• Research in Plant Disease
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• v.8 no.4
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• pp.199-206
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• 2002

It was investigated on the relationship of the rice blast epidemics and the real-time meteorological factors, at the experimental paddy field in 1997. Weather factors(temperature, relative humidity, irradiation, precipitation, the direction of wind, wind speed, soil temperature and leaf-wetness, etc) were measured by using the automated weather station. The most influenced weather factor to blast epidemics, was the average max-temp($R^2$= 0.95) during 10 days before leaf blast epidemics, while the least thing was wind speed($R^2$= 0.24). The most potential weather factors correlated with the blast epidemics were T-ave(average temperature), T-max(maximum temperature), RH(Relative Humidity) and RD(Relative Humidity > 90% hrs). A statistics model(the regression equation) of the blast epidemics with the potential weather factors, was established as tallows ; Y = -3410.91 - 23.91 $\times$ T-ave ＋ 28.56 $\times$ T-max ＋ 41.0 $\times$ RH - 3.75 $\times$ RD, ($R^2$= 0.99). (T-ave >= 19$^{\circ}C$, T-max - T-ave >= 5.2$^{\circ}C$ and RH% >= 90.4%). According to the fitness test($\chi$$^2$) of the model, the observed blast disease severity was quite close to those expected.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.87-97
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• 2018

Turfgrass provides various beneficial effects to our societies such as recreation, aesthetic components, and other public service. Diseases in turfgrass is the major issue, which cause quality problems in golf courses, playgrounds, parks and cultivation areas, and tremendous cost is required to prevent the diseases. Research activity and investigation for turfgrass disease remain to be further attributed when compared to other crops in Korea. In this study, we present previously reported turfgrass diseases researches, especially caused by fungal pathogens, and review the history of turfgrass research activity in Korea to contribute future turfgrass research direction. Research papers were searched and analyzed using Korea Educational and Research Information Service (www.riss.kr). More than eighty papers presented turfgrass diseases and among the papers, 50% were published in Korean Journal of Turfgrass. Half of the papers reported turfgrass diseases control. Research articles about large patch disease were the majority (36%), followed dollar spot (18%), Pythium blight (10%) and Typhular blight (8%). Number of the first disease reports in Korea were total fifteen. Total 542 fungicides have been registered in Korea to prevent turfgrass diseases and most of the fungicides were for brown patch, rust, yellow patch, dollar spot, snow mold, summer patch, anthracnose, Pythium blight, powdery mildew and algae. And we will also need to conduct ecological studies on turf diseases and to develop control methods with improved efficacy and environmentally-friend sound. Researches on epidemiology of turfgrass diseases which deals with the incidence, distribution, and interactions with other factors will be also greatly favored for precise control prescription, timing of control and use of less pesticides.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4335-4338
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• 2015

Background: Oral cancer is the third most common malignancy in Saudi Arabia, the highest incidence of which is reported from Jazan province. The objective of this study was to evaluate the association of various locally used substances, especially shamma, with oral cancer in the Jazan region of Saudi Arabia. Materials and Methods: A hospital-based case-control study was designed and patient records were scanned for histologically confirmed oral cancer cases. Forty eight patients who were recently diagnosed with oral cancer were selected as cases. Two healthy controls were selected for each observed case and they were matched with age (+/- 5 years) gender and location. Use of different forms of tobacco such as cigarettes, pipe-smoking and shamma (smokeless-tobacco) was assessed. Khat, a commonly used chewing substance in the community was also included. Descriptive analysis was first performed followed by multiple logistic regression (with and without interaction) to derive odds ratios (ORs) and 95% confidence interval (CIs). Results: Mean age of the study sample (56% males and 44% females) was 65.3 years. Multinomial regression analysis revealed that shamma use increased the odds of developing oral cancer by 29 times (OR=29.3; 10.3-83.1). Cigarette (OR=6.74; 2.18-20.8) was also seen to have an effect. With the interaction model the odds ratio increased significantly for shamma users (OR=37.2; 12.3-113.2) and cigarette smokers (OR=10.5; 2.88-3.11). Khat was observed to have negative effect on the disease occurrence when used along with shamma (OR=0.01; 0.00 - 0.65). Conclusions: We conclude that shamma, a moist form of smokeless tobacco is a major threat for oral cancer occurrence in the Jazan region of Saudi Arabia. This study gives a direction to conduct further longitudinal studies in the region with increased sample size representing the population in order to provide more substantial evidence.

