• Title/Summary/Keyword: Impact pressure

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Impact of Concurrent Inspiratory Muscle Training and Tape on Inspiratory Muscle Strength, Endurance and Pulmonary Function (들숨근 훈련과 테이핑 동시적용이 호흡의 근력, 지구력, 폐기능 향상에 미치는 영향)

  • Lee, Minsoo;Kim, Myungchul;Ahn, Chungjoa
    • Journal of The Korean Society of Integrative Medicine
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    • v.2 no.3
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    • pp.65-73
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    • 2014
  • Purpose: The purpose of this study was to identify the effect of a kinesio tape on inspiratory muscle training(IMT) to improve muscle strength, endurance and pulmonary function. Methods: Healthy 20 males were divided into IMT group (control group) and IMT with tape group (experimental group). The same IMT program was applied to both groups using the Respifit S for four weeks, three times a week, a total 12 times. To exprimental group, kinesio tape was applied on the inspiratory agonist diaphragm and the accessory inspiratory muscle scalene, sternocleidomastoid, pectoralis minor. The inspiratory pulmonary muscle strength was measured by the maximal inspiratory pressure (PI max) and minute volume (MV) using the Respifit S and the pulmonary function were measured peak expiratory flow (PEF), forced vital capacity (FVC), forced expiratory volume in 1sec (FEV1), FEV1/FVC using the Spirometer and compared before and after. Results: Results showed that the PI max in the two groups increased significantly and experimental group increased more effectively than that of control group. However, only MV showed a significant increase in experimental group but was not significantly different between the two groups. PEF and FEV1/FVC are significantly increased in both groups, but they did not make much difference between two groups, and the FVC for the two groups did not increase significantly. FEV1 increased significantly only with control group, but did not make a difference with experimental group. Conclusion: These result show that the PI max value for experimental group increased significantly than that of control group. Therefore kinesio tape maximizes inspiratory muscle exercise effect on muscle strength improvement. However, because of the short experimental period and difficulty in subject control, increase values of the others did not show a significant difference. In other words, kinesio tape did not show maximizing the inspiratory muscle exercise effect to improve endurance and pulmonary function.

Initiation and Growth Behavior of Small Fatigue Cracks in the Degraded 2 1/4 Cr-1 Mo Steel (2 1/4 Cr-1 Mo강 劣化材의 微小 疲勞龜裂의 발생 및 진전거동)

  • 곽상국;장재영;권재도;최선호;장순식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.1
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    • pp.53-62
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    • 1992
  • Material can be degraded by using it for a long service under the high temperature and pressure circumstances, Therefore, material degradation can affect the strength of mechanical structures. At present, the life prediction of the degraded structures is considered as an important technical problem. In this paper, the degraded 21/4Cr-lMo steel is the material used for about 10 years around 400.deg. C in an oil refinery plant. The recovered one was prepared out of the above degraded steel by heat treatment for one hour at 650.deg. C. The degradation effect was investigated through the tension test, Hardness test and Charpy impact test. On the smooth surface material, the fatigue crack initiation, growth and coalescence stages of the distributed small cracks were investigated with photographs, and the crack length and density were measured. The measuring results were analyzed by quantative and statistical methods.

An Overview of Biopulping Research: Discovery and Engineering

  • Scott, Gary M.;Akhtar, Masood;Lentz, Michael J.;Horn, Eric;Swaney, Ross E.;Kirk, T.Kent
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.30 no.4
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    • pp.18-27
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    • 1998
  • Biopulping is defined as the treatment of wood chips with lignin-degrading fungi prior to pulping. Fungal pretreatment prior to mechanical pulping reduces electrical energy requirements during refining or increases mill throughput, improves paper strength, reduces the pitch content, and reduces the environmental impact of pulping. Our recent work involved scaling up the biopulping process towards the industrial level, investigating both the engineering and economic feasibility. We envision the process to be done in either a chip-pile or silo-based system for which several factors need to be considered: the degree of decontamination, a hospitable environment for the fungus, and the overall process economics. Currently, treatment of the chips with low-pressure steam is sufficient for decontamination and a simple, forced ventilation system maintains the proper temperature, humidity, and moisture conditions, thus promoting uniform growth of the fungus. The pilot-scale trial resulted in the successful treatment of 4 tons of wood chips (dry weight basis) with results comparable to those on a laboratory. Larger, 40-ton trials were also successful, with energy savings and paper properties comparable with the laboratory scale. The overall economics of the process also look very favorable and can result in significant annual savings to the mill. Although the current research has focused on biopulping for mechanical pulping, it is also beneficial for sulfite chemical pulping and some applications to recycled fiber have been investigated.

