• 한국자기학회지
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• 제5권5호
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• pp.753-757
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• 1995

Systematic studies on the crystal structure and magnetic properties of light rare earth element(RE) compounds with Pb, $REPb_{2}$, have been carried out. Their crystal structure has been identified to be a $MoSi_{2}$-type. The values of the effective magnetic moment for $CePb_{2},\;PrPb_{2}\;and\;NdPb_{2}$ are respectively very close to the theoretical values of $RE^{3+}$. These three compounds are antiferromagnetic and exhibit a metamagnetic transition. The magnitude of the Neel temperature is proportional to two-thirds of the de Gennes factor. The magnetic entropy change for $NdPb_{2}$ is contrast to the value for $CePb_{2}$ heavy-fermion compound, comparable to the theoretical value. The magnetic contribution to the temperature dependence of resistivity for $PrPb_{2}$ is given by a form of -lnT in a wide temperature range, implying the Kondo system in analogy with $Cepb_{2}$.

• 천문학회지
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• 제51권6호
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• pp.185-195
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• 2018

Galaxy clusters are known to host many active galaxies (AGNs) with radio jets, which could expand to form radio bubbles with relativistic electrons in the intracluster medium (ICM). It has been suggested that fossil relativistic electrons contained in remnant bubbles from extinct radio galaxies can be re-accelerated to radio-emitting energies by merger-driven shocks via diffusive shock acceleration (DSA), leading to the birth of radio relics detected in clusters. In this study we assume that such bubble consist primarily of thermal gas entrained from the surrounding medium and dynamically-insignificant amounts of relativistic electrons. We also consider several realistic models for magnetic fields in the cluster outskirts, including the ICM field that scales with the gas density as $B_{ICM}{\infty}n^{0.5}_{ICM}$. Then we perform time-dependent DSA simulations of a spherical shock that runs into a lower-density but higher-temperature bubble with the ratio $n_b/n_{ICM}{\approx}T_{ICM}/T_b{\approx}0.5$. We find that inside the bubble the shock speed increases by about 20 %, but the Mach number decreases by about 15% in the case under consideration. In this re-acceleration model, the observed properties of a radio relic such as radio flux, spectral index, and integrated spectrum would be governed mainly by the presence of seed relativistic electrons and the magnetic field profile as well as shock dynamics. Thus it is crucial to understand how fossil electrons are deposited by AGNs in the ICM and how the downstream magnetic field evolves behind the shock in detailed modeling of radio relics.

• 한국균학회지
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• 제25권1호통권80호
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• pp.10-19
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• 1997

무우품종(Raphanus sativus L.) Saxa Nova에 시들음병을 일으키는 Fusarium oxysporum f. sp. raphani (FOR)에 대해 저항성을 증가시켜 방제효과를 얻기 위하여 식물성장을 증진시키는 것으로 알려진 Pseudomonas florescens WCS374 (WCS 374), P. putida RE10 (RE10) 및 Pseudomonas sp. EN41S (EN415)을 병원균처리 토양에 단독 또는 혼합처리하여 4주간 폿트배양한 후 무우에 나타나는 외부 및 내부병징을 조사하여 처리세균에 의한 병억제 효과를 측정하였다. 내부 및 외부병징으로 대조구는 각각 46.5% 및 21.1%를 나타내었고, RE10처리는 내외병징이 각각 12.2%와 7.8%로 발병이 억제됨을 알 수 있었다. 그러나 발병억제력이 높다고 알려진 WCS374는 내외 병징이 각각 45.6%와 27.8%로 나타났다. 한편 RE10균주를 WCS374 또는 EN415 균주와 혼합하여 처리할 경우 내외 병징이 10.0-22.1% 정도이었고 EN415와 혼합처리하면 7.8-20.2%의 병징을 나타낸다. FOR의 뿌리점유율은 뿌리에서 $2.4-5.1{\times}10^3/g$였고 토양내 분포수는 $0.7-1.3{\times}10^3/g$이었다. 대조구는 뿌리에서 $3.8{\times}10^3/g$였으며 RE10의 처리는 $2.9{\times}10^3/g$로 분포수가 적었고, 3종 세균의 혼합처리는 $5.1{\times}10^3/g$으로 많이 관찰되었으나, 처리간에 통계적 차이는 없었다. 토양에서 관찰된 FOR은 부리부분 보다 그 분포 수가 적었다. 처리된 3가지 세균은 뿌리에서 $2.3-4.0{\times}10^7/g$ 범위이고, 토양에서는 $0.9-1.8{\times}10^7/g$으로 뿌리에서 관찰된 수 보다 적게 분포하였다. 뿌리부분에서 대조구나 RE10의 처리토양은 형광성 Pseudomonas spp.의 분포수가 적고 처리간에는 통계적 차이를 나타냈으나, 토양조사에서 이세균은 큰 차이를 나타내지 않았다. 뿌리에 처리된 세균과 FOR의 분포수는 토양에 처리된 것과 대조하였을 때 많았으며, 이 실험 에 사용된 RE10과 EN415은 Fusarium시들음병에 대한 기주의 저항성을 유도하는 것으로 생각된다.