• The Journal of Engineering Geology
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• v.5 no.1
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• pp.59-74
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• 1995

It is well known that the hypocentral parameters inside the seismic array are well determined using HYPO71PC Programs. These programs, however, do not woik well for the non-evenly distribution of the seismic stations and/or the seismic events outside the seismic array. Furthermore it is very difficult to determine the exact locations of small events in North Korea since there is no seismological data exchange between South and North Koreas. We used the polarization method of the single-station with 3-component in addition to HYPO71PC(IASPEI's Program) in order to determine the source parameters of shallow-focus earthquakes outside the seismic array. First of all, we tested the interior events of the Uisung earthquake, April 14, 1991 and the Mt. Keyryong earthquakes, Feorirary 12, 1994, and two exterior events of W. Pyoungyang earthquake, Noventer 12, 1992, and Yellow Sea earthquake, July 26, 1994 to investigate the convergence and divergence to calculate the source parameters. We have found that the source determination outside the seismic array never converges to the exact location whereas the any events inside the array quickly converge to the exact location. The seismic events outside the array such as two events Vladivostok and East Sea, and the Yellow Sea event are more accurately determined using the polarization method. Estimating the source azimuth is carried out by estimating the polarization direction of the interesting phases and the range estimate is made frum the relative timing of different phases. The polarization method is verified by fmding that the estimates of azimuths and incidence angles by the polarization method are identical with those of the synthetic seismograms of the modellings using the generator program.

• Journal of Korean Academy of Nursing
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• v.26 no.3
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• pp.632-652
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• 1996

It has been noted that a genetic alteration of cells influenced by unhealthy lifestyle in addition to a series of other carcinogens increases the incidence of various neoplasmic diseases. Therefore the importance of a lifestyle that minimizes such an impact on health should be emphasized. Since stomach cancer, the most common neoplasmic disease in Korea, is related to personal lifestyle and as there is a possibility of its recurrence, patients with stomach cancer need to lead a healthy lifestyle. Also the quality of life which patients experience is negatively affected by the side effects of treatments and the possibility of recurrence. Therefore an effective nursing intervention to enhance quality of life and encourage healthy lifestyle is needed. The purpose of this study is to provide a basis for nursing intervention strategies to promote health and thus enhance quality of life. A hypothetical model for this purpose was constructed based on Pender's Health Promotion Model and Becker's Health Belief Model, with the inclusion of some influential factors such as hope for quality of life and health promoting behavior. The aims of study were to : 1) evaluate the effectiveness of patient's cognitive-perceptual factors on health promoting behaviors and quality of life ; 2) examine the causal relationships among perceived benefit, perceived barrier, perceived susceptibility and severity, internal locus of control, perceived health status, hope, health concept, self efficacy, self esteem health promoting behaviors & quality of life ; 3) build and test a global hypothetical model. The subjects for this study were 164 patients who were being treated for stomach cancer were approached in the outpatient clinic on a University Hospital. The data from the completed questionnaires were analyzed using Linear Structural Relationships (LISREL). The results of research are as follows : 1) Hypothetical model and the modified model showed a good fit to the empirical data, revealing considerable explanational power for health promoting behaviors(54.9%) and quality of life(87.6%) 2) Self efficacy and hope had significant effects on health promoting behaviors. Of these, hope was affected indirectly through self efficacy and self esteem. 3) Perceived health status, hope and self esteem had significant direct effect on the quality of life. Of these variables, perceived health status was the most essential factor affecting general satisfaction in life. 4) Self-efficacy, as a mediating variable, was positively affected by perceived benefit and hope. 5) Self-esteem, as a mediating variable, was positively affected by perceived health status and hope. 6) Hope was the main variable affecting self efficacy, self esteem, health promoting behaviors and quality of life. The derived model in this study could effectively be used as a reference model for further study and could suggests a direction for nursing practices

• The Journal of the Acoustical Society of Korea
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• v.38 no.6
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• pp.637-650
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• 2019

This paper analyzes the limitations of binaural sound that is reproduced with headphones based on Ambisonics for Virtual Reality (VR) audio. VR audio can be provided with binaural sound that compensates head rotation of a listener. Ambisonics is widely used for recording and reproducing ambient sound fields around a listener in VR audio, and the First order Ambisonics (FOA) is still being used for VR audio because of its simplicity. However, the maximum frequencies with this order is too low to perfectly reproduce ear signals, and thus the binaural reproduction has inherent limitations in terms of spectrum and sound localization. This paper investigates these limitations by comparing the signals arrived at ear positions in the reference field and the reproduced field. An incidence wave is defined as a reference field, and reproduced over virtual loudspeakers. Frequency responses, inter-aural level differences, and inter-aural phase differences are compared. The results show, above the maximum cut off frequency in general, that the reproduced levels decrease, and the horizontal localization can be provided only around the forward direction.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.77-82
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• 2017

