• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.3207-3209
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• 2000

X-ray CT(Computed Tomography) has been a good modality for non-invasive diagnosis and recently, Conventional CT has been replaced rapidly with Spiral CT in recent. In X-ray CT, spiral scanning has various advantages such as better image quality, reduced scan time (in a single breath-hold), a lower x-ray dose. But, it requires very fast and high performance image processing system to reconstruct slice images from spiral scanning. This paper describes the fast image reconstruction techniques with filtered back projection from the viewpoints of fast algorithm as well as hardware implementation for real-time imaging.

• 대한치과보철학회지
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• 제52권2호
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• pp.105-112
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• 2014

연구 목적: 이 연구의 목적은 임플란트 식립 초기 수회의 의원성 동요가 최종 골결합에 미치는 영향을 확인하는 것이다. 연구 재료 및 방법: 순수한 티타늄(Grade IV) 으로 직경 3.75 mm, 길이 8 mm의 실험용 임플란트를 제작한 후, 하방 4 mm에 RBM 표면처리($MegaGen^{(R)}$: Ca-P)를 하였다. 임플란트의 하부만 골에 식립되었으며 비침하시켰다. 수술은 3.5 kg이상의 토끼의 좌우 경골의 단층 치밀골에 각각 2개씩 130개를 통상적인 방법으로 식립하였다(Female, New Zealand White). 비틀림 제거 간격에 따라, 다음과 같은 13개의 군으로 나누었다; Group I (1일), Group II (1일 + 2일), Group III (1일 + 2일 + 3일), Group IV (1일 + 2일 + 3일 + 4일), Group V (2일), Group VI (2일 + 4일), Group VII (2일 + 4일 + 6일), Group VIII (2일 + 4일 + 6일 + 8일), Group IX (4일), Group X (4일 + 7일), Group XI (4일 + 7일 + 10일), Group XII (4일 + 7일 + 10일 + 14일), 그리고 대조군. 대조군은 식립 후 8주의 치유기간을 준 후 최종 비틀림 제거력을 측정하였다(Mark-10, USA). 실험군은 각각의 조건에 맞추어 1회에서 4회에 걸쳐 비틀림 제거력을 측정하였다. 비틀림 제거력을 측정한 이후에 대체적으로 임플란트를 측정 전의 위치로 재위치시켰다. 모든 실험군에서 임플란트 식립 후 8주간의 치유기간을 준 다음 최종 비틀림 제거력을 측정하여 대조군, 각 실험군의 1, 2, 3, 4번째 비틀림 제거력과 비교하였다. 결과: 실험군 간에 최종 비틀림 제거력을 비교한 결과에서, XII군을 제외한 실험군의 비틀림 제거력은 대조군과 유의할만한 차이를 보이지는 않았다. 그리고 실험 I군과 II군의 값은 VI, VIII, X, XI, XII군의 값보다 유의하게 높게 나타났다. 그리고 III, IV, V군은 XI, XII군의 값보다 유의하게 높게 나타났다. 각 실험군간 비틀림 제거력 비교에서, 최종 비틀림 제거력은 VIII, X, XI, XII군을 제외한 모든 군에서 높게 나타났다. 결론: 충분한 치유기간이 주어진다면, 토끼에게 임플란트 식립 후 매우 이른 초기에 지대주에 가해지는 약간의 동요는 임플란트 골결합에 영향을 미치지 않았다.

• 대한소아치과학회지
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• 제31권2호
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• pp.159-168
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• 2004