• 한국결정성장학회지
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• 제8권1호
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• pp.18-28
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• 1998

초크랄스키 대류에서의 온도진동 억제에 대한 실험 및 수치해석 연구가 수행되었다. 결정봉 회전 가속화기법을 초크랄스키 성장에 적용시키기 위해 결정봉 회전가속도를($\Omega=\Omega_0(1+A sin 2{\pi}ft/t_p)$)로 변화시켰다. 여기서 A는 가진증율, f는 가진주파수인자를 나타낸다. 제어이전에 나타나는 고유한 온도진동 주기 ($t_p$)를 근거하여, 무차원 혼합대류인자($0.217{\leq}Ra/PrRe^2{\leq}1.658$)에 온도진동 감소율을 조사하였다. 또한 제어인자 A와 f에 대한 효과를 조사하였다. 용융유동 내의 온도진동 억제 현상을 이해하기 위해 자오면상에 나타나는 온도 및 와도분포가 면밀히 검토되었다.

• 한국안전학회지
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• 제21권3호
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• pp.1-7
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• 2006

Nowadays, out of other transmission parts, the sleeve is getting more and more important part for exact and smooth shifting from gear ratio change whenever drivers are needed. To exact and smooth shifting when drivers are needed, all the parts connected with gear shifting should be machined exactly and having dimensions designers are intended. Especially, in case of the sleeve that the most important functional part to shift from gear ratio change that drivers are intended, it needs high precision grade and quality in both sides runout and outer dia runout as well as inner spline small dia & large dia. Because it's assembled with the synchro hub spline and shifted directly with the mating cone. So, it should be applied the hear treatment(hereinafter referred to H.T.M.T) to prevent the friction and percussion loss from shifting with mating cone. At this time, the deformation problems are raised from almost H.T.M.T. process and it makes the inferior part.

• 보건의료산업학회지
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• 제13권2호
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• pp.15-25
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• 2019

Objectives: Guardians of patients have a great deal of influence on decision-making in the course of care in Korea. The purpose of this study was to explore the effect of nursing service satisfaction on hospital re-use intention in the guardians of patients admitted to comprehensive nursing care units. Methods: The survey was conducted on 151 guardians of patients hospitalized in comprehensive nursing care units of two general hospitals for four months beginning in September 2017. The data were analyzed with descriptive statistics, t-tests, Pearson's correlation coefficient, and multiple regression analyses using SPSS/Win 21 software. Results: Nineteen percent of variance in hospital re-use intention was accounted for by reliability (t=3.31, p=.001), empathy (t=2.49, p=.014), and recommendations from others (t=2.49, p=.014). The explanatory power was significant (F=13.06, p<.001). Conclusions: To promote hospital reuse, nurses need to improve the quality of their nursing services. Emphasis should be on reliability and empathy among nursing service components. It is also necessary to consider ways to encourage guardians who used hospitals to recommend them to their acquaintances.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.276-277
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• 2006

1mm-thick BLT ceramics were sintered in accordance with a bulk ceramic fabrication process. AII XRD peaks detected in the sintered ceramics were indexed as the Bi-layered perovskite structure without secondary phases. Density was increased with increasing the sintering temperature up to $1050^{\circ}C$ and the maximum value was about 98% of the theoretical density. The remanent polarization (2Pr) value of BLT ceramic sintered at $1050^{\circ}C$ was approximately $6.5\;{\mu}C/cm^2$ at the applied voltage of 4.5 kV. The calculated electromechanical coupling factor ($k_t$) of it was about 5% and the mechanical quality factor (Qm) was about 2200. From these results, a BLT ceramic target for pulsed laser deposition (PLD) system was successfully fabricated.

