• Title/Summary/Keyword: Glide

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A Study on the Maximum Target Distance Using a Flight Simulator of Glide-Type Ammunition (활공형 탄약의 비행모사 시뮬레이터를 활용한 조건별 최대사거리 연구)

  • Shin, Seung-je;Kim, Whan-Woo
    • Journal of Korea Multimedia Society
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    • v.21 no.6
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    • pp.698-704
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    • 2018
  • When the new ammunition is designed, it is necessary to confirm in advance how long the target distance is depends on the shape and weight of the designed ammunition. Therefore we can use commercial software such as PRODAS to predict the target distance in the design stage. This commercial software has aerodynamic data for various ammunition shape and calculates the target range by calculating the kinetic equations of the ammunition using the aerodynamic data most similar to the designed ammunition. The ammunition for predicting the target distance through software such as PRODAS is a non-guided ammunition that has no control after launch but the glide type ammunition is guided and control ammunition. So it is predicts the state of ammunition after the launch. A new type of simulator is needed to analyze the maximum range and to verify the onboard guided and control algorithm. The simulator constructed in this paper is an optimized simulator for glide type ammunition. Unlike unmanned aircraft and guided missiles. The rotation characteristics of the ammunition are considered and the navigation initialization algorithm is applied. The constructed simulator confirmed the performance by performing maximum range analysis of glide type ammunition.

Importance of Accurate Charges in Binding Affinity Calculations: A Case of Neuraminidase Series

  • Park, Kichul;Sung, Nack Kyun;Cho, Art E.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.545-548
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    • 2013
  • It has been shown that calculating atomic charges using quantum mechanical level theory greatly improves the accuracy of docking. A protocol was developed and shown to be effective. That this protocol works is just a manifestation of the fact that electrostatic interactions are important in protein-ligand binding. In order to investigate how the same protocol helps in prediction of binding affinities, we took a series of known cocrystal structures of influenza neuraminidase inhibitors with the receptor and performed docking with Glide SP, Glide XP, and QPLD, the last being a workflow that incorporates QM/MM calculations to replace the fixed atomic charges of force fields with quantum mechanically recalculated ones at a given docking pose, and predicted the binding affinities of each cocrystal. The correlation with experimental binding affinities considerably improved with QPLD compared to Glide SP/XP yielding $r^2$ = 0.83. The results suggest that for binding sites, such as that of neuraminidase, which are laden with hydrophilic residues, protocols such as QPLD which utilizes QM-based atomic charges can better predict the binding affinities.

The Kinematic Difference According to Success and Failure of Shot-Putting - Focusing on Member of the National Team, Hwang, In-sung, Player - (남자 포환던지기 시 성공과 실패에 따른 운동학적 차이 - 국가대표 황인성 선수를 중심으로 -)

  • Ryu, Ji-Seon;Park, Jae-Myoung;Kim, Tae-Sam
    • Korean Journal of Applied Biomechanics
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    • v.21 no.2
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    • pp.161-171
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    • 2011
  • The purpose of this study was to identify biomechanical characteristics of glide and delivery motion of In-Sung Hwang, player who is a member of the national team among the finalists in the men's shot put at the 2010 National Sports Festivals. Three-Dimensional motion analysis using a system of 3 video cameras at a sampling frequency of 60 Hz was performed for this study. During the glide and delivery phase the results showed following characteristics; 1) The glide type was suitable for the short-long technique, but the trajectory of shot at the glide and delivery phase showed a different trajectory pattern with "S-shaped" type of elite players due to many deviating from central axis of the APSS(athletic-plus shot system). 2) Left knee was more flexed during failed trials compared to successful trials but COG was higher. Therefore, the player showed less stability of COG as he may not get enough breaking force at the left foot. 3) Furthermore, it would be required to have strong muscle power at the trunk, throwing arm, and the lower extremity in order to achieve maintain a low projection angle of the release.

