common long-term complication following spine surgeries characterized by chronic persistent pain; different strategies of management were employed to deal with it. This clinical trial aims to compare the efficacy of Pregabalin and Gabapentin in the management of this condition. Methods : A double-blind, randomized, comparative study (clinical trial registry NCT05324761 on 11th April 2022) with two parallel arms with Pregabalin and Gabapentin were used in arms one and two, respectively. Visual analog scale was used for basal and endpoint assessment of pain. T-test and analysis of covariance were used to deal with different variables. A pairwise test was used to compare pairs of means. Results : Of 66 patients referred to the trial, 64 were eligible, with 60 patients completing the 30 days trial. Both pregabalin and gabapentin effectively reduce pain, with significant p-values of 0.001 for each group. However, the pregabalin group was superior to gabapentin in pain reduction (p=0.001). Gender was an insignificant factor (p=0.574 and p=0.445 for the pregabalin and gabapentin groups, respectively, with a non-significant reduction (p=0.393) for both groups in total. Location of stenosis before surgery and type of surgery performed show non-significant effect on pain reduction for both groups. Conclusion : Both pregabalin and gabapentin effectively and safely relieve neuropathic pain associated with FBSS; pregabalin was significantly more effective irrespective of the patients' gender.

Analysis on the Propulsive Performance of Full Scale Ship (실선의 추진성능 해석기법에 관한 연구)

  • Yang, Seung-Il;Kim, Eun-Chan
    • 한국기계연구소 소보
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    • s.9
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    • pp.183-191
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    • 1982
  • This report describes the analysis method of the full-scale propulsive performance by using the data of model test and the full-scale speed trial. The model test data were analyzed by the computer program "PPTT" based on "1978 ITTC Performance Prediction Method for Single Screw Ships." Also the full-scale speed trial data were analyzed by the computer program "SSTT" based on the newly proposed “SRS-KIMM Standard Method of Speed Trial Analysis." An analysis of model and full-scale test data was carried out for a 60.000 DWT Bulk Carrier and the correlation between model and full-scale ship was stuied.

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A Study on the Multiple Trial of Unrelated Question Models

  • Lee, Gi-Sung;Hong, Ki-Hak
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.1
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    • pp.25-34
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    • 2002
  • In this paper, we proposed multiple trial unrelated question models that more efficient by reducing the variance of the estimate than single trial unrelated question models investigated by Greenberg et al.'s (1969) and Kim et al.'s (1992) an d Lee & Hong's (1998).

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A study on field trial system for automatic meter reading and load control system (수용가 자동원방검침 및 부하집중제어 시스템 현장 실증시험연구)

  • 이원빈;문홍석;김석구;양완식
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.663-668
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    • 1988
  • A study on Automatic Meter Reading and Load Control System used to Distribution Line Carrer has started since 1986, and the field trial system for AMR and LCS was installed to KEPCO on June, 1988. Now this system will be operated for testing. This paper will describe project and planning for field trial of KEPCO.

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A TRIAL SOLUTION APPROACH TO THE GI/M/1 QUEUE WITH N-POLICY AND EXPONENTIAL VACATIONS

  • Chae, Kyung-Chul;Lee, Sang-Min;Kim, Nam-Ki;Kim, Jin-Dong;Lee, Ho-Woo
    • Journal of the Korean Statistical Society
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    • v.33 no.3
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    • pp.283-298
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    • 2004
  • We present a trial solution approach to GI/M/l queues with generalized vacations. Specific types of generalized vacations we consider are N -policy and a combination of N-policy and exponential multiple vacations. Discussions about how to find trial solutions are given.

Postoperative Adjuvant Radiotherapy for Patients with Gastric Adenocarcinoma

  • Lim, Do Hoon
    • Journal of Gastric Cancer
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    • v.12 no.4
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    • pp.205-209
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    • 2012
  • In gastric adenocarcinoma, high rates of loco-regional recurrences have been reported even after complete resection, and various studies have been tried to find the role of postoperative adjuvant therapy. Among them, Intergroup 0116 trial was a landmark trial, and demonstrated the definite survival benefit in adjuvant chemoradiotherapy, compared with surgery alone. However, the INT 0116 trial had major limitation for global acceptance of the INT 0116 regimen as an adjuvant treatment modality because of the limited lymph node dissection. Lately, several randomized studies that were performed to patients with D2-dissected gastric cancer were published. This review summarizes the data about patterns of failure after surgical resection and the earlier prospective studies, including INT 0116 study. Author will introduce the latest studies, including ARTIST trial and discuss whether external beam radiotherapy should be applied to patients receiving extended lymph node dissection and adjuvant chemotherapy.