• 가족자원경영과 정책
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• 제18권1호
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• pp.47-68
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• 2014

This study investigated the relationship between smartphone addiction propensities and leisure satisfaction according to leisure time constraints among university students and attempted to promote an effective and desirable leisure culture. The main findings were as follows: First, leisure time constraints showed differences in terms of the withdrawal factors, overall smartphone addiction propensities, and leisure satisfaction; self-efficacy showed significant differences in terms of withdrawal and overall smartphone addiction propensities; and control showed a significant difference in leisure satisfaction. Second, in the case of university students, it was revealed that regardless of leisure constraints, as disturbance of daily living and tolerance are higher, leisure satisfaction is lower in those with smartphone addiction propensities.

• 디지털융복합연구
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• 제12권8호
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• pp.459-465
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• 2014

청소년의 스마트폰 중독률이 증가하고 있고 이로 인한 많은 문제점이 발생하고 있음에도 불구하고 스마트폰 중독에 관한 연구는 아직 시작단계에 있어 스마트폰 중독예방을 위한 대책마련이 시급한 실정이다. 따라서 본 연구에서는 스마트폰 이용자의 이용 동기와 자기통제력, 사회적 위축이 스마트폰 중독에 어떠한 영향을 미치는지를 확인하고자 하였다. 연구결과 첫째, 스마트폰 이용 동기 중 정보획득, 사회적 관계, 오락성, 여가시간활용 동기는 스마트폰 중독에 영향을 미치는 것으로 확인되었다. 둘째, 자기통제 특성은 조절성이 떨어질수록, 또한 충동성이 강할수록 스마트폰 중독가능성이 높은 것으로 확인되었다. 셋째, 이용자들의 사회적 위축은 스마트폰 중독에 영향을 미치는 것으로 확인되었다. 이러한 결과는 스마트폰 중독에 대한 예방 및 개선프로그램 개발에 기초자료를 제공할 것이라 사료되며, 청소년들의 스마트폰 사용의 강압적인 제지보다는 청소년들의 놀이 활동을 우선 점검하고, 스스로 조절하고 충동성을 완화시킬 수 있는 자기통제력 프로그램의 개발과 실시가 요구된다.

• 한국잠사곤충학회지
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• 제53권2호
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• pp.78-81
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• 2015

본 연구는 사육용 쌍별귀뚜라미의 배변제거를 위한 절식시간을 알아보는 것을 실험 목적으로 하였다. 귀뚜라미는 현재 드디어 한시적 식품인정을 받았다. 따라서 식용 곤충으로서 국내시판을 위한 연구의 일환으로 귀뚜라미 생체 안의 배변을 제거하여 미생물의 번식을 예방하고 이취 제거와 맛을 향상시키기 위하여 본 쌍별귀뚜라미의 절식 실험을 실시한 결과 농가와 실험실에서 두 곳 모두 절식 2일째부터는 귀뚜라미의 습성에 의해 동족포식의 카니발리즘이 발동하여 귀뚜라미의 생체가 훼손되어 나감을 관찰 하였다. 쌍별 귀뚜라미 장내 분변을 현미경으로 살펴본 결과 1일째 이후 분변은 거의 없어지고 싸움으로 획득한 귀뚜라미의 팔다리 일부가 장내에 들어 있는 양상을 보여 1일이 귀뚜라미 장내 변이 거의 없어지는 시간임을 알 수 있어 생체 운송 배달시 1일이 걸리는 기간을 감안하면 절식시간은 1일이 적당하다고 사려 되어진다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.455-458
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• 2004

This study uses time series analyses to evaluate fluctuation of water levels in a geothermal water well due to pumping, in relation to rainfall at Dongrae hot-spring site on the southeastern coast of tile Korean peninsula. The volume of water pumped from the public study wells ranges from 542 to 993 m$^3$/month, and the minimum water level ranged from 35 to 144.7 m during the measured period. Autocorrelation analysis was conducted for the withdrawal rate at the public wells, water levels and rainfall. The autocorrelation of the withdrawal rate shows distinct periodicity with 3 months of lag time, the autocorrelation of rainfall shows weak linearity and short memory with 1 months of lag time, and the autocorrelation of water levels shows weak linearity and short memory with 2 months of lag time. The cross-correlation between the pumping volume and the minimum water level shows a maximum value 1 at a delayed time of 34 months. The cross-correlation between rainfall and the minimum water level shows a maximum value of 0.39 at a delayed time of 32 months.