Comparative Analysis from Perspective of Kinesiology between Korean Athletes and Gold and Bronze Medalists in Glide-Type Shot Put at Daegu World Athletic Championships in 2011 (2011 대구세계육상선수권대회 Gilde Type 포환던지기 한국선수와 결승 1, 3위 선수와의 운동학적 비교분석)

  • Oh, Chow-Hwan;Choi, Su-Nam;Shin, Eui-Su;Lee, Jeong-Tae;Jeong, Ik-Su;Bae, Jae-Hee;Park, Seung-Bum
    • Korean Journal of Applied Biomechanics
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    • v.21 no.5
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    • pp.645-652
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    • 2011
  • The purpose of this study was to analyze, in real time, the glide motion and release motion of domestic athletes and gold and bronze medalists employing the glide technique for the men's shot put at the Daegu World Athletic Championship in 2011. In the glide motion, the Korean athletes had a relatively high body center and shot put heights and lager stretching angles for their hips and knees. In the delivery phase, which shifts to the release phase, the Korean athletes showed slower vertical body center and shot put speeds, and they changed the phase, to the release phase by using a small body angle. In the release phase, the Korean athletes showed differences in their projection speeds and vertical body center speeds. The world-famous players showed high angle speeds, which refer to the composition of the rotation force at the moment of release (body, hip, and shoulder line). In the release phase, the Korean athletes did not have fully stretched hip and knee angles, which might have negatively influenced the vertical speed. Because the Korean athletes showed relatively low projection heights and projection angles. it was found that they need to enhance the muscular power of their, throwing arms and lower limbs.

Effect of repetitive pecking at working length for glide path preparation using G-file

  • Ha, Jung-Hong;Jeon, Hyo-Jin;Abed, Rashid El;Chang, Seok-Woo;Kim, Sung-Kyo;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.40 no.2
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    • pp.123-127
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    • 2015
  • Objectives: Glide path preparation is recommended to reduce torsional failure of nickel-titanium (NiTi) rotary instruments and to prevent root canal transportation. This study evaluated whether the repetitive insertions of G-files to the working length maintain the apical size as well as provide sufficient lumen as a glide path for subsequent instrumentation. Materials and Methods: The G-file system (Micro-Mega) composed of G1 and G2 files for glide path preparation was used with the J-shaped, simulated resin canals. After inserting a G1 file twice, a G2 file was inserted to the working length 1, 4, 7, or 10 times for four each experimental group, respectively (n = 10). Then the canals were cleaned by copious irrigation, and lubricated with a separating gel medium. Canal replicas were made using silicone impression material, and the diameter of the replicas was measured at working length (D0) and 1 mm level (D1) under a scanning electron microscope. Data was analysed by one-way ANOVA and post-hoc tests (p = 0.05). Results: The diameter at D0 level did not show any significant difference between the 1, 2, 4, and 10 times of repetitive pecking insertions of G2 files at working length. However, 10 times of pecking motion with G2 file resulted in significantly larger canal diameter at D1 (p < 0.05). Conclusions: Under the limitations of this study, the repetitive insertion of a G2 file up to 10 times at working length created an adequate lumen for subsequent apical shaping with other rotary files bigger than International Organization for Standardization (ISO) size 20, without apical transportation at D0 level.

A Study on Dynamic Glide Path of Target Date Fund Reflecting Market Expectations (시장기대를 반영한 타겟 데이트 펀드의 동적 글라이드패스에 관한 연구)

  • Moon, Myung-Deok;Kim, Sun Woong;Choi, Heung Sik
    • Knowledge Management Research
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    • v.22 no.3
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    • pp.17-29
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    • 2021
  • The purpose of this study is to analyze investment performance by applying dynamic methodologies that reflect market expectations rather than traditional static methodologies in applying the glide path of target date fund. In calculating market expectations, the number of distributed shares in the ETF market was used, and the dynamic glide path model portfolio considering market expectations in the analysis period from late 2011 to October 2020 could show better results than the existing static glide path. According to the analysis, increasing the portion of risky assets at a time when the number of shares in the ETF's distribution increases, and in the opposite case, reducing the portion of risky assets is advantageous for profit. The results of this study are expected to provide useful theoretical and practical implications for researchers and asset management workers who are interested in knowledge management from a broad perspective beyond the boundary of pension asset management to the public fund market and ETF market.

An Acoustical Study of Labiovelar Glide /w/ Followed by Labials (양순음 후행 양순전이음 /w/의 음향음성학적 연구)

  • Koo, Hee-San;Han, Hye-Seung
    • Speech Sciences
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    • v.6
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    • pp.45-54
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    • 1999
  • The well-known tendency to delete the labiovelar glide /w/ in some special conditions in Korean was based on perceptual judgment. Among the studies which tried to identify this phenomenon, Silva(1991) and Kang(1997) discovered the important factors of /w/-deletion and tried to give phonological explanations in terms of the Obligatory Contour Principle (McCarthy 1986). This study uses acoustic experiments in order to examine the reality of this phenomenon and tries to explain it on the basis of spectrographic analysis. According to the experiment, it is observed that /w/ is neutralized rather than completely deleted. Therefore, this observation suggests that this phenomena be considered as the /w/-neutralization in the view of acoustic study, instead of the /w/-deletion.

