• Title/Summary/Keyword: Physical com

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Effects of Changes in Illumination Level and Slope on Fall-Related Biomechanical Risk Factors While Walking for Elderly Women (조도와 주로 변화가 노인 여성 보행 시 낙상 관련 운동역학적 위험요인에 미치는 영향)

  • Jeon, Hyun-Min;Park, Sang-Kyoon
    • Korean Journal of Applied Biomechanics
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    • v.25 no.4
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    • pp.413-421
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    • 2015
  • Objective : The purpose of this study was to investigate biomechanical changes of the lower limb including dynamic stability with changes in illumination (300Lx, 150Lx, and 5Lx) and slope (level and $15^{\circ}$ downhill) as risk factors for elderly falls. Method : Fifteen elderly females were selected for this study. Seven infrared cameras (Proreflex MCU 240: Qualisys, Sweden) and an instrumented treadmill (Bertec, USA) surrounded by illumination regulators and lights to change the levels of illumination were used to collect the data. A One-Way ANOVA with repeated measures using SPSS 12.0 was used to analyze statistical differences by the changes in illumination and slope. Statistical significance was set at ${\alpha}=.05$. Results : No differences in the joint movement of the lower limbs were found with changes in illumination (p>.05). The maximum plantar flexion movement of the ankle joints appeared to be greater at 5Lx compared to 300Lx during slope gait (p<.05). Additionally, maximum extension movement of the hip joints appeared to be greater at 5Lx and 150Lx compared to 300Lx during slope gait (p<.05). The maximum COM-COP angular velocity (direction to medial side of the body) of dynamic stability appeared to be smaller at 150Lx and 300Lx compared to 5Lx during level gait (p<.05). The minimum COM-COP angular velocity (direction to lateral side to the body) of dynamic stability appeared smaller at 150Lx compared to 5Lx during level gait (p<.05). Conclusion : In conclusion, elderly people use a stabilization strategy that reduces walk speed and dynamic stability as darkness increases. Therefore, the changes in illumination during gait induce the changes in gait mechanics which may increase the levels of biomechanical risk in elderly falls.

Effect of Multiple Copies of Cohesins on Cellulase and Hemicellulase Activities of Clostridium cellulovorans Mini-cellulosomes

  • Cha, Jae-Ho;Matsuoka, Satoshi;Chan, Helen;Yukawa, Hideaki;Inui, Masayuki;Doi, Roy H.
    • Journal of Microbiology and Biotechnology
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    • v.17 no.11
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    • pp.1782-1788
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    • 2007
  • Cellulosomes in Clostridium cellulovorans are assembled by the interaction between the repeated cohesin domains of a scaffolding protein (CbpA) and the dockerin domain of enzyme components. In this study, we determined the synergistic effects on cellulosic and hemicellulosic substrates by three different recombinant mini-cellulosomes containing either endoglucanase EngB or endoxylanase XynA bound to mini-CbpA with one cohesin domain (mini-CbpAl), two cohesins (mini-CbpA12), or four cohesins (mini-CbpAl234). The assembly of EngB or XynA with mini-CbpA increased the activity against carboxymethyl cellulose, acid-swollen cellulose, Avicel, xylan, and com fiber 1.1-1.8-fold compared with that for the corresponding enzyme alone. A most distinct improvement was shown with com fiber, a natural substrate containing xylan, arabinan, and cellulose. However, there was little difference in activity between the three different mini-cellulosomes when the cellulosomal enzyme concentration was held constant regardless of the copy number of cohesins in the cellulosome. A synergistic effect was observed when the enzyme concentration was increased to be proportional to the number of cohesins in the mini-cellulosome. The highest degree of synergy was observed with mini-CbpAl234 (1.8-fold) and then mini-CbpAl2 (1.3-fold), and the lowest synergy was observed with mini-CbpAl (1.2-fold) when Avicel was used as the substrate. As the copy number of cohesin was increased, there was more synergy. These results indicate that the clustering effect (physical enzyme proximity) of the enzyme within the mini-cellulosome is one of the important factors for efficient degradation of plant cell walls.

Properties of Particleboard Using Byproduct of Plywood Manufacture - Evaluation on the Elements of Surface Layer and Pre-treatment of Particles (합판 공장 부산물을 이용한 파티클보드의 물성에 관한 연구 - 표층 구성요소 및 파티클 전처리 여부에 따른 비교 -)

  • Hwang, Jung Taek;Pi, Duck Won;Kang, Seog Goo
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.1
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    • pp.33-41
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    • 2013
  • This study was performed to analyse cause of quality deterioration using byproduct of plywood and to determine physical and mechanical properties of particleboard used new bonding condition we found. The result of bending strength of Com-Ply board using EMDI is 57.7 $N/mm^2$ on linear direction and 25.1 $N/mm^2$ on vertical direction. EMDI has better water-resisting qualities than Urea formaldehyde adhesive according to result of thickness swelling and water absorption test. Pre-treatment soaked particle 72 hours in water caused increase of HCHO emission.