Recently, the possibility of abnormal waves of which height is greater than design wave height have been increased due to the climate change, and therefore it has been urgent to secure the stability for harbor structures. As a countermeasure for improving the stability of conventional caisson breakwaters, a method has been proposed in which adjacent caissons are interlocked with each other to consecutively resist the abnormal wave forces. In order to reflect this research trend, the reduction effect of the maximum wave force resulted from introducing a long caisson has been presented in the revision to the design criteria for ports and fishing harbors and commentary. However, no method has been proposed to evaluate the stability of interlocking caisson breakwater. In this study, we consider the effect of the phase difference of the oblique incidence of the wave based on the linear wave theory and apply the Goda pressure formula for considering design wave pressure distribution in the vertical direction. Sliding stability assessment formula of an interlocking caisson breakwater is proposed for regular, irregular, and multi-directional irregular wave conditions.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.79-82
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• 2007

Tracheobronchial rupture due to blunt chest trauma is an uncommon injury although the incidence is increasing. Early diagnosis and primary repair of tracheobronchial rupture not only restore a normal lung function but also avoid the difficulties and complications associated with delayed diagnosis and repair We present one case of the tracheal transsection caused by traffic accident. Patient suffered from progressive dyspnea, subcutaneous emphysema on the neck and anterior chest wall and tension pneumothorax at both sides were noted. Although both closed thoracostomy were done, massive air leakage through the chest tube continued and subcutaneous emphysema spread to the anterior abdominal wall and scrotum and the degree of dyspnea aggravated. With the impression of tracheobronchial injury, we performed the emergency operation. Preoperative bronchoscopy at the operation room was proceeded, which revealed the trachea was near totally transsected in transverse direction. Operation was performed through collar incisiion on the anterior neck, and the trachea was anastomosed with 4-0 $Vicryl^{(R)}$ interruptedly. Postoperative course were uneventful and patient discharged without any complications.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.450-458
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• 2019

Passive cavitation imaging method is used to observe the ultrasonic waves generated when a group of bubbles collapses. A problem with passive cavitation imaging is a low resolution and large side lobe levels. Since ultrasound signals generated by passive cavitation take the form of a pulse, the amplitude distribution of signals received across the receive channels varies depending on the direction of incidence. Both the centroid and flatness were calculated to determine weights at imaging points in order to discriminate between the main and side lobe signals from the signal amplitude distribution of the received channel data and to reduce the side lobe levels. The centroid quantifies how the channel data are distributed across the receive channel, and the flatness measures the variance of the channel data. We applied the centroid weight and the flatness to the passive cavitation image constructed using the delay-and-sum focusing and minimum variance beamforming methods to improve the image quality. Using computer simulation and experiment, we show that the application of weighting in delay-and-sum and minimum variance beamforming reduces side lobe levels.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.446-457
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• 2020

Crescentic sand bar in the coastal zone of eastern Korea is a common morphological feature and the rhythmic patterns exist constantly except for high wave energy events. However, four consecutive typhoons that directly and indirectly affected the East Sea of Korea from September to October in 2019 impacted the formation of longshore uniform sand bar and overall shoreline retreats (approx. 2 m) although repetitive erosion and accretion patterns exist near the shoreline. Widely used XBeach to predict storm erosions in the beach is utilized to investigate the morphological response to a series of storms and each storm impact (NE-E wave incidence). Several calibration processes for improved XBeach modeling are conducted by recently reported calibration methods and the optimal calibration set obtained is applied to the numerical simulation. Using observed wave, tide, and pre & post-storm bathymetries data with optimal calibration set for XBeach input, XBeach successfully reproduces erosion and accretion patterns near MSL (BSS = 0.77 (Erosion profile), 0.87 (Accretion profile)) and observed the formation of the longshore uniform sandbar. As a result of analysis of simulated total sediment transport vectors and bed level changes at each storm peak Hs, the incident wave direction contributes considerable impact to the behavior of crescentic sandbar. Moreover, not only the wave height but also storm duration affects the magnitude of the sediment transport. However, model results suggest that additional calibration processes are needed to predict the exact crest position of bar and bed level changes across the inner surfzone.