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Effects of the Temperature Glide and Superheat of R407C on the Performance of Evaporator (R407C의 온도구배와 과열도가 증발기 성능에 미치는 영향)

  • 김창덕;전창덕;이진호
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.10
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    • pp.852-859
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    • 2003
  • R407C is considered as an alternative refrigerant of R22 for air conditioners. An experiment was carried out to investigate the characteristics of the evaporation heat transfer and pressure drop for refrigerant R407C flowing in a fin-and-tube heat exchanger used for commercial air-conditioning unit. The experimental data were useful in analyze the effects of the temperature glide and superheat for R407C. Test were conducted at the conditions of inlet refrigerant evaporation temperature of 7$^{\circ}C$, inlet air relative humidity of 50%, and refrigerant mass fluxes varying from 150 to 250 kg/m$^2$s. Representative results show that the heat exchanger performance for R407C evaporation is significantly affected by the change of the flow pattern from two-phase to super-heated vapor flow.

Comparison of the centering ability of Wave.One and Reciproc nickel-titanium instruments in simulated curved canals

  • Lim, Young-Jun;Park, Su-Jung;Kim, Hyeon-Cheol;Min, Kyung-San
    • Restorative Dentistry and Endodontics
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    • v.38 no.1
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    • pp.21-25
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    • 2013
  • Objectives: The aim of this study was to evaluate the shaping ability of newly marketed single-file instruments, Wave One (Dentsply-Maillefer) and Reciproc (VDW GmbH), in terms of maintaining the original root canal configuration and curvature, with or without a glide-path. Materials and Methods: According to the instruments used, the blocks were divided into 4 groups (n = 10): Group 1, no glide-path / Wave One; Group 2, no glide-path / Reciproc; Group 3, #15 K-file / Wave One; Group 4, #15 K-file / Reciproc. Pre- and post-instrumented images were scanned and the canal deviation was assessed. The cyclic fatigue stress was loaded to examine the cross-sectional shape of the fractured surface. The broken fragments were evaluated under the scanning electron microscope (SEM) for topographic features of the cross-section. Statistically analysis of the data was performed using one-way analysis of variance followed by Tukey's test (${\alpha}$ = 0.05). Results: The ability of instruments to remain centered in prepared canals at 1 and 2 mm levels was significantly lower in Group 1 (p < 0.05). The centering ratio at 3, 5, and 7 mm level were not significantly different. Conclusions: The Wave One file should be used following establishment of a glide-path larger than #15.

In vitro comparison of the cyclic fatigue resistance of HyFlex EDM, One G, and ProGlider nickel titanium glide path instruments in single and double curvature canals

  • Yilmaz, Koray;Uslu, Gulsah;Ozyurek, Taha
    • Restorative Dentistry and Endodontics
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    • v.42 no.4
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    • pp.282-289
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    • 2017
  • Objectives: It was aimed to compare the cyclic fatigue resistances of ProGlider (PG), One G (OG), and HyFlex EDM (HEDM) nickel titanium glide path files in single- and double-curved artificial canals. Materials and Methods: 40 PG (16/0.02), 40 OG (14/0.03), and 40 HEDM (10/0.05) single-file glide path files were used in the present study. Sixty files were subjected to cyclic fatigue test by using double-curved canals and 60 files by using single-curved canal (n = 20). The number of cycles to fracture (NCF) was calculated and the length of the fractured fragment (FL) was determined by a digital micro-caliper. Twelve pieces of fractured files were examined with scanning electron microscope to determine fracture types of the files (n = 2). The NCF and the FL data were analyzed using one-way analysis of variance and post hoc Tukey test using SPSS 21 software (p < 0.05). Results: In all of the groups, NCF values were significantly lower in double-curved canals when compared to single-curved canals (p < 0.05). For both of single- and double-curved canals, NCF values of HEDM group in apical and coronal curvatures were found to be significantly higher than NCF values of PG and OG groups (p < 0.05). In both of single- and double-curved canals, NCF value of PG group was found significantly higher than OG group (p < 0.05). Conclusions: Within the limitations of this study, HEDM glide path files were found to have the highest cyclic fatigue resistance in both of single- and double-curved canals.