• 제목/요약/키워드: scale effect

검색결과 8,398건 처리시간 0.04초

지도축척의 영향에 따른 하천형태학적 특성연구 (A study on stream morphological characteristics according to effect of Map Scale)

  • 안상진;조용진
    • 한국농공학회지
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    • 제23권1호
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    • pp.64-74
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    • 1981
  • The stream morphological characteristics of watershed have important influence upon the analysis of runoff. In this study, the effect of the map scale on the stream morphological characteristics was used on the data taken from 15'(1:50, 000) and 7'30"(1 :25,000) topographic maps which could cover the whole Miho River basin This basin are the first tributary of the Geum. River. Otherwise, the longitudinal stream bed profile was calculated by Yang's theoretical stream bed profile, equilibrium profile and actual profile. In the result of this investigation the conclusion is that the resultant relationship obtained from different topographic maps in the scale on the same stream system has come upon the same result as the stream morphological characteristics. Therefore, the great amount of time and effort can be saved in studing the stream morphological charecteristics by using the 15' instead of the 7'30"map system excluding the first order streams.

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측벽효과를 고려한 개구부 분출화염 거동 연구 (Study on the Ejected Plume from Opening Regarding Side-wall Effect in Fire)

  • 정재군;신이철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.219-220
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    • 2016
  • The behavior of fire plumes has not yet been clearly identified for cases where sidewalls are installed near an opening in an unconfined space. In this research, we aim to quantitatively identify the effects on fire spread when sidewalls are located on both sides of an opening. Specifically, we focus on the effects on the fire plume of the relation between the location of sidewalls and the opening, and carry out a scale-model experiment to devise a flame height model and to evaluate the temperature distribution along the central axis of the flame.

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소염 거리에 근접하는 소형 연소실 환경에서의 연소특성 (Combustion Characteristics in Small Combustion Chamber Size about Quenching Distance)

  • 이대훈;최권형;권세진
    • 한국연소학회지
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    • 제5권2호
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    • pp.63-68
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    • 2000
  • Combustion phenomenon in scale-downed combustor is investigated. As the combustor scale decreases surface to volume ratio increases and chamber size approaches quenching distance. As the combustor scales down surface to volume ratio increases resulting increased heat loss. And this heat loss can affect quenching and instability of the flame. To investigate this effect plastic mini combustor is made. Stoichiometricaly premixed Hydrogen / air gas is used as fuel. Initial chamber pressure and chamber size are varied and the effects are evaluated. Peak pressure decreased with the decrease in chamber height. As initial chamber pressure decreases peak pressure decreases and this change is more important than scale down effect till the chamber height of 1mm. With this result and further information following the experiments design parameter for micro engine can be established.

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Free vibration investigation of FG nanoscale plate using nonlocal two variables integral refined plate theory

  • Balubaid, Mohammed;Tounsi, Abdelouahed;Dakhel, B.;Mahmoud, S.R.
    • Computers and Concrete
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    • 제24권6호
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    • pp.579-586
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    • 2019
  • In this research paper, the free vibrational behavior of the simply supported FG nano-plate is studied using the nonlocal two variables integral refined plate theory. The present model takes into account the small scale effect. The effective's properties of the plate change according to the power law variation (P-FGM). The equations of motion of the system are determined and resolved via Hamilton's principle and Navier procedure, respectively. The validity and efficiency of the current model are confirmed by comparing the results with those given in the literature. At the last section, several numerical results are presented to show the various parameters influencing the vibrational behavior such as the small-scale effect, geometry ratio, material index and aspect ratio.

침도침 시술을 통한 요추추간판탈출증 환자 4명의 증례보고 (Four Case of HIVD-Lumbar Spine Patient Treated with Acupotomy)

  • 곽병민;홍권의
    • Journal of Acupuncture Research
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    • 제25권4호
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    • pp.149-156
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    • 2008
  • Objectives : The purpose of this study is to report the effect of acupotomy for patients with Lumbar intervertebral disc Herniation. Methods : We treated Four patients who have HIVD of L-spine with acupotomy. Visual analog scores(VAS) and Oswestry Low-back pain Disabiliby Index(ODI) were compared before-treatment with after-tretment. When the patients is discharged, the satisfaction of acupotomy were graded by Five-point Likert scale. Results : VAS and ODI were decreased at all case. Likert scale point were cheked as grade 4 at all case. Conclusions : This study shows acupotomy has useful effect on HIVD of L-spine.

