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Biomechanical Effectiveness of the Low-Dye Taping on Peak Plantar Pressure During Treadmill Walking Exercise in Subjects With Flexible Flatfoot

  • Lim, One-Bin;Kim, Jeong-Ah;Kwon, Oh-Yun;Yi, Chung-Hwi
    • Physical Therapy Korea
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    • v.22 no.2
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    • pp.41-51
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    • 2015
  • The purposes of this study were 1) to determine the effects of low-dye taping on peak plantar pressure following treadmill walking exercise, 2) to determine whether the biomechanical effectiveness of low-dye taping in peak plantar pressure was still maintained following removal of the tape during treadmill walking, and 3) to determine the trend towards a medial-to-lateral shift in peak plantar pressure in the midfoot region before and after application of low-dye taping. Twenty subjects with flexible flatfoot were recruited using a navicular drop test. The peak plantar pressure data were recorded during five treadmill walking sessions: (1) un-taped, (2) baseline-taped, (3) after a 10-minute treadmill walking exercise, (4) after a 20-minute treadmill walking exercise, and (5) after removal of the taping. The foot was divided into six parts during the data analysis. One-way repeated measures analysis of variance was performed to investigate peak plantar pressure variations in the six foot parts in the five sessions. This study resulted in significantly increased medial forefoot peak plantar pressure compared to the un-taped condition (p=.017, post 10-minute treadmill walking exercise) and (p=.021, post 20-minute treadmill walking exercise). The peak plantar pressure in the lateral forefoot showed that there was a significant decrease after sessions of baseline-taped (p=.006) and 10-minute of treadmill walking exercise (p=.46) compared to the un-taped condition. The tape removal values were similar to the un-taped values in the five sessions. Thus, the findings of the current study may be helpful when researchers and clinicians estimate single taping effects or consider how frequently taping should be replaced for therapeutic purposes. Further studies are required to investigate the evidence in support of biomechanical effectiveness of low-dye taping in the midfoot region.

Theoretical considerations on the giant magnetoimpedance effect in amorphous ribbons

  • Phan, Manh-Huong;Nguyen Cuong;Yu, Seong-Cho
    • Proceedings of the Korean Magnestics Society Conference
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    • 2003.06a
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    • pp.60-61
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    • 2003
  • Theoretical considerations on a giant magneto-impedance (GMI) effect in amorphous ribbons (i.e., thin films) have been made in terms of the expressions of effective permeability and impedance derived in the frame of classical electrodynamics and ferromagnetism. The dependence of GMI effect on the external do magnetic field (H$\_$ext/) and the frequency of alternating current are simulated and discussed in the knowledge of energy conversion consisting of the current energy loss, the ferromagnetic energy consumption, and the magnetic energy storage in the film. The obtained results are summarized as follow: (a) As frequency f< 20 ㎒, the real part of effective permeability (${\mu}$′) changes slightly. The peak of the ${\mu}$′curve always locates at H$\_$ext/=H$\_$ani/ - the anisotropy field. However, the peak value of ${\mu}$′ tends to increase with increasing frequency in the frequency range of 11-20 ㎒. (b) In the frequency range, f= 21-23 ㎒, a negative peak additionally appears. Meanwhile, both the positive and negative peak values rapidly increase with increasing frequency and their peak positions shift towards a high H$\_$ext/. (c) The positive peak value of ${\mu}$′ starts to decrease at f= 29 ㎒ and its negative peak does so at about 35 ㎒. Then, both peaks keep such a tendency and their peak positions move to high H$\_$ext/, as increasing frequency. (d) The dependence of the imaginary part of effective permeability (${\mu}$") on the external dc magnetic field and the frequency of the alternating field indicates that there is only one peak involved in ${\mu}$" for the whole frequency range. (e) The impedance vs. magnetic field curves at various frequencies show that there is a critical value of frequency around f= 18-19 ㎒ where the transition between two frequency regimes occurs; the one (low frequency) in which ${\mu}$′ predominantly contributes to the GMI effect and the other (high frequency) in which ${\mu}$" determines the GMI effect.

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Generation of Daily Load Curves for Performance Improvement of Power System Peak-Shaving (전력계통 Peak-Shaving 성능향상을 위한 1일 부하곡선 생성)

  • Son, Subin;Song, Hwachang
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.2
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    • pp.141-146
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    • 2014
  • This paper suggests a way of generating one-day load curves for performance improvement of peak shaving in a power system. This Peak Shaving algorithm is a long-term scheduling algorithm of PMS (Power Management System) for BESS (Battery Energy Storage System). The main purpose of a PMS is to manage the input and output power from battery modules placed in a power system. Generally, when a Peak Shaving algorithm is used, a difference occurs between predict load curves and real load curves. This paper suggests a way of minimizing the difference by making predict load curves that consider weekly normalization and seasonal load characteristics for smooth energy charging and discharging.

