• Title/Summary/Keyword: Ranges

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Adaptive Range-Based Collision Avoidance MAC Protocol in Wireless Full-duplex Ad Hoc Networks

  • Song, Yu;Qi, Wangdong;Cheng, Wenchi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.6
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    • pp.3000-3022
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    • 2019
  • Full-duplex (FD) technologies enable wireless nodes to simultaneously transmit and receive signal using the same frequency-band. The FD modes could improve their physical layer throughputs. However, in the wireless ad hoc networks, the FD communications also produce new interference risks. On the one hand, the interference ranges (IRs) of the nodes are enlarged when they work in the FD mode. On the other hand, for each FD pair, the FD communication may cause the potential hidden terminal problems to appear around the both sides. In this paper, to avoid the interference risks, we first model the IR of each node when it works in the FD mode, and then analyze the conditions to be satisfied among the transmission ranges (TRs), carrier-sensing ranges (CSRs), and IRs of the FD pair. Furthermore, in the media access control (MAC) layer, we propose a specific method and protocol for collision avoidance. Based on the modified Omnet++ simulator, we conduct the simulations to validate and evaluate the proposed FD MAC protocol, showing that it can reduce the collisions effectively. When the hidden terminal problem is serious, compared with the existing typical FD MAC protocol, our protocol can increase the system throughput by 80%~90%.

Biomechanical Comparisons of Kettlebell Two-arm Swings according to Somatosensory Interventions for Beginners: Focusing on Joint Ranges of Motion and Muscle Activations (체성감각 처치를 초보자에게 적용한 케틀벨 투암 스윙의 운동역학적 효과 비교: 관절 가동범위와 근활성도를 중심으로)

  • Back, Yei-Chang;Kim, Young-Kwan
    • Korean Journal of Applied Biomechanics
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    • v.29 no.2
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    • pp.89-96
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    • 2019
  • Objective: The purpose of this study was to investigate biomechanical comparisons of kettlebell two-arm swings after different somatosensory interventions on joint ranges of motion (ROM) and muscle activations. Method: Fourteen kettelbell novices (age: $22.92{\pm}3.23yrs$, mass: $75.75{\pm}9.94kg$, height: $172.03{\pm}5.49cm$), consisting of male college students, participated in this study and performed two-arm kettlebell swings in different conditions. Three different somatosensory interventions were the applications of heavy mass kettlebell (20 kg), taping on gluteus muscles, and unstable mat condition. All subjects performed pre-intervention swings and post-intervention swings, respectively. Statistical analysis were performed on results of joint kinematics and electromyographies of major muscles. Results: Results showed significant increases in ROM of hip and decreases in ROM of shoulder after unstable mat trials. In addition, the application of unstable mat during kettlebell swings induced higher muscle activations in gluteus maximus muscle during only upward phase of two-arm kettlebell swings. Conclusion: For beginner, the application of unstable surface would increase in hip joint ranges of motion with enhancement of gluteus muscles.

Developing an approach for fast estimation of range of ion in interaction with material using the Geant4 toolkit in combination with the neural network

  • Khalil Moshkbar-Bakhshayesh;Soroush Mohtashami
    • Nuclear Engineering and Technology
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    • v.54 no.11
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    • pp.4209-4214
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    • 2022
  • Precise modelling of the interaction of ions with materials is important for many applications including material characterization, ion implantation in devices, thermonuclear fusion, hadron therapy, secondary particle production (e.g. neutron), etc. In this study, a new approach using the Geant4 toolkit in combination with the Bayesian regularization (BR) learning algorithm of the feed-forward neural network (FFNN) is developed to estimate the range of ions in materials accurately and quickly. The different incident ions at different energies are interacted with the target materials. The Geant4 is utilized to model the interactions and to calculate the range of the ions. Afterward, the appropriate architecture of the FFNN-BR with the relevant input features is utilized to learn the modelled ranges and to estimate the new ranges for the new cases. The notable achievements of the proposed approach are: 1- The range of ions in different materials is given as quickly as possible and the time required for estimating the ranges can be neglected (i.e. less than 0.01 s by a typical personal computer). 2- The proposed approach can generalize its ability for estimating the new untrained cases. 3- There is no need for a pre-made lookup table for the estimation of the range values.

Study on the Closure Time in Healthy Small-Breed Dogs by Platelet Function Analyzer-200

  • Kyoungyoun Lee;Yoonhee Kim;Ulsoo Choi
    • Journal of Veterinary Clinics
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    • v.40 no.5
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    • pp.330-335
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    • 2023
  • Platelet function evaluation by PFA-100 or -200 has been known to be objective and sensitive for assessing platelet function and dysfunction of Von Willebrand Factor in humans and dogs. However, using the C/EPI cartridge in dogs is controversial. This study aimed to establish a reference range for PFA closure time in healthy small breed dogs (body weight < 10 kg) and to evaluate the effectiveness of both C/ADP and C/EPI cartridges for these dogs. Citrated blood samples were collected from 50 clinically healthy small breed dogs that were admitted for presurgical procedures or health checkups, and closure times were measured using the PFA-200. Reference ranges were determined as 42-144 s (median 67 s, mean 71.2 s, SD ± 21.2 s, 95% RI 43-140 s) , for CT-C/ADP and 41-200 s (median 87, mean 91.2 s, SD ± 31.8 s, 95% RI 44-195 s) for CT-C/EPI. The present study demonstrated that the reference ranges for PFA closure times in small breed dogs are in line with existing reference ranges. The utilization of C/ADP cartridges is the preferred choice for evaluating platelet function in small breed dogs. However, due to variable responses of epinephrine to platelet aggregation in dogs, caution should be exercised when using C/EPI cartridges.

