Ulsan City Research Articles

A Study on the Operation Status, Service Providers' Perceptions, and Users' Parents Satisfaction of Lifelong Education Centers for Individuals with Developmental Disabilities: Focusing on the First Established Institution in Ulsan City

A Study on the Operation Status, Service Providers' Perceptions, and Users' Parents Satisfaction of Lifelong Education Centers for Individuals with Developmental Disabilities: Focusing on the First Established Institution in Ulsan City

Use of Big Data to Evaluate Adverse Ophthalmic Adverse Events after COVID-19 Vaccination

Purpose: This study explored the types and incidences of adverse ophthalmic adverse events after COVID-19 vaccination and their associations with such vaccination in patients who presented to the sole local, tertiary, general hospital in region Ulsan of South Korea complaining of ophthalmic discomfort after COVID-19 vaccination.Methods: This cross-sectional study was conducted at Ulsan University Hospital, which is the only tertiary general hospital in Ulsan city. All participants visited the hospital from March 2021 to August 2022 complaining of ophthalmic discomfort after COVID-19 vaccination. Clinical variables were collected from both our clinical data warehouse and the electronic medical records of the hospital.Results: To date, 2,766,569 COVID-19 vaccine doses have been administered in Ulsan city. A total of 97 cases of vaccination-related adverse ophthalmic events have been confirmed. In 21 of these cases, irreversible sequelae persisted after the side-effects. Most symptoms developed within 1 week after vaccination (mean 5.06 ± 6.86 days). The most common symptom was visual disturbance (67 cases), followed by ocular pain (19 cases) and double vision (16 cases). The most frequent diagnoses associated with irreversible sequelae were neurological diseases (7 cases), retinal diseases (5 cases), and glaucoma (5 cases). The frequencies of side effects were highest for those of BNT162b2 status (34 cases), followed by those of ChAdOx1 (30), mRNA-1273 (20), and Ad26.COV2.S (4).Conclusions: In contrast to other vaccinations, COVID-19 vaccination was viewed as urgent; a few known ophthalmic side effects developed after vaccination. Although such adverse events are rare, affected patients must be closely monitored; the sequelae may be irreversible.

A newly application of Organic Rankine Cycle for building energy management with cooling heating power hydrogen liquefaction generation- South Korea

This research revolves around the modeling and optimization of an innovative geothermal system powered by geothermal energy. The system incorporates a modified Organic Rankine Cycle to efficiently produce electricity, hydrogen, cooling, and heating. The study is specifically tailored for South Korea, with a focus on the city of Ulsan. The primary objective of this geothermal system is to generate essential products for residential buildings without contributing to carbon emissions or environmental pollution. The modeling aspect of this research is conducted using EES software, while optimization efforts are aimed at enhancing performance by optimizing the exergy efficiency and reducing costs. The response surface method (RSM) and Design Expert optimization software are employed for this purpose. The optimal results demonstrate that, in its most efficient state, the system can achieve an impressive exergy efficiency of 45.382 % and operate at a cost rate of 50.414 $/h. The economic analysis underscores that the modified ORC unit bears the highest system cost, amounting to 49.47 $/h. The findings reveal that the suggested geothermal system performs exceptionally well in cities with weather conditions akin to Ulsan. In other regions across the globe, it has the potential to significantly enhance cost-effectiveness and exergy efficiency. The research concludes by evaluating the system's capacity to provide electricity, heating, and cooling for residential complexes within the study areas, highlighting its potential for addressing diverse energy needs in urban settings while prioritizing sustainability and environmental responsibility. The results showed that the study system can produce 3,982,413.6 kWh of heating, and 4,555,440 kWh of cooling during the year. The environmental results showed that by producing 4088.72 MWh of electricity annually in the city of Ulsan, South Korea, it is possible to help the expansion of 4 hectares of green space per year. Also, by reducing carbon dioxide emission by 834.09 tons of CO2, the proposed system avoids the cost of 20,018.3 $ on the environment. The proposed geothermal system can supply the electrical needs of 401 people in Ulsan city during the year.

Design and Experiment of Satellite-Terrestrial Integrated Gateway with Dynamic Traffic Steering Capabilities for Maritime Communication.

