• Journal of the Korean Society for Railway
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• v.14 no.5
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• pp.433-441
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• 2011

It is a fact that the straightening of track alignment is one of the undoubted ways to improve the train speed on conventional lines, while that requires huge investment resources. Therefore, the operation of a tilting train as well as the minimum improvement of track is suggested as an effective and economical alternative way for the speed-up of conventional lines. Since a driving mechanism of tilting train is different from those of existing trains, in order to make sure its operation safety and stability on conventional line, the performance of track and roadbed must be preferentially evaluated on the conventional line. Furthermore, it is necessary to estimate the tilting-train-induced roadbed response in detail since the roadbed settlement can lead to the track deformation and even derailment. In this research, the patterns of wheel load and lateral force were monitored and analyzed through the field tests, and the derailment coefficient and degree of wheel off-loading were calculated in order to evaluate the tilting train running safety depending on the running speeds (120km~180km) on the conventional line. Moreover, roadbed pressure, settlement and acceleration were also observed as tilting-train-induced roadbed responses in order to estimate the roadbed stability depending on the running speeds. Consequently, the measured derailment coefficient and degree of wheel off-loading were satisfied with their own required limits, and all of the roadbed responses were less than those of existing high-speed train (KTX) over an entire running speed range considered in this study. As a result of this study, the tilting train which will be operated in combination with existing trains is expected to give no adverse impact on the conventional line even with its improved running speed.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.13-22
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• 2017

Objectives: The objective of this study was to evaluate the exposure levels of door-to-door deliverers to fine particulate matter (PM2.5). Another objective was to confirm the general working patterns of door-to-door deliverers via survey. Methods: In the city of Daegu, ten door-to-door deliverers who wished to join the study were recruited. The general working characteristics of door-to-door deliverers were surveyed using self-reported questionnaires. In the cabin of each car driven by a deliverer, a real-time PM2.5 sampler (Sidepak, Model AM510, TSI Inc., MN, USA) and a GPS device (GPS 741, Ascen, Korea) were installed. Each deliverer was monitored for four days per week so that each day could be monitored at least four times. Results: A total of 40 measurements of PM2.5 concentrations were taken during delivery of parcels. The average exposure levels of door-to-door deliverers to PM2.5 was $44.62{\mu}g/m^3$ ($7-9443{\mu}g/m^3$. Exposure levels to PM2.5 according to the day of the week and coverage areas were not significantly different (p>0.05). Door-to-door deliverers using trucks with older diesel engines manufactured before 2006 had significantly higher exposure levels to PM2.5 than in the case of trucks with diesel engines manufactured after 2006 (p<0.05). Many of the door-to-door deliverers reported the status of having windows open during the delivery task. During delivery services, the working hours spent in residential areas were higher than on roadsides, but exposure levels to PM2.5 in residential areas and on roadsides were $46.17{\mu}g/m^3$ and $49.90{\mu}g/m^3$, respectively. Real-time PM2.5 exposure levels were significantly different between roadways and residential areas (p<0.001). Conclusions: PM2.5 exposure levels of door-to-door deliverers were found to be affected by higher vehicle emissions from the roadsides near their vehicle during deliveries and while driving to other locations compared to by PM2.5 from the diesel engines of their own trucks. Particle concentrations from roadsides and emissions from nearby vehicles through open windows were the main source of PM2.5.

• Journal of Korea Spatial Information System Society
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• v.10 no.3
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• pp.55-65
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• 2008

For obtaining telematics traffic information(travel time or speed in an individual link), there are many kinds of devices to collect traffic data. Since the GPS satellite signals have been released to civil society, thank to the development of GPS technology, the GPS has become a very useful instrument for collecting traffic data. GPS can reduce the cost of installation and maintenance in contrast with existing traffic detectors which must be stationed on the ground. But. there are Problems when GPS data is applied to the existing filtering techniques used for analyzing the data collected by other detectors. This paper proposes a method to provide users with correct traffic information through filtering abnormal data caused by the unusual driving in collected data based on GPS. We have developed an algorithm that can be applied to real-time GPS data and create more reliable traffic information, by building patterns of past data and filtering abnormal data through selection of filtering areas using Quartile values. in order to verify the proposed algorithm, we experimented with actual traffic data that include probe cars equipped with a built-in GPS receiver which ran through Gangnam Street in Seoul. As a result of these experiments, it is shown that link travel speed data obtained from this algorithm is more accurate than those obtained by existing systems.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.121-132
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• 2018

