• 한국재료학회지
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• 제23권1호
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• pp.59-66
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• 2013

Opal glass samples having different chemical compositions were synthesized and transparent glass was obtained after melting. The effects of $TiO_2$, $BaF_2$, and $CeO_2$ content on the color of the opal glass were studied by observing images of the opal samples and analyzing the results via ultraviolet visible spectroscopy and color spectrometry. The aesthetic properties of the opal glass were determined by studying the transmittance of visible light in the 400 nm to 700 nm range. The basic chemical composition of opal glass was $SiO_2$ 52.9 wt%, $Al_2O_3$ 12.35 wt%, $Na_2CO_3$ 15.08 wt%, $K_2CO_3$ 10.35 wt%, $Ca_3(PO)_4$ 4.41 wt%, $MgCO_3$ 1.844 wt%, $LiCO_3$ 2.184 wt%, and $TiO_2$ 0.882 wt%. The glass samples were prepared by varying the weight percentage of $TiO_2$, $BaF_2$, and $CeO_2$. The transmittance of visible light was decreased from 95 % to 75 % in the glass samples in which $TiO_2$ content was increased from 0 to 3.882 wt%. In the blue spectrum region, as the content of $TiO_2$ increased, the reflectance value was observed to become higher. This implies that $TiO_2$ content induces more crystal formation and has an important effect on the optical properties of the glass. The opalescence of opal samples that contained $CeO_2$ or $BaF_2$ is stronger than that in the samples containing $TiO_2$. Opal glass samples comprising $TiO_2$ had tetragonal lattice structures; samples including $CeO_2$ as an additive had cubic lattice structures (FCC, $CeO_2$).

• 한국수자원학회논문집
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• 제55권2호
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• pp.111-120
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• 2022

물의 흐름을 제어하는 토양의 기능을 정량적으로 계산하기 위한 방법인 토양수분 메모리(soil moisture memory)는 토양에 도달한 강수가 저장되고 배출되기까지 평균적으로 체류하는 시간을 평가한다. 본 연구에서는 2019, 2020년 한반도 지역에서 강수와 토양수분 위성 기반 모델 산출물을 활용하여 표층(0~5 cm)토양에서의 토양수분 메모리를 산출하고 이를 활용하여 연구지역 내 토양수분 메모리의 시공간적인 분포를 지표면의 경사 및 토양의 특성과 함께 평가하였다. 토양수분 메모리를 특성분석을 위해 강수 사건에 따라 토양수분의 증가를 추적하여 저장 강수율(F_p(f))이라는 새로운 측정 지표를 활용하였다. 강수 발생 초기(3시간 후)에는 산맥을 기준으로 토양 내 저장 강수율이 우선적으로 감소하여 토양수분 메모리의 공간적인 편차가 컸으며 24시간 이후 전반적으로 편차가 감소하였다. 토양 내 저장 강수율은 경사가 증가할수록 감소하는 형태가 뚜렷하게 나타났으며 토양 입자 크기의 구성 비율에 따른 토양 내 수분의 배수 활동에 의한 영향을 확인할 수 있었다. 또한 수리전도도 증감에 기여하는 평균토양수분이 저장 강수율에 미치는 영향을 확인하였다. 본 연구 결과는 강수가 지면에 체류하는 시간에 대한 척도인 토양수분 메모리가 지표의 경사와 토양 특성과 갖는 관계를 규명하고 토양수분의 시공간적 변동성을 이해하는 데 기여할 것으로 기대된다.

• 치과방사선
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• 제28권2호
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• pp.415-433
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• 1998

Digora system is an intraoral indirect digital radiography system utilizing storage phosphor image plate. It has wide dynamic range which allows it to decrease the patient s exposure time and may increase diagnostic ability through image processing (such as edge enhancement, grey scale conversion, brightness change, and contrast enhancement). And also, it can transmit and storage image information. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries between Conventional radiograph and Digora images(unenhanced image, brightness & contrast controlled image, and edge enhanced image). ROC(Receiver Operating Characteristic) analysis, paired t-tests, and F-tests were done for the statistical evaluation of detectability. The following results were acquired: 1. In Grade I lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.953, 0.933, 0.965, 0.978 (p>0.05). 2. In Grade II lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.969, 0.964, 0.988, 0.994. Among theses areas, there was just statistical significance between Diagnostic abilities of Digora edge enhanced image and Conventional radiograph (p<0.05). 3. In the Interobserver variability, the ROC curve areas of Digora edge enhanced image was lowermost in these areas, regardless of the Carious lesion depths. In conclusion, intraoral indirect digital system, Digora system, has the potential possibility as an alternative of Conventional radiograph in the diagnosis of proximal caries.