Application and Utilization of Social Network Resource: Concentrated on Changes of Spatial Meaning (소셜 네트워크 리소스(Social Network Resource)의 적용과 활용 -공간적 의미의 변화를 중심으로-)

  • Lee, Byung-Min
    • Journal of the Economic Geographical Society of Korea
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    • v.16 no.1
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    • pp.50-70
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    • 2013
  • The creation of new economic paradigm shift in creative economy age have influence on the characteristics of social networks and space, it leads to the formation of new relationship in space depending on social network service development. In this paper, it gives a name to 'social network resource' the power affecting these features and to find the meaning of spatial changes in the economic geography perspectives. 'Social network resource' shows the characteristics of openness, sharing, participation and cooperation, with features of encompassing all the features of local and global characteristics in space. This features are related the meaning of 'trans-locality' and can be found in the case of 'WikiSeoul.com (http:/www.wikiseoul.com)', Seoul's social knowledge sharing web platform. In particular, physical resources, human resources, information resources, and the characteristics of the relationship as a resource features was found and these features appear in space is projected to the space of social relations, it reflects the characteristics of qualitative space regarding social network resource.

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Effects of Foot Type and Ankle Joint Fatigue Levels on the Trajectories of COP and COM during a Single-Leg Stance (발의 유형과 발목 관절 피로 수준이 외발서기 시 압력중심점과 질량중심점 궤적에 미치는 영향)

  • Shin, Young-Hwa;Youm, Chang-Hong;Son, Min-Ji
    • Korean Journal of Applied Biomechanics
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    • v.23 no.4
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    • pp.335-345
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    • 2013
  • The purpose of this study was to investigate the effects of foot type and ankle joint fatigue levels on the trajectories of center of pressure and center of mass during a single-leg stance. The study subjects included 24 healthy women (normal foot group, n=10; pronated foot group, n=14). Ankle joint muscle fatigue was induced by using an isokinetic dynamometer, where the fatigue levels were measured on plantar flexion and dorsiflexion at angular velocities of $30^{\circ}/s$ at 50% and 30% of the peak torque of ankle plantar flexion. Following assessments in the anteroposterior direction according to the level of fatigue, the pronated foot group showed decreased single-leg stance ability at 50% and 30% of the fatigue level. Moreover, the normal foot group showed better single-leg stance ability than the pronated foot group at 30% of the fatigue level. Following assessments in the mediolateral direction, we noted that the single-leg stance ability did not differ significantly according to the levels of fatigue or foot type. In conclusion, ankle plantar flexion at 50% and 30% of the peak torque reduced the ability of the pronated foot group to achieve a single leg stance in the anteroposterior direction. Moreover, the normal foot group showed better single-leg stance ability than the pronated foot group.

A Kinetics Analysis of Forward 11/2 Somersault on the Platform Diving (플랫폼 다이빙 앞으로 서서 앞으로 11/2회전 동작의 운동역학적 분석)

  • Jeon, Kyoung-Kyu
    • Korean Journal of Applied Biomechanics
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    • v.23 no.3
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    • pp.209-218
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    • 2013
  • This study was to perform the kinetic analysis of forward $1\frac{1}{2}$ somersault on the platform diving. Six men's diving players of the Korea national reserve athletes participated in this study. The variables were analyzed response time, velocity, center of mass (COM), angle, center of pressure (COP) and ground reaction force (GRF) of motion. For measure and analysis of this study, used to synchronized to 4 camcorder and 1 force plate, used to the Kwon3D XP (Ver. 4.0, Visol, Korea) and Kwon GRF (Ver. 2.0, Visol, Korea) for analyzed of variables. The results were as follows; Time factor were observed in maximum knee flexion depending on the extent of use at phase 1 of take-off to execute the somersault. This enabled the subject to secure the highest possible body position in space at the moment of jumping to execute the somersault and prepare for the entry into the water with more ease. Regarding the displacement of COM, all subjects showed rightward movement in the lateral displacement during technical execution. Changes in forward and downward movements were observed in the horizontal and vertical displacements, respectively. In terms of angular shift, the shoulder joint angle tended to decrease on average, and the elbow joints showed gradually increasing angles. This finding can be explained by the shift of the coordinate points of body segments around the rotational axis in order to execute the half-bending movement that can be implemented by pulling the lower limb segments toward the trunk using the upper limb segments. The hip joint angles gradually decreased; this accelerated the rotational movement by narrowing the distance to the trunk. Movement-specific shifts in the COP occurred in the front of and vertical directions. Regarding the changes in GRF, which is influenced by the strong compressive load exerted by the supporting feet, efficient aerial movements were executed through a vertical jump, with no energy lost to the lateral GRF.

