• Title/Summary/Keyword: Self-interference

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Practical resolution of angle dependency of multigroup resonance cross sections using parametrized spectral superhomogenization factors

  • Park, Hansol;Joo, Han Gyu
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1287-1300
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    • 2017
  • Based on the observation that ignoring the angle dependency of multigroup resonance cross sections within a fuel pellet would result in nontrivial underestimation of the spatial self-shielding of flux, a parametrized spectral superhomogenization (SPH) factor library (PSSL) method is developed as a practical means of resolving the problem. Region-wise spectral SPH factors are calculated by the normal and transport corrected SPH iterations after ultrafine group slowing down calculations over various light water reactor pin-cell configurations. The parametrization is done with fuel temperature, U-238 number density, fuel radius, moderator source represented by ${\Sigma}_{mod}V_{mod}$, and the number density ratio of resonance nuclides to that of U-238 in a form of resonance interference correction factors. The parametrization is successful in that the root mean square errors of the interpolated SPH factors over the fuel regions of various pin-cells are within 0.1%. The improvement in reactivity error of the PSSL method is shown to be superior to that by the original SPH method in that the reactivity bias of -200 pcm to -300 pcm vanishes almost completely. It is demonstrated that the environment effect takes only about 4% in the reactivity improvement so that the pin-cell based PSSL method is effective in the assembly problems.

The Effect of Driving Simulator Program on Elderly Drivers

  • Kim, Deokju
    • International Journal of Advanced Culture Technology
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    • v.9 no.2
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    • pp.18-31
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    • 2021
  • The purpose of the present study was to present evidence for driving interventions for the elderly by conducting programs that can improve visual perception and cognitive function in a driving simulator for elderly drivers and analyse their effects. Three elderly subjects who were 65 years or older, did not have physical and cognitive impairments, and were able to drive themselves participated in the present study. A total of 12 intervention sessions, of which subjects participated in 10 sessions of nine different visual perception and cognitive function programs available in a driving simulator, were conducted and pre- and post-program assessments were conducted (two assessments in total). The assessments included the evaluation of visual perception, frontal lobe function, concentration, safe driving behaviour, and self-efficacy. The results showed positive effects of the driving simulator program on the visual perception, frontal lobe function, concentration, safe driving behaviour, and self-efficacy of all subjects. Changes in the simulator results showed remarkable improvement in the response evaluation, judgment evaluation, and predictive power evaluation, but showed difficulties in interference tasks and depth perception in common. The results showed positive effects of driving simulator training on the driving ability of the elderly, and consistent provision of such training is expected to improve the quality of life of the elderly by securing the safety of driving and actively supporting social participation.

Reception Performance Improvement of the Long-Haul WDM System with the Channel Interference Due to FWM Effect through the Power Symmetric Mid-Span Spectral Inversion (FWM에 의한 채널 간섭이 존재하는 장거리 WDM 시스템에서의 전력 대칭 MSSI 보상법을 통한 수신 성능 개선)

  • 이성렬;장원호;이윤현
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.7
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    • pp.716-725
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    • 2002
  • In this paper, we showed the applicability of power symmetric MSSI(Mid-Span Spectral Inversion) to the long-haul WDM system with the channel interference due to FWM(Four Wave Mixing). And we showed the degree of performance improvement. We used 1 dB EOP(Eye-Opening Penalty) criterion so as to evaluate the degree of compensation dependent on the variation of chirp parameter of optical pulse for the various input power in high speed tansmission system. And we evaluated the maximum input power of channel be able to be the signal to crosstalk noise (SNR) above 20 dB in the transmission link with the channel interference due to FWM. Consequently the proposed MSSI compensation method is capable to transmitting the total 68 WDM channels simultaneously with a 0.4 nm channel spacing and 5.3 dBm maximum input power in a 10 Gbps transmission link. Therefore the proposed power symmetric MSSI compensation method may be very useful for the implementation of long-haul wideband WDM transmission systems with relatively high power and improved performance.

The Effects of Self-Control, Parental Behaviors, and Marital Conflict on Boys' Aggression in Korean Upper Elementary School Students (초등학생 고학년 남아의 자기통제력, 부모의 양육행동, 부모간 갈등이 공격성에 미치는 영향)

