• Journal of Korean Association for Spatial Structures
• /
• v.13 no.3
• /
• pp.45-55
• /
• 2013

The core aim of this paper is to empirically scrutinize a strength characteristic and ductility of the beam-column frame of reinforced with steel subjected to the cyclic lateral load. First and foremost, I the author embarks upon making four prototypes vis-$\grave{a}$-vis this research. Through this endeavour, the author has analysed cyclic behavior, fracture shape, ductility and energy dissipation of the normal beam-column frame and a beam-column frame of reinforced with steel. In addition, the survey has revealed the exact stress transfer path and the destructive mechanism in order to how much a beam-column frame of reinforced with steel has resistance to earthquake regarding all types of building, as well as school construction. To get the correct data, the author has compared the normal beam-column frame and three types of the beam-column frame of reinforced with steel following these works, the characteristic of cyclic behavior, destructive mechanism, ductility, and Energy dissipation of normal beam-column frame and a beam-column frame of reinforced with steel have been examined clearly.

• International Journal of Fluid Machinery and Systems
• /
• v.4 no.1
• /
• pp.57-66
• /
• 2011

Radial-vaned air separators show a strong stall suppression effect in an axial flow fans. From a survey of existing literature on the effects and the author's data, a possible mechanism for the significant effects has been proposed here. The stall suppression is suggested to have been achieved by a combination of the following several effects; (1) suction of blade and casing boundary layers and elimination of embryos of stall, (2) separation and straightening of reversed swirling flow from the main flow, (3) induction of the fan main flow toward the casing wall and enhancement of the outward inclination of meridional streamlines across the rotor blade row, thus keeping the Euler head increase in the decrease in fan flow rate, and (4) reinforcement of axi-symmetric structure of the main flow. These phenomena have been induced and enhanced by a stable vortex-ring encasing the blade tips and the air separator. These integrated effects appear to have caused the great stall suppression effect that would have been impossible by other types of stall prevention devices. Thus the author would like to name the device "tip-vortex-ring assisted stall suppression device".

• Journal of Korean Academy of Nursing
• /
• v.26 no.3
• /
• pp.678-687
• /
• 1996

Smoking is considered to be one of the important risk factors associated with various health problems. Thirty seven million people in America quit smoking in the past decade, with 90% quitting on their own(Americal Heart Association, 1986). According to McAlister(1975), 70% of smokers reported that they adopted a self-help smoking cessation approach rather than a formal treatment program. In our country, although, auccessful exsmokers have used, are not available, concerns about smoking cessation have increased, recently, due to changes in social and political attitudes to health promotion. This study was conducted to help smokers who had made a decision to adopt a self-helf smoking cessation approach instead of depending on a formal treatment program. It provided a structurd way for sucessful smoking cessation by identifying change mechanism factors which have been commonly used by smokers. The subjects selected for this study were 155 university students between 20 and 29. Years of age the results from the analysis of the collected data showed that seven factors in the self-help change processes significant, and they are named, Stimulus Control, Self-Determination, Information Management, Reinforcement Management, Helpful Relationships, Dramatic Relief, and Cognitive Restructuring. All of the factors except Self-Determination represent the same change mechanisms which are proposed by Prochaska et at.(1988). Self-Determination uniformly includes items belonging to various change processes. Therefore, it might be an transitional factor including strategies related to both cognitive and behavioral dimensions. In spite of this, noted that one item which gives meaning of Self-Determination shows the highest factor loading, it is named Self-Determination.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.5 no.4
• /
• pp.19-30
• /
• 2002

The stability of slope using root-pile like to the reinforcements is affected by the interaction behavior mechanism of soil-reinforcements. Through the studying on the interaction in joint of its, therefore, the control roles can be find out in installed slope. In study, the stress level ratio based on the insert angle of installed reinforcements in soil used to numerical analysis, which was results from the duty direct shear test in Lab. The maximum shear strain variation on the reinforcements was observed at insert angle, which was approximately similar to the calculated angle based on the equation proposed by the Jewell. The elasto-plastic joint model on the contact area of soil-reinforcements was presumed, the reinforced soil assumed non-linear elastic model and the reinforcements supposed elastic model, respectively. The finite element analysis of assumed models was performed. The shear strain variation of non-reinforced state obtained by the FEM analysis including elasto-plastic joint elements were shown the rationality of general limit equilibrium analysis for the slope failure mode on driving zone and resistance zone, which based on the stress level step according to failure ratio. Through the variation of shear strain for the variation of inserting angle of reinforcements, the different mechanism on the bending and the shear resistance of reinforcements was shown fair possibility.

• Korean Journal of Metals and Materials
• /
• v.48 no.11
• /
• pp.1003-1008
• /
• 2010

In this study, the effect of the reinforcement on the wear behaviour and mechanical properties of hypereutectic Al-Si alloys was investigated. The Gas atomized hypereutectic Al-20Si alloy powders were mixed with 1, 3, and 5 wt.% AlN and TiC ceramic particles and consolidated by hotpress. The Al-20Si powder has both finely dispersed primary Si phases and eutectic structures. The Al-20Si-AlN, TiC composites showed that the reinforcements were distributed along the boundary of the Al-20Si alloy. The UTS increased with increasing the AlN, TiC contents. At a lower load, with an increasing weight fraction of reinforcements, the wear rate decreased in both composites and the wear mechanism was adhesive wear. At a higher load, the shape of the debris changes the mechanism of the AlN composites to abrasive-adhesion wear and this resulted in an increase of the wear rate.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.9
• /
• pp.4572-4586
• /
• 2019

Mobile Edge Computing (MEC) and Information-Centric Networking (ICN) are essential network architectures for the future Internet. The advantages of MEC and ICN such as computation and storage capabilities at the edge of the network, in-network caching and named-data communication paradigm can greatly improve the quality of video streaming applications. However, the packet loss in wireless network environments still affects the video streaming performance and the existing loss recovery approaches in ICN does not exploit the capabilities of MEC. This paper proposes a Deep Learning based Loss Recovery Mechanism (DL-LRM) for video streaming over MEC based ICN. Different with existing approaches, the Forward Error Correction (FEC) packets are generated at the edge of the network, which dramatically reduces the workload of core network and backhaul. By monitoring network states, our proposed DL-LRM controls the FEC request rate by deep reinforcement learning algorithm. Considering the characteristics of video streaming and MEC, in this paper we develop content caching detection and fast retransmission algorithm to effectively utilize resources of MEC. Experimental results demonstrate that the DL-LRM is able to adaptively adjust and control the FEC request rate and achieve better video quality than the existing approaches.

