• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.934-940
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• 2010

The reduction of [$Os_3(CO)_{11}P(OMe)_3$] and subsequent ionic coupling of the reduced species with $[Ru({\eta}^5-C_5H_5)(CH_3CN)_3]^+$ resulted in the formation of [$Os_3(CO)_{11}P(OMe)_3(Ru({\eta}^5-C_5H_5))_2$] which can be converted to spiked tetrahedral cluster, [$HOs_3(CO)_{11}P(OMe)_3Ru_2({\eta}^5-C_5H_5)(C_5H_4)$] via the intramolecular hydrogen transfer. Due to the unavailability of a suitable single crystal, the PW91/SDD and LDA/SDD density functional methods were used to predict possible structures and the available spectroscopic information (IR, NMR) of [$Os_3(CO)_{11}P(OMe)_3(Ru({\eta}^5-C_5H_5))_2$]. The most probable geometry found by constrained search is the isomer (a2) in which the phosphite, $P(OMe)_3$, occupies an axial position on one of the two osmium atoms that is edge bridged by the $Ru(CO)_2({\eta}^5-C_5H_5)$ unit. By using the most probably geometry, the predicted infrared frequencies and $^1H$, $^{13}C$ and $^{31}P$ NMR chemical shifts of the compound are in the same range as the experimental values. For this type of complex, the LDA/SDD method is appropriate for IR predictions whereas the OPBE/IGLO-II method is appropriate for NMR predictions. The activation energy and reaction energy of the intramolecular hydrogen transfer coupled with the structural change of the transition metal framework were estimated at the PW91/SDD level to be 110.32 and -0.14 kcal/mol respectively.

• 대한토목학회논문집
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• 제30권4C호
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• pp.175-183
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• 2010

대구경 말뚝의 수평 하중전이 거동 및 변형 해석을 위해 수평하중전이 해석법(p-y 곡선법)이 널리 사용되고 있다. 본 연구에서는, 기존 p-y 해석법의 단점을 보완하기 위하여, 지반의 연속성을 고려한 수평 지반저항력 산정법을 고찰하였으며, 3차원 유한요소 해석을 이용하여 수평하중을 받는 말뚝의 연속체 모델링을 수행하였다. 이를 바탕으로 심도별 말뚝 주변부 발생응력을 바탕으로 하중전이 함수를 산정하고 지반 연속성에 영향을 주는 인자들을 매개변수 연구를 통해 검증하였다. 현장재하시험 사례와의 비교분석 결과, 말뚝 주변부 지반응력을 이용한 유한요소 해석방법은 기존 p-y 곡선에 비해 수평하중을 받는 말뚝의 하중전이 거동을 보다 정확히 예측할 수 있음을 확인하였다. 따라서, 수평하중을 받는 대구경, 대심도 말뚝 설계 시, 신뢰성 있는 수평하중전이 함수의 산정이 중요하며, 지반연속성을 고려하면 보다 경제적인 설계를 할 수 있음을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1185-1189
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• 2005

Two new copper vanadium borophosphate compounds, $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O,\;Cu-VBPO1\;and\;(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, Cu-VBPO2 have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, thermogravimetric analysis, IR spectroscopy, and elemental analysis. The structure of Cu-VBPO1 contains a layer anion, {$[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6$}$^{12-}$, whereas Cu-VBPO2 has an open framework anion, {$[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6$}$^{8-}$. Crystal Data: $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group I2/m (no. 12), $\alpha$ = 15.809(1) $\AA$, b = 31.107(2) $\AA$, c = 12.9343(8) $\AA$, $\beta$ = 104.325(1)$^{\circ}$, Z = 2; $(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, tetragonal, space group $P4_2$/mnm (no.136), $\alpha$ = 26.832(1) $\AA$, c = 18.021(1) $\AA$, Z = 4.

• 대한통합의학회지
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• 제9권4호
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• pp.261-270
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• 2021

Purpose : The purpose of this study is to investigate the effects of sleep duration on stress and depression in college students. The results obtained will be used as a foundational framework for fostering a healthy sleep culture among college students and for formulating measures to improve the quality of their sleep. Ultimately, we intend to produce a publicity and educational material. Methods : For this study, a survey involving 100 college students was conducted, after which data based on a final total of 95 respondents were analyzed. The information on stress and depression were first analyzed in terms of general characteristics and then organized based on the data collected to investigate the effects of sleep duration on stress and depression. The participants were divided into the following groups: "less than 6 hours," "6 to 7 hours," and "7 to 8 hours." BEPSI-K (Brief encounter psychosocial instrument-Korean) was used for stress evaluation, while K-CESD-R (Korean version of center for epidemiologic studies depression scale-revised) was utilized for depression evaluation. Results : First, according to sleep duration, the BEPSI-K scores showed a statistically significant difference in each group (p<.01). In the post-hoc test, there was a difference among the "less than 6 hours" group, the "7 to 8 hours" group. A statistically significant difference was noted (p<.01). In addition, sleep duration had a statistically significant effect on the negative (-) direction of the BEPSI-K (p<.01). Second, the K-CESD-R score according to sleep duration showed a statistically significant difference in each group (p<.01). Notably, in the post-hoc test, the "less than 6 hours" group differed from the "6 to 7 hours" group, "7 to 8 hours" group. A statistically significant difference was noted (p<.01). In addition, sleep duration had a statistically significant effect on the negative (-) direction of the K-CESD-R (p<.01). Third, for the correlation between sleep duration and stress and depression, a negative (-) correlation was found between sleep duration and BEPSI-K and K-CESD-R. Meanwhile, a positive (+) correlation was found between BEPSI-K and K-CESD-R. Conclusion : Based on the findings of this study, the sleep duration of college students has an effect on stress and depression. The results of this study can be used as a foundational framework in formulating a plan for improving the quality of sleep of college students.

