• Title/Summary/Keyword: peak

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On the UV Spectra of AcBr Lignins from Softwoods grown in Mt. Jiri (지리산산(智異山産) 침엽수재(針葉樹材) AcBr Lignin의 UV Spectra에 대(對)하여)

  • Jo, Jong-Soo;Moon, Chang-Kuck
    • Journal of the Korean Wood Science and Technology
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    • v.12 no.3
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    • pp.35-40
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    • 1984
  • The ultraviolet absorption spectra of AcBr lignin (Acetyl Bromide lignin) from 10 species grown in Mt. Jiri were determined. There were 3 peak positions, at 249nm (max peak), at 267-268 nm (shallow min. peak) and at 280 nm (lower max. peak). The Bjorkman lignin and lignin sulfonic acid spectra had shoulders, but the AcBr lignin had not them. Average absorbances and absorptivities of the AcBr lignins at peak positions were $0.367{\pm}0.0015$, $24.56{\pm}0.0535$, at 249 nm, $0.278{\pm}0.0016$, $18.50{\pm}0.0569$, at 267-268 nm and $0.306{\pm}0.0016$, $20.42{\pm}0.0627$ at 280 nm, respectively.

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Characteristics of Foot Pressure Distribution with or without Partial Prosthetic Foot in Transmetartarsal Amputee (경중족 절단 환자의 의족지 착용에 따른 족저압력 분포 특성)

  • Seong, Woo-Sung;Yang, Hee-Seung;Sung, Hong-Kee;Kim, Hak-Jun
    • Journal of Korean Foot and Ankle Society
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    • v.12 no.1
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    • pp.41-46
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    • 2008
  • Purpose: This study was designed to evaluate characteristics of foot pressure distribution with or without partial prosthetic foot in transmetatarsal amputee. Materials and Methods: The subjects were 9 transmetatarsal amputees. Foot pressures were measured at hallux, the $1^{st}-5^{th}$ metatarsal head (MTH), mid-foot, condyle area by F-scan system in amputated or contralateral foot during active walking. Results: In amputated foot, mean peak pressure was greatest in midfoot without prosthetic foot but it was greatest in hindfoot with prosthetic foot. In unaffected foot, although mean peak pressure was higher in hallux, and $1-5^{th}$ MTH compared to amputated foot, it was greatest in hind foot both with and without prosthetic foot. However, in unaffected foot, mean peak pressure significantly decreased in hallux and $5^{th}$ MTH after wearing the prosthetic foot. There was a significant difference in mean peak pressure in hallux and $5^{th}$ MTH between amputated and unaffected foot after wearing prosthetic foot. However, other region had no significant difference with or without prosthetic foot between feet. Conclusions: The use of partial prosthetic foot tends to shift weight bearing from the heel area to forefoot and could significantly reduce hind foot peak pressure and redistributed to peak pressure. The partial prosthetic foot can also offer the peak pressure to reduction both amputated foot and unaffected foot and help to toe off during walking.

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Special-Days Load Handling Method using Neural Networks and Regression Models (신경회로망과 회귀모형을 이용한 특수일 부하 처리 기법)

  • 고희석;이세훈;이충식
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.2
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    • pp.98-103
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    • 2002
  • In case of power demand forecasting, the most important problems are to deal with the load of special-days. Accordingly, this paper presents the method that forecasting long (the Lunar New Year, the Full Moon Festival) and short(the Planting Trees Day, the Memorial Day, etc) special-days peak load using neural networks and regression models. long and short special-days peak load forecast by neural networks models uses pattern conversion ratio and four-order orthogonal polynomials regression models. There are using that special-days peak load data during ten years(1985∼1994). In the result of special-days peak load forecasting, forecasting % error shows good results as about 1 ∼2[%] both neural networks models and four-order orthogonal polynomials regression models. Besides, from the result of analysis of adjusted coefficient of determination and F-test, the significance of the are convinced four-order orthogonal polynomials regression models. When the neural networks models are compared with the four-order orthogonal polynomials regression models at a view of the results of special-days peak load forecasting, the neural networks models which uses pattern conversion ratio are more effective on forecasting long special-days peak load. On the other hand, in case of forecasting short special-days peak load, both are valid.

Hydrological Studies on the Comparison and the Derivation of Unit Hydrography in the small River Systems. (소하천수계의 단위유량도 유도 및 비교에 관한 수문학적 고찰)