This study presents the architectural design and implementation of a multi-RAT gateway (MRGW) supporting dual satellite and terrestrial connectivity that enables moving maritime vessels, such as autonomous surface ships, to be connected to multiple radio access networks in the maritime communication environment. We developed an MRGW combining LTE and very-small-aperture terminal (VSAT) access networks to realize access traffic steering, switching, and splitting functionalities between them. In addition, we developed communication interfaces between the MRGW and end-devices connecting to their corresponding radio access networks, as well as between the MRGW and the digital bridge system of an autonomous surface ship, enabling the MRGW to collect wireless channel information from each RAT end-device and provide the collected data to the digital bridge system to determine the optimal navigation route for the autonomous surface ship. Experiments on the MRGW with LTE and VSAT end-devices are conducted at sea near Ulsan city and the Kumsan satellite service center in Korea. Through validation experiments on a real maritime communication testbed, we demonstrate the feasibility of future maritime communication technologies capable of providing the minimum performance necessary for autonomous surface ships or digitized aids to navigation (A to N) systems.

A Case Study of Tidal Analysis Using Theory-Based Artificial Intelligence Techniques for Disaster Management in Taehwa River, South Korea

Monitoring tidal dynamics is imperative to disaster management because it requires a high level of precision to avert possible dangers. Good knowledge of the physical drivers of tides is vital to achieving such a precision. The Taehwa River in Ulsan City, Korea experiences tidal currents in the estuary that drains into the East Sea. The contribution of wind to tide prediction is evaluated by comparing tidal predictions using harmonic analysis and three deep learning models. Harmonic analysis is conducted on hourly water level data from 2010–2021 using the commercial pytides toolbox to generate constituents and predict tidal elevations. Three deep learning models of long short-term memory (LSTM), gated recurrent unit (GRU), and bi-directional lstm (BiLSTM) are fitted to the water level and wind speed to evaluate wind and no-wind scenarios. Results show that Taehwa tides are categorized as semidiurnal tides based on a computed form ratio of 0.2714 in a 24-h tidal cycle. The highest tidal range of 0.60 m is recorded on full moon spring tide indicating the significant lunar pull. Wind effect improved tidal prediction NSE of optimal LSTM model from 0.67 to 0.90. Knowledge of contributing effect of wind will inform flood protection measures to enhance disaster preparedness.

Risk Type Analysis of Building on Urban Flood Damage

Climate change caused by global warming has resulted in an increase in average temperature and changes in precipitation pattern and intensity. Consequently, this has led to an increase in localized heavy rain which intensifies the uncertainty of the development of urban areas. To minimize flood damage in an urban area, this study aims to analyze the flood risk effect on buildings by ranking the risk of flood damage for each building type and sorting the long-term land use plan and the building type that requires particular consideration. To evaluate the flood risk of each building type, vulnerability analysis and exposure analysis were conducted in five regions of the Ulsan City. The vulnerability analysis includes determination of each building type by using the building elements which are sensitive to flood damage. In terms of the exposure analysis, environmental factors were applied to analyze the flood depth. The mapping based on the results from two analyses provided the basis for classifying the flood risk into five classes (green, yellowish green, yellow, orange, red). The results were provided in the urban spatial form for each building type. This analysis shows that the district near the Taehwa river is the area with the highest risk class buildings (red and orange class buildings). Notably, this area plays a pivotal functional role in administrating the Ulsan City and has a high density of buildings. This phenomenon is explained by city development which is centered around the lowland; however, given the high value of property, the potential risk is proven to be high.

Awareness of Temporary Field Emergency Medical Centers Operated by Paramedics on a First-Come-First-Served Basis in a Mass Casualty Disaster

This study was conducted to identify the need for the operation of temporary field emergency medical centers (TFEMC) by paramedics on a first-come-first-served basis at disaster sites where mass casualties occurred. The survey was conducted on 119 emergency doctors and paramedics from five fire departments under the Ulsan City Fire Department. More than 77.9% of the paramedics surveyed had been dispatched for the handling of many casualties at least once, but only 31.5% of them had experienced the establishment and operation of TFEMC. Awareness of triage showed a significant difference according to work career (F = 3.455, p = .009) and assigned work (F = 3.955, p = .004). Awareness of the disaster medical response system was significantly different according to rank (F = 5.299, p = .002), work career (F = 5.575, p = .000), age (F = 3.420, p = .018), and assigned work (F = 3.114, p = .016). There was no statistically significant difference in the awareness regarding TFEMCs. Most of the paramedics answered that they had not received mass casualty-focused education and that they needed related professional education. Therefore, for the efficient operation of TFEMCs managed by paramedics on a first-come-first-served basis, it is necessary to develop and implement various related professional training courses that combine theoretical training and field practice regarding the operation of TFEMCs, thus providing many paramedics an opportunity for education.