  • Jun, Joo-Ram;Kim, Soon-Ok
    • Journal of Families and Better Life
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    • v.30 no.2
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    • pp.101-120
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    • 2012
  • This research was conducted in order to find out the effects of boys' self-control, their parents' behaviors and marital conflict on boys' aggression. Subtypes of aggression in the present research consist of dimensions of the functions and forms (proactive-overt, proactive-relational, reactive-overt, reactive-relational). The participants of this study were 237 boys in the fifth and sixth grades in elementary schools located in Seoul and Gyeonggi province. The questionnaires were derived and modified from Lee Hong (2009) for boys' aggression, from Ju So Young and Lee Yang Hee (2008) for boys' self-control, from Jun Joo Ram (2008) and Heo Seung Yeon (2009) for maternal behaviors and from Kang Na Jung (2008) for marital conflict. In order to grasp the general characteristics of the participants, frequency and descriptive statistics were used. Also, Pearson's correlation was applied to the relationships amomg boys' self-control, marital behaviors and marital conflict on boys' aggression. Lastly, the variables that can predict boys' aggression were analyzed through multiple regression analysis by SPSS 19.0. The major results of this study were as follows. This research showed that this model fit well for boys. To summarize the important results, what is interesting in the present study is the effect of the mother's role in rearing their sons. It was found that mothers' criticism, negative behaviors, and excessive interference can cause boys' high level of aggressiveness. Also, having parents who fight frequently was strongly associated with boys' relational aggression. An interesting finding is that the mother's support influenced boys' reactive-overt aggression. Lastly, boys' self-control was highly associated with boys' proactive-relational aggression. This research may contribute to understanding boys' aggression' subtypes. To that end, the current results suggest that the dimensions of the functions and forms may be a useful tool in an effort to inform developmental theory and intervention. Also, this research may provide guidance for the resolution of problems caused by boys' aggression. Lastly, it was found that self- control training and parental education programs might prove beneficial for helping aggressive boys to overcome their aggressive impulses.

Development of an ACL Anchor: Effects of the Design Parameters on the Performance of a New Anterior Cruciate Ligament Fixation Device

  • Kim, Jong-Dae;Oh, Chae-Youn;Kim, Cheol-Sang
    • Journal of Biomedical Engineering Research
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    • v.29 no.2
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    • pp.132-138
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    • 2008
  • We investigated the biomechanical properties of a newly designed self-expansion type anterior cruciate ligament (ACL) anchor. The ACL anchor consists of the ring section giving the elastic force, the wedge for maintaining in contact with the femur tunnel wall and the link suspending hamstring graft or artificial ligament. The main design parameters that determine the performance of this device were the expansion angle (${\theta}$) and the thickness ($t_R$). The Ti6Al4V anchors were heated after inserting in a jig for 1 hour at $800^{\circ}C$ in a protective argon gas atmosphere and allowed to cool to room temperature in the furnace. In order to investigate the influence of the expansion angle and the thickness of the ring on the biomechanical properties of the anchor, the maximum pull-out load, stiffness and slippage of the ACL anchor were measured using the pull-out tester, and statistical analyses were also executed. The present results showed that the design parameters gave a significant effect on the performance of the self- expansion type of anchor. The pull-out load of the ACL anchors significantly increased as the thickness of the ring section was increased, having a similar trend for both expansion angles. The ACL anchor showed about 2.5 times higher values of the pull-out load than that of the minimum load (500N)required for the "accelerated rehabilitation". The optimum ${\theta}$ and $t_R$ values of this ACL anchor were suggested to have sufficient resistance against the pull-out force, high stiffness and relatively low slippage after ACL reconstruction.

Reliability of the Neck Pain and Disability Scale in Neck Pain Patients (경통 환자들을 위한 Neck Pain and Disability Scale의 신뢰도 연구)

  • Shin, Won-Seob;Lee, Eun-Woo;Jung, Kyoung-Sim;Lee, Suk-Min;Chung, Yi-Jung
    • Physical Therapy Korea
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    • v.15 no.1
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    • pp.77-85
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    • 2008
  • The self-report measure is a useful tool for evaluating self-recognized disability and difficulty in daily living activities. Although many studies and clinics used the Neck Pain and Disability Scale (NPDS) for measuring neck pain and functional impairment, there has not been much adaptation of this for use with Korean patients. The purpose of this study was to establish the reliability and validity of NPDS among Korean neck pain patients. Fifty-five subjects (32 males, 23 females) with neck pain enrolled in this study. They completed standardized self-administered questionnaires. The NPDS measures pain intensity; its interference with vocational, emotional, recreational, social, and functional aspects of living; and the presence and extent of associated factors. Reliability was determined by the intraclass correlation coefficient (ICC) and Cronbach's alpha for internal consistency. Validity was examined by correlating the NPDS scores to the Visual Analog Scale (VAS) score. The test-retest reliability of the translated versions of the NPDS was good ICC (2,1)=.86 (95%CI .76~.92). Cronbach's alpha value for NPDS was found to be .93, and this was statistically significant (p<.05). The criterion-related validity coefficient was .79 (p<.Oll. We conclude that the Korean version of NPDS has been shown to be a reliable and valid instrument for the assessment of neck pain. Successful linguistic and cultural translation will admit appropriate cross-cultural comparison for clinical analysis. Therefore, this study can be expected to be used as an adequate evaluation scale for neck pain related studies and treatments.