  • 이순혁
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.20 no.3
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    • pp.4739-4749
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    • 1978
  • This studies were conducted to derive synthetic unitgraphs and triangular unitgraphs correlated with watershed characteristics which can be used to the estimation and control of flood for the rational development of Agricultural water resources. Derived Synthetic unitgraphs and Triangular unitgraphs can be applied to the ungaged watersheds were compared with average unitgraphs by observed data. Seven small watersheds were selected as studying basins Han, Geum, Nakdong, Yeongsan and Inchon river system. The results summarized for these studies are as follows: 1. Average unitgraphs by observed data and dimensionless unitgraphs for synthesis were derived for all river systems. 2. Peak discharge per unit area of the unitgraph, qp, was derived as qp=10-0.389-0.0424Lg with a high significance. 3. Formulas for the base width of unitgraph of 50 and 75 percent for peak flow for each water systems was adopted as Table 5. 4. The base length of the unitgraph, Tb, in hours in connection with time to peak, Tp, in hours was expressed as Tb =4.3Tp. 5. Peak discharge, Qp, were obtained as Table 6 by the Triangular form to all subwatersheds. 6. Relative errors in the peak discharge of the synthetic unitgraphs showed to be 7.3 percent to the peak of observed average unitgraphs except errors of peak discharge for Yeongsan river system. This indicates that Synthetic unitgraphs for the small watersheds of Han, Geum, Nakdong and Inchon river systems can be applied to the ungaged watersheds. On the other hand, It was confirmed that the accuracy of Instantaneous Unit Hydrograph with only 1.6 percent as relative errors was approaching more closely to the observed average unitgraph than that of synthetic unitgraph with relative errors. 23.9 percent for Yeongsan river system. 7. Errors in the peak discharge of the triangular unitgraph to the observed average unitgraph showed to be 0.6 percent to 7.5 percent which can be regarded as a high precision within the range of 200 to 500$\textrm{km}^2$ in area. On the contrary, application of triangular unitgraph within the range of 200$\textrm{km}^2$ in area has defined as a unsuitable method because of high relative errors, 26.4 percent to 61.6 percent.

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Studies on the Active Materials of Alkaline Storage Battery. On Cadmium Electrode (알칼리 축전지의 활물질에 관한 연구. 카드뮴 전극에 관하여)

  • Ju Seong Lee;Choong Yeoul Joo;Park, Su Gil
    • Journal of the Korean Chemical Society
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    • v.25 no.5
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    • pp.325-330
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    • 1981
  • The electrochemical behavior of cadmium electrode for the nickel-cadmium battery system has been studied by cyclic voltammetry, controlled potential electrolysis and X-ray diffraction method. Cathodic polarization curve for cadmium hydroxide electrode prepared by electrochemical pretreatment of metallic cadmium showed two peaks. It has been found that cadmium hydroxide was reduced to cadmium metal at the first peak potential, whereas very activated metal of cadmium which was strongly oriented (002) rather than (101) was formed at the second peak potential. It was also found that the cadmium formed at the second peak potential reacted rapidly with oxygen. Therefore, it could be presumed that the cadmium recombination reaction with the oxygen was chemical, and could be represented as $2Cd + O_2 + 2H_2O\;{\longrightarrow}\;2Cd(OH)_2$.

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The Effect of Change in Gait Speed on Vertical Force of the Cane and Distribution of Affected Foot in the Persons with Chronic Stroke (보행속도의 변화가 만성 뇌졸중 환자 지팡이의 수직력과 마비측 발의 체중지지에 미치는 영향)

  • Jung, Kyoung-Sim;Seo, Hyun-Du;Lee, Kwan-Woo;Chung, Yi-Jung
    • Journal of the Korean Society of Physical Medicine
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    • v.7 no.2
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    • pp.223-230
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    • 2012
  • Purpose : The purpose of this study was to analyze weight bearing of cane and affected foot at different speeds during walking. Methods : Thirteen subjects (6 males, 7 females) with stroke enrolled in the study. A foot sensor and an instrumented cane were integrated to analyze the vertical peak force on the affected foot and the cane. Results : The applied vertical peak force on the cane were $12.02{\pm}4.80%$ (slow speed), $7.97{\pm}3.95%$ (comfortable speed), and $6.86{\pm}3.30%$ (fast speed) body weight, respectively. The results indicated significantly lower vertical peak force on the affected foot in the low speed walking condition when compared to the fast walking (p<.05) and the comfortable walking (p<.05) conditions. The correlations between TUG and vertical peak force on the cane and affected foot were .71, and -.70 (p<.01). There was a higher correlation between the vertical peak force on the cane and affected foot were -.87(p<.01). Conclusion : In conclusion, slower walking speed applied greater vertical peak force on the cane. On the contray, slower walking speed applied less vertical peak force on the affected foot. Further studies, duration of force should be measured at different speeds during walking in lower and higher functioning hemiparetic subjects, as its use may mask underlying gait impairment.

