• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.2010-2018
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• 2017

Mixotrophic microalgal growth gives a great premise for wastewater treatment based on photoautotrophic nutrient utilization and heterotrophic organic removal while producing renewable biomass. There remains a need for a control strategy to enrich them in a photobioreactor. This study performed a series of batch experiments using a mixotroph, Chlorella sorokiniana, to characterize optimal guidelines of mixotrophic growth based on a statistical design of the experiment. Using a central composite design, this study evaluated how temperature and light irradiance are associated with $CO_2$ capture and organic carbon respiration through biomass production and ammonia removal kinetics. By conducting regressions on the experimental data, response surfaces were created to suggest proper ranges of temperature and light irradiance that mixotrophs can beneficially use as two types of energy sources. The results identified that efficient mixotrophic metabolism of Chlorella sorokiniana for organics and inorganics occurs at the temperature of $30-40^{\circ}C$ and diurnal light condition of $150-200{\mu}mol\;E{\cdot}m^{-2}{\cdot}s^{-1}$. The optimal specific growth rate and ammonia removal rate were recorded as 0.51/d and 0.56/h on average, respectively, and the confirmation test verified that the organic removal rate was $105mg\;COD{\cdot}l^{-1}{\cdot}d^{-1}$. These results support the development of a viable option for sustainable treatment and effluent quality management of problematic livestock wastewater.

• Journal of Korean Society for Atmospheric Environment
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• 제18권E4호
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• pp.203-213
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• 2002

Receptor modeling is one of statistical methods to achieve reasonable air pollution strategies. In order to maintain and manage ambient air quality, it is necessary to identify sources and to apportion its sources for ambient particulate matters. The main purpose of the study was to survey seasonal trends of inorganic elements in the coarse and fine particles. Second, this study has attempted emission sources qualitatively by a receptor method, the PMF mo-del. After that. both PMF (positive matrix factorization) model and TTFA (target transformation factor analysis) model were applied to compare and to estimate mass contribution of coarse and fine particle sources at the receptor. A total of 138 sets of samples was collected from 1989 to 1996 by a low volume cascade impactor with 9 size fraction stages at Kyung Hee University in Korea. Sixteen chemical species (Si, Ca, Fe, K, Pb, Na, Zn, Mg, Ba, Ni, V, Mn, Cr, Br, Cu. Co) were characterized by XRF. The study result showed that the weighted arithmetic mean of coarse and fine particles were 51.3 and 54.4 $\mu\textrm{g}$/㎥, respectively. Contribution of both particle fractions were esti-mated using TTFA and PMF models. The number of estimated sources was seven according to TTFA model and 8 according to PMF model. Comparison of TTFA and PMF revealed that both methodologies exhibited similar trends in their contribution pattern. However, large differences between contributions were observed in some sour-ces. The results of this study may help to suggest control strategies in local countries where known source profiles do not exist.

• 분석과학
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• 제23권6호
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• pp.607-614
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• 2010

필적을 감정할 경우 음주상태에서 작성된 필적들을 비교해야 하는 어려움에 자주 직면하게 된다. 알콜 섭취에 따른 소뇌 기능 장애로 인하여 가속과 감속, 떨리는 움직임 등의 동작 능력 통제에 장애가 발생하므로 개인 필적에서 상당한 차이가 관찰된다. 음주상태에서 작성된 필적이 기재된 협박메모를 확보하더라도 작성자가 검거된 후 자신이 작성한 것이 아니라고 부인하는 경우 필적감정에 의한 범인 특정이 어렵게 된다. 외국의 많은 연구에서 알콜의 필적에 대한 영향이 다루어지고 있지만 국내에서는 거의 없으며 대부분 통계적 처리 없이 약간 또는 증가와 같이 경험적인 표현에 그치고 있어 통계적인 평가 및 비교가 요구되고 있다. 본 연구에서는 음주에 의한 필적의 변화에 대하여 서명의 길이, 높이와 서명에 포함된 한글 자음 ㄱ, ㄴ을 추출하여 각각의 내각, 외각, 길이비율의 계측값을 통계적 방법을 사용하여 확인하였다.