• 환경영향평가
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• 제21권6호
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• pp.841-857
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• 2012

Preliminary ecological environmental assessments including physico-chemical constituents, water quality, fish fauna analysis, physical habitat health, and ecological health assessment were conducted as a primary step for Jeungchon micro-habitat ecosystem restoration in 2012. Water chemistry analysis of conductivity, dissolved oxygen, chlorophyll-a and etc. indicated that there were no significant differences(p < 0.05) among 6 sites between the headwaters and downstream. Multi-metric model analysis of Qualitative Habitat Evaluation Index(QHEI) showed that brooklets were at "good condition" as a mean QHEI of 158.7(n = 6) and the longitudinal differences of the model values between the sites were minor(QHEI range: 153 - 165). Total fish species and the number of individuals were 12 and 481, respectively, and dominant species were Zacco platypus(49.5%) and Zacco koreanus(36.8%). Tolerance guild analysis showed that the proportion of sensitive species($S_S$) had a negative linear function[$S_S=86.35-0.31(D_H)$; $R^2$ = 0.892, p < 0.01] with a distance from the headwaters, while the proportion of tolerant species($T_S$) had a positive linear function($R^2$ = 0.950, F = 90.28, p < 0.001) with the distance. Trophic feeding guild analysis showed that the proportion of insectivore species($I_n$) had a negative linear function($R^2$ = 0.934, p < 0.01) with a distance from the headwaters, while the proportion of omnivore species($O_m$) had a positive linear function($R^2$ = 0.958, p < 0.001) with the distance. Index of Biological Integrity(IBI) model, based on fish assemblages, showed a "fair condition" as a mean IBI of 23(n = 6), and there was a distinct differences of ecological health between the headwaters(S1 = 30; "good condition") and the downstreams(S6 = 14; "poor condition"). Overall, the preliminary environmental impact assessments suggest that water quality, physical habitat conditions(QHEI model), and ecological health(IBI model) were maintained well, even if the state was not an excellent conditions.

• The Korean Journal of Pain
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• 제33권1호
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• pp.81-89
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• 2020

Background: For children with cleft palates, surgeries at a young age are necessary to reduce feeding or phonation difficulties and reduce complications, especially respiratory tract infections and frequent sinusitis. We hypothesized that dexmedetomidine might prolong the postoperative analgesic duration when added to bupivacaine during nerve blocks. Methods: Eighty patients of 1-5 years old were arbitrarily assigned to two equal groups (forty patients each) to receive bilateral suprazygomatic maxillary nerve blocks. Group A received bilateral 0.2 mL/kg bupivacaine (0.125%; maximum volume 4 mL/side). Group B received bilateral 0.2 mL/kg bupivacaine (0.125%) + 0.5 ㎍/kg dexmedetomidine (maximum volume 4 mL/side). Results: The modified children's hospital of Eastern Ontario pain scale score was significantly lower in group B children after 8 hours of follow-up postoperatively (P < 0.001). Mean values of heart rate and blood pressure were significantly different between the groups, with lower mean values in group B (P < 0.001). Median time to the first analgesic demand in group A children was 10 hours (range 8-12 hr), and no patients needed analgesia in group B. The sedation score assessment was higher in children given dexmedetomidine (P = 0.03) during the first postoperative 30 minutes. Better parent satisfaction scores (5-point Likert scale) were recorded in group B and without serious adverse effects. Conclusions: Addition of dexmedetomidine 0.5 ㎍/kg to bupivacaine 0.125% has accentuated the analgesic efficacy of bilateral suprazygomatic maxillary nerve block in children undergoing primary cleft palate repair with less postoperative supplemental analgesia or untoward effects.

