• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3341-3355
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• 2016

Background: A recent WHO data report on mortality attributable to tobacco use including cigarette smoking indicated a very high burden of deaths in Asia and that people often initiate smoking as early as young adolescents. The objectives of this study were to systematically review peer-reviewed articles on cigarette smoking initiation among Asian adolescents and to develop a conceptual model of factors influencing smoking initiation by integrating all relevant factors based on existing data. Materials and Methods: Following a PRISMA guideline, a systematic review of articles published between 2005 and June 2015 was conducted using 5 databases on cigarette smoking initiation among adolescents (aged 10-19 years) living in Asia. We summarized the main findings of each study according to our research questions and data that emerged during the data extraction process. Analysis and categorization were based on the TTI and TPB models and classification of factors extracted from the study, were as follows: personal factors, social factors, broader environmental factors, mediators, and intention to initiate smoking and smoking behavior. Results: Of 1,227 identified studies, only 20 were included in this review. Our findings found that the mean age of cigarette smoking initiation ranged from 10 to 14 years and those who are more likely to initiate smoking are male, older adolescents, adolescents with low parental SES, individuals with low parental monitoring, low parental education level and having no discussion on smoking at home, those living in public housing and those exhibiting health-risk behavior. Our study also revealed that the risk of smoking initiation increased when they are exposed to smokers, influenced by peers, exposed to tobacco advertisements, receive pocket money, have lack of knowledge about smoking, have poor school performance, have a family conflict and have psychological problems. The conceptual model developed demonstrated complex networks of factors influencing initiation. Conclusions: This systematic review presents various factors influencing smoking initiation of the Asian adolescents and provides a conceptual framework to further analyze factors. Future studies should have a standard measure of smoking initiation, should analyze interactions and the intensity of relationships between different factors or variables in the conceptual model. This will in turn consolidate the understanding of the different factors affecting smoking initiation and will help to improve interventions in this area.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제22권5호
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• pp.306-316
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• 1989

We examined the state of Korean pomfret(Pampus echinogaster) in Korean waters and considered the management strategy of the stock based on the theory yield Per recruit. It is not facile to discriminate Korean pomfret distributed in Korean waters from silver pomfret (p. argenteus) due to the similarities in their external morphologies. For this rea- son, Korean pomfret has been treated in silver pomfret in fisheries statistics of Korea. In this study, we asserted Korean pomfret from pomfrets caught commercially by the morphology, from which we recognized that Korean pomfret took $60\~70\%$ in catch(in weight) and that the smaller the body length, the higher the proportion of Korean pomfret. Parameters estimated for Korean pomfret were as follows: natural mortality(M) = 0.6, fishing mortality(F) =0.924(mean value for $1986\~1988$), age at recruit to fishery($t_r$) =0.19 yrs, age at first capture($t_c$) : 0.49 yrs, and the rate of recruit of age-0 fish to fishery(Q) = 0.29. The results obtained from the theory of yield per recruit indicated that the present state of stock was below the optimum level of exploitation and that the control of fishing intensity rarely had an effect on the increasing of yield. Accordingly, we conclude that proper management can be made by increasing the current age of 0.49 yrs at first capture to 1.5 yrs.

• Journal of the Korean Society of Food Science and Nutrition
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• 제41권8호
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• pp.1112-1117
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• 2012

In this study, the effects of a rice diet and bread diet on plasma triglyceride, insulin and ghrelin levels during low-intensity endurance exercise and recovery were investigated. Ten male students randomly received 2 different treatments: the rice diet and bread diet. On the first day, the participants performed 2 hours of treadmill running with 6% uphill at 50% $VO_{2max}$ after breakfast and then each consumed lunch and dinner. Blood samples were drawn 120 min before exercise and, right before exercise and, 60 min and 120 min after the start of exercise. On the second day, blood samples were drawn prior to breakfast, immediately after breakfast and, 60 min, 120 min, and 180 min after breakfast with no exercise treatment. Plasma triglyceride, ghrelin, glucose, and insulin levels were not significantly different between the two treatment groups on the first day. In addition, there was no difference in the carbohydrate and fat oxidation rate between the two treatments groups. However, plasma triglyceride levels in subjects that received the rice diet were significantly reduced by 14% when compared to subjects that received the bread diet at 180 min after consuming the breakfast diet on the second day. Ghrelin levels were significantly higher for subjects that received the rice diet than subjects that were given the bread diet. However, insulin in participants that consumed the rice diet was significantly lower than those that received the bread diet at 60 min and 120 min after consumption of the breakfast diet on the second day. Glucose levels in the subjects that were given the rice diet were significantly reduced by 10.3% when compared with participants that received the bread diet at 60 min. Therefore, the results of the study showed that a rice diet may be more effective in preventing cardiovascular diseases than a bread diet when combined with exercise.