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Experimental Investigations into the Precision Cutting of High-pressured Jet for Thin Multi-layered Material (다층박판재료의 초고압 젯 정밀가공에 대한 실험적 연구)

  • Park, Kang-Su;Bahk, Yeon-Kyeung;Lee, Jung-Han;Lee, Chae-Moon;Go, Jeung-Sang;Shin, Bo-Sung
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.7
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    • pp.44-50
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    • 2009
  • High-pressured jetting is now widely used in the advanced cutting processes of polymers, metals, glass, ceramics and composite materials because of some advantages such as heatless and non-contacting cutting. Similarly to the focused laser beam machining, it is well known as a type of high-density energy processes. High-pressured jetting is going to be developed not only to minimize the cutting line width but also to achieve the short cutting time as soon as possible. However, the interaction behavior between a work piece and high-velocity abrasive particles during the high-pressured jet cutting makes the impact mechanism even more complicated. Conventional high-pressured jetting is still difficult to apply to precision cutting of micro-scaled thin work piece such as thin metal sheets, thin ceramic substrates, thin glass plates and TMM (Thin multi-layered materials). In this paper, we proposed the advanced high-pressured jetting technology by introducing a new abrasives supplying method and investigated the optimal process conditions of the cutting pressure, the cutting velocity and SOD (Standoff distance).

Experimental Study on Air Decomposition By-Product Under Creepage Discharge Fault and Their Impact on Insulating Materials

  • Javed, Hassan;LI, Kang;Zhang, Guoqiang;Plesca, Adrian Traian
    • Journal of Electrical Engineering and Technology
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    • v.13 no.6
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    • pp.2392-2401
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    • 2018
  • Creepage discharge faults in air on solid insulating material play a vital role in degradation and ageing of material which ultimately leads to breakdown of power equipment. And electric discharge decompose air in to its by-products such as Ozone and $NO_x$ gases. By analyzing air decomposition gases is a potential method for fault diagnostic in air. In this paper, experimental research has been conducted to study the effect of creepage discharge on rate of generation of air decomposition by-products using different insulating materials such as RTV, epoxy and fiberglass laminated sheet. Moreover XRF analysis has been done to analyze creepage discharge effect on these insulating materials. All experiments have been done in an open air test cell under constant temperature and pressure conditions. While analysis has been made for low and high humidity conditions. The results show that the overall concentration of air decomposition by-products under creepage discharge in low humidity is 4% higher than concentration measured in high humidity. Based on this study a mathematical relationship is also proposed for the rate of generation of air decomposition by-products under creepage discharge fault. This study leads to indirect way for diagnostic of creepage discharge propagation in air.

The Effect of ABO Blood Groups, Hemoglobinopathy, and Heme Oxygenase-1 Polymorphisms on Malaria Susceptibility and Severity

  • Kuesap, Jiraporn;Na-Bangchang, Kesara
    • Parasites, Hosts and Diseases
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    • v.56 no.2
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    • pp.167-173
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    • 2018
  • Malaria is one of the most important public health problems in tropical areas on the globe. Several factors are associated with susceptibility to malaria and disease severity, including innate immunity such as blood group, hemoglobinopathy, and heme oxygenase-1 (HO-1) polymorphisms. This study was carried out to investigate association among ABO blood group, thalassemia types and HO-1 polymorphisms in malaria. The malarial blood samples were collected from patients along the Thai-Myanmar border. Determination of ABO blood group, thalassemia variants, and HO-1 polymorphisms were performed using agglutination test, low pressure liquid chromatography and polymerase chain reaction, respectively. Plasmodium vivax was the major infected malaria species in the study samples. Distribution of ABO blood type in the malaria-infected samples was similar to that in healthy subjects, of which blood type O being most prevalent. Association between blood group A and decreased risk of severe malaria was significant. Six thalassemia types (30%) were detected, i.e., hemoglobin E (HbE), ${\beta}$-thalassemia, ${\alpha}$-thalassemia 1, ${\alpha}$-thalassemia 2, HbE with ${\alpha}$-thalassemia 2, and ${\beta}$-thalassemia with ${\alpha}$-thalassemia 2. Malaria infected samples without thalassemia showed significantly higher risk to severe malaria. The prevalence of HO-1 polymorphisms, S/S, S/L and L/L were 25, 62, and 13%, respectively. Further study with larger sample size is required to confirm the impact of these 3 host genetic factors in malaria patients.