Peak seismic response of a symmetric base-isolated steel building: near vs. far fault excitations and varying incident angle

  • Pavlidou, Constantina;Komodromos, Petros
    • Earthquakes and Structures
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    • v.18 no.3
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    • pp.349-365
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    • 2020
  • Since the peak seismic response of a base-isolated building strongly depends on the characteristics of the imposed seismic ground motion, the behavior of a base-isolated building under different seismic ground motions is studied, in order to better assess their effects on its peak seismic response. Specifically, the behavior of a typical steel building is examined as base-isolated with elastomeric bearings, while the effect of near-fault ground motions is studied by imposing 7 pairs of near- and 7 pairs of far-fault seismic records, from the same 7 earthquake events, to the building, under 3 different loading combinations, through three-dimensional (3D) nonlinear dynamic analyses, conducted with SAP2000. The results indicate that near-fault seismic components are more likely to increase the building's peak seismic response than the corresponding far-fault components. Furthermore, the direction of the imposed earthquake excitations is also varied by rotating the imposed pairs of seismic records from 0◦ to 360◦, with respect to the major construction axes. It is observed that the peak seismic responses along the critical incident angles, which in general differ from the major horizontal construction axes of the building, are significantly higher. Moreover, the influence of 5% and 10% accidental mass eccentricities is also studied, revealing that when considering accidental mass eccentricities the peak relative displacements of the base isolated building at the isolation level are substantially increased, while the peak floor accelerations and interstory drifts of its superstructure are only slightly affected.

The Characteristics of Shoulder Muscles in Archery Athletes

  • Kim, Ri Na;Lee, Jin-Hyuck;Hong, Seok Ha;Jeon, Jin Ho;Jeong, Woong Kyo
    • Clinics in Shoulder and Elbow
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    • v.21 no.3
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    • pp.145-150
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    • 2018
  • Background: This study evaluated the shoulder girdle muscle characteristics of elite archery athletes and provides suggestions for archery training programs. Methods: This study enrolled 15 cases of high level archery athletes (7 males, 8 females) and 30 cases of (15 males, 15 females) sex, age-matched, healthy, non-athletic individuals. We measured peak torques of flexion (FL), extension (EX), abduction (ABD), adduction (ADD), external rotation (ER) and internal rotation (IR) of both shoulders at an angular velocity of $30^{\circ}/sec$, $60^{\circ}/sec$, and $180^{\circ}/sec$. The peak torques and peak torque ratios of FL/EX, ABD/ADD, and ER/IR of the two groups were compared. Results: The archer group had a greater peak torque of IR and ADD, but only in the left shoulder (p<0.05). In the same group, both shoulders had greater peak torque of EX and lower peak torque of FL. The peak torque ratios of FL/EX of both shoulders were significantly lower in the archer group at all three angular velocities (p<0.05). The peak torque ratios of ABD/ADD were significantly greater in only the left shoulder of the archer group (p<0.05). Conclusions: The prominent characteristics of the shoulder girdle muscles of an elite archer are stronger adductor muscles of the bow shoulder and stronger extensors of both shoulders, as compared to healthy, non-athletic individuals. These muscle groups of the shoulder probably contribute a major role in maintaining the accuracy and stability during archery shooting. Hence, a training program that selectively enhances the adductor and extensor muscles could prove helpful in enhancing the archery skills of the athlete.

Effect of irrigation reservoir, antecedent soil moisture condition and Huff time distribution on peak discharge in a basin (농업용 저수지, 선행토양함수조건 및 Huff 시간 분포가 유역의 첨두홍수량에 미치는 영향 분석)

  • Kwon, Minsung;Ahn, Jae-Hyun;Jun, Kyung Soo;Kim, Tae-Woong
    • Journal of Korea Water Resources Association
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    • v.51 no.5
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    • pp.417-424
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    • 2018
  • This study analyzed the effect of irrigation reservoirs, antecedent soil moisture conditions (AMC) and Huff time distribution on peak discharge using Monte Carlo simulation. The peak discharge was estimated for four different cases in combination of irrigation reservoir capacity, AMC, and Huff time distribution. Applying 100% reservoir capacity or AMC-III, the peak discharges corresponding return periods of 50~300 years were overestimated by 25~30% compared to those of cases that considered the probability of occurrence for individual condition. Applying the 3rd quantile huff distribution, the peak discharges were overestimated by 5% over the peak discharge that considered the probability of occurrence. The overall results indicated that the effect on the peak flood of Huff distribution was less than AMC and reservoir storage.

Circuit Design of Parallel Power Operation Equipment for Peak Power Reduction (상전원의 피크치 전력 감소를 위한 전력병합장치 회로설계)

  • Yang, Jaesoo;Kim, Donghan;Kim, ManDo
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.9
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    • pp.273-278
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    • 2014
  • Recent use of electricity during peak hours electricity supply-demand imbalance is inevitable that limit power use force. Therefore, in this paper, a circuit of parallel power operation equipment for peak power reduction which saves the power to electricity storage device during the non-peak power time and supply from the storage power during the expected power shortages time is designed Through this circuitry, the peak power of the commercial power supply with the parallel operation and connection of the commercial power supply and the power supply of the inverter from electricity storage that is a key feature of PRS(Peak power Reduction System) can be controlled. In addition, in order to increase the efficiency, a Transless Power Circuit DC-AC inverter is developed. Moreover, a variable impedance control is applied to the storage of electric power of an Uninterruptible Power Supply associated with a commercial power source.