자일리톨 껌 저작에 의해 어린이들의 유치우식증 예방효과를 평가하기 위하여 3개 어린이집에서 만 $5{\sim}6$세 어린이 123명을 최종 선정하였다. 자일리톨 껌을 씹는 군(42명), 솔비톨 껌을 씹는 군(42명) 그리고 아무런 조치도 취하지 않은 대조군(39명)으로 나누어 12개월 동안 하루 5회씩 껌을 저작하게 한 다음 구강검사와 우식활성 검사를 통해 유치우식증 예방효과를 비교 분석 하였다. 12개월 동안 대조군 어린이들에서는 dfs index가 5.19개면 증가하였고 솔비톨 군에서는 2.96개면이 증가한 반면 자일리톨 군에서는 2.62개면이 증가하여 대조군에 비해 자일리톨 군은 47.1%가 감소하였고 솔비톨 군에서는 43.6%가 감소한 것으로 나타났다. Dentocult-SM strip 검사 및 site strip 검사 결과 모두에서 대조군에 비해 자일리톨 껌과 솔비톨 껌을 씹은 군의 아동들에서 우식활성도가 공히 감소되었다 따라서 본 연구와 같은 집중적인 자일리톨 껌의 저작 사업은 대상자들과 부모들의 사업에 대한 호응도가 높았고, 사업 시행이 다른 국책 구강보건사업에 비해 용이하였으며 특히 유치우식증 예방적인 측면에서 효과적인 것으로 나타났다.

• Journal of applied mathematics & informatics
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• 제10권1_2호
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• pp.167-174
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• 2002

A group G is said to be (l, n, n)-generated if it is a quotient group of the triangle group T(p,q,r)=(x,y,z|x$\^$p/=y$\^$q/=z$\^$r/=xyz=1). In [15], the question of finding all triples (l, m, n) such that non-abelian finite simple groups are (l , m, n)-generated was posed. In this paper we partially answer this question for the sporadic group He. We continue the study of (p, q, r) -generations of the sporadic simple groups, where p, q, r are distinct primes. The problem is resolved for the Held group He.

• Environmental Analysis Health and Toxicology
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• 제22권1호
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• pp.73-82
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• 2007

Six week-old ICR mite which were divided into four groups including NC, RC, RR and RS were injected with sun ginseng (RS), red ginseng (RR) and saline (RC) intraperitonedlly as an amount of 60 mg/g body weight at 1 hour, 12 hours and 36 hours before the irradiation of high-energy X-ray and the mire were sacrificed at three and a half days after the irradiation. The RS group were significant increase in the weight of spleen (p<0.01) and the numbers of jejunal crypt cells (P<0.01), WBC (p<0.05), lymphocytes (p<0.05) and neutrophils (p<0.05) in comparison with the RC group. The RR group were significant increase in the numbers of jejunal crypt cells (p<0.001), WBC (p<0.05) and neutrophils (p<0.05) in comparison with the RC group. The RS group exhibited a more increase in the weights of spleen and thymus and the numbers of jejunal crypt cells and all items of hematological examination than the RR group. The values of ALT (alanine transaminase) and AST (aspartate transaminase) were significantly elevated (p<0.05) by radiation and they were significantly decreased (p<0.05) in the RS group to the values of the NC group. Taken together the above results, sun ginseng demonstrated a jejunal crypt survival effect, the protective effects on hepatocytes and immune and hematopoietic cells in mice irradiated with high-energy X-ray, and those radiation protective effects were a little higher in comparison with red ginseng.

• 대한간호학회지
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• 제34권3호
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• pp.440-448
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• 2004

Purpose: This study was to evaluate the effects of a physical activity reinforcement program on exercise compliance, depression, and anxiety in continuous ambulatory peritoneal dialysis(CAPD) patients. Method: A nonequivalent control group with a pre-post test was designed. Data collection was done from December, 2002 to June, 2003 at a hoapital. The degree of depression and anxiety of the patients was assessed by the score of SCL-90-R, and exercise compliance was measured by exercise period, frequency, time and intensity. The experimental group was composed of 19 participants who were educated based on an exercise education protocol and carried out walking exercises two to four times a week after hearing verbal persuasion biweekly through the telephone or a face-to-face interview for 12 weeks, while 17 participants in control group received no intervention. Result: 1. The experimental group showed significant improvement in self-efficacy of exercise compliance (U=79.00, p=.01), exercise period ($x^2$=20.84, p=.00), exercise frequency ($x^2$=9.03, p=.0l), exercise time ($x^2$=9.03, p=.0l) and exercise intensity ($x^2$=11.09, p=.00) compared to those of the control group. 2. The experimental group showed a lower depression score (U=84.50, p=.01) than the results of the control group. 3. However, there were no changes in anxiety level compared to the control group. Conclusion: The physical activity reinforcement program was found to have an effect on exercise compliance and the depression score of CAPD patients. The results provided evidence for the importance of physical activity and verbal persuasion in CAPD patients.