Uncertainty Quantification of Model Parameters Using Reflood Experiments and TRACE Code (재관수 실증실험과 TRACE 코드를 활용한 모델 변수의 불확실도 정량화)

  • Seon Oh Yu;Kyung Won Lee
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.20 no.1
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    • pp.32-38
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    • 2024
  • The best estimate plus uncertainty methodologies for loss-of-coolant accident analyses make use of the best-estimate codes and relevant experimental databases. Inherently, best-estimate codes have various uncertainties in the model parameters, which can be quantified by the dedicated experimental database. Therefore, this study was devoted to establishing procedures for identifying the input parameters of predictive models and quantifying their uncertainty ranges. The rod bundle heat transfer experiments were employed as a representative reflood separate effect test, and the TRACE code was utilized as a best-estimate code. In accordance with the present procedure for uncertainty quantification, the integrated list of the influential input parameters and their uncertainty ranges was obtained through local sensitivity calculations and screening criteria. The validity of the procedure was confirmed by applying it to uncertainty analyses, which checks whether the measured data are within computed ranges of the variables of interest. The uncertainty quantification procedure proposed in this study is anticipated to provide comprehensive guidance for the conduct of uncertainty analyses.

Application Ranges of Finite Difference Models Using Simplified Momentum Equation in Channel Flow simulation (하천흐름 해석에서 단순화된 운동방정식을 사용한 유한차분모델의 신뢰성 있는 적용 범위)

  • Choi, Gye-Woon;Ahn, Kyung-Soo;Ahn, Sang-Jin
    • Water for future
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    • v.27 no.4
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    • pp.123-133
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    • 1994
  • The kinematic and diffusion models using simplified momentum equations of the full dynamic equation have been frequently used for numerical flow simulations, because they have several computational advantages compared to the full dynamic model. In this paper, the more generally acceptable application ranges of the kinematic and diffusion finite difference models were investigated based on three major parameters, which are channel bed slopes So, dimensionless depth increasing numbers Gw at upstream boundary and Froude numbers Fr. The applicable ranges were obtained by comparing the relative magnitudes of the local acceleration, convective acceleration, pressure, gravity and friction terms in the full dynamic equation. In the simulations, a Courant number of 0.5 was used and the channel bed slopes were changed from 0.00001 to 0.05. Also, Froude numbers of 0.1, 0.5 and 0.9 were employed. In this paper, it is indicated that the applicable ranges of kinematic models are increased with increasing of Froude numbers. However, the applicable ranges of diffusion models are decreased with increasing of Froude numbers. Finally, 9 figures were proposed as a guideline in the application of kinematic and diffusion finite difference models based upon the allowable deviation compared to the full dynamic model. With applying the proposed criteria, it is expected that the flow simulations in the channels, streams or rivers are more efficiently achieved.

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Optimum Parameter Ranges on Highly Preferred Images: Focus on Dynamic Range, Color, and Contrast (선호도 높은 이미지의 최적 파라미터 범위 연구: 다이내믹 레인지, 컬러, 콘트라스트를 중심으로)

  • Park, Hyung-Ju;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
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    • v.13 no.1
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    • pp.9-18
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    • 2013
  • In order to measure the parameters of consumers' preferred image quality, this research suggests image quality assessment factors; dynamic range, color, and contrast. They have both physical image quality factors and psychological characteristics from the previous researches. We found out the specific ranges of preferred image quality metrics. As a result, Digital Zone System meant for dynamic range generally shows 6~10 stop ranges in portrait, nightscape, and landscape. Total RGB mean values represent in portrait (67.2~215.2), nightscape (46~142), and landscape (52~185). Portrait total RGB averages have the widest range, landscape, and nightscape, respectively. Total scene contrast ranges show in portrait (196~589), nightscape (131~575), and landscape (104~767). Especially in portrait, skin tone RGB mean values are in ZONE V as the exposure standard, but practically image consumers' preferred skin tone level is in ZONE IV. Also, total scene versus main subject contrast ratio represents 1:1.2; therefore, we conclude that image consumers prefer the out-of-focus effect in portrait. Throughout this research, we can measure the preferred image quality metrics ranges. Also, we expect the practical and specific dynamic range, color, and contrast information of preferred image quality to positively influence product development.