• Tuberculosis and Respiratory Diseases
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• 제79권1호
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• pp.22-30
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• 2016

Background: The purpose of this study was to document outcomes following withdrawal of a single inhaler (step-down) in chronic obstructive pulmonary disease (COPD) patients on triple therapy (long-acting muscarinic antagonist and a combination of long-acting ${\beta}2$-agonists and inhaled corticosteroid), which a common treatment strategy in clinical practice. Methods: Through a retrospective observational study, COPD patients receiving triple therapy over 2 years (triple group; n=109) were compared with those who had undergone triple therapy for at least 1 year and subsequently, over 9 months, initiated inhaler withdrawal (step-down group, n=39). The index time was defined as the time of withdrawal in the step-down group and as 1 year after the start of triple therapy in the triple group. Results: Lung function at the index time was superior and the previous exacerbation frequency was lower in the step-down group than in the triple group. Step-down resulted in aggravating disease symptoms, a reduced overall quality of life, decreasing exercise performance, and accelerated forced expiratory volume in 1 second ($FEV_1$) decline ($54.7{\pm}15.7mL/yr$ vs. $10.7{\pm}7.1mL/yr$, p=0.007), but there was no observed increase in the frequency of exacerbations. Conclusion: Withdrawal of a single inhaler during triple therapy in COPD patients should be conducted with caution as it may impair the exercise capacity and quality of life while accelerating $FEV_1$ decline.

• 한국동물위생학회지
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• 제23권2호
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• pp.143-152
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• 2000

Sulfamethazine sodium was orally administrated to sprague-dawley strain male rats(body weight, 200-300g) with using sonde at the rate of 20 mg/100g body weight(recommended therapeutic dose) on once a day for 3 days. There were investigated the depletion rate of the sulfamethazine in serum, liver and skeletal muscle of rat at the time 8 hours, 1st, 2nd, 3rd, 4th, 5th and 6th day after administration sulfamethazine sodium. 1. The mean concentrations of sulfamethazine in serum according to the time lapsed after oral administration of the sulfamethazine soudijm were showed 215.53$\pm$42.99 ppm at the 8 hours after withdrawal of medicated sulfamethazine. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in serum were significantly (p<.05) decreased 25.87$\pm$5.18 ppm at 1st day, 2.30$\pm$0.61 ppm at 3rd day and 0.11$\pm$0.02 ppm at 6th day after withdrawal of medicated sulfamethazine. 2. The mean concentrations of sulfamethazine in liver were significantly (p<.05) decreased 81.77 $\pm$ 12.88 ppm to 0.11$\pm$0.03 ppm between 8 hours and 6th day according to the time lapsed after oral administration of the sulfamethazine sodium for 3 days. 3. After oral administration of the sulfamethazine sodium, the mean concentrations of sulfamethazine in skeletal muscle were significantly (p<.05) decreased 35.96$\pm$1.39 ppm to 0.009$\pm$0.001 ppm between 8 hours and 6th day after withdrawal of medicated sulfamethazine. At the 4th day, the concentrations of sulfamethazine residues were showed 0.10 $\pm$ 0.04 ppm below 0.1 ppm at the permitted limit concentration of muscle in Korea. 4. After oral administration of the sulfamethazine sodium once a day for 3 days, there were showed the highest concentration in serum (215.53$\pm$42.99 ppm) than in liver(81.77$\pm$12.88 ppm) and skeletal muscle (35.96$\pm$1.39 ppm) at the 8 hours after withdrawal of medicated sulfamethazine. The mean concentration of sulfamethazine residues in serum, liver and skeletal muscle were gradually decreased according to the time lapsed.

• The Korean Journal of Pain
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• 제18권1호
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• pp.10-14
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• 2005

Background: Previous studies have suggested synergistic analgesic drug interactions between NSAIDs and opioids in neuropathic and inflammatory pain models. The aim of this study was to investigate the analgesic drug interaction between intraperitoneal (IP) ketorolac and morphine in radiant thermal stimulation rat. Methods: Initially, we assessed the withdrawal latency time of the hindpaw to radiant thermal stimulation every 15 min for 1 hour and every 30 min for next 1 hour after IP normal saline 5 ml (control group). The latency time was changed into percent maximal possible effect (%MPE). Next, IP dose response curves were established for the %MPE of morphine (0.3, 1, 3, 10 mg/kg) and ketorolac (3, 10, 30 mg/kg) to obtain the $ED_{50}$ for each agent. And we confirmed that the IP morphine effect was induced by opioid receptor through IP morphine followed by IP naloxone. At last, we injected three doses of IP ketorolac (3, 10, 30 mg/kg) mixed with one dose of morphine (2 mg/kg) for fixed dose analysis. Results: IP morphine delayed the paw withdrawal latency time dose dependently, but not ketorolac. $ED_{50}$ of IP morphine was 2.1 mg/kg. And the IP morphine effect was reversed to control level by IP naloxone. IP ketorolac + morphine combination showed no further additional effects on paw withdrawal latency time over morphine only group. Conclusions: IP ketorolac did not produce antinociceptive effect during radiant thermal stimulation. There was neither additional nor synergistic analgesic interaction between IP morphine and ketorolac in thermal stimulation rat.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.106-111
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• 2007

