• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.4
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• pp.372-389
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• 2008

In this study, we formed a detailed grid at the estuary area of the Nakdong and collected the surface sediments. Particle size analysis and comparison with existing data were conducted to investigate the characteristics of seasonal and long-term changes in the sediments. As a result of investigation, the distribution of the sediments showed a great change per season and was greatly influenced by the quantity of outfall discharge at the Nakdong estuary barrier and the incident wave climate. The sandy sediments showed dominant movement toward the front of Jinwoodo west of the estuary area of the Nakdong due to the influence of the ENE wave, the annually-dominant wave. And the muddy sediments showed deposition by being moved toward the deep open sea along with a current. The present conditions of the sediments at the estuary area of the Nakdong showed great differences from the results of previous studies.

• Journal of Ocean Engineering and Technology
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• v.25 no.3
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• pp.90-95
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• 2011

On April 20, 2010, a well control event allowed hydrocarbon (oil and gas) to escape from the Macondo well onto Deepwater Horizon (DWH), resulting in an exploration and fire on the rig. While 17 people were injured, 11 others lost their lives. The fire continued for 36 hours until the rig sank. Hydrocarbons continued to flow out from the reservoir through the well bore and blowout preventer (BOP) for 87 days, causing an unprecedented oil spill. Beyond Petroleum (BP) and the US federal government tried various methods to prevent the oil spill and to capture the spilled oil. The corresponding responses were very challenging due to the scale, intensity, and duration of the incident that occurred under extreme conditions in terms of pressure, temperature, and amount of flow. On July 15, a capping stack, which is another BOP on top of the existing BOP, was successfully installed, and the oil spill was stopped. After several tests and subsea responses, the well was permanently sealed by a relief well and a bottom kill on September 19. This paper analyzes the subsea responses and engineering efforts to capture the oil, stop the leaking, and kill the subsea well. During the investigation and analysis of subsea responses, information was collected and data bases were established for future accident prevention and the development of subsea engineering.

• Journal of the Korean Vacuum Society
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• v.12 no.1
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• pp.25-34
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• 2003

Deposition behavior of hard amorphous carbon film was investigated by molecular dynamic simulation using Tersoff potential which was suggested for the interaction potential between carbon atoms. When high energy carbon atoms were collided on diamond (100) surface, dense amorphous carbon film could be obtained. Physical properties of the simulated carbon film were compared with those of the film deposited by filtered cathodic arc process. As in the experimental result, the most diamond-like film was obtained at an optimum kinetic energy of the incident carbon atoms. The optimum kinetic energy was 50 eV, which is comparable to the experimental observation. The simulated film was amorphous with short range order of diamond lattice. At the optimum kinetic energy condition, we found that significant amount of carbon atom were placed at a metastable site of distance 2.1 $\AA$. By melting and quenching simulation of diamond lattice, it was shown that this metastatic peak is Proportional to the quenching rate. These results show that the hard and dense diamond-like film could be obtained when the localized thermal spike due to the collision of high energy carbon atom can be effectively dissipated to the lattice.

• Structural Engineering and Mechanics
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• v.63 no.1
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• pp.1-9
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• 2017

Shot peening is a cold surface treatment employed to induce residual stress field in a metallic component beneficial for increasing its fatigue strength. The experimental investigation of parameters involved in shot peening process is very complex as well as costly. The most attractive alternative is the explicit dynamics finite element (FE) analysis capable of determining the shot peening process parameters subject to the selection of a proper material's constitutive model and numerical technique. In this study, Ansys / LS-Dyna software was used to simulate the impact of steel shots of various sizes on an aluminium alloy plate described with strain rate dependent elasto-plastic material model. The impacts were carried out at various incident velocities. The influence of shot velocity and size on the plastic deformation, compressive residual stress and force-time response were investigated. The results exhibited that increasing the shot velocity and size resulted in an increase in plastic deformation of the aluminium target. However, a little effect of the shot velocity and size was observed on the magnitude of target's subsurface compressive residual stress. The obtained results were close to the published ones, and the numerical models demonstrated the capability of the method to capture the pattern of residual stress and plastic deformation observed experimentally in aluminium alloys. The study can be quite helpful in determining and selecting the optimal shot peening parameters to achieve specific level of plastic deformation and compressive residual stress in the aluminium alloy parts especially compressor blades.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.385-390
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• 2014

Background: Lung cancer is the most frequent malignancy of men worldwide. In Ninawa in Iraq, lung cancer ranks first among cancers diagnosed in men. Since no prior studies have been conducted on incidence trends in our population the present investigation of rates during 2000-2010 was therefore performed. Materials and Methods: Registy data for lung cancer cases were collected from the Directorate of Health in Ninawa-Mosul Continuing Medical Education Center. We restricted our analyses to men categorized according to the age groups of 0- 39, 40-49, 50-59, 60-69 and 70+ years. The significance of incidence rate trends during 2000-2010 was tested using Poisson regression. Age-standardized rates (ASR), and age-specific rates per 100,000 population were calculated. Results: A total of 1,206 incident lung cancer were registered among males, accounting for 15.5% of all male cancers registered during 2000-2010. It ranked first throughout the period. Median age at diagnosis was 69 (mean $66.8{\pm}11.0$) years. The incidence rate of all male lung cancers in Ninawa (all ages) decreased from 26.4 per 100,000 in 2000 to 12.7 in 2010 (APC=-6.55%, p<.0001). The incidences in age groups 40-49, 50-59, 60-69 and 70+ decreased in earlier years and recently appeared (2007-2010) stable. The incidence in age group (0-39) remained stable between 2000-2010. Squamous cell carcinoma (SCC)was the most common type of lung cancer, while adenocarcinoma was relatively rare. Conclusions: With the data from Directorate of Health in Ninawa during the period 2000-2010, lung cancer is the most common cancer but generally declining. Among all age groups, the recent incidence of lung cancer remained stable. The SCC predominance suggests change in tobacco habits as an important factor in the trends observed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.41-46
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• 2014