Engineering Characteristics of the Light Weight Soil Using Phosphogypsum and EPS Beads (인산석고-EPS 조각을 활용한 경량혼합토의 공학적 특성)

  • Kim, Youngsang;Suh, Dongeun;Kim, Wonbong;Lee, Woobum
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.6
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    • pp.19-25
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    • 2009
  • The current study developed light-weighted mixed soil that can solve problems related with soft soil such as ground subsidence, sliding and lateral displacement of ground. By reducing weight of reclaimed soil through mixing phosphogypsum and recycled EPS beads with the weathered granite soil. A series of geotechnical laboratory tests including physical index test, compaction test, CBR test, and direct shear test were performed and engineering properties were reviewed in order to assess applicability of the light-weighted mixed soil for roads and abutment and various back-filling materials at the reclamation area. Based on the laboratory test results, it was found that the maximum dry unit weight of the light-weighted soil ranges $14.32{\sim}15.79kN/m^3$ and the optimum water content ranges 21.91~24.23%, which means there is 11~19.3% weight decrease effect when comparing with general weathered granite soil. Also it was found that the corrected CBR value ranges 10.4~18.4% satisfying the domestic regulations on road subgrade and back-filling material. In addition, as for shear strength parameter, cohesion ranges 10.79~18.64 kPa and internal frictional angle ranges $35.4{\sim}37.2^{\circ}$, which are similar with those of general construction soil and back-filling material used in Korea. So it can be concluded that light-weighted mixed soil with phosphogypsum can be used effectively for soft reclamation ground as actual filling material and back-filling material. From the current study, it was found that light-weighted mixed soil with phosphogypsum has not only weight reduction effect, but also has no special problems in shear strength and bearing capacity. Therefore, it is expected that phosphogypsum can be recycled in bulk as road subgrade and back-filling material at the reclamation area.

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Discrepancies between Calculated and Delivered Dose Distributions of Respiratory Gated IMRT Fields according to the Target Motion Ranges for Lung and Liver Cancer Patients (호흡연동방사선치료시 폐암과 간암환자의 병소 움직임 크기에 따른 선량분포 차이 분석)

  • Kim, Youngkuk;Lim, Sangwook;Choi, Ji Hoon;Ma, Sun Young;Jeung, Tae Sig;Ro, Tae Ik
    • Progress in Medical Physics
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    • v.25 no.4
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    • pp.242-247
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    • 2014
  • To see the discrepancies between the calculated and the delivered dose distribution of IMRT fields for respiratory-induced moving target according to the motion ranges. Four IMRT plans in which there are five fields, for lung and liver patients were selected. The gantry angles were set to $0^{\circ}$ for every field and recalculated using TPS (Eclipse Ver 8.1, Varian Medical Systems, Inc., USA). The ion-chamber array detector (MatriXX, IBA Dosimetry, Germany) was placed on the respiratory simulating platform and made it to move with ranges of 1, 2, and 3 cm, respectively. The IMRT fields were delivered to the detector with 30~70% gating windows. The comparison was performed by gamma index with tolerance of 3 mm and 3%. The average pass rate was 98.63% when there's no motion. When 1.0, 2.0, 3.0 cm motion ranges were simulated, the average pass rate were 98.59%, 97.82%, and 95.84%, respectively. Therefore, ITV margin should be increased or gating windows should be decreased for targets with large motion ranges.

Home-ranges of Female Pipistrellus abramus (Chiroptera: Vespertilionidae) in Different Reproductive Stages Revealed by Radio-telemetry (원격무선추적을 이용한 집박쥐 암컷의 번식단계에 따른 행동권 분석)

  • Chung, Chul-Un;Han, Sang-Hoon;Kim, Sung-Dae;Lim, Chun-Woo;Kim, Sung-Chul;Kim, Chul-Young;Lee, Hwa-Jin;Kwon, Yong-Ho;Kim, Young-Chae;Lee, Chong-Il
    • Korean Journal of Environment and Ecology
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    • v.25 no.1
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    • pp.1-9
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    • 2011
  • In order to analyze the change in home ranges depending on the reproductive stage of Pipistrellus abramus, radio-tracking was carried out for a total of 9 individuals, 3 individuals each, by dividing stages into a pregnancy stage, lactation stage, and post-lactation stage from May to August 2009. For radio-telemetry, 0.38g transmitters, R2000 receivers and 3-element Yagi antennas were used. Pipistrellus abramus were captured using a double-stacked mist net and a harp-trap. Analysis of home ranges used a SHP File and ArcGIS 3.3 for GIS, and used a Kernel Home Range Method(KHR) and a Minimum Convex Polygon(MCP) Method for analysis. Home ranges at the pregnancy stage were MCP 100% $13.46{\pm}1.84ha$, MCP 95% $12.28{\pm}2.15ha$, KHR 50% $3.00{\pm}0.71ha$, and home ranges at the lactation stage were MCP 100% $8.13{\pm}0.23ha$, MCP 95% $7.73{\pm}0.63ha$, KHR 50%$1.84{\pm}1.05ha$. Home ranges at the post-lactation stage were MCP 100% $125.58{\pm}97.77ha$, MCP 95% $123.89{\pm}97.73ha$, KHR 50% $28.61{\pm}26.78ha$. As a result, home ranges of pipistrellus abramus showed a significant difference in all of the MCP 100%, MCP 95%, KHR 50% depending on reproductive stages, being largest in the post-lactation stage and smallest in the lactation stage.