• Journal of Oral Medicine and Pain
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• 제40권2호
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• pp.55-62
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• 2015

Purpose: The aims of this study were to evaluate the differences in subjective symptoms, clinical characteristics, distribution according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) subgroup, psychological profile of TMD patients, and to identify the prevalence and trend according to age. Methods: A total of 1,052 patients (261 men and 791 women; mean age, $34.40{\pm}15.73$ years) who visited the Orofacial Pain Clinic of the Department of Oral Medicine, Seoul National University Dental Hospital complaining of TMD symptoms of were evaluated. All patients were questioned for medical history, clinical symptoms and contributing factors. Clinical examination and patient grouping based on RDC/TMD was conducted. Radiographies were taken. The Korean version of RDC/TMD axis II and Symptom Checklist-90-Revision (SCL-90-R) were administered to evaluate pain-related disability level and psychological status of the patients. Results: Prevalence peaked in the 20-year-old age group. There were more women than men in all groups. The highest T-score among SCL-90-R dimensions was somatization in each group, except for teenagers who showed the highest T-score in interpersonal sensitivity. The 30-year-old age group showed the highest distribution of high disability based on the graded chronic pain scale. Age was positively associated with pain intensity (r=0.100), number of positive muscles on palpation (r=0.137) and negatively associated with maximum mouth opening (r=-0.168). Conclusions: Subjective symptoms and clinical characteristics of TMD patients show distinct tendencies according to different age groups. Treatment should be customized and personalized according to age for efficient symptom resolution and patient satisfaction.

• Transactions of the Korean Society of Mechanical Engineers B
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• 제35권12호
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• pp.1375-1381
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• 2011

Combustion processes in an optically-accessible single-cylinder heavy-duty diesel engine equipped with a highpressure common-rail injection system were investigated for JP-8 and diesel. Direct imaging and two-color thermometry were employed to verify the emission trend for both fuels. The combustion process was characterized by image analysis with focus on luminosity. The results of two-color thermometry were analyzed on the basis of the flame temperature and KL factor distribution. Analysis of the combustion process by direct imaging showed that the ignition delay was longer for JP-8 than for diesel, while the flame was extinguished rapidly. Analysis of the flame luminosity showed that the combustion intensity was higher for diesel and that the flame lasted for a longer duration in this case. Two-color thermometry results showed that the high-temperature region extended over a large area during JP-8 combustion, implying the formation of a large amount of $NO_x$. In addition, the KL factor showed low level over a large area and relatively homogeneous in the case of JP-8 combustion, which implied that less smoke was produced when using this fuel.

• Journal of the Korean Vacuum Society
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• 제17권1호
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• pp.40-45
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• 2008

We present the effect of Ga-doping on the electrical, structural and optical properties of ZnO layers with a thickness of ${\sim}500nm$ deposited on glass substrates. Polycrystalline ZnO and Ga-doped ZnO (GZO) layers were deposited by radio frequency (rf) magnetron sputtering at room temperature. Based on the X-ray diffraction (XRD) and transmission electron microscopy (TEM) data, the crystalline quality of Ga-doped ZnO film was improved and GZO film has a preferred orientation along with the (002) crystal direction. The transmittance of the GZO film was enhanced by 10% in the visible region from that of the ZnO film. From photoluminescence (PL) data, the ratio of intensity of near band edge (NBE) emission to deep level (DL) emission was as high as 2.65:1 and 1.27:1 in the GZO and ZnO films, respectively. The res istivities of GZO and ZnO films were measured to be 1.27 and 1.61 $\Omega{\cdot}cm$, respectively. The carrier concentrations of ZnO and GZO film were approximately 1018 and 1020 $cm^2$/Vs, respectively. Based on our experimental results, the Ga-doping improves the electrical, structural and optical properties of ZnO film with potential application.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2011년도 학술발표회
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• pp.18-18
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• 2011