The current study was conducted to determine the optimum length of feed withdrawal for pre-harvest broilers. A total of three hundred broilers were sampled from an industrial population, and 30 chicks for each weight group (e.g., 1.5 and 2.5 kg) were randomly assigned to feed withdrawal treatments for 0, 3, 6, 9 and 12 h. Weight loss, yield, muscle pH, objective meat color and weights of gastro intestinal contents, crop, gizzard, provenriculus, small intestine, caecum, and rectum were determined. Live weight loss was significantly (p<0.05) increased as length of feed withdrawal extended. A significant (p<0.05) carcass yield for both 1.5 and 2.5 kg groups coincided after 9 and 6 h feed withdrawal, respectively. Net weights of intestinal contents for crop and gizzard were significantly (p<0.05) reduced by 6 h, and the reduction for proventriculus and small intestine occurred from 3 h. A noticeable effect of feed withdrawal on pH for breast muscle at 3 h postmortem occurred only when chicks were fasted for 3 h of which pH (6.05) was significantly (p<0.05) higher than that for other groups including the control (5.74). There was a linear tendency of higher lightness (Hunter L* value) numerically for chicks fasted for longer periods. The highest coefficient of determinations of regression models to estimate weight loss as a function of fasting period and body weights were achieved, when the models included both linear and quadratic terms for fasting period, and linear term for both 1.5 ($R^2=0.76$) and 2.5 kg ($R^2=0.78$) body weight groups. Given the practical aspect, approximately 1.5 kg of body weight is dominant, weight loss could be predicted by the following function; live weight $loss=26.6-0.28{\times}(fasting period)^2+12.34{\times}pasting\;period-0.012{\times}body\;weight$, $R^2=0.76$. Current data implied that the optimum fasting time for pre-slaughter chicks varied depending on slaughter weight; 6 and 9-h fasting were recommendable for 2.5 and 1.5 kg chicks, with little effect on objective meat color.

• 대한토목학회논문집
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• 제32권2B호
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• pp.113-121
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• 2012

유역에서 집중호우가 발생하였을 경우 저수지 내로 고탁수층이 유입된다. 본 연구에서는 성층저수지로 유입된 고탁수층에 대한 선택취수 탁수배제 능력을 검토하기 위하여 3차원적인 접근흐름에 대한 현장실험 및 수치해석 연구를 수행하였다. 다항목수질모니터링시스템(YSI6600EDS)과 초음파유속계(YSI6600ADV)을 이용하여 선택취수시의 온도, 탁도 및 유속분포를 측정하였다. 3차원 모형인 FLOW-3D를 이용하여 저수지 내 취수탑 주변에서 유동형태를 예측하였으며, 현장실험에서의 유속 측정값과 비교분석한 결과 연직유속분포를 잘 모의함을 확인할 수 있었다. 또한 관측 자료들을 분석한 결과에 의하면 표면 취수에 비해 저층 선택취수를 수행하는 것이 고탁수층에 대한 저수지내 탁도 배제능력이 46% 증가하는 것으로 나타났다. 3차원 수치모의 해석결과, 표면취수에 비하여 중층취수를 하는 경우에는 저수지내 탁도 배제능력이 10% 증가하였고, 저층취수를 하는 경우에는 30% 증가하였다. 따라서 저수지 내 고탁수를 배제하기 위해서는 중층 또는 저층의 선택취수를 수행하는 것이 탁수배제 능력 면에서 우수한 것으로 분석되었다. 또한 수치효율이 매우 높은 1차원 SELECT 모형에서도 유사한 결과를 보여 주었다.

• 대한수의학회지
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• 제63권3호
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• pp.23.1-23.9
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• 2023

This study was conducted to investigate tiamulin (TML) residues in the edible tissues of orally dosed broiler chickens and to re-establish the withdrawal time (WT). Thirty-six healthy Ross broiler chickens were administered 0.5 (TML-1) and 2.5 kg (TML-2) per ton feed, respectively, of the drug containing TML 78 g/kg for 10 days. Twenty-four tissue samples were collected from 6 chickens in each of the TML-1 and TML-2 groups on 0, 1, 3, and 5 days after drug administration, respectively. The residual concentrations of TML were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The correlation coefficient of the calibration curves was 0.9978 to 0.9998, and the limits of detection and the limits of quantification (LOQ) were in the range of 0.03 to 0.06, and 0.1 to 0.2 ㎍/kg, respectively. Recoveries ranged between 89.0% to 116.7%, and the coefficients of variation were less than 13.9%. After the drug administration, TML in the TML-1 and TML-2 groups was detected above the LOQ in 1 and 6 samples of liver, respectively, at day 0, and in 1 liver sample from both groups on day one. At 3 days after administration, TML was detected below the LOQ in all samples of TML-1 and TML-2. The calculated WT of TML in both TML-1 and TML-2 using the WT calculation program WT 1.4 was 0 days. In conclusion, the developed analytical method is suitable for detection, and the calculated WT of TML in poultry edible tissues is shorter than the current recommended WT of 7 days for TML in broiler chickens.