• 펄프종이기술
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• 제31권2호
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• pp.70-76
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• 1999

This study was to measure the potential of nonwoody fibrous material, kenaf. Whole stalk of kenaf, Hibiscus cannabinus was separated by two parts of bast and core portion, and cooked separately by alkaline method. Morphological characteristic was evaluated using confocal laser scanning microscope (CLSM) and fiber quality analyzer(FQA). The strength properties of handsheets, made by different mixing ration between kenaf base and core fibers, were measured. Cross-sectional area of bast fibers was smaller than that of core fibers, but the bast fibers had a thick cell wall and narrow lumen area. Bast fibers were longer in length than core fibers. Core fibers had thin cell walls, broad lumen areas, and short lengths, and they had collapsed shape even in water. These characteristics of core fibers affected strength properties of handsheet positively. When the amount of core fibers increased, the strength properties of handsheet were increased. When the amount of bast fibers increased, the handsheet had rougher surface and higher air permeability.

• 한국재료학회지
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• 제26권1호
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• pp.17-21
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• 2016

Pt@Cu/C core-shell catalysts were successfully prepared by impregnation of a carbon support with copper precursor, followed by transmetallation between platinum and copper. The Pt@Cu/C core-shell catalysts retained a core of copper with a platinum surface. The prepared catalysts were used for hydrogen production through catalytic dehydrogenation of decalin for eventual application to an onboard hydrogen supply system. Pt@Cu/C core-shell catalysts were more efficient at producing hydrogen via decalin dehydrogenation than Pt/C catalysts containing the same amount of platinum. Supported core-shell catalysts utilized platinum highly efficiently, and accordingly, are lower-cost than existing platinum catalysts. The combination of impregnation and transmetallation is a promising approach for preparation of Pt@Cu/C core-shell catalysts.

• 대한물리치료과학회지
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• 제24권2호
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• pp.17-26
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• 2017

Purpose: The importance of core exercise on muscle activation of the lower extremity has been studied. This study investigated the effects of core exercise using pressure biofeedback unit on muscle strength of lower extremity. Method: Fourteen healthy young adults (7 males and 7 females) were recruited. They were randomly separated two groups and performed core exercise using pressure biofeedback unit of one set for three minutes, 10sets per day for three weeks. Result: The mean of muscle strength of lower extremity, maximum power of muscle and peak TQ/BW in core exercise group significantly increased after core exercise using bio feedback unit (p<.05). Conclusion: These findings suggest that core exercise using pressure biofeed-back unit may help improving of muscle strength of lower extremity in young adults.

• 국제초고층학회논문집
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• 제8권3호
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• pp.193-199
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• 2019

For better structural performance and constructability, a new composite core wall system using steel plate columns at the corners of the core section was developed. Using the proposed core wall, nonlinear section analysis and 3-dimensional structural analysis were performed for the prototype core wall section and super high-rise building, respectively. The analysis results showed that, when compared to traditional RC core wall case, the use of the corner steel plate columns provided better structural capacity, which allows less wall thickness and re-bars. Further, due to such effects, the construction cost and time can be reduced despite the use of steel plate columns.

• 대한임베디드공학회논문지
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• 제6권4호
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• pp.231-241
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• 2011

Recently, system virtualization has been applied to consumer electronics (CE) such as smart mobile phones. Although multi-core processors have become a viable solution for complex applications of consumer electronics, the issue of utilizing multi-core resources in the virtualization layer has not been researched sufficiently. In this paper, we present a new hypervisor design and implementation for multi-core CE devices. We concretely describe virtualization methods for a multi-core processor and multi-core-related subsystems. We also analyze bottlenecks of network performance in a virtualization environment that supports multimedia applications and propose an efficient virtual interrupt distributor. Our new multi-core hypervisor improves network performance by 5.5 times as compared to a hypervisor without the virtual interrupt distributor.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3528-3542
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• 2021

A detailed geometrical model of a Krško reactor core was developed using a Monte Carlo neutron transport code MCNP. The main goal of developing an MCNP core model is for it to be used in future research focused on ex-core calculations. A script called McCord was developed to generate MCNP input for an arbitrary fuel cycle configuration from the diffusion based core design package CORD-2, taking advantage of already available material and temperature data obtained in the nuclear core design process. The core model was used to calculate 3D power density profile inside the core. The applicability of the calculated power density distributions was tested by comparison to the CORD-2 calculations, which is regularly used for the nuclear core design calculation verification of the Krško core. For the hot zero power and hot full power states differences between MCNP and CORD-2 in the radial power density profile were <3%. When studying axial power density profiles the differences in axial offset were less than 2.3% for hot full power condition. To further confirm the applicability of the developed model, the measurements with in-core neutron detectors were compared to the calculations, where differences of 5% were observed.