Weather is an important factor affecting roadway transportation in many aspects such as traffic flow, driver 's driving patterns, and crashes. This study focuses on the relationship between weather and road surface condition and develops a model to estimate the road surface condition using machine learning. A road surface sensor was attached to the probe vehicle to collect road surface condition classified into three categories as 'dry', 'moist' and 'wet'. Road geometry information (curvature, gradient), traffic information (link speed), weather information (rainfall, humidity, temperature, wind speed) are utilized as variables to estimate the road surface condition. A variety of machine learning algorithms examined for predicting the road surface condition, and a two - stage classification model based on 'Random forest' which has the highest accuracy was constructed. 14 days of data were used to train the model and 2 days of data were used to test the accuracy of the model. As a result, a road surface state prediction model with 81.74% accuracy was constructed. The result of this study shows the possibility of estimating the road surface condition using the existing weather and traffic information without installing new equipment or sensors.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.1
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• pp.8-17
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• 2023

In conventional liquid crystal display(LCD) manufacturing process, Indium Tin Oxide(ITO) as transparent electrode and rubbing process of polyimide as alignment layer are essential process to apply electric field and align liquid crystal molecules. However, there are some limits that deposition of ITO requires high vacuum state, and rubbing process might damage the device with tribolectric discharge. In this paper, we made nanocomposite with PEDOT:PSS and MWNT to replace ITO and constructed alignment layer by nano imprint lithography with nano wrinkle pattern, to replace rubbing process. These replacement made that only one PEDOT:PSS/MWNT film can function as two layers of ITO and polyimide alignment layer, which means simplification of process. Transferred nano wrinkle patterns functioned well as alignment layer, and we found out lowered threshold voltage and shortened response time as MWNT content increase, which is related to increment of electric conductivity of the film. Through this study, it may able to contribute to process simplification, reducing process cost, and suggesting a solution to disadvantage of rubbing process.

• Science of Emotion and Sensibility
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• v.26 no.2
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• pp.129-140
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• 2023

Following ISO 20471, in this study, first, two sets of safety clothes and safety vests were made by designing and attaching animal and bird patterns preferred by children to retroreflective films and black fabrics on those fluorescent fabrics and retroreflective materials prescribed by international standards. Second, by mounting a smart photonic device on the safety clothing so that the body can be recognized from a distance even without an ambient light source at night, children can emit three types of light depending on the situation with just one-touch of the button. From a result of comparison with visibility a day and night by dressing a mannequin in the made smart safety clothing, the difference in visibility was evident at night, it was confirmed that we can see the figure of a person even at a distance of approximately 70 m. Therefore, it is expected to contribute to the prevention of traffic and other accidents on the road, as the drivers driving at night or in bad weather can recognize a person from a distance. Third, in case of the energy is exhausted and cannot maintain the stability of the light-emitting function of the optical faber, we can use energy harvesting device, and the light-emitting time will be extended. As a result it comes up to emit light stably for a long time. And this prove that smart photonic safety clothing can also be used for night workers. Therefore, optical fiber safety clothing is expected to be highly wearable not only in real life but also in dark industrial sites due to stable charging by applying the energy harvesting provided by solar cells.

• Land and Housing Review
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• v.14 no.3
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• pp.93-106
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• 2023

This study attempted to simulate changes in the thermal environment according to the type of apartment complex in Korea using CFD techniques and evaluate the thermal environment by type of apartment. First, apartment complex types in the 2000s and 2010s were referred from previous studies and four types of apartment complex were extracted from. Second, the layout of the apartment complex and temperature changes were analyzed by the direction of wind inflow. Third, a standardized model was created from each type using tower type, plate type, and mixed driving. Last, CFD simulations were performed by setting up the inflow of wind from a total of eight directions. The temperature was relatively low in the type consisting of only the tower type and the type of placing the tower type in the center of the complex, regardless of the direction of the wind. It was due to the good inflow of wind from these types to the inside of the complex. It can be interpreted because wind flows easily into the complex in these types. The findings showed that wind flow and resulting temperature distribution patterns differed depending on the building type and complex layout type, confirming the need for careful consideration of the complex layout in the early design stage. The results are expected to be used as basic data for creating a sustainable residential environment in the early design stage of apartment complexes in the future.