Climate change is impacting and will increasingly impact both the quantity and quality of the world's water resources in a variety of ways. In some areas warming climate results in increased rainfall, surface runoff, and groundwater recharge while in others there may be declines in all of these. Water quality is described by a number of variables. Some are directly impacted by climate change. Temperature is an obvious example. Notably, increased atmospheric concentrations of $CO_2$ triggering climate change increase the $CO_2$ dissolving into water. This has manifold consequences including decreased pH and increased alkalinity, with resultant increases in dissolved concentrations of the minerals in geologic materials contacted by such water. Climate change is also expected to increase the number and intensity of extreme climate events, with related hydrologic changes. A simple framework has been developed in New Zealand for assessing and predicting climate change impacts on water resources. Assessment is largely based on trend analysis of historic data using the non-parametric Mann-Kendall method. Trend analysis requires long-term, regular monitoring data for both climate and hydrologic variables. Data quality is of primary importance and data gaps must be avoided. Quantitative prediction of climate change impacts on the quantity of water resources can be accomplished by computer modelling. This requires the serial coupling of various models. For example, regional downscaling of results from a world-wide general circulation model (GCM) can be used to forecast temperatures and precipitation for various emissions scenarios in specific catchments. Mechanistic or artificial intelligence modelling can then be used with these inputs to simulate climate change impacts over time, such as changes in streamflow, groundwater-surface water interactions, and changes in groundwater levels. The Waimea Plains catchment in New Zealand was selected for a test application of these assessment and prediction methods. This catchment is predicted to undergo relatively minor impacts due to climate change. All available climate and hydrologic databases were obtained and analyzed. These included climate (temperature, precipitation, solar radiation and sunshine hours, evapotranspiration, humidity, and cloud cover) and hydrologic (streamflow and quality and groundwater levels and quality) records. Results varied but there were indications of atmospheric temperature increasing, rainfall decreasing, streamflow decreasing, and groundwater level decreasing trends. Artificial intelligence modelling was applied to predict water usage, rainfall recharge of groundwater, and upstream flow for two regionally downscaled climate change scenarios (A1B and A2). The AI methods used were multi-layer perceptron (MLP) with extended Kalman filtering (EKF), genetic programming (GP), and a dynamic neuro-fuzzy local modelling system (DNFLMS), respectively. These were then used as inputs to a mechanistic groundwater flow-surface water interaction model (MODFLOW). A DNFLMS was also used to simulate downstream flow and groundwater levels for comparison with MODFLOW outputs. MODFLOW and DNFLMS outputs were consistent. They indicated declines in streamflow on the order of 21 to 23% for MODFLOW and DNFLMS (A1B scenario), respectively, and 27% in both cases for the A2 scenario under severe drought conditions by 2058-2059, with little if any change in groundwater levels.

• Restorative Dentistry and Endodontics
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• 제25권4호
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• pp.509-526
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• 2000

