• Title/Summary/Keyword: gravity reduction

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Diagnosis and Management of Suspected Deltoid Injury (삼각인대 손상 의심 시 진단과 치료방법)

  • Yang, Sung Hun;Lee, Jun Young
    • Journal of Korean Foot and Ankle Society
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    • v.26 no.1
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    • pp.16-21
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    • 2022
  • When an ankle lateral malleolar fracture is accompanied by a deltoid ligament rupture without a medial malleolar fracture, such an injury is called a bimalleolar equivalent fracture. This means that even if there is no bony injury on the medial side, there may be functional instability of the ankle joint due to damage to the deltoid ligament. Manual or gravity external rotational stress radiography is used to differentiate an ankle bimalleolar equivalent fracture from an isolated lateral malleolar fracture. If the medial joint gap is widened on the stress radiography, the deltoid ligament injury can be diagnosed, and surgical treatment for fibula fractures is recommended. After open reduction of the fibula fracture (with syndesmotic fixation if needed), a decision on the repair of the deltoid ligament is taken depending on the surgeons' preference and intraoperative findings. The deltoid ligament repair is performed by inserting a suture anchor (or anchors) in the medial malleolus and fixing the deep and superficial deltoid ligaments to the medial malleolus. The only randomized study to evaluate the utility of deltoid ligament sutures in ankle fractures did not support the deltoid ligament suture, but the study itself had many limitations. An appropriately powered, randomized, controlled trial of the deltoid ligament repair with both patient-reported outcome and radiographic outcome evaluation is needed in the future.

Rapid assessment of suspension bridge deformation under concentrated live load considering main beam stiffness: An analytical method

  • Wen-ming Zhang;Jia-qi Chang;Xing-hang Shen;Xiao-fan Lu;Tian-cheng Liu
    • Structural Engineering and Mechanics
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    • v.88 no.1
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    • pp.53-65
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    • 2023
  • With the gradual implementation of long-span suspension bridges into high-speed railway operations, the main beam's bending stiffness contribution to the live load response permanently grows. Since another critical control parameter of railway suspension bridges is the beam-end rotation angle, it should not be ignored by treating the main beam deflection as the only deformation response. To this end, the current study refines the existing method of the main cable shape and simply supported beam bending moment analogy. The bending stiffness of the main beam is considered, and the main beam's analytical expressions of deflection and rotation angle in the whole span are obtained using the cable-beam deformation coordination relationship. Taking a railway suspension bridge as an example, the effectiveness and accuracy of the proposed analytical method are verified by the finite element method (FEM). Comparison of the results by FEM and the analytical method ignoring the main beam stiffness revealed that the bending stiffness of the main beam strongly contributed to the live load response. Under the same live load, as the main beam stiffness increases, the overall deformation of the structure decreases, and the reduction is particularly noticeable at locations with original larger deformations. When the main beam stiffness is increased to a certain extent, the stiffening effect is no longer pronounced.

A Unicode based Deep Handwritten Character Recognition model for Telugu to English Language Translation

  • BV Subba Rao;J. Nageswara Rao;Bandi Vamsi;Venkata Nagaraju Thatha;Katta Subba Rao
    • International Journal of Computer Science & Network Security
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    • v.24 no.2
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    • pp.101-112
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    • 2024
  • Telugu language is considered as fourth most used language in India especially in the regions of Andhra Pradesh, Telangana, Karnataka etc. In international recognized countries also, Telugu is widely growing spoken language. This language comprises of different dependent and independent vowels, consonants and digits. In this aspect, the enhancement of Telugu Handwritten Character Recognition (HCR) has not been propagated. HCR is a neural network technique of converting a documented image to edited text one which can be used for many other applications. This reduces time and effort without starting over from the beginning every time. In this work, a Unicode based Handwritten Character Recognition(U-HCR) is developed for translating the handwritten Telugu characters into English language. With the use of Centre of Gravity (CG) in our model we can easily divide a compound character into individual character with the help of Unicode values. For training this model, we have used both online and offline Telugu character datasets. To extract the features in the scanned image we used convolutional neural network along with Machine Learning classifiers like Random Forest and Support Vector Machine. Stochastic Gradient Descent (SGD), Root Mean Square Propagation (RMS-P) and Adaptative Moment Estimation (ADAM)optimizers are used in this work to enhance the performance of U-HCR and to reduce the loss function value. This loss value reduction can be possible with optimizers by using CNN. In both online and offline datasets, proposed model showed promising results by maintaining the accuracies with 90.28% for SGD, 96.97% for RMS-P and 93.57% for ADAM respectively.