• Toxicological Research
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• 제11권2호
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• pp.205-213
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• 1995

This study was undertaken to investigate the effects of organic solvents on xenobiotic metabollzing enzyme system in vivo by meaas of experimental conditions i.e. (1) single group which was treated by benzene (B), toluene (T) and xylene (X), respectively, (2) combination group which was treated by mixture of benzene+toluene (BT), benzene+xylene (BX), and toluene+xylene (TX), respectively, (3) mixture group which was treated by benzene+ toluene+xylene mixture (M), and to interpreat the interaction between the organic solvents metabolizing enzymes. 1. The contents of cytochrome P-450 in liver microsomes were increased (p < 0.01) in organic solvents treated groups, and the contents of cytochrome P-450 were increased by following order of B < T < M < BT=BX < X < TX. 2. The activity of cytochrome P-450 dependent AHHase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the activity of AHHase was increased by following order of B < T < BT=BX=TX=xylene < M. 3. The activity of NADPH P-450 reductase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the order of M < combinated group < X < T

• 공업화학
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• 제28권2호
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• pp.230-236
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• 2017

본 연구에서는 콜레스테릭 액정상 유도를 위하여 아이소소바이드기를 가지고 있으며, 액정상 전이온도의 조절을 위하여 메틸렌기를 포함하고 있는 액정고분자들을 합성하였고, 합성된 액정고분자 내의 아이소소바이드기의 함량과 메틸렌기의 위치가 액정고분자의 물성에 미치는 영향이 조사되었다. 합성된 모든 고분자들 중, 주사슬에 메틸렌 유연격자를 가진 고분자(MnHI-x)가 곁사슬에 메틸렌 유연격자를 가진 고분자(SnBI-x)들보다 더 높은 용융전이온도와 열안정성을 나타내었다. 합성된 모든 고분자들은 양방성 액정상을 나타냈으며, 콜레스테릭 액정상 유도체로써 아이소소바이드 함량이 10몰%인 고분자는 네마틱상을, 20몰% 이상의 고분자들은 콜레스테릭 액정상 또는 카이랄 스멕틱상을 형성하였다. 이로써, 아이소소바이드기가 콜레스테릭 액정상 유도체로써의 역할을 하였음을 알 수 있다.

• 한국초전도ㆍ저온공학회논문지
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• 제7권2호
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• pp.7-10
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• 2005

The magnetic properties of a series of both annealed (biaxially textured) and as-rolled (non-textured) Ni-xW alloy tapes with compositions x = 0,1,3, and 5 at.$\%$, were studied. Characterization methods included XRD analyses to investigate the biaxial cube texturing of the annealed Ni-W alloy tapes and studies of the magnetization M for both annealed and as-rolled Ni-W alloy tapes. Both the isothermal mass magnetizations M(H) of a series of samples at different fixed temperatures and M(T) in fixed field, employing a PPMS-9 (Quantum Design), were measured. The Ni-W alloys have shown much reduced ferromagnetism as W-content x increases. Both the saturation magnetization Msat and Curie temperature Tc decrease linearly with W-content x, and both Msat and Tc go to zero at critical concentration of Xc - 9.50 at. $\%$ W.

• Kyungpook Mathematical Journal
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• 제55권2호
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• pp.251-258
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• 2015

Let $\mathcal{A}$ be a unital $C^*$-algebra, a, x and y are elements in $\mathcal{A}$. In this paper, we present the expression of the Moore-Penrose inverse and the group inverse of a-$xy^*$ under the conditions $x=aa^+x,y^*=y^*a^+a$, respectively.