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Effect of TiC Content on Oxidation Behavior of Sintered WC-TiC-TaC Alloys

  • Tanaka, Hiroki;Mouri, Shigeki;Nakahara, Kenji;Sano, Hideaki;Zheng, Guo Bin;Uchiyama, Yasuo
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.352-353
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    • 2006
  • The effect of TiC content on oxidation behavior of the sintered WC-TiC-TaC alloys with 2 mass% TaC and different TiC amounts of 3-45 mass% was investigated through oxidation tests in air at 973K. As a result of the tests, it was revealed that with increasing TiC content in the alloys, mass changes caused by oxidation and thickness of the scale decreased. Thus, it is considered that the main component of the scales changed gradually from $WO_3$ to $TiO_2$ with increasing TiC content in the alloys, and oxygen diffusion through the scale to the alloys was inhibited gradually.

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TiAl 합금의 고온 산화에 미치는 Fe의 영향 (Effect of Fe on the High Temperature Oxidation of TiAl Alloys)

  • 김미현;이동복
    • 한국표면공학회지
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    • 제33권4호
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    • pp.281-288
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    • 2000
  • To understand the effect of Fe on the oxidation behavior of TiAl alloys, TiAl-(2, 4, 6at% )Fe were oxidized at 800 and 90$0^{\circ}C$ in air. The oxidation resistance of TiAl-Fe alloys increased with increasing an iron content. The scales formed consisted of an outer $TiO_2$ layer, an intermediate $A1_2$$O_3$ layer, and an inner mixed ($TiO_2$+$A1_2$$O_3$) layer, being similar to other common TiAl alloys. But, the scales formed on TiAl-Fe alloys were generally thin compared to those formed on pure TiAl, and contained dissolved iron. Below the oxide scale, an oxygen affected zone was formed. This beneficial effects of Fe on increasing the oxidation resistance and scale adherence of TiAl alloys were attributed to the refinement of oxide grains, increased scale adherence and the enhanced alumina-forming tendency.

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Scale effect of mechanical properties of jointed rock mass: A numerical study based on particle flow code

  • Wang, Xiao;Yuan, Wei;Yan, Yatao;Zhang, Xue
    • Geomechanics and Engineering
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    • 제21권3호
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    • pp.259-268
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    • 2020
  • The synthetic rock mass (SRM) were used to investigate the influence of specimen size on the mechanical properties of jointed rock mass. The SRM were established based on parallel bond model (PBM) and smooth joint model (SJM) and the scaled rock specimens were sampled in two SRMs considering three sampling locations. The research results show that the smaller the initial fracture density is, the greater the uniaxial compressive strength (UCS), elastic modulus (E) is when compared with the same sampling location. The mechanical properties of rock specimens obtained by different sampling methods in different SRMs have different scale effects. The strength of rock specimens with more new cracks is not necessarily less than that of rock specimens with fewer new cracks and the failure of rock is caused by the formation of macro-fracture surface.

전자궁적출술 후 발생한 본태성 떨림에 대한 형방지황탕 가감 투여: 증례보고 (Effect of Modified Hyeongbangjiwhang-tang for essential tremor after total vaginal hysterectomy : Case report)

  • 김보민;조희근
    • 사상체질의학회지
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    • 제30권4호
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    • pp.59-66
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    • 2018
  • Objectives This case reports the effect of Modified Hyeongbangjiwhang-tang for essential tremor after total vaginal hysterectomy. Methods The patient was treated with Modified Hyeongbangjiwhang-tang three times a day. To differentiate other diseases, we took her medical history. And, we used the Verbal Numerical Rating Scale (VNRS) and Gastrointestinal Symptom Rating Scale (GSRS) to assess tremor and gastrointestinal symptoms. Results Treatment with modified Hyeongbangjiwhang-tang resulted in a decrease in the patient's complaints of symptoms. Also, VNRS and GSRS scale were improved. Adverse effects were not observed. Conclusions Modified Hyeongbangjiwhang-tang may be effective for essential tremor after total vaginal hysterectomy.

아버지의 놀이성이 아버지-유아 친밀감에 미치는 영향 - 아버지의 놀이 참여 매개효과를 중심으로 - (The Effect of Father's Playfulness on Father-Child Intimacy - The Mediating Effect of Fathers' Play Participation -)

  • 전혜영;이희선
    • 한국보육지원학회지
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    • 제15권2호
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    • pp.103-123
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    • 2019
  • Objective: The purpose of this study was to examine the mediating role of the father's play participation in the relationship between father playfulness and father-child intimacy. Methods: We conducted a survey of 500 fathers with 3~5 years olds attending kindergartens and located in Seoul and Gyeonggi province. Father's Playfulness Scale, Father's Play Participation Scale, and Father-Child Intimacy Scale were used as data measuring tools. The data collected in this study were analyzed using SPSS 22.0 Program. Results: As a result of examining sub-variables of play participation among fathers, it turned out that mediating effects occurred in physical play, role play, and function play. Conclusion/Implications: The results of this study suggest the necessity of developing a father education program to increase the intimacy between father and child as the role of father becomes increasingly important in the age of co-parenting.