• 대한수학회보
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• 제46권6호
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• pp.1091-1097
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• 2009

In this paper, we investigate the extensions of generalized stable rings. It is shown that a ring R is a generalized stable ring if and only if R has a complete orthogonal set {e$_1$, . . . , e$_n$} of idempotents such that e$_1$Re$_1$, . . . , e$_n$Re$_n$ are generalized stable rings. Also, we prove that a ring R is a generalized stable ring if and only if R[[X]] is a generalized stable ring if and only if T(R,M) is a generalized stable ring.

• 한국초전도ㆍ저온공학회논문지
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• 제24권3호
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• pp.41-46
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• 2022

The superconducting properties of high temperature superconducting (HTS) GdBCO coated conductor (CC) tape (Ag/GdBCO/Buffer-layers/Stainless Steel) were investigated, specifically a series of samples prepared by vacuum heat treatment (200℃ to 600℃), using a Quantum Design PPMS-14. The critical current density J_c value was obtained by applying the modified Bean model to the irreversible magnetization ∆M_irr(H) data which was estimated from the magnetization M(H) loop. The reduction rates of lnJ_c and T_c values according to the increase of the vacuum annealing temperature T_an were d(lnJ_c)/dT_an = - 0.016 A/(cm²∙℃) and dT_c/dT_an = - 0.24, respectively. We examined the effect of recovery temperature T_re (475℃ to 700℃) and recovery duration time t (0.5 h to 24 h) on the restoration of previously completely lost superconductivity in samples that subsequently received heat treatment in an O₂ gas flow space. All samples were fully restored to superconductivity by heat treatment in an O₂ gas flow space. The recovery temperatures T_re (475℃ to 700℃) and recovery duration times t (0.5 h to 24 h) were both independent of the superconductivity recovery characteristics.

• 한국식품영양과학회지
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• 제38권5호
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• pp.636-643
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• 2009

본 연구는 제주를 방문한 관광객들의 제주향토음식의 선택속성 요인이 제주 관광객의 고객행동에 어떠한 영향을 미치는가를 알아보기 위한 연구로 통계패키지 SPSS+/WIN 12.0을 이용하여 제주향토음식선택속성의 요인들이 고객만족, 재방문, 구전 의도에 미치는 영향을 파악하기 위해 다중회귀분석을 실시하였다. 연구결과 제주향토음식선택속성요인이 고객행동에 미치는 영향을 살펴본 결과 유의수준(p<0.05)에서 통계적으로 유의한 영향력을 가진 요인은 만족도에는 본질적 요인이 회귀계수가 0.476, t값이 5.198로 영향력을 나타내는 것으로 나타났으며, 다음으로는 부수적 요인이 회귀계수 0.232, t값이 2.808, 감각적(오감) 요인이 회귀계수 0.165, t값이 2.013의 순으로 나타났다. 재방문에는 본질적 요인이 회귀계수가 0.413, t값이 3.540으로 영향력을 나타내는 것으로 나타났으며, 다음으로는 메뉴 구성적 요인이 회귀계수 0.228, t값이 3.118, 부수적 요인이 회귀계수 0.218, t값이 2.643의 순으로 나타났다. 긍정적인 구전에는 부수적 요인이 회귀계수가 0.273, t값이 2.555로 영향력을 나타내는 것으로 나타났으며, 다음으로는 감각(오감)적 요인이 회귀계수 0.264, t값이 2.238, 본질적 요인이 회귀계수 0.237, t값이 2.230, 메뉴.구성적 요인이 회귀계수 0.161, t값이 2.167의 순으로 나타났다. 따라서 본 연구는 제주를 방문한 관광객의 제주향토음식에 대한 고객행동(고객만족, 재방문, 긍정적인 구전)에 미치는 영향은 향토 문화성은 고객의 행동에 모두 영향을 미치지 못하는 것으로 나타났는데 이는 직업이 학생이며 연령대가 $20{\sim}29$세가 주를 이루고 있는 인구통계적 특성에서 오는 것으로 사료되며, 본질적 요인과 부수적 요인은 고객행동인 고객만족, 재방문, 긍정적인 구전에 모두 영향을 미치는 것으로 나타났다. 특히 음식선택에 대한 본질적 요인은 고객행동에 전반적으로 영향을 크게 미치는 것으로 나타났다.