Effects of Temperature and Water Pressure on the Material Properties of Granite & Limestone from Gagok Mine (온도와 수압이 가곡광산 화강암과 석회암의 물성에 미치는 영향)

  • Yoon, Yong-Kyun;Baek, Young-Jun;Jo, Young-Do
    • Tunnel and Underground Space
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    • v.21 no.1
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    • pp.33-40
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    • 2011
  • This study focuses on having a temperature and water pressure effects on the change of material properties of rocks. Granite and limestone specimens from Gagok Mine were thermally treated with predetermined temperatures of 200, 300, 400, 500, 600 and $700^{\circ}C$ (excepting $700^{\circ}C$ for limestone) to estimate the reduction of material properties of rocks caused by heat. Specific gravity, effective porosity, elastic wave velocity, uniaxial compressive strength, Young's modulus and Poisson's ratio for pre-heated specimens were measured. With increasing temperature, material properties of both rock specimens change sequentially. Significant changes of specific gravity, effective porosity and elastic wave porosity occur above $400^{\circ}C$ for granite and $300^{\circ}C$ for limestone. Changes of uniaxial compressive strength, Young's modulus and Poisson's ratio seem to be similar to those of physical properties. GSI of 500, 600 and $700^{\circ}C$ specimens inferred by using uniaxial compressive strength and Young's modulus of preheated granite specimens is found to be 81, 66 and 58 each. In case of pre-heated limestone specimens of 400, 500 and $600^{\circ}C$, the corresponding GSI is 76, 71 and 65 each. 500, 600 and $700^{\circ}C$ granite specimens and 400, 500 and $600^{\circ}C$ limestone specimens were pressurized to 7.5 MPa and their effective porosity, elastic wave velocity, uniaxial compressive strength and Young's modulus were measured. The average value of material properties (mentioned above) of 500, 600 and $700^{\circ}C$ granite specimens under water pressure compared with material properties of non-pressurized pre-heated specimens exhibits the reduction of 7.6, 11.3 and 14.9%, respectively. In case of 400, 500 and $600^{\circ}C$ limestone specimens under water pressure, the average value of material properties decreases by 8.2, 13.8 and 21.9%, respectively.

Analysis of Membrane Fouling Reduction by Natural Convection Instability Flow in Membrane Filtration of Colloidal Solution: Application of Blocking Filtration Model (콜로이드 용액의 막여과에서 자연대류 불안정 흐름의 막오염 저감 효과 해석: 막힘여과 모델의 적용)

  • Kim, Ye-Ji;Youm, Kyung-Ho
    • Membrane Journal
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    • v.29 no.6
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    • pp.329-338
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    • 2019
  • The constant-pressure and constant-flux membrane filtration experiments of alumina colloidal solution are performed to investigate defouling effect of the natural convection instability flow (NCIF) induced in membrane module. The permeate flux at constant-pressure and the transmembrane pressure (TMP) at constant-flux experiments are measured by changes the inclined angle (0, 90 and 180°) of membrane module to the gravity, and flux results are analyzed by using the blocking filtration model. NCIF are more induced as the inclined angles increased from 0° to 180°, and the maximum induced NCIF at 180° angle enhances flux to 2.8 times and reduces TMP to 85% after two-hour operation. As a result of analyzing flux data by applying the blocking filtration model, it is more reasonable to analyze them by using the intermediate blocking model within 15-minute operation time and then thereafter times by using the cake filtration model. The induced NCIF at 180° angle reduces the intermediate blocking fouling at 52% in the early operation time of 15-minute and thereafter the cake layer fouling at 93%. The main membrane fouling control mechanism of NCIF induced in membrane module is evaluated as suppressing the formation of the cake layer of particulate colloidal materials on membrane surface.