• Journal of Popular Narrative
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• v.25 no.4
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• pp.9-43
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• 2019

Web novels are one of the most actively adapted genre novels under a new medium called the Internet. Research on cultural content implemented on top of digital media is naturally closely related to environmental changes in digital media. The same goes for Web novels sparked by the identity of Web platforms. Especially in the case of web novels, the platform itself that provides them has triggered direct changes in genre code and reading patterns. From this perspective, this thesis wanted to examine the formation process and strategic features of web novels, which became content and products on the web platform environment. First of all, through the formation process ranging from communication novels to Internet novels and web novels, I arranged the transition to digital media and the change of genre novel market. This was an attempt to extract that Web novels not only have continuity as genre novels, but also have a turning point as digital content. Web novels are digital content that internalizes the values of the Web 2.0 era. It should also be a core product that grows the pie in the market in its own right. This paper noted that web novels are content that embodies these consumption values. So this thesis considered about what is the visualization and commercialization strategy of the web-based novels that is currently formed, and what is the current status of the web-based romance novels as the content and the product that is driving OSMU most actively in the process of commercialization. Through this process, I found that the greatest characteristic of web novels as genre novels that have evolved into digital content is their division and crack of genre.

• Korean Journal of Culture and Social Issue
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• v.8 no.1
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• pp.41-59
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• 2002

The present study explored the major behavior patterns of drivers and the environmental settings having an effect on traffic accident using the data collected from drivers and traffic police. Drivers and traffic police read questionnaire which contain the passible causes of traffic accident and selected the major causes on the basis of their latest accidents. Unexperienced drivers were forced to answer the questionnaire by referring to their friends and neighborhoods. The results showed that the major causes of traffic accident were connected with the driver's factors. The most important cause of traffic accidents was inattention/incautiousness. The next were lack of competence, skill, and experience. One interesting fact was that drivers and traffic police attributed differently. Drivers pointed out the lack of ability coping with an emergency and the insufficient skill of defensive driving as causes of the traffic accident. On the other hand, traffic polices indicated the intentional violations such as the disregard for traffic rules, trespassing on the central line of the roadway, speed limit violation, and breaking into the vehicle's line. The implications for appling the this results to driver education institutions were discussed.

• Journal of Korean Orthopaedic Sports Medicine
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• v.11 no.1
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• pp.51-56
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• 2012

Purpose: Golf is a popular sports activity after total knee arthroplasty in old age patients. We evaluated golf and implant loosening through the radiologic method. We also evaluated correlation of patterns of golf activity and clinical outcome to suggest guidelines to the patients. Materials and Methods: We carried out a retrospective case-control study of 80 patients (80 knees) who underwent TKR between 2005 and 2008, and followed up more than 3 years. We divided patients who played golf after TKR as a study group and who did not participate sports activities as a control group. We calculated the sum of width of radiolucent line in 7 sections around femoral component, 7 sections around tibial components and 5 sections in patella component using American Knee Society Roentgenographic Evaluation and Scoring system respectively. The inclusion criteria, was BMI (body mass index) was between 25 and $30kg/m^2$, and UCLA activity-level rating System score was between 5 and 8. We also got the information of patients' patterns of golf activities such as 1. the interval from surgery to return to golf activity. 2. the frequency of golf activities 3. using spike or cart. We obtained the information from patient's questionnaire and telephone interview. We compared with the VAS (visual analogue scale) respectively. And handicaps and driving distance was evaluated as well. Results: The study group's mean sum of radiologic score was 0.84 mm and 0.69 mm in control group. This is not statistically significant (p=0.22). Too early returning to golf (p=0.01) and left knee replacement (p<0.01) were statistically significant factors affecting clinical outcomes of golf activities after total knee arthroplasty. Conclusion: We concluded that golf activities after total knee arthroplasty is not correlated with radiographic loosening, and we need to give an explanation to the patients about increased pain when returing to golf too early and left side arthroplasties.