Study of Determination in Measurement System for Safely Managing Debris-Flow (안전한 토석류 관리를 위한 계측기 선정에 관한 연구)

  • Min, Dae-Hong;Yoon, Hyung-Koo
    • Journal of the Korean Society of Safety
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    • v.32 no.3
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    • pp.41-47
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    • 2017
  • Recent studies have shown that there are various systems which can be used to monitor hazardous area in a debris flow location, but lack of methodological research on the exact location where each instrument should be installed has hindered the success of this systems. The objective of this study is to suggest the measurement system for monitoring debris-flow and propose the effective method to determine location of measurement system. Previously studied, from 1991 to 2015, were referred and the applied ratio of every instrument was investigated. The measurement information was divided into 8 categories including rainfall, debris-flow velocity, displacement, fluid pore pressure, ground vibration, image processing, impact force and peak flow depth. The result of this study revealed that the most applied instruments to be rain gauge and geophone for measuring average rainfall and ground vibration respectively. The Analytic Hierarchical Process (AHP) method was selected to determine installation location of instrument and the weighting factors were estimated through fine content, soil thickness, porosity, shear strength, elastic modulus, hydraulic conductivity and saturation. The soil thickness shows highest weights and the fine content relatively demonstrates lowest weights. The score of each position can be calculated through the weighting factors and the lowest score position can be judged as the weak point. The weak point denotes the easily affecting area and thus, the point is suitable for installing the measurement system. This study suggests a better method for safely managing the debris-flow through a precise location for installing measurement system.

Related Factors of Depression according to Individual Attributes and Regional Environment: Using Multi-Level Analysis (다수준분석을 활용한 개인특성 및 지역환경에 따른 우울증 관련 영향요인 분석)

  • Moon, Seok-Jun;Lee, Ga Ram;Nam, Eun-Woo
    • Health Policy and Management
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    • v.30 no.3
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    • pp.355-365
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    • 2020
  • Background: This study is aimed to verify individual and regional-level factors affecting the depression of Koreans and to develop social programs for improving the depressive status. Methods: This study used individual-level variables from the Korean Community Health Survey (2018) and used the e-regional index of the Korean Statistical Information Service as the regional-level variable. A multi-level logistic regression was executed to identify individual and regional-level variables that were expected to affect the extent of depressive symptoms and to draw the receiver operating characteristic curve to compare the volume of impact between variables from both levels. Results: The results of the multi-level logistic regression analysis in regards to individual-level factors showed that older age, female gender, a lower income level, a lower education level, not having a spouse, the practice of walking, the consumption of breakfast higher levels of stress, and having high blood pressure or diabetes were associated with a greater increase in depressive symptoms. In terms of regional factors, areas with fewer cultural facilities and fewer car registration had higher levels of depressive symptoms. The comparison of area under the curve showed that individual factors had a greater influence than regional factors. Conclusion: This study showed that while both, individual and regional-level factors affect depression, the influence of the latter was relatively weaker as compared to the first. In this sense, it is necessary to develop programs focused on the individual, such as social prescribing at the local or community-level, rather than the city and nation-level approach that are currently prevalent.

The Fundamental Study on the Development of Leisure Boat's Drop Test Management System based on ISO 12215-5 (ISO 12215-5에 기반 한 레저선박 낙하시험 평가시스템 개발을 위한 기초연구)

  • Kang, Nam-Seon;Park, Chung-Hwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.4
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    • pp.365-370
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    • 2012
  • International Organization for Standardization has recently published ISO 12215-5 which is the small craft-hull construction and scantling. According to ISO 12215-5 AnnexB, the scantling determination can be accomplished by drop test for craft with a length $L_H$ of 2.5m up to 6m and single-skin construction. The current method, however, of visual test has the issue where it is difficult to make an objective evaluation of ship body strength. In this study, in order to develop an evaluation system that can make a quantitative evaluation of the drop test of leisure boats, the domestic/foreign regulations on drop test of leisure boats are analyzed and the drop test evaluation system is designed, and the system applicability is reviewed through 5-meter level aluminum ship, and the issues incurred by the state of the ship and the posture while dropping were checked.

Failure characteristics of combined coal-rock with different interfacial angles

  • Zhao, Tong-Bin;Guo, Wei-Yao;Lu, Cai-Ping;Zhao, Guang-Ming
    • Geomechanics and Engineering
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    • v.11 no.3
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    • pp.345-359
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    • 2016
  • In order to investigate the influence of the interfacial angel on failure characteristics and mechanism of combined coal-rock mass, 35 uniaxial/biaxial compressive simulation tests with 5 different interfacial angels of combined coal-rock samples were conducted by PFC2D software. The following conclusions are drawn: (1) The compressive strength and cohesion decrease with the increase of interfacial angle, which is defined as the angle between structure plane and the exterior normal of maximum principal plane, while the changes of elastic modulus and internal friction angle are not obvious; (2) The impact energy index $K_E$ decreases with the increase of interfacial angle, and the slip failure of the interface can be predicted based on whether the number of acoustic emission (AE) hits has multiple peaks or not; (3) There are four typical failure patterns for combined coal-rock samples including I (V-shaped shear failure of coal), II (single-fracture shear failure of coal), III (shear failure of rock and coal), and IV (slip rupture of interface); and (4) A positive correlation between interfacial angle and interface effect is shown obviously, and the interfacial angle can be divided into weak-influencing scope ($0-15^{\circ}$), moderate-influencing scope ($15-45^{\circ}$), and strong-influencing scope (> $45^{\circ}$), respectively. However, the confining pressure has a certain constraint effect on the interface effect.