• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1737-1740
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• 2006

The optimized structures and complexation energies of bis(18-crown-6-ether) analogue (2) of Trgers base (1) with a series of primary alkylbisammonium ions have been calculated by DFT B3LYP/6-31G(d,p) method. The calculated complexation efficiency (-142.84 kcal/mol) of 2 for butane-1,4-diylbisammonium guest is better than twice of the value (-61.40 kcal/mol) for butylammonium ion. The multiple hydrogen-bond abilities for the complexes are described as the function of the length of the alkyl substituents of the bisammonium guests with normal-alkyl chain [$-(CH_2)_{n-}$, n = 4-8]. The longer bisammonium guest shows the stronger hydrogen-bonding characterizations (the distance and the quasi-linear angle of the N-H…O) to the host 2 than the shorter bisammonium ions. These calculated results agree with the experimental data of the complexation of 2 with bisammonium salts ([$NH_3(CH_2)_nNH_3$] $Cl_2$).

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.696-701
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• 2005

조화가진력이 작용하는 고정경계를 가진 완전원판의 비선형 진동에 대한 응답특성을 연구하였다. 원판의 비대칭모드의 고유진동수 근처에 가진주파수가 작용하는 주공진에서의 응답은 정상파(standing wave)뿐만 아니라 진행파(traveling wave)가 존재 한다고 알려져 있다. 주공진 근처의 정상상태 응답곡선에서 최대한 5개의 안정한 응답이 존재하는 것으로 밝혀졌으며, 이들은 1개의 정상파와 4개의 진행파로 나타난다. 이 진행파 중 2개는 가진진동수가 변화함에 따라 Hope분기에 의해 안정성을 잃은 후 주기배가운동을 거쳐 흔돈운동에 이르게 된다. 초기조건에 의해 각각의 끌개(attractor)에 흡인되는 흡인영역의 경계를 주평면의 개념을 통하여 구하였으며, 가진진동수가 변화함에 따라 안정한 해가 혼돈운동에 이르는 과정에 대해 흡인영역의 경계가 변화되는 특성을 관찰하였으며, 흡인영역 경계에 대한 프랙털 차원(fractal dimension)을 계산하였다.

• 한국산학기술학회논문지
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• 제21권7호
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• pp.331-341
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• 2020

본 연구는 고혈압, 당뇨 환자를 대상으로 경험공유 자가관리 프로그램을 시행하여 대상자들의 생리적 지수, 지식, 자가관리 이행도에 미치는 효과를 파악하기 위해 시도된 비동등성 유사실험연구이다. 2018년 5월 1일부터 10월 31일까지 G시 보건진료소에 등록된 고혈압, 당뇨병 환자 실험군 30명, 대조군 25명을 대상으로 시행하였다. 실험군은 12주간의 경험공유 자가관리 프로그램에 참여하였고 대조군은 일반적인 보건진료소의 서비스를 제공하였다. 자료분석은 SPSS/WIN 22.0 프로그램을 이용하여 x² test (Fisher's exact test), Mann-Whitney test, Ranked ANCOVA로 분석하였다. 연구결과 경험공유 자가관리 프로그램 적용 후 고혈압환자의 수축기혈압(F=14.56, p<.001), 이완기혈압((F=7.05, p=.012), 지식(F=14.30, p=.001), 자가관리 이행도(F=29.73, p<.001)에서 두 군간에 유의한 차이가 있었고, 당뇨병 환자의 지식(F=7.92, p=.010), 자가관리 이행도(F=4.54, p=.044)에서 두 군간에 유의한 차이가 있었다. 따라서 지역사회 고혈압 환자의 혈압감소와 고혈압, 당뇨병 환자의 지식향상, 자가관리 이행증진을 위해 경험공유를 활용한 자가관리 프로그램은 효과적이라 생각된다.