• Annual Conference on Human and Language Technology
• /
• 2020.10a
• /
• pp.167-171
• /
• 2020

문서 요약은 길이가 긴 원본 문서에서 의미를 유지한 채 짧은 문서나 문장을 얻어내는 작업을 의미한다. 딥러닝을 이용한 자연어처리 기술들이 연구됨에 따라 end-to-end 방식의 자연어 생성 모델인 sequence-to-sequence 모델을 문서 요약 생성에 적용하는 방법들이 연구되었다. 본 논문에서는 여러 자연어처리 분야에서 높은 성능을 보이고 있는 BERT 모델을 이용한 자연어 생성 모델에 복사 메커니즘과 강화 학습을 추가한 문서 요약 모델을 제안한다. 복사 메커니즘은 입력 문장의 단어들을 출력 문장에 복사하는 기술로 학습데이터에서 학습되기 힘든 고유 명사 등의 단어들에 대한 성능을 높이는 방법이다. 강화 학습은 정답 단어의 확률을 높이기 위해 학습하는 지도 학습 방법과는 달리 연속적인 단어 생성으로 얻어진 전체 문장의 보상 점수를 높이는 방향으로 학습하여 생성되는 단어 자체보다는 최종 생성된 문장이 더 중요한 자연어 생성 문제에 효과적일 수 있다. 실험결과 기존의 BERT 생성 모델 보다 복사 메커니즘과 강화 학습을 적용한 모델의 Rouge score가 더 높음을 확인 하였다.

• Steel and Composite Structures
• /
• v.48 no.2
• /
• pp.131-143
• /
• 2023

The CFRP bar was used to achieve more ductile and durable headed-stud shear connectors in composite components. Three series of push-out tests were firstly conducted, including specimens reinforced with pure steel fibers, steel and CFRP bars. The distributed stress was measured by the commercial PPP-BOTDA (Pre-Pump-Pulse Brillouin optical time domain analysis) optical fiber sensor with high spatial resolution. A series of numerical analyses using non-linear FE models were also made to study the shear force transfer mechanism and crack response based on the test results. Test results show that the CFRP bar increases the shear strength and stiffness of the large diameter headed-stud shear connection, and it has equivalent reinforcing effects on the stud shear capacity as the commonly used steel bar. The embedded CFRP bar can also largely improve the shear force transfer mechanism and decrease the tensile stress in the transverse direction. The parametric study shows that low content steel fibers could delay the crack initiation of slab around the large diameter stud, and the CFRP bar with normal elastic modulus and the standard reinforcement ratio has good resistance to splitting crack growth in headed stud shear connectors.

• Geomechanics and Engineering
• /
• v.31 no.1
• /
• pp.71-86
• /
• 2022

In Taiwan, an efficient approach for enhancing the stability of colluvium slopes is the drilled shaft method. For slopes with drilled shafts, the soil arching effect is one of the primary factors influencing slope stability and intertwines to the failure mechanism of the pile-soil system. In this study, the contribution of soil arching effect to slope stability is evaluated using the FEM software (Plaxis 3D) with the built-in strength reduction technique. The result indicates the depth of the failure surface is influenced by the S/D ratio (the distance to the diameter of piles), which can reflect the contribution of the soil arching effect to soil stability. When α (rock inclination angles)=β (slope angles) is considered and the S/D ratio=4, the failure surface of the slope is not significantly influenced by the piles. Overall, the soil arching effect is more significant on α=β, especially for the steep slopes. Additionally, the soil arching effect has been included in the proposed stability charts. The proposed charts were validated through two case studies, including that of the well-known Woo-Wan-Chai field in Taiwan. The differences in safety factor (FoS) values between the referenced literature and this study was approximately 4.9%.

• Journal of the Korean Geosynthetics Society
• /
• v.18 no.1
• /
• pp.25-37
• /
• 2019

This study confirms reinforcing effect of geosynthetics in the use of soil at higher water contents as a compaction material on compaction tests, field compaction tests, and numerical analysis. To verify a confined effect, a large mold(area ratio of rammer / mold = 0.19) larger than D compaction mold(area ratio of rammer / mold = 0.33) was performed for compaction. It showed that in the D compaction test, dry density were 0.5~0.6% increases and in the compaction test using the large mold, it were 2.4~3.7% increases at high water contents. It shows that when the area of compacted area is large enough, a confined effect could be arising from the reinforcement of geosynthetics even at high water contents. As a result of analyzing of compaction effects according to 'depth(z/B) from compacted surface' in the field, when not reinforced, the compaction state deteriorated due to the over-compaction and the compaction did not work well. However, when reinforcement of geosynthetics, restraint effect by geosynthetics occurs, it is confirmed that the compaction energy is effectively transferred to the compaction layer and the dry density is increased. Also, through the conceptual model of the behavior of geosynthetic and soil layer, the mechanism in the ground due to reinforcement of geosynthetics is presented and it is verified through finite element analysis.