• Physical Therapy Rehabilitation Science
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• 제12권1호
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• pp.56-61
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• 2023

Objective: Core training is a key exercise for conditioning and fitness programs, injury prevention, and more. This study aimed to find out the effect of adding dynamic core training, which is frequently prescribed in clinical practice, on dynamic balance and muscle activity compared to conventional static core training. Design: An experimental study Methods: This study is an experimental pilot study of prospective parallel design. Six healthy young adults were allocated to static core training group (SCG; crunch and plank) and blended group (BG; crunch, plank, and dead bug exercise) for two weeks to perform core training. Dynamic balance and muscle activity (erector spinae, rectus abdominis) were measured for all participants before and after core training. Results: All six healthy young adults enrolled completed the study. No significant difference was found before and after 6 sessions of core training in each group (P>0.05). Likewise, no significant difference was found in the results of the difference comparison between groups (P>0.05). Conclusions: In conclusion, in this experimental study, no difference was found when dynamic core training was added. Although the results before and after core training did not show improvement in dynamic balance and muscle activity, a randomized controlled trial is needed considering the results of previous studies and the limitations of this experimental study.

• 디지털산업정보학회논문지
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• 제13권4호
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• pp.71-79
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• 2017

Recently, Fire watching and dangerous substances monitoring system has been being developed to enhance various fire related security. It is generally assumed that fire flame extraction plays a very important role on this monitoring system. In this study, we propose the fire flame extraction method of Non-Residential Facilities based on core object extraction in image. A core object is defined as a comparatively large object at center of the image. First of all, an input image and its decreased resolution image are segmented. Segmented regions are classified as the outer or the inner region. The outer region is adjacent to boundaries of the image and the rest is not. Then core object regions and core background regions are selected from the inner region and the outer region, respectively. Core object regions are the representative regions for the object and are selected by using the information about the region size and location. Each inner region is classified into foreground or background region by comparing its values of a color histogram intersection of the inner region against the core object region and the core background region. Finally, the extracted core object region is determined as fire flame object in the image. Through experiments, we find that to provide a basic measures can respond effectively and quickly to fire in non-residential facilities.

• 한국콘텐츠학회논문지
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• 제8권9호
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• pp.27-33
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• 2008

Linux에서 사용되는 Shared Memory는 동일한 메모리 영역에 여러 개의 프로세스가 접근할 수 있도록 해 주는 기술이다. 본 논문은 Linux 운영체제에서 지원해 주는 System V의 IPC 중 하나인 Shared Memory를 Dual Core 시스템 상에서 동작하도록 구현한다. 본 논문에서는 커널 단계에서 처리되는 SVR(System V Release) 형식의 Shared Memory를 다룬다. 기존의 공유메모리 방식은 단일 처리기를 이용한 방식이다. 본 논문에서는 dual core를 이용하여 공유메모리 처리를 할 수 있는 시스템을 제안한다. 본 논문에서 제안하는 Dual Core 시스템에서 공유 메모리 기능 구현은 기존의 단일 처리기 시스템에서보다 성능을 향상시킬 수 있도록 한다. 공유 메모리를 이용한 프로세스의 동작이 별개의 CPU에서 동작되도록 함으로써 성능 향상을 꾀한다.

• 한국응용과학기술학회지
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• 제37권3호
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• pp.496-508
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• 2020

This study reviews studies on the core stabilization of respiratory muscle training for the elderly health. Previous research data and presenting basic literature data suggest that respiratory activation is an important mechanism for core strengthening via exercise interventions for the elderly. The review found that first, the mechanism of improving the respiratory muscles weakened by aging to address the loss of core function due to old age sarcopenia among the elderly results entails promoting the autonomic nervous system by focusing on the respiratory muscle activation pattern, the core muscle sensation mobilized for body centering. Second, nerve roots, intraperitoneal pressure, and deep muscles in the trunk of the body can be promoted while controlling respiratory stimulation with cognitive feedback. Effortful inspiration increases the activation of respiratory assistive muscles and effortless exhalation can improve the core muscle mobilization by involving abdominal muscles. Third, through respiratory muscle training, the elderly can increase their awareness of spinal centering and improve the ability to control the deep core muscles that must be mobilized for core stabilization. In conclusion, respiratory muscle training to increase the utilization of the trunk muscles seems to be a useful core stabilization exercise for the elderly with chronic tension and joint degeneration.