Mobility and source apportionment of As and heavy metals in the Taehwa River sediment, South Korea: anthropogenic and seasonal effects

The river sediment is a sink for heavy metals flowed into a river from natural and anthropogenic sources. It can be a potential pollutant source in varying environmental conditions. The Taehwa River runs through Ulsan City with different geological terrains and different land uses. Hence, research on the determination of various factors affecting accumulation and mobility changes in heavy metals in the river sediment is important. The present research investigated the mineralogical compositions of the Taewha River sediment in addition to the distribution, speciation, sources, and contamination level of As and heavy metals. The sediment showed different mineralogical changes associated with flowing distance, indicating the influence of country rocks, comprising igneous rocks in the upper stream region and sedimentary rocks in the lower stream region, on mineral composition. The total concentrations of As and heavy metals in the sediment exhibited the order of Zn > Pb > Cr > Cu > Ni > As > Cd. The overall concentrations of As and heavy metals increased in the downstream region, albeit with varying degrees. According to the Environmental Protection Agency guideline for sediment pollution, including the index of pollution intensity (IPOLL) and the potential ecological risk index (RI), the sediment in the sampling stations was discovered to be polluted to varying degrees from anthropogenic activities. An abrupt increase in Pb, Zn, and Cd concentrations was observed at Station 3 in summer and fall, which was linked to the increased clay mineral content caused by seasonal and lithological changes. The sources of this increase can be attributed to a nearby industrial complex or the oxidation of sulfide minerals, which could be related to an abandoned amethyst mine. Sequential extraction studies show that potential toxicity varies for each metal. By comparison, metals such as Cr, Ni, and Cu with higher percentages in exchangeable fractions and fractions bound to carbonates can be highly toxic. The statistical analysis indicates that two groups of metals, one including Zn, Cd, and Pb and another including Cr, Ni, As, and Cu, had distinct origins.

Analyzing green space as a flooding mitigation – storm Chaba case in South Korea

A tropical storm Chaba hit the southeastern part of South Korea in 2016. Ulsan, the 8th largest city in terms of the number of population, was especially damaged with heavy flooding, and the calculated damage was approximately $500 million. By using Normalized Differences in Vegetation Index (NDVI), four districts and 46 sub-districts in Ulsan city, South Korea. Analysis results indicate that having a higher proportion of green space inside a city could have a reduction effect on flooding risks. 1 km2 of increase in green space could reduce financial insurance payment of flooding by $44,099. In addition, an increase in non- green space also could have raised insurance payment by $691,094. The result confirms that green space inside floodplain is more effective than its existence outside floodplain. The difference is about 21 times ($44,099 vs. $953,755). Green space can mitigate flooding impact to a certain degree and it could be used to determine how natural disaster policy in municipal level should be organized. In addition, it can also provide a foundation for claiming insurance payments to those facilities without careful considerations on environmental planning.

처용무의 콘텐츠 활용양상 연구

Cheoyongmu is a traditional dance representing Korea, which is based on folk tale. In addition, it was derived from the Silla period through the Goryeo Dynasty and developed and changed into royal dance during the Joseon Dynasty.Cheoyongmu has changed with each period through long history and has been admired to the present.<BR> The primary objective of this study was to determine the different personality in each historical era of Cheoyongmu. It is necessary to examine and analyze the chronological situation. In addition, this study examines its value as content and the cultural archetypes inherent in Cheoyongmu to ensure proper transmission. Analyzing the Cheoyong Culture Festival and regular performances, Cheoyong, of the National Gugak Center in 2019 were the method of this study.<BR> The analysis of the changes in the era of Cheoyongmu is divided into the stages of formation, the background of the dance, the characteristics of the dance, the form of the dance, the functional elements, the place of the dance and the recorded documents. Cheoyongmu in Silla era can be seen as the birth of Cheoyongmu, and the background of Belief of dragon and Buddhist philosophy. It was also an active dance which had the functions of entertainment and play.<BR> Cheoyong Culture Festival which is the subject of Cheoyong and regular performances, Cheoyong, of the National Gugak Center in 2019. First, the Cheoyong Culture Festival is a regional cultural festival held in Ulsan City every September through October. The 2019 Ulsan Cheoyong Culture Festival was held at Dal-dong Cultural Park in Nam-gu, Ulsan from October 18 to 20. The festival had various programs such as street performances and competitions, and many programs for citizens to participate. However, due to the large venue, there were scattered people who visited and experienced. It was regrettable that various programs were arranged at the same time and same date, so that they could not participate in various programs.<BR> It would be more convenient if the arrangement of the program, the stage for the performances for citizens to watch, and the simple paths to participate, and the signs and more personnel for an event are improved.<BR> The main reason that Cheoyongmu has been handed down to the present is that the completeness of the work and the original elements existed. Although it changed in each period based on the shamanistic function, it is though that there could be current style because the original elements did not change at all.