Organic Matter and Hydraulic Loading Effects on Nitrification Performance in Fixed Film Biofilters with Different Filter Media

  • Peng, Lei;Oh, Sung-Yong;Jo, Jae-Yoon
    • Ocean and Polar Research
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    • v.25 no.3
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    • pp.277-286
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    • 2003
  • Nitrification performance of fixed film biofilters using coarse sand, loess bead, or styrofoam beads in biofilter columns 1 meter high and 30cm in diameter were studied at different hydraulic and organic matter loading rates. Synthetic wastewater was supplied to the culture tank in order to maintain desired TAN concentrations in inlet water to biofilters. All the biofilters were conditioned 5 months before start of sampling. TAN and $NO_2-N$ conversion rates increased with an increase in the hydraulic loading rate (HLR). However, the improvement in biofilter performance was not linearly correlated to HLR in styrofoam bead filters. This is mainly due to the characteristics of the styrofoam beads used. TAN conversion rates of sand filters increased with the increase of HLR up to $200m^3/m^2$. per day. No increase in the TAN conversion rate was observed at the highest HLR since flooding on the media surface took place. HLR had a significant impact on the TAN conversion rates in loess bead filter up to the highest HLR tested (P<0.05). TAN conversion rates were much less at organic matter loading rates of 9 and 18kg $O_2/m^3$ per day than those without the addition of organic matter in styrofoam bead filters. The addition of glucose resulted in a reduction of the TAN conversion rate from 540 to 284g $TAN/m^3$ per day. No significant difference of TAN conversion rates between the two organic matter loading rates was found (p<0.05). This indicates that the impact of organic matter on nitrification becomes less and less sensitive with an increase in the COD/TAN ratio. At an organic matter loading rate of 9kg $O_2/m^3$. per day, a great reduction of TAN conversion rates was observed in sand filters and loess bead filters. Clearly, organic matter can be one of the most Important Impacting factors on nitrification. $NO_2-N$ conversion rates showed a similar trend for TAN. Based on the TAN and nitrite conversion rates, styrofoam beads showed the best performance among the three filter media tested. Also, the low gravity and price of styrofoam beads make the handling easier and more cost-effective for commercial application. The results obtained at the highest organic matter loading rates can be used in the biofilter design in recirculating aquaculture system.

Effects of Strawberry Powders on the Quality Characteristics of Yellow Layer Cake (딸기 분말의 첨가가 옐로우 레이어 케이크의 품질특성에 미치는 영향)

  • Kim, Yeoung-Ae
    • Korean journal of food and cookery science
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    • v.24 no.4
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    • pp.536-541
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    • 2008
  • In order to determine the effects of strawberry powder on the baking quality of cakes, yellow layer cakes were prepared with four freeze-dried strawberry powders substitutes, at levels of 0%, 1%, 2%, 3%, 4% and 5%. Then, the physical properties, baking properties and sensory characteristics of the finished cakes were assessed. The cakes were stored for 6 days at $22^{\circ}C$ and the change in hardness during storage was evaluated. The Viscosity of the doughs, as well as the specific gravity, increased as the amount of strawberry powder in the flour increased. The volume indices of the strawberry powder cakes were less than that of control, but the other indices did not differ from those of the controls. The crust color of the strawberry cakes evidenced a reduction in L. a and b values. The crumb color also evidenced a reduction in the L and b values, but the a values increased. Sensory characteristics were evaluated by 60 students from the Dept. of Food and Biotechnology. Crust color, crumb color, moistness, softness, taste and overall acceptance were measured via a 5-scale acceptance test. The crust color of cakes containing more than 3% strawberry powders and the crumb color of all strawberry cakes evidenced lower scores than the controls. Cakes containing 5% strawberry powders were least acceptable in terms of overall characteristics. Although cakes prepared with flour containing up to 4% strawberry powder were less acceptable than the controls, general sensory scores ranged in an average${\sim}$like range. The incorporation of strawberry power into cakes was shown to increase the overall hardness.

Improved Design of Hydraulic Circuit of Front-end Loader for Bump Shock Reduction of an Agricultural Tractor (농업용 트랙터의 프론트 로더 충격 저감을 위한 유압 회로의 설계 개선)

  • Cho, Bong Jin;Ahn, Seong Wook;Lee, Chang Joo;Yoon, Young Hwan;Lee, Soo Seong;Kim, Hak Jin
    • Journal of Drive and Control
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    • v.13 no.2
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    • pp.10-18
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    • 2016
  • A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements to mechanize routine agricultural tasks. When the FEL is used with a loaded bucket, careful operation is required to maintain safety and avoid spillage when the tractor passes a bump because a change in the gravity center of the tractor due to varied loadings can affect the stability of the tractor. Use of a boom suspension system consisting of accumulators and orifice dampers can be instrumental in reducing pitching vibrations while increasing the handling performance of the FEL-mounted tractor. The objective of this research was to reduce bump shocks by adding an orifice and a flow control valve to the original hydraulic circuit composed solely of accumulators. A simulation study was performed using the SimulationX program to investigate the effects of an accumulator and an orifice-throttle damper on bump shocks. Results showed that the peak pressure on a boom cylinder and the vertical acceleration of a bucket were significantly affected by use of both an accumulator and an orifice damper. In a field test conducted with a 75-kW tractor, the peak pressure of the boom cylinder, and the root mean square (RMS) vertical acceleration of the bucket and seat were reduced by on average, 23.0, 42.2, and 44.9% respectively, as compared to those measured with the original accumulator system, showing that an improved design for the accumulator hydraulic circuit can reduce bump shocks. Further studies are needed to design a tractor suspension system that includes the effects of cabin suspension and tires as well as dynamic analysis.