• Korean Journal of Acupuncture
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• 제36권1호
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• pp.1-18
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• 2019

Objectives : The purpose of this study was to evaluate the effectiveness and safety of acupuncture treatment for recovery of patients with vertebral compression fracture(VCF). Methods : We searched ten English and Chinese and seven Korean database up to April 2018. Randomised controlled trials(RCTs), quasi-RCTs, non-radomised Controlled Trials(CCTs) were eligible. Quasi-RCTs and CCTs were assessed only for safety assessment. Pain and adverse events were primary outcome of this review. Quality of life, dysfunction, patient satisfaction, incidence of new vertebral compression fracture were regarded as secondary outcomes. The risk of bias was assessed by two independent authors using the Cochrane risk of bias tool. Level of evidence was tabulated using the GRADE methods. Results : Of 1656 screened, 15 RCTs, 1 quasi-RCT and 3 CCTs were included. Number of participants per study ranged from 45 to 135. Most of the studies had unclear or high risk of bias and considerable heterogeneity in terms of type of intervention, comparison and time-points for outcome measurement. Compared to usual care alone, acupuncture combined with usual care showed short-term favorable results for pain relief in patients with VCF(5 studies, n=252, MD -1.05 point on a 0 to 10 point scale, 95% CI -1.45 to -0.65, $I^2=74%$). Four studies reported mild and temporary adverse events, and no serious adverse events were reported. One study descriptively reported that acupuncture was effective for improving quality of life without providing numerical outcomes. There were no reports of patient satisfaction and incidence of new VCF. Conclusions : Level of evidence is very low for the effectiveness and safety of acupuncture for pain, harms and other clinical outcomes in patients with VCF. Included studies suffered from incomplete reporting, high or unclear risk of bias and substantial heterogeneity between studies. Future high-quality RCTs are needed to assess whether acupuncture is beneficial for recovery of patients with VCF.

• 한국광학회지
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• 제28권6호
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• pp.290-294
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• 2017

카세그레인 망원경은 오목한 주경과 볼록한 부경으로 이루어져있다. 특히 부경의 경우 크기는 작지만 볼록한 형태로 빛을 모두 퍼트려 파면오차 측정이 어렵다. 본 논문에서는 비구면 계수가 여러 개인 볼록비구면 반사경의 파면오차를 Simpson-Oland-Meckel (SOM) 힌들 테스트를 적용하여 측정하였다. 그리고 실험 구성에서 발생하는 계통오차를 분리해내기 위해 QN 절대측정법을 추가로 적용함으로써 힌들 렌즈 제작 및 정렬 오차를 포함한 계통오차를 보정하고 볼록비구면 반사경만의 파면오차를 구하였다. 이렇게 구한 볼록비구면 반사경의 파면오차와 QED사의 ASI (Aspheric Stitching Interferometer)로 측정한 파면오차와 비교한 결과, 모두 $45^{\circ}$ 방향의 비점수차 형태를 가지며 rms 값의 차이가 약 2.5 nm rms 이내로 매우 작음을 확인하였다.

• 한국농촌간호학회지
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• 제3권1호
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• pp.15-23
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• 2008

Purpose: This study was done to examine the effects of a Program Promoting Efficacy Expectation, as to whether the program improved self-efficacy, health promotion behavior and quality of life for rural middle-aged women. The program was based on Bandura's self-efficacy theory and Pender's health promoting behavior theory. Method: The research design was a quasi experimental, nonequivalent control group pretest-posttest design. Data were collected from August 25 to December 7, 2000. The participants were 40 to 59 year old women who resided on Je-ju island. Among the 83 participants, 43 were assigned to experimental group and the rest to the control group. Results: The level of self efficacy and the degree of health promoting behavior of participants in the experimental group was higher than those in the control group (t=12.82, p=0.0001; t=14.13, p=0.0001). Also, the level of quality of life in the experimental group was higher than that of the control group (t=12.02, p=0.0001). Conclusion: The Efficacy Expectation Promotion Program was an effective nursing intervention for improving self-efficacy, health promotion behavior and quality of life. Therefore, when nurses are planning programs directed at improving health promotion behavior in rural middle aged women, they should consider the concept of self-efficacy.