• 동서간호학연구지
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• 제1권1호
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• pp.22-39
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• 1997

Purpose: The purpose of this study is to evaluate the effect of rehabilitation education on the reduction of the stress of family members who have patients suffering from stroke and to find a new way to nurse the patients and their family. Subjects & Methods: The subjects were sixty-one family members with the patients who had been hospotalized in K hospital of oriental medicine from september the 9th, 1996 to september the fourteen, 1996. This study was performed by simulated control group pretest-posttest design; pretest was done on the control group through a questionnaire, counselling and observation while posttest was done on the experimental group 1-2 days after systemic rehabilitation education. To teach the patients and their family, the amended version of a book written by Lee Hae-jin was used as a tool for systemic rehabilitation education. As a method to estimate ADL score, modified Kang's method was applied and ADL score was measured by well-trained technician. As for the tool to estimate the degree of family stress, Choi's method adjusted to this study was applied. In the analysis of the data, social property of the patient and the characteristic of the disease were surveyed in $X^2$ examination to confirm the consistency between the experimental group and the control group. The diffrence in the degree of the stress, which is a dependent factor, was examined by t-test. The difference in ADL score between the experimental group and the control group was examined by t-test. The difference in the degree of the stress according to the general feature of the family with stroke patient, social property of the patients and the characteristic of the disease were surveyed by F examination. The difference in family stress according to the degree of ADL was surveyed by F examination. RESULTS: 1. After hypothetically-examined systemic rehabilitation education, the total of the score of family stress surveyed in 34 items of three domains was compared between the experimental group and the control group. There was no statistically significant difference between two groups; mean score of experimental group=2.28, that of control group=2.93(t=.17, df=59, p=. 66). 2. In the survey on family stress in 34 items, the items over mean score 3.0 were firstly the anxiety of possible disability and relapse of the disease and secondly to watch the patient's suffering without doing anything in the domain of the change of the disease and the difficulty in caring. And the items of the lowest stress with less than mean 2.0 score were little chance to meet the relative and friends, inconsistent treatment and attitude of the medical workers and the change of the attitude of the relative due to the patient orderly in the domain of social and personal relation and the responsibility as the family. The items which showed the difference between two groups were aggravation of neighboring patient(t=3.36, df= 59, p=.001) and the possibility of patient's death(t=2.19, df=58.38, p=.033) in the domain of the change of the disease and the difficulty in caring. 3. In the study on the stress difference according to general features of the family with the stroke patient, the score of family stress with the occupation was higher with mean 2.49 than that of the family stress without occupation with mean 2.16, but there was no significant difference. (F=5.21, df=1/59, p=.026). 4. In the study on the stress difference according to social property of the patient and the characteristic of the disease, there was significant difference in the age of the patients (F=2.98, df=3/57, p=.039). These results show that even if there is no statistically significant difference between two groups, sixteen of the experimental group are less than 3.0 in ADL score(standard 6 score)while eight of the control group are less than 3.0 and that ten of the experimental group are in the year range of 39-49 while four of the control group are in the year range of 39-49 which showed significant difference in family stress. These imply that there is a possibility that the experimental group have serious and fundamental stress resulting in high pretest stress compared with the control group. It might be due to the characteristic of simulated control group pretest-posttest design that the psychologic-supportive effect by the education was not observed. On the basis of these results, the followings are suggested. 1) A study on the nursing-mediated method to reduce the stress in the items which are not resolved by rehabilitation education, a study on nursing according to the patient's age and a study on the supportive nursing toward the family with occupation are required. 2) More than two times consecutive nursing-mediated rehabilitation education to measure the family stress is required. 3) Comprehensive and multilateral systemic education program including the instruction on western-eastern medicine, physical therapy, exercise and diet through collaboration of the experts in each field is required. 4) Family stress at home as well as in the hospital needs to be estimated and home rehabilitation and home-nursing needs to be continued.

• 센서학회지
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• 제11권1호
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• pp.9-17
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• 2002

X-선 저장 형광체 $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$의 조성 조건을 조사하고, 제조한 형광체의 광자극발광 강도, 스펙트럼, fading 특성 및 선량의존성을 조사하였다. 그리고 이 특성을 상업적으로 시판하고 있는 일본 부사(富士)사진필름회사 제품 영상판(ST-III)의 특성과 비교하였다. $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ 형광체의 최적 제조 조건은 $Eu_F3$ 0.5mol%, NaF 4.0mol% 그리고 조성비 x=0.3 이었으며, 소결온도는 수소 분위기에서 $950^{\circ}C$이었다. 조성비 x=0일 때 $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ 형광체의 스펙트럼영역은 $365{\sim}420\;nm$이었고, 최대 발광강도는 390 nm 이었다. $x{\neq}0$일 때 스펙트럼의 파장영역과 피이크 파장은 조성비 x가 증가할수록 장파장쪽으로 이동하였다. X-선 조사선량과 PSL 강도 사이에는 좋은 직선성을 나타내었다. 형광체의 fading 특성은 x=0.3일 때 가장 좋았으며, $I^-$ 이온의 농도가 증가할수록 저하되는 경향을 나타내었다. 또한 $BaFBr_{1-x}I_x:Eu^{2+}$ 격자상수는$I^-$이온의 농도가 증가할수록 커졌다.