As the radioactive-related incidents have been occurred frequently such as Fukushima nuclear exposure incident, it is always considered radioactivity normal levels in radiation exposure as a most risk components at several government agencies. In this paper, the data were analyzed by information in the data beyond range of the attributes. The clustering analysis method is used by EM and SimpleKMeans algorithm. The experimental results about US Radioactive associated data is depending on the method of data analysis. It can be seen that the method of the algorithm is different depending on local value of the normal range. The governments need to pay attention to increase the investigation frequency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.4C
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• pp.425-432
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• 2007

In this paper, we deals with automatic modulation classification capable of classifying incident signals without a priori information. The 7 key features which have good properties of sensitive with modulation types and insensitive with SNR variation are selected. The numerical simulations for classifying 9 modulation types using the these features are performed. The numerical simulations of the 4 types of modulation classifiers are performed the investigation of classification accuracy and execution time to implement the fast modulation classifier in software radio. The simulation result indicated that the execution time of DTC was best and SVC and MDC showed good classification performance. The prototype was implemented with DTC type. With the result of field trials, we confirmed the performance in the prototype was agreed with the numerical simulation result of DTC.

• Journal of Auto-vehicle Safety Association
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• v.10 no.1
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• pp.20-26
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• 2018

The fatality of rollover accidents in motor vehicle crashes is high despite their low incidence. Through the investigation of a 12-passenger van rollover accident in which 10 passengers were involved, we intend to analyze the correlation between the severity of the injury and the position of the occupants. We collected accident information from medical records, interviews, photo-images of the damaged van, field surveys, and the results of the Korean New Car Assessment Program (KNCAP). Based on the occupants' position, we classified injury sites and estimated injury severity. Passenger injury severity was evaluated by trauma score calculation. The initiation type of the rollover accident was passenger side 'fall-over' and the Collision Deformation Classification (CDC) code for the damaged van was 00TDZO3. The crash of the van involved 10 passengers, with an average age of $16.3{\pm}4.2years$. Few of the occupants had fastened seat belts at the time of the incident, and there was no airbag installed. One patient sustained severe liver injury and another was diagnosed with a fracture of the right humerus. The most common injuries were at the upper extremities and the neck. The average of Injury Severity Score (ISS) was $4.8{\pm}5.9$, and the average ISS of right-seated, mid-seated and left-seated occupants was $7.5{\pm}9.3$, $1.5{\pm}0.7$, and $3.3{\pm}2.1$ respectively (p>0.05). In the rollover (to-passenger side) accident of occupant unfastened, the average ISS of right-seated occupants (near side) was higher, but there was no statistically significant difference.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.103-110
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• 2012

PURPOSES : In Korea, over 70 percent of the land consists of mountainous and rolling area. Thus, tunnels continue its upward trend as road network are extended. In these circumstances, the importance of tunnel has been increased nowadays and then its safety investigation and research should be performed. This study is focus on confirming and improving the safety of tunnel. On tunnel hood, sunglare effect can irritate driver's behavior instantly and this can result in incident. METHODS : The study of this phenomenon is rarely conducted in domestic and foreign papers, so there is no proper measure for this. This study analyzes the driving environment of the effect of sunglare effect on tunnel hood. RESULTS : Traffic accidents stem from complex set of factors. This study build the Traffic Accident Prediction Models to find out the effect of sunglare effect on tunnel's hood. The independent variables are traffic volume, geometric design of road, length of tunnel and road side environment. Using these variables, this model estimates accident frequency on tunnel hood by Poisson regression model and Negative binomial regression model. Although Poisson regression model have more proper goodness of fit than Negative binomial regression model, Poisson regression model has overdipersion problem. So the Negative binomial regression model is used in this analysis. CONCLUSIONS : Consequently, the model shows that sunglare effect can play a role in driving safety on tunnel hood. As a result, the information of sunglare effect should be noticed ahead of tunnel hood so this can prevent drivers from being in hazard situation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4883-4889
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• 2013

Background: The most common incident cancer and cause of cancer-related deaths in women is breast cancer. The Myc gene is upregulated in many cancer types including breast cancer, and it is considered as a potential anti-cancer drug target. The present study was conducted to evaluate the Myc (gene and protein) expression pattern in an experimental mammary tumour model in rats. Materials and Methods: Thirty six Sprague Dawley rats were divided into: Experimental group (26 animals), which received the chemical carcinogen N-methyl nitrosourea (MNU) and a control group (10 animals), which received vehicle only. c-Myc oncoprotein and its mRNA expression pattern were evaluated using immunohistochemistry (IHC) and semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), respectively, in normal rat mammary tissue and mammary tumours. The rat glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as internal control for semi-quantitative RT-PCR. Results: Histopathological examination of mammary tissues and tumours from MNU treated animals revealed the presence of premalignant lesions, benign tumours, in situ carcinomas and invasive carcinomas. Immunohistochemical evaluation of tumour tissues showed upregulation and heterogeneous cellular localization of c-Myc oncoprotein. The expression levels of c-Myc oncoprotein were significantly elevated (75-91%) in all the tumours. Semi-quantitative RT-PCR revealed increased expression of c-Myc mRNA in mammary tumours compared to normal mammary tissues. Conclusions: Further large-scale investigation study is needed to adopt this experimental rat mammary tumour model as an in vivo model to study anti-cancer strategies directed against Myc or its downstream partners at the transcriptional or post-transcriptional level.