A study on the Management of Non-point Source Using Peak Water Quality Concentration (첨두수질농도를 이용한 비점오염원 관리방안 연구)

  • Kal, Byungseok;Park, Jaebeom;Kwon, Heongak;Im, Taehyo;Lee, Jiho
    • Journal of Wetlands Research
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    • v.19 no.3
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    • pp.287-295
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    • 2017
  • In this study, rainfall runoff characteristics according to peak concentration were analyzed using the water quality and flow data in the Geumho river, and the direction of nonpoint source management such as monitoring and management period by pollution source was derived. Peak Water Quality Concentration is the concept that utilizes the extreme value as the concentration of non-point pollution control standard with the highest water quality in the rainwater runoff. Using this method, the evaluation factors such as cumulative precipitation(total precipitation), peak water quality concentration, cumulative precipitation up to peak water quality concentration, time to peak water quality concentration, and EMC to peak water quality concentration were examined and long- Rainfall runoff characteristics of nonpoint sources were analyzed. The results of the analysis suggested proper monitoring and management method to manage nonpoint source.

Studies on the Activity of Glutamine Synthetase(GSA) in Wheat Leaves I. Variation of GSA by Different Leaf Position and its Depression Phenomenon after Inflorescence Emerged (소맥겹의 Glutamine Synthetase 활성도에 관한 연구 I. 엽위별 GS활성도의 차이 및 출수후 "V"자형 변화현상)

  • 손상목
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.1
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    • pp.98-105
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    • 1989
  • The examination to find out how the activity of glutamine synthetase (GSA) develop in each wheat leaves during the growth period was carried out. GSA/g FW/leaf were very low at leaf differentiation stage and increased highly several times by unfolding and development of leaf, and declined deeply with the advance of senescence in each leaves. GSA/g FW/leaf were risen gradually from the every lower leaves to the every upper leaves, in consequence activity level and maximum peak per g fresh weight of 7th-flag leaves were two or three times higher than those at the 1st-4th leaves in all of 12 applied nitrogen treatments, thereupon. the highest activities per g fresh weight showed in the 8th leaves. GSA/g FW/leaf was shown two peaks in the 6th-flag leaves and one peak in 1st-4th leaves, respectively. GSA/g FW/leaf (except for senescence leaves) and GSA/plant were increased gradually to the infloresscence emerging stage and were shown the first maximum peak at 13 days before anthesis, then were declined rapidly. to the milk ripe stage (7 days after anthesis). and were shown the second maximum peak at the early dough ripe stage (22 days after anthesis) .

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Effect of roughness on interface shear behavior of sand with steel and concrete surface

  • Samanta, Manojit;Punetha, Piyush;Sharma, Mahesh
    • Geomechanics and Engineering
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    • v.14 no.4
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    • pp.387-398
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    • 2018
  • The present study evaluates the interface shear strength between sand and different construction materials, namely steel and concrete, using direct shear test apparatus. The influence of surface roughness, mean size of sand particles, relative density of sand and size of the direct shear box on the interface shear behavior of sand with steel and concrete has been investigated. Test results show that the surface roughness of the construction materials significantly influences the interface shear strength. The peak and residual interface friction angles increase rapidly up to a particular value of surface roughness (critical surface roughness), beyond which the effect becomes negligible. At critical surface roughness, the peak and residual friction angles of the interfaces are 85-92% of the peak and residual internal friction angles of the sand. The particle size of sand (for morphologically identical sands) significantly influences the value of critical surface roughness. For the different roughness considered in the present study, both the peak and residual interaction coefficients lie in the range of 0.3-1. Moreover, the peak and residual interaction coefficients for all the interfaces considered are nearly identical, irrespective of the size of the direct shear box. The constitutive modeling of different interfaces followed the experimental investigation and it successfully predicted the pre-peak, peak and post peak interface shear response with reasonable accuracy. Moreover, the predicted stress-displacement relationship of different interfaces is in good agreement with the experimental results. The findings of the present study may also be applicable to other non-yielding interfaces having a similar range of roughness and sand properties.