• 자원환경지질
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• 제19권3호
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• pp.199-218
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• 1986

울산(蔚山)의 철 중석 스카른광상에서 산출되는 유비철석(硫砒鐵石)은 그의 산출상태(産出狀態) 광물공생관계(鑛物共生關係) 화학조성(化學組成)을 근거로 세 가지 유형으로 구분된다. 유비철석(硫砒鐵石) I 은 다금속광화작용(多金屬鑛化作用) 초기에 정출된 것으로 주로 스카른대 내에서 산점상으로 분포하며, Ni-Fe-Co계 유화물과 밀접한 공생관계를 보여준다. 유비철석(硫砒鐵石) I 의 화학조성은 Ni, Co의 함량이 현저하게 높고 As/S(원자비(原子比))>1으로 과잉(過剩)의 비소를 함유한다. 유비철석(硫砒鐵石) II는 Cu 또는 As 광석중에서 산출되며, 비독사석 휘창연석 비스무스 황동석 섬아연석과 밀접한 공생관계를 보여준다. 유비철석(硫砒鐵石) II의 화학조성은 Ni, Co의 함량이 극히 미량이며, As/S>1으로 과잉(過剩)의 비소를 함유한다. 유비철석(硫砒鐵石) III은 최후기 열수광맥 형성시기에 정출되었으며, 황철석 방연석 섬아연석 자류철석과 밀접한 공생관계(共生關係)를 보여준다. 유비철석(硫砒鐵石) III의 화학조성(化學組成)은 $$As/S1{\leq_-}1$$로 과잉(過剩)의 S를 함유한다. 유비철석(硫砒鐵石) I 은 Ni, Co의 함유량이 1%이상이므로 지질온도계(地質溫度計)로 사용할 수 없지만, 유비철석(硫砒鐵石) II 는 비스무스-휘창연석의 공생관계(共生關係)를 보여 주고 있으므로, 이를 Kretschmar and Scott (1976)에 의한 $1/T-f(S_2)$도에 적용시켜보면 유비철석(硫砒鐵石) II의 정출환경은 $T=460{\sim}470^{\circ}C$, log $f(S_2)=-7.4{\sim}7.0$이고, 유비철석(硫砒鐵石) III의 정출환경은 $T=320{\sim}440^{\circ}C$, log $f(S_2)=-9.0{\sim}7.0$으로 추정된다.

• 분석과학
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• 제33권1호
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• pp.33-41
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• 2020