Analysis of Membrane Fouling Reduction by Natural Convection Instability Flow in Membrane Filtration of Protein Solution Using Blocking Filtration Model (막힘여과 모델에 의한 단백질 용액의 막여과에서 자연대류 불안정 흐름의 막오염 제어 효과 해석)

  • Kim, Ye-Ji;Youm, Kyung-Ho
    • Membrane Journal
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    • v.29 no.1
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    • pp.18-29
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    • 2019
  • The dead-end ultrafiltration (UF) of BSA protein solution was performed to investigate the defouling effects of natural convection instability flow (NCIF) induced in membrane module. The permeate fluxes were measured according to the inclined angles ($0{\sim}180^{\circ}$) of membrane module with respect to gravity, and analyzed using the blocking filtration model. NCIF are more induced as the inclined angles increased from $0^{\circ}$ to $180^{\circ}$, and the induced NCIF enhances flux. Comparing the fluxes at $0^{\circ}$ inclined angle (no NCIF induction) and $180^{\circ}$ (maximum NCIF induction), the flux enhancements by NCIF induction are increased about 5 times in the short-term UF operation (2 hours) and about 17 times in the long-term operation (20 hours). As applying the blocking filtration model, it is more suitable to analyze the flux results by using the intermediate blocking model in the early times of UF operation within 15 minutes and then thereafter times by using the cake filtration model. NCIF induced at $180^{\circ}$ inclined angle reduces the intermediate blocking fouling at about 67% in the early times operation and thereafter the cake layer fouling at about 99.9%. The main defouling mechanism of NCIF induced in the membrane module is suppress the formation of protein cake layer.

A Study on thinner's Physicochemical property and its effect on genital organ of rat (시너(thinner)의 물리화학적 특성과 랫트의 생식기에 미치는 영향 연구)

  • Kim, Hyeon-Yeong;Lee, Sung-Bae;Han, Jeong-Hee;Kim, Tae-Gyun;Lee, Jung-Suk;Kang, Min-Gu;Lee, Chae-Kwan
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.18 no.3
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    • pp.224-238
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    • 2008
  • The aim of this study is to confirm the physicochemical property and hazard of thinner (012), which is a diluent of enamel paint used for floor coating for waterproofing and oil painting for the outer wall. The literatures of physicochemical property and hazard of thinner were surveyed and its physicochemical property were evaluated. And then, the inhalation toxicity of thinner affecting the central nervous system and reproductive organs in rats were examined by subchronic (6 h./day. 5 days/ week for 13 weeks) inhalation test. 1) According to the 13-week subchronic inhalation test, there were no significant changes in clinical test and body weight. However, a significant evidence of toxicity was observed in the hematological test and organ weight such as heart, kidney, liver and brain (p<0.01) in the 200 ppm and 1,000 ppm exposure groups in a dose response manner. In the histopathology analysis, there were no significant evidence of toxicity. Therefore, thinner was not classified as an organ targeted toxic agent. In case of Harmfulness, it could be classified as a chronic toxic agent 3($500 ppm/4hr, rat). 2) The reproductive toxicity such as extension of the period of estrous cycle, reduction of serum estradiol concentration and increase of frequency of the abnormal sperm was observed in the 1,000 ppm exposed animals. 3) The result of the physicochemical property of the test material showed that the specific gravity was 0.793, boiling point $155.8^{\circ}C$, steam pressure 2.1 kPa, ignition point $34.5^{\circ}C$, and spontaneous ignition point $280^{\circ}C$. The endothermic and exothermic values were 371.4 J/g and 159.1 J/g. respectively. The explosion limit was 214 mg/l. These data showed that thinner could be classified as an explosion agent level 1.2 and ignitive liquid agent 3 ($23-60^{\circ}C$) according to the notification No. 2008-1 of the Labor Ministry, "Classifying Standard of Chemical Materials."