It is known that injuries to the dentin have a corresponding inflammatory effect on the pulp and these inflammatory effects frequently result in pulpal pathoses due to progressive degradation of pulpal connective tissue. It was supposed that the tissue degradation in different inflammatory process was controlled by proteinase activity and antiproteinase activity. Therefore, the purpose of this study was to examine the pulp and periapical pathoses in terms of the activities of proteinase and proteinase inhibitor, 37 pulpal tissues were divided by clinical diagnostic criteria into normal pulp, acute inflamed pulp, and chronic inflamed pulp, and then those groups were subdivided by histopathological findings into 5 pulpal pathoses groups, i.e. normal pulp (P1, n=8), chronic pulpitis with fibrotic change (P2, n=2), chronic pulpitis with dystrophic calcification (P3, n=11), chronic pulpitis with pulp abscess (P4, n=7), acute pulpitis with necrotic change (P5, n=4), 26 periapical tissues were also divided by ordinary histopathological findings into 3 periapical pathoses group, i.e., granuloma (A1, n=17), cyst (A2, n=2) and abscess (A3, n=7). The activities of proteinases (cathepsin G, MMP-3) and proteinase inhibitors (${\alpha}1$-AT, TIMP-1 and, SLPI) were evaluated by RT-PCR and immunohistochemical methods. The results were as follows. 1. Generally, the intensity of immunohistochemical staining of proteinases and proteinase inhibitors increased in P2 and P5 groups compared to P1 group. 2. The immunohistochemical stain of proteinases and proteinase inhibitors was intensely detected in P2 group, showing low inflammatory reaction and low tissue degradation, but it was reduced in P3 and P4 groups, showing severe tissue degradation. 3. The distribution of proteinases and proteinase inhibitors in pulpal pathoses was consistently presented by immunohistochemical staining, while the expression of proteinase and/or proteinase inhibitors mRNAs in pulpal pathoses was occasionally detected by RT-PCR methods. 4. RT-PCR of proteinase and proteinase inhibitors was usually positive in P2, showing rare tissue degradation, but it was almost negative in P3 and P4, showing severe tissue degradation. 5. We presume that the reason why the level of proteinase and proteinase inhibitors was so sparse in RT-PCR method is due to the abrupt decrease of mRNA synthesis or degradation of synthesized mRNA of proteinase and/or proteinase inhibitors depend on the inflammatory reaction and/or on the degradation of pulp tissues(P3, P4). 6. Pulpal pathoses groups showed significant lower RT-PCR detection of proteinases and proteinase inhibitors than the periapical pathoses group(p<0.05), and there is no significant difference among the periapical pathoses groups(p>0.05).

• Journal of KIISE:Software and Applications
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• 제27권7호
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• pp.731-741
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• 2000

This paper proposes a method to detect a facial region and extract facial features which is crucial for visual recognition of human faces. In this paper, we extract the MER(Minimum Enclosing Rectangle) of a face and facial components using projection analysis on both edge image and binary image. We use an active contour model(snakes) for extraction of the contours of eye, mouth, eyebrow, and face in order to reflect the individual differences of facial shapes and converge quickly. The determination of initial contour is very important for the performance of snakes. Particularly, we detect Minimum Enclosing Rectangle(MER) of facial components and then determine initial contours using general shape of facial components within the boundary of the obtained MER. We obtained experimental results to show that MER extraction of the eye, mouth, and face was performed successfully. But in the case of images with bright eyebrow, MER extraction of eyebrow was performed poorly. We obtained good contour extraction with the individual differences of facial shapes. Particularly, in the eye contour extraction, we combined edges by first order derivative operator and zero crossings by second order derivative operator in designing energy function of snakes, and we achieved good eye contours. For the face contour extraction, we used both edges and grey level intensity of pixels in designing of energy function. Good face contours were extracted as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제18권12호
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• pp.712-721
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• 2017

Recently, the intensity and frequency of floods has increasing worldwide, and flood disasters have become a big problem. Flood disasters, which account for the largest portion of disasters, are floods accompanied by typhoons and localized heavy rainfall. As a result, they cause damage of levee overtopping, in which the water level of a river rises to the levee crown. Therefore, countermeasures are essential and necessary because of the damage to the facility itself as well as to life and other property. The damage magnitude depends on the collapse of the levee. A levee that is difficult to collapse will reduce the discharge inland significantly. Accordingly, the protection of the inland slope, where the collapse of the levee is initiated, is one of the most important countermeasures In this study, revetments with various porosity and forms were suggested and hydraulic experiments were carried out for each type. The hydraulic experiments showed that the stability of a revetment in an inland slope is strongly correlated with the weight per unit area of the revetment. The relationship between the critical velocity, which is the velocity at the moment of leaving the revetment, and the weight per unit area was derived. Through this study, by applying the nature friendly revetment, which has not yet been applied to Korea, it is expected that life and property damage caused by levee overtopping during flooding can be reduced, and a nature friendly river space can be constructed.