Wet precipitation samples were collected in Jeju City and Mt. Halla-1100 site (a site at an altitude of 1100 m on Mt. Halla) during 2011-2013, and their major ionic species were analyzed to examine the chemical composition and characteristics. A comparison of ion balance, electric conductivity, and acid fraction of precipitation revealed correlation coefficients in the range of r = 0.950~0.991, thereby implying the high quality of analytical data. Volume-weighted mean pH and electric conductivity corresponded to 4.86 and 25.5 µS/cm for Jeju City, and 4.98 and 15.1 µS/cm for Mt. Halla-1100 site, respectively. Ionic strengths of the wet precipitation in Jeju City and Mt. Halla-1100 site corresponded 0.3 ± 0.5 and 0.2 ± 0.2 mM, respectively, thereby indicating that more than 30 % of total precipitation was within a pure precipitation criteria. The precipitation with a pH range of 4.5 - 5.0 corresponded to 40.8 % in Jeju City, while the precipitation with a pH range of 5.0 - 5.5 corresponded to 56.9 % in Mt. Halla-1100 site, thereby indicating slightly more weak acidity than that in Jeju city. The volume-weighted mean concentration (µeq/L) of ionic species was in the order of Na⁺ > Cl^- > nss-SO₄^2- > NO₃^- > Mg²⁺ > NH₄⁺ > H⁺ > nss-Ca²⁺ > PO₄^3- > K⁺ > CH₃COO^- > HCOO^- > NO₂^- > F^- > HCO₃^- > CH₃SO₃^- at Jeju City area, while it corresponded to Na⁺ > Cl^- > nss-SO₄^2- > NO₃^- > NH₄⁺ > H⁺ > Mg²⁺ > nss-Ca²⁺ > PO₄^3- > CH₃COO^- > K⁺ > HCOO^- > NO₂^- > F^- > HCO₃^- > CH₃SO₃^- at Mt. Halla-1100 site. The compositions of sea salts (Na⁺, Cl^-, Mg²⁺) and secondary pollutants (NH₄⁺, nss-SO₄^2-, NO₃^-) corresponded to 66.1 % and 21.8 %, respectively, in Jeju City and, 49.9 % and 31.5 %, respectively, in Mt. Halla-1100 site. The acidity contributions in Jeju City and Mt. Halla-1100 site by inorganic acids, i.e., sulfuric acid and nitric acid, corresponded to 93.9 % and 91.4 %, respectively, and the acidity contributions by organic acids corresponded to 6.1 % and 8.6 %, respectively. The neutralization factors in Jeju City and Mt. Halla1100 site by ammonia corresponded to 29.8 % and 30.1 %, respectively, whereas the neutralization factors by calcium carbonate corresponded to 20.5 % and 25.2 %, respectively. From the clustered back trajectory analysis, the concentrations of most ionic components were higher when the airflow pathways were moved from the continent to Jeju area.

• 한국방사선학회논문지
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• 제5권6호
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• pp.335-341
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• 2011

본 연구는 미나리와 울금의 방사선 피폭이 어떠한 영향이 미치는지 알아 보고자 하였다. 실험동물은 ICR계 5주령 25~30g 수컷 50 마리를 마우스를 사용하여, 5 마리를 하나의 군으로 3 Gy 대조군(A), 5 Gy대조군(B), 3 Gy 미나리 전처치(C), 5 Gy 미나리 전처치(D), 3 Gy 미나리 후처치(E), 5 Gy 미나리 후처치(F), 3 Gy 울금 전처치(G), 5 Gy 울금 전처치(H), 3 Gy 울금 후처치(I), 5 Gy 울금 후처치(J)으로 설정하였고, 대조군(A, B)은 방사선 조사 후 7 일 동안 생리식염수 500mg/kg/day)를 마우스에 경구투여 하였고, 후처치 대조군(E, F, I, J)도 방사선조사 후 7일 동안 미나리(500mg/kg/day)와 울금(500mg/kg/day)을 각각 마우스에 경구투여 하였다. 또 이와 같은 방법으로 전처치 대조군(C, D, G, H)은 미나리(500mg/kg/day)와 울금 (500mg/kg/day)을 각각 마우스에 7 일 동안 경구투여 후 방사선 조사를 하였다. 그 결과 3 Gy 대조군에서 백혈구 평균수치(마우스 5 마리)는 평균 200K/${\mu}L$, 3 Gy 미나리 전처치군에서는 평균 6,46K/${\mu}L$로 정상수치(1.8-10.7 K/${\mu}L$)로 되었다. 3 Gy 울금 전처치의 백혈구 평균수치는 23.33K/${\mu}L$로 정상수치는 아니지만, 200K/${\mu}L$에 비하여 정상수치에 가까워졌음을 알 수가 있다. 3 Gy 대조군에서 림프구의 평균 수치는 118.87K/${\mu}L$로, 3 Gy 울금 전처치군은 1.51 K/${\mu}L$로 림프구 정상수치(0.9-9.3K/${\mu}L$)로 나타내었다. 혈소판에서는 3 Gy 대조군의 평균 수치는 4000K/${\mu}L$, 3 Gy 미나리전처치군은 1107 K/${\mu}L$, 3 Gy 울금 전처치군은 2759.6 K/${\mu}L$로 혈소판정상수치(592-2972 K/${\mu}L$)로 나타내었다. 위의 결과로 미나리와 울금이 방사선 피폭에 대한 예방적 차원에서 방어효과가 있는 것으로 사료되었고, 동물실험에서는 혈구수치가 정상수치로 돌아오는 것을 알 수가 있었다. 이 실험을 바탕으로 향 후 다양한 연구가 선행되어야 할 것으로 사료되는 바이다.