• Bulletin of the Korean Chemical Society
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• 제20권6호
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• pp.715-719
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• 1999

The incorporation of cobalt into mesoporous molecular sieves MCM-41 and MCM-48 was carried out. Co-PO/MCM41 and Co-PO/MCM48 were prepared using Co(II) acetate solution adjusted to pH = 3.0 with phosphoric acid by the incipient wetness method. Photoacoustic spectroscopy (PAS) was used to study the local environments of Co(II) incorporated into mesopores. The band around 500 nm in PAS of as-prepared Co-PO/MCM41 and Co-PO/MCM48 with Co(II) acetate solution was changed to triplet bands around 600 nm. This could be assigned to the 4 A2(F)-> 4T1(P) transition of Co(II) surrounded tetrahedrally by oxygen ions after calcination. It may be attributable to that the octahedral cobalt species containing phosphate ligands in coordination sphere reacting with framework's silanol groups to be dispersed atomically onto the surface of mesoporous molecular sieves as a tetrahedral species. This is unlike that the Co in Co-Cl/MCM41 and direct-synthesized Co-MCM41 transforms to Co oxide phase upon calcination. Co-PO/MCM41 and Co-PO/MCM48 were stable while treated with water.

• Korean Journal of Radiology
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• 제20권5호
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• pp.749-758
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• 2019

Objective: To investigate whether a computer-aided diagnosis (CAD) system based on a deep learning framework (deep learning-based CAD) improves the diagnostic performance of radiologists in differentiating between malignant and benign masses on breast ultrasound (US). Materials and Methods: B-mode US images were prospectively obtained for 253 breast masses (173 benign, 80 malignant) in 226 consecutive patients. Breast mass US findings were retrospectively analyzed by deep learning-based CAD and four radiologists. In predicting malignancy, the CAD results were dichotomized (possibly benign vs. possibly malignant). The radiologists independently assessed Breast Imaging Reporting and Data System final assessments for two datasets (US images alone or with CAD). For each dataset, the radiologists' final assessments were classified as positive (category 4a or higher) and negative (category 3 or lower). The diagnostic performances of the radiologists for the two datasets (US alone vs. US with CAD) were compared Results: When the CAD results were added to the US images, the radiologists showed significant improvement in specificity (range of all radiologists for US alone vs. US with CAD: 72.8-92.5% vs. 82.1-93.1%; p < 0.001), accuracy (77.9-88.9% vs. 86.2-90.9%; p = 0.038), and positive predictive value (PPV) (60.2-83.3% vs. 70.4-85.2%; p = 0.001). However, there were no significant changes in sensitivity (81.3-88.8% vs. 86.3-95.0%; p = 0.120) and negative predictive value (91.4-93.5% vs. 92.9-97.3%; p = 0.259). Conclusion: Deep learning-based CAD could improve radiologists' diagnostic performance by increasing their specificity, accuracy, and PPV in differentiating between malignant and benign masses on breast US.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.805-810
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• 2008

Using metallic Ti powder as raw materials and 1,2-diaminocyclohexane (DACH) as the trial template, two novel reduced titanophosphate open-structures were hydrothermally isolated by varying the $H_3PO_4/H_2O$ ratio to adjust the pH value. TiPO-1 crystallizes in orthorhombic Pbca space group with cell parameters a = 21.956(3) $\AA$, b = 8.6268(11) $\AA$, c = 7.2883(9) $\AA$, V = 1380.5(3) $\AA^3$, Z = 4. TiPO-2 crystallizes in triclinic space group P$\bar{1}$ with parameters a = 5.1620(10) $\AA$, b = 8.815(2) $\AA$, c = 10.655(3) $\AA$, $\alpha$ = $99.45^{\circ}$, $\beta$ = $102.94^{\circ}$, $\gamma$ = $91.06^{\circ}$, V = 465.34 $\AA^3$. TiPO-1 is constructed by infinite -Ti-O-Ti-O- linkage that is capped by $PO_4$ groups to form a chain structure with protonated DACH molecules occupying the interchain spaces. TiPO-2 represents a rare 3-D reduced titanophosphate with 12-MR channels. The structure of TiPO-2 is a neutral framework with water molecules located in the channels.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1586-1589
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• 2005