• 한국보건간호학회지
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• 제15권1호
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• pp.96-110
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• 2001

The purpose of this study was to examine the effect of emotional and informational support intervention on role stress and depression of primary family caregivers caring stroke patients and to develop an effective nursing intervention method for them. This study selected the quasi-experiment, based on pre-test and post-test design of non-equivalent control group as a method of study. This study was conducted with 69 primary family caregivers caring stroke patients hospitalized in K and D hospitals in Daegu from August 20 to October 25, 2000. Out of them, 34 were placed in the experimental group, and 35 in the control group. The emotional and informational intervention program was divided into two aspects-emotional support and informational support- and executed three times, using prepared instruments and a guidebook. The intervention program consisted of the 1st intervention for one or one-half hour, the 2nd intervention for 30 minutes in two or three days after the 1st intervention. and the 3rd intervention for 30minutes in another two or three days after the 2nd intervention. Pre-test was carried out just before the 1st intervention, and the post-test was carried out right after the 3rd intervention, in order to collect data. The measuring instrument of role stress used was one that was modified to the role stress instrument of Yang Young-hee(1992) and the stress instrument of Choi Eun-sook (1992). The reliability was Cronbach's $\alpha=.8271$. The measuring instrument of depression used was one that was developed by Beck(1967) and standardized by Han Heung-moo et al(1986). The reliability was Cronbach's $\alpha=.8693$. Data were analyzed with percentage, mean, standard deviation, $x^2-test$, t-test and Paired t-test by using SPSS 9.0 program. The results of this study are summarized as follows: 1. Role stress score of the experimental group was revealed to be significantly lower than that of the control group 2. Depression score of the experimental group was revealed to be significantly lower than that of the control group Accordingly, the emotional and informational support intervention can be a way to reduce role stress and depression of primary family caregivers caring stroke patients.

• Wind and Structures
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• 제13권1호
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• pp.37-55
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• 2010

In this paper South Africa is divided into strong wind climate zones, which indicate the main sources of annual maximum wind gusts. By the analysis of wind gust data of 94 weather stations, which had continuous climate time series of 10 years or longer, six sources, or strong-wind producing mechanisms, could be identified and zoned accordingly. The two primary causes of strong wind gusts are thunderstorm activity and extratropical low pressure systems, which are associated with the passage of cold fronts over the southern African subcontinent. Over the eastern and central interior of South Africa annual maximum wind gusts are usually caused by thunderstorm gust fronts during summer, while in the western and southern interior extratropical cyclones play the most dominant role. Along the coast and adjacent interior annual extreme gusts are usually caused by extratropical cyclones. Four secondary sources of strong winds are the ridging of the quasi-stationary Atlantic and Indian Ocean high pressure systems over the subcontinent, surface troughs to the west in the interior with strong ridging from the east, convergence from the interior towards isolated low pressure systems or deep coastal low pressure systems, and deep surface troughs on the West Coast.

• 대한기계학회논문집B
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• 제21권7호
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• pp.919-927
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• 1997

The main purpose of this study is to determine bifurcation as the primary instability of a glass melting furnace. Steady-state and unsteady characteristics of natural convection in the partially open cavity as appeared in a glass melting furnace is investigated by using numerical analysis. Three types of convection, such as steady laminar, unsteady periodic or unsteady quasi-periodic convection may occur according to the temperature difference between upper two isothermal surfaces along the depth of cavity in a glass melting furnace. In the temperature difference of 150-900 K between batch and free surface, the larger the temperature difference, the weaker the convection strength and unsteadiness. Since the glass viscosity is increasing exponentially in the lower temperature, the batch freezes the thermofluidic field especially below the surface of it. If the depth of cavity is 0.5 m, the bifurcation to time-dependent natural convection may occur in the range of 60-650 K. If that is 1.0 m, it may occur in the whole range of temperature difference.

• 조명전기설비학회논문지
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• 제22권7호
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• pp.7-15
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• 2008

A single active capacitor snubber-assisted soft-switching sinewave pulse modulation utility-interactive power conditioner with a three-winding flyback high frequency transformer link and a bidirectional active power switch in its secondary side has been proposed. With the aid of the switched-capacitor quasi-resonant snubber cell, the high frequency switching devices in the primary side of the proposed DC-to-AC sinewave power inverter can be turned-off with ZVS commutation. In addition to this, the proposed power conditioner in the DCM can effectively take the advantages of ZCS turn-on commutation. Its output port is connected directly to the utility AC power source grid. At the end, the prototype of the proposed HF-UPC is built and tested in experiment. Its power conversion conditioning and processing circuit with a high frequency flyback transformer link is verified and the output sinewave current is qualified in accordance with the power quality guidelines of the utility AC interactive power systems.