• 한국산업정보학회논문지
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• 제22권6호
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• pp.95-105
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• 2017

본 연구는 중소기업들의 경쟁력을 증대하기 위하여 평가진단 체크시트 모델을 개발하는 것이다. 평가진단 체크시트 개발 절차는 사전조사(주력기업 조사, 업종특징 분석. 핵심기능 선정 등), 연구개발(핵심기능 체크시트 개발, 핵심기능 향상도구 개발)순으로 진행하였다. 평가모델은 5개 부문(비전과 전략체계, 품질보증과 제품안전, 현장관리 수준, 통계적 공정관리, 개선활동)으로 대별한 후, 각 부문별로 1)인식, 2)체계, 3)운영, 4)검토 및 보완의 4가지 내용으로 구분하여 구성하였다. 본 평가모델은 특히 지방자치단체 내에 산재해 있는 중소기업 중에서 주력 중소기업을 선정하여 집중 육성하는데 많은 기여를 하게 될 것으로 기대되며, 이를 통해 해당 중소기업의 경쟁력이 향상될 것으로 판단된다.

• 한국식품과학회지
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• 제22권3호
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• pp.248-254
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• 1990

식용 돼지췌장 리파제를 두 가지 함량으로 치즈제조시 혼합하여 $7^{\circ},\;13^{\circ},\;21^{\circ}C$에서 숙성시켰다. GC 분석결과 효소처리한 치즈에서는 Control에서 보다 훨씬 많은 양의 저급지방산이 생성되었다. 돼지췌장 리파제를 많이 넣어 $21^{\circ}C$에서 숙성시킨 치즈의 경우 1주 후에 medium flavor 치즈, 3주 후에 거의 sharp flavor 치즈가 특별한 결함없이 생산되었다. 또한 이 효소를 조금 넣은 치즈에서는 양호한 질의 치즈가 많았는데, $7^{\circ},\;13^{\circ},\;21^{\circ}C$에서 3주부터 15주의 숙성기간 중 medium과 sharp flavor 치즈가 생산되었다. 통계분석에 의하면 체다풍미와 caproic acid의 함량에서, 또 체다풍미와 butyric acid, caproic acid 혼합함량 상호관계에서 유의성이 있었다. 적합한 조건을 사용한다면 돼지췌장 리파제는 체다치즈의 숙성을 촉진시키는데 사용 가능한 것으로 사료된다.

• 한국직업건강간호학회지
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• 제25권3호
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• pp.199-207
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• 2016

Purpose: The purpose of this study was to identify the obesity stress, weight bias and health care on Body Mass Index (BMI) in soldiers of non-combat area and to provide data for improving the quality of their life. Methods: This research involved 165 soldiers working in non-combat area. Data collection was conducted from November 1 to 20, 2015. Statistical analysis of the collected data were t-test and ANOVA, $Scheff{\acute{e}}$ method post hoc analysis, Pearson's correlation coefficients, and multiple liner regression using IBM SPSS 22.0. Results: The mean score of obesity stress was moderate ($19.05{\pm}5.28$). The mean score of weight bias was 69.03 and health care was 2.41 points. There are a positive correlation between obesity stress and BMI (r=.19, p<.05). Weight bias (r=-.19, p<.01) and health care (r=-.26, p<.01) among the subjects had negative correlations with BMI. In a multiple liner regression, obesity stress (${\beta}=.18$, p<.05), health care (${\beta}=-.18$, p<.05) were associated with BMI. Conclusion: Based on the findings that obesity stress and health care influence BMI, there is a need to control stress and to properly set proper guidelines on health care for soldiers.

• 치위생과학회지
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• 제18권3호
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• pp.137-146
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• 2018

This systematic review aimed to investigate the effects of periodontal treatment on glycated hemoglobin A (HbA1c) levels in patients with type 2 diabetes who develop periodontal disease. The search of the MEDLINE, Embase, CINAHL, and Cochrane Library databases was completed on April 8, 2018. The study design was based on randomized clinical trials. Scaling and root planing was performed for the test group, whereas no periodontal treatment or simple oral training was performed for the control group. The main outcome variable was the change in HbA1c levels. We used the Review Manager statistical analysis software for the quantitative analysis of selected documents. Meta-analysis was performed using the inverse variance estimation method of the fixed-effect model to estimate the effects of periodontal treatment on HbA1c levels in patients with type 2 diabetes. A total of 1,011 documents were searched using search strategies, and 10 documents were included in the meta-analysis. The meta-analysis of the selected literature showed that periodontal treatment significantly reduced the HbA1c levels in patients with type 2 diabetes who develop periodontal disease (mean difference, -0.34; 95% confidence interval, -0.43 to -0.26; p<0.001). This study aimed to investigate the effects of periodontal treatment on HbA1c levels, which can be used as a basis for the increasing management of diabetic complications. To improve the quality of life and reduce the burden of medical expenses for patients with diabetes, periodontal disease management through nonsurgical periodontal treatment, such as scaling and root planing, is necessary.