GUMF (Global User Management Framework) that is proposed in this research can be applied to next generation network such as BcN (Broadband convergence Network), it is QoS guaranteed security framework for user that can solve present Internet's security vulnerability. GUMF offers anonymity for user of service and use the user's real-name or ID for management of service and it is technology that can realize secure QoS. GUMF needs management framework, UMS (User Management System), VNC (Virtual Network Controller) etc. UMS consists of root UMS in country dimension and Local UMS in each site dimension. VNC is network security equipment including VPN, QoS and security functions etc., and it achieves the QoSS (Quality of Security Service) and CLS(Communication Level Switching) functions. GUMF can offer safety in bandwidth consumption attacks such as worm propagation and DoS/DDoS, IP spoofing attack, and current most attack such as abusing of private information because it can offer the different QoS guaranteed network according to user's grades. User's grades are divided by 4 levels from Level 0 to Level 3, and user's security service level is decided according to level of the private information. Level 3 users that offer bio-information can receive secure network service that privacy is guaranteed. Therefore, GUMF that is proposed in this research can offer profit model to ISP and NSP, and can be utilized by strategy for secure u-Korea realization.

• 한국보건간호학회지
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• 제12권2호
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• pp.89-106
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• 1998

The Health Promotion Model by Pender(l987) was used as the conceptual framework for analyzing the health promotion behaviors. The purposes of this study were to describe health promoting life style behaviors in 245 women between the ages of 35 and 59 living in Seoul and other cities and to find their predictive factors. Data were collected from 1st to 23th. June. 1998. The tool used for this study was structured questionnaire with consisted of 8 items on general characteristics. 5 items on health related characteristics. 43 items on health promoting life style. 28 items on menopausal symptoms. 5 items on family support. and 28 items on self-efficacy. The collected data were analyzed using the SAS. yielding descriptive statistics. ANOVA. Pearson's Correlation. stepwise multiple regression. The findings of this study are as follows. 1) The mean score of health promotion behavior(3.25) is not high. The mean scores of this self actualization (3.73). interpersonal support (3.68). and nutrition (3.57). regulation of stress (3.22) in domains are higher than health responsibility (2.90). exercise (2.63). 2) The results of the comparison between the health promotion behaviors and general variables showed a statistically significant difference in education (P=.0061), domestic economy status(P=.0001). perception of health status(P=.0001) but. age. state of menstruation. perception of weight is not significant difference. 3) The correlation between health promoting life style and self-efficacy(P=.0001). family support(P=.0001) is significant. But. there is no correlation between health promoting life style and age. number of family. perception of weight. 4) In the cognitive-perceptual factors. self-efficacy (P=.0001) is very significant predictor (accounted for $39.7\%$) and in the modifying factors. family support(P=.0001) is very significant (accounted for $9.0\%$). It is same to other research results.

• 간호행정학회지
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• 제9권1호
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• pp.89-101
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• 2003

Purpose : this study was to examine the effect of using a nursing standards for the quality of nursing care in musculo-skeletal patients. Method : The approach to nursing quality assurance evaluation was selected process-outcome framework. The subjects ware 100 case of musculo-skeletal patients in orthopedic surgery nursing care unit of E. university hospital in seoul. The data of a control group were collected from 23 December 2001 to 20 March 2002 and an experimental group were collected from 1 June to 25 August 2002. The instruments used for this study were a nursing care standards in musculo-skeletal disorder patients developed by the investigator and an evaluation tool for the quality of nursing care in orthopedic surgery patients developed by soon-ook Choi in 1995. It's reliability is Cronbach alpha=.8628. The data were analyzed by means of $x^1$-test, t-test, ANOVA with SPSS program. Results : This study are as fellows : 1. Scores of the quality of nursing care in standard 1 in the experimental group were higher than those of the control group with no significant difference(t=-8.793, p=.000), scores of the quality of nursing care in standard 2 in the experimental group were higher than those of the control group with significant difference(t=-8.793, p=.000) and standard 3 in the experimental group were higher than those of the control group with significant difference(t=-10.550, p=.000). scores of the quality of nursing care in standard 4 in the experimental group were higher than those of the control group with significant difference(t=-8.793, p=.000). scores of the quality of nursing care in standard 4 in the experimental group were higher than those of the control group with no significant difference(t=-1.833, p=.070). 2. Scores of the quality of nursing care in criteria 28 of 33 criteria in the experimental group were higher than those of the control group with significant difference in 12 criteria(p<.05 ). 3. Scores of the quality of nursing care in standard 1 to standard 4(process evaluation); the experimental group were higher than those of the control group with significant difference(t=-10.704, p=.000). scores of the quality of nursing care in standard 5(outcome evaluation); the experimental group were higher than those of the control group. but no significant difference(t=-1.833, p=.070). 4. Scores of the quality of nursing care in experimental group were higher than those of the control group with significant difference(t=-10.794, p=.000). Conclusion : Through this study, I'm sure that using a nursing care standards in musculo-skeletal disorder patients improve quality of nursing care and nursing care standards are effective nursing care.