Effect of Addition of Enzyme-Resistent Starch on Texture Characterstics of Corn Bread (효소 저항성 전분의 첨가가 옥수수빵의 텍스쳐 특성에 미치는 영향)

  • 조아라;안승요
    • Korean journal of food and cookery science
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    • v.12 no.2
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    • pp.207-213
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    • 1996
  • Effects of replacement of corn starch with Amylomaize Vll starch and addition of enzyme-resistant starch on texture characteristics of com bread (CON) were investigated. Amylomaize-substituted corn bread (AMZ) was made by replacing corn starch with Amylomaize Vll starch. 15% (RSl5) and 30% (RS30) of butter, was replaced with enzyme-resistant starch (RS) from Amylomaife Vll starch, respectively. Textu,e describing terms were classified according to their physical properties. Result of sensory evaluation characteristics showed that the size of air cells increased as butter replacement level decreased and that hardness increased but springiness decreased as com starch was replaced with Amylomaize Vll starch. The results of Texture Profile Analysis with deformation of 30% and 50% showed that hardness inclosed but cohesiveness decreased as cooling time increased.

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Prevalence of obesity and overweight in Iranian children aged less than 5 years: a systematic review and meta-analysis

  • Mansori, Kamyar;Khateri, Sorour;Moradi, Yousef;Khazaei, Zaher;Mirzaei, Hossein;Hanis, Shiva Mansouri;Aliabadi, Mehran Asadi;Ranjbaran, Mehdi;Varse, Fatemeh;Parang, Serveh
    • Clinical and Experimental Pediatrics
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    • v.62 no.6
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    • pp.206-212
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    • 2019
  • Purpose: The present study aimed to determine the prevalence of childhood obesity and overweight in Iranian children under 5 years of age using a systematic review and meta-analysis. Methods: We searched MEDLINE (PubMed), Web of Science, Google Scholar, Scopus, CINHAL, and the Iranian databases, including Scientific Information Database (www.sid.ir), Iranian Research Institute for Information Science and Technology (Irandoc.ac.ir), Iranmedex (www.iranmedex.com), and Magiran (www.magiran.com), for all articles published between January 1989 and August 2017. Sources of heterogeneity were determined using subgroup analysis and meta-regression. Results: Six articles were ultimately included in the meta-analysis to estimate the pooled prevalence, based on which the prevalence of obesity and overweight were estimated to be 8% (95% confidence interval [CI], 6%-10%) and 9% (95% CI, 7%-11%), respectively. The results of the subgroup analysis showed that the prevalence of obesity in boys and girls was 9% (95% CI, 6%-13%) and 7% (95% CI, 4-10%), respectively, and the prevalence of overweight in boys and girls was 10% (95% CI, 5%-15%) and 9% (95% CI, 5%-13%), respectively. Conclusion: Despite high heterogeneity among the results of the articles included in the meta-analysis, the prevalence of obesity and overweight is higher in Iranian children under 5 years of age. Therefore, parents and the health system must pay more attention to the lifestyle, nutritional habits, and physical activity of these children.

Development of Higher functional Coating Agents for Pulp Mold (I) (펄프몰드용 새로운 고기능 코팅제 제조기술개발(제1보) - 합성 및 천연코팅제의 기능 구명 -)

  • 강진하;임현아
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.4
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    • pp.37-43
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    • 2002
  • In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of synthetic and natural coating agents on the market. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. AKD and PVA showed higher functions than the other synthetic coating agents, while functions of CMC, Com starch and Oxidized starch were higher than those of other natural coating agents. Based on concentrations, AKD 0.5%, PVA 10%, CMC 1.5%, corn starch 6% and oxidized starch 8% were appeared as the proper concentrations. W3 consider that AKD may be suitable for the storage of higher moisture vegetables and other food, and PVA may be suitable for higher oily fried food.

Case Study on the "Clicks and Mortar" Strategies of the Three Major Department Stores in Korea (백화점 3사의 온-오프라인 통합전략 사례 연구)

  • 최인혁;이영렬
    • Journal of Distribution Research
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    • v.9 no.1
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    • pp.1-24
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    • 2004
  • As the dot-com companies realize the importance of the traditional business operations such as product distribution and sourcing, the task of balancing business strategy and operations between electronic commerce and"bricks St mortar"channels is an ongoing challenge. However, there are no generic recipes for formulating business strategy that optimally bridges the physical and virtual operations. In order to provide some guidelines, this study examines the big 3 retailers in Korea, and their"clicks & mortar"strategy, assessing how the activities of each channel are integrated to achieve the synergy effect. This study analyzes the differences in the pattern of integration among the three retailers and traces the causes of those differences. It also figures out the relationship between the degree of integration and performance variables such as growth and cost. Finally. it defines the essential constraints on the process of integration along with managerial implications.

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