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The Envy and Suffering: Feelings of Characters Appearing in Self-Development Narrative - Focusing on a Soap Opera (시기심과 고통: 자기계발 서사에 나타난 감정 연구 - 막장드라마 <아내의 유혹>을 중심으로 -)

  • Park, Suk-Ja
    • Cross-Cultural Studies
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    • v.46
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    • pp.21-42
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    • 2017
  • This study aims at analyzing the trend of feeling under the neo-liberalism era through the soap operas. In particular, this article focuses on 'envy'. Unlike jealousy, envy is the feeling of comparison appearing in people in similar circumstances that is displayed within the dual relation with its characteristic of having dynamics on the fortune (victory) of the other party for an unpleasant feeling, denial and interference. However, under the neo-liberalistic order with unlimited competition as its characteristic, 'envy' has the tendency to discourse with its passion of subjects participating in the limited share of competition. This begins in 'envy' under a soap opera to lead to competition to reproduce as the drama to dream of success for self-development. Under the circumstances, the feeling or behavior of characters not showing the general pattern but to individualize with the envious behavior of evil characters to turn away from the structural context for characters of issue of suffering originated within. For example, the soap opera imagines with 'envy' for the feeling of characters to reproduce the neo-liberalistic subject in darkness as well as to transfigure the suffering or context encountered by the characteristics to present the issues.

Establishment and Performance Test of Wireless Communication Network for Train Control using Wireless Mesh Network(WMN) (무선 메쉬 네트워크를 이용한 열차무선통신망 구축 및 성능시험)

  • Cho, Dong-Rae;Yoo, Sung-Ho;Kim, Ja-Young;Park, Chae-Jung;Lee, Sung-Hoon
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.2787-2794
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    • 2011
  • A mesh node, a component of a mesh network, is connected with the network by dynamic routing using routing protocol and collects the information of adjacent or connected mesh nodes for its self-management and settings. Also, it relays packets between the mesh nodes and provides AP(Access Point) with its corresponding functions based on IEEE 802.11 a/b/g for clients' access to the network. In this paper, the study focused on the design and performance tests of Wireless Mesh Network(WMN) which is applied to the wireless communication network for the CBTC(Communications Based Train Control) system. The WMN was established on a K-AGT test-line (Kyeongsan city, Gyeongsangbuk-do), and to verify the applicability, its operation and performances are checked by measuring the data throughput, delay latency, quality measurements such as transmission loss, radio interference and path recovery and setup between the on-board and wayside.

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The Behavior of Fresh Concrete to Pass between Bars (굳지 않은 콘크리트의 간극통과거동)

  • 오상균
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2002.05a
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    • pp.97-102
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    • 2002
  • The ability to pass between bars is one of the most important performance of self-compacting concrete or high-flowability concrete since it determines the final filling capacity which influences the strength and durability of hardened concrete in structure. Therefore it has been evaluated by many researchers using different kinds of testing apparatuses. The assessments of passing ability, however, differ largely according to the style, the dimension and the criteria in apparatuses, and the value obtained from one apparatus cannot be converted those of the others. There needs a rheological approach to the better understanding of the passing behavior of fresh concrete between reinforcing bars, where the flow velocity of concrete becomes slow and the blockade sometimes occurs due to the interference between aggregates and reinforcing bars. Experimental works were conducted to clarity the effects of the clearance between reinforcing bars, the volume of aggregate and the rheological properties of matrix on the behavior from the rheological point view and showed the rational mix proportioning of concrete.

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Some Philosophical Considerations for Autonomy of Nursing Care (간호의 독자성을 위한 철학적 고찰)

  • 최남희;이남희
    • Journal of Korean Academy of Nursing
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    • v.18 no.1
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    • pp.19-25
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    • 1988
  • To ensure the autonomy of nursing care aetivies is one of the major and most interesting issues in the field of nursing. The pertaining autonomy demands the nurse to make decisions of her or his own with out interference and free of help from other sides of health care agency. The whole process of autonomous nursing behavior should be judged and conveyed by the nurse only on the basis of the internal factors of her care to solve the problems of the client's disorder in health. Truth of nursing science and relevence of nursing conduct depend on our construction of internal basis and establishment of self-sufficient reference system. The information for efficient decision-making at the scene of nursing can only be supplied by a systematic body of nursing science consisting of true or properly corroborated propositions. The science of nursing can be autonomous when we have framework of explanation, independently of other sciences and the behavior of nursing care can factually be independent of and peculiar to that of other but similar fields only when the science of nursing is correspondently autonomous.

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