Power Optimization Method Using Peak Current Modeling for NAND Flash-based Storage Devices (낸드 플래시 기반 저장장치의 피크 전류 모델링을 이용한 전력 최적화 기법 연구)

  • Won, Samkyu;Chung, Eui-Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.1
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    • pp.43-50
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    • 2016
  • NAND flash based storage devices adopts multi-channel and multi-way architecture to improve performance using parallel operation of multiple NAND devices. However, multiple NAND devices consume higher current and peak power overlap problem influences on the system stability and data reliability. In this paper, current waveform is measured for erase, program and read operations, peak current and model is defined by profiling method, and estimated probability of peak current overlap among NAND devices. Also, system level TLM simulator is developed to analyze peak overlap phenomenon depending on various simulation scenario. In order to remove peak overlapping, token-ring based simple power management method is applied in the simulation experiments. The optimal peak overlap ratio is proposed to minimize performance degradation based on relationship between peak current overlapping and system performance.

Fuzzy LP Based Power Network Peak Shaving Algorithm (퍼지 LP 기반 전력망 Peak Shaving 알고리즘)

  • Ohn, Sungmin;Kim, Jung-Su;Song, Hwachang;Chang, Byunghoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.6
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    • pp.754-760
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    • 2012
  • This paper describes peak shaving algorithms as long-term cycle scheduling in the power management system (PMS) for MW-scale battery energy storage systems (BESS). The purpose of PMS is basically to manage the input and output power from battery modules placed in the systems. Assuming that an one-day ahead load curve is provided, off-line peak shaving algorithms can be employed, but applying the results of the off-line algorithm may result in the difference in the real-time performance because there is uncertainty in the provided load curve. This paper adopts fuzzy based LP (linear programming) algorithms for describing the peak shaving algorithm in PMS and discusses a solution technique and real-time operation strategies using the solution.

Improvement of Peak Cough Flow After the Application of a Mechanical In-exsufflator in Patients With Neuromuscular Disease and Pneumonia: A Pilot Study

  • Jung, Ji Ho;Oh, Hyeon Jun;Lee, Jang Woo;Suh, Mi Ri;Park, Jihyun;Choi, Won Ah;Kang, Seong-Woong
    • Annals of Rehabilitation Medicine
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    • v.42 no.6
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    • pp.833-837
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    • 2018
  • Objective To investigate and demonstrate persistent increase of peak cough flow after mechanical in-exsufflator application, in patients with neuromuscular diseases and pneumonia. Methods A mechanical in-exsufflator was applied with patients in an upright or semi-upright sitting position (pressure setting, +40 and $-40cmH_2O$; in-exsufflation times, 2-3 and 1-2 seconds, respectively). Patients underwent five cycles, with 20-30 second intervals to prevent hyperventilation. Peak cough flow without and with assistive maneuvers, was evaluated before, and 15 and 45 minutes after mechanical in-exsufflator application. Results Peak cough flow was 92.6 L/min at baseline, and 100.4 and 100.7 L/min at 15 and 45 minutes after mechanical in-exsufflator application, respectively. Assisted peak cough flow at baseline, 15 minutes, and 45 minutes after mechanical in-exsufflator application was 170.7, 179.3, and 184.1 L/min, respectively. While peak cough flow and assisted peak cough flow increased significantly at 15 minutes after mechanical in-exsufflator application compared with baseline (p=0.030 and p=0.016), no statistical difference was observed between 15 and 45 minutes. Conclusion Increased peak cough flow after mechanical in-exsufflator application persists for at least 45 minutes.

Grid Peak Power Limiting / Compensation Power Circuit for Power Unit under Dynamic Load Profile Conditions (Dynamic Load Profile 조건의 전원 장치에 있어서 계통 Peak Power 제한/보상 전력 회로)

  • Jeong, Hee-Seong;Park, Do-Il;Lee, Yong-Hwi;Lee, Chang-Hyeon;Rho, Chung-Wook
    • The Transactions of the Korean Institute of Power Electronics
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    • v.27 no.5
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    • pp.376-383
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    • 2022
  • The improved performance of computer parts, such as graphic card, CPU, and main board, has led to the need for power supplies with a high power output. The dynamic load profile rapidly changes the usage of power consumption depending on load operations, such as PC power and air conditioner. Under dynamic load profile conditions, power consumption can be classified into maximum, normal, and standby power. Several problems arise in the case of maximum power. Peak power is generated at the system power source in the maximum-power situation. Frequent generation of peak power can cause high-frequency problems and reduce the life of high-pressure parts (especially high-pressure capacitors). For example, when a plurality of PCs are used, system overload occurs due to peak power generation and causes problems, such as power failure and increase in electricity bills due to exceeded contract power. To solve this problem, a system peak power limit/compensation power circuit is proposed for a power supply under dynamic load profile conditions. The proposed circuit detects the system current to determine the power situation of the load. When the system current is higher than the set level, the circuit recognizes that the system current generates peak power and compensates for the load power through a converter using a super capacitor as the power source. Thus, the peak power of loads with a dynamic load profile is limited and compensated for, and problems, such as high-frequency issues, are solved. In addition, the life of high-pressure parts is increased.