Analysis of the Exposure of Domestic Flight Crews to Space Radiation

The purpose of this study is to compare and analyze the exposure dose of flight crew to space radiation. Flight selection was made from Gimpo Airport to domestic destinations of Jeju Island, Busan/Gimhae, Ulsan, Yeosu, Gwangju, and Daegu city. Dose measurements were based on the CARI-6/6M model developed by the Federal Aviation Administration and the Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model, both developed by the Federal Aviation Administration. The results doses of 0.63 µSv at Jeju and 1.65 µSv at Busan/Gimhae based on the show NAIRAS model. The doses were 0.86 µSv (NAIRAS), 0.93 µSv, 1.03 µSv, 1.00 µSv fol destination of Yeosu, Ulsan, Gwangju, and Daegu, respective. Although there doses are light crews need to study appropriate safety management directions to protect themselves against space radiation, more over national standards and appropriate operational measures need to be established.

Methodology of an Analysis of Snow Disaster Risk for Establishing Climate Change Adaptation Measures

This study applies the concept of risk defined by IPCC’s fifth assessment report to Daegu City, Ulsan City, Gyeongsangbuk Province, and Gangwon Province to assess and analyze snow disaster risks. Sub-indicators of three hazards, six exposures, four vulnerabilities, and five adaptive capacities were selected, and spatial information based on grids or administrative districts was constructed. The weight of each indicator was calculated with the Analytic Hierarchy Process (AHP), and the maximum inconsistency of the expert survey result was 9.86%, indicating high consistency. The results show that administrative districts with an space average risk of “very high” are Ulleung, Gangneung, Sokcho, Yangyang, Pyeongchang, Goseong, Donghae, Samcheok, and Jeongseon, accounting for 16.7% of the entire administrative district. One region has a “high” risk, Taebaek (1.9%), and those with a “moderately high” risk were Uljin and Inje (3.8%). These regions have very high levels of hazards, very low exposure, very high vulnerability, and low adaptive capacity; hence, hazard, vulnerability, and adaptive capacity had a significant effect on the increased risk. Pyeongchang had the highest standard deviation of gridded risk among the 12 regions with a risk above moderately high. The standard deviation of gridded risk for Pyeongchang was estimated to be 1.0 with the highest value, followed by Inje, with 0.69, and Jeongseon, with 0.55; therefore, differentiated climate change adaptation measures should be established according to gridded risks.

태풍 차바(CHABA)로 인한 지방정부와 주민간의 갈등사례의 정책적 함의 -울산 중구 피해사례를 중심으로-

태풍 차바(CHABA)로 인한 지방정부와 주민간의 갈등사례의 정책적 함의 -울산 중구 피해사례를 중심으로-

Molecular Detection and Phylogenetic Analysis of Anaplasma spp. in Korean Native Goats from Ulsan Metropolitan City, Korea.

Background: Tick-borne diseases (TBDs) can be fatal to humans as well as to animals causing severe economic losses globally to livestock industries. Many countries conduct regular surveillance of TBDs in livestock. Serological and molecular surveillance of TBDs in livestock and humans was carried out in the Republic of Korea. However, there are not a lot of data on analyses of anaplasmosis in Korean native goats and the correlation with rearing methods and seasons. Methods: In this study, goats in Ulsan city were tested for anaplasmosis by PCR and 16S rRNA sequencing. A total of 452 goat blood samples were collected from 20 farms in 2016. The goat farms in Ulsan city had three different types of rearing methods: conventional, confined, and mixed grazing-confined. Results: Forty-nine of the 452 goats (10.8%) were anaplasmosis positive. Sequence analysis of the PCR products from these 49 goats revealed that 39 of 452 goats (8.6%) were Anaplasma bovis positive, and 10 of 452 goats (2.2%) were infected with Anaplasma capra. The highest outbreaks of anaplasmosis occurred in mixed grazing-confined type of farms (27.1%, 33/122) (χ2 = 60.72, df = 2, p < 0.05), but there was no significant difference in the occurrence of anaplasmosis between spring, summer, and fall seasons. Conclusions: This study was the first detection of A. bovis in Korean native goats and its relationship with rearing methods and seasons. These findings suggested that Korean native goats were highly exposed to Anaplasma spp. during summers when the tick population is the highest and in farms employing mixed grazing-confined rearing methods.

A Study on the Distribution Characteristics of Invasive Alien Plants in Ulsan City, South Korea

A Study on the Distribution Characteristics of Invasive Alien Plants in Ulsan City, South Korea

박정희 정권 초기 공업센타 울산의 건설계획과 추진

박정희 정권 초기 공업센타 울산의 건설계획과 추진

Emergency Evacuation Plan for Hazardous Chemicals