• Restorative Dentistry and Endodontics
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• 제27권3호
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• pp.257-269
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• 2002

Objective : The purpose of this study was to evaluate the resin infiltration into dentin of one-bottle adhesive systems and self-etching primer bonded to Class V cavities using confocal laser scanning microscope(CLSM). Material and Methods : Forty Class V cavities were prepared from freshly extracted caries-free Human teeth. These teeth were divided into two groups based on the presence of cervical abrasion: Group I, cervical abrasion : Group II, wedge-shaped cavity preparation. Resin-dentin interfaces were produced with two one-bottle dentin bonding systems-ONE COAT BOND(OCB; Coltene$^R$) and Syntac$^R$SPrint$^{TM}$(SS; VIVADENT)-, one self-etching priming system-CLEARFIL$^{TM}$ SE BOND (SB : KURARAY)- and one multi-step dentin bonding system-Scotchbond$^{TM}$Multi-Purpose (SBMP, 3M Dental Products)-as control according to manufacturers' instructions. Cavities were restored with Spectrum$^{R}$(Dentsply). Specimens were immersed in saline for 24 hours and sectioned longitudinally with a low-speed diamond disc. The resin-dentin interfaces were microscopically observed using CLSM. The quality of resin-infiltrated dentin layers were evaluated by five dentists using 0~4 scale. Results : Confocal laser scanning microscopal investigations using primer labeled with rhodamine B showed that the penetration of the primer occurred along the cavity margins. Statistical analysis using one-way ANOVA followed by Duncan's Multiple Range test revealed that the primer penetration of the group 2(wedge-shaped cavity preparation) was more effective than group 1(cervical abrasion) and that of the gingival interfaces was more effective than the occlusal interfaces. In the one-bottle dentin bonding systems, the resin penetration score of OCB was compatible to SBMP, but those of SS and self-etching priming system, SB were lower than SBMP.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 춘계학술대회
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• pp.727-729
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• 2017

통계청과 보건복지가족부에 따르면 우리나라는 65세 이상 고령인구 비율이 세계 평균치보다 높게 추정되며 이미'고령화 사회(Ageing Society)'에 접어든 것으로 나타났다. 또한, 예상보다 이른 시기에 정보사회에 도달하여 국민들의 삶의 질이 개선되었을 것으로 추정된다. 그러나 고령층은 젊은 층과 달리 새로운 기계에 선뜻 접근하기 어려워 정보의 접근 및 이용에 있어 뚜렷한 차이를 보이고 있어 세대 간 정보 격차(Digital Divide) 현상을 야기 시키고 있다. 이러한 현상을 해결하기 위해 고령층을 위한 음성인식 기반의 스마트 미러 시스템을 구현하였다. 구현한 시스템은 음성인식을 통하여 조명제어 및 날씨, 지하철 시간 정보 조회 서비스를 제공할 수 있다. 구현한 시스템을 통하여 고령층에게 새로운 기계에 대한 접근 용이성을 제공하여 새로운 시대 변화에 동참하는 느낌을 주고 정보를 얻어 생활이 편리하게 만들어 준다는 효과가 기대된다.

• 대한영양사협회학술지
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• 제24권2호
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• pp.169-180
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• 2018

Depression is a major health problem that can lead to mortality. This study was conducted to assess the risk factors associated with depression in a group aged over 65 years by analyzing nationally representative Korean survey data. A total of 1,209 subjects were analyzed among the participants of the 2014 Korean National Health and Nutrition Examination Survey. Statistical methods for a complex sample were applied by using SPSS program(windows ver. 24.0). Depression assessments were carried out by using the 9-item depression module of the Patient Health Questionnaire-9 (PHQ-9). Depression ($PHQ-9{\geq}5$) was more frequently found in females (33.2%) compared to males (16.1%). However, there was no evidence suggesting that characteristics such as residence area, income level and age, except for educational level, were related with depression. The results of the logistic regression analysis showed that i) health habits such as smoking (OR: 2.26) and lack of aerobic physical activity (OR: 1.62), ii) mental health status such as bad self-rating of health status (OR: 4.30), more stress (OR: 8.31), and bad health-related quality of life (by EQ_5D, OR: 3.41), iii) chronic diseases such as obesity (OR: 0.66), hypercholesterolemia (OR: 1.57), anemia (OR: 1.91), and iv) low intake of energy (OR: 1.84) and calcium (OR: 1.71) were significantly associated with depression. This study suggests that certain characteristics of health habits, mental health status, chronic diseases and nutrient intake may be associated with depression. Prospective research on long-term control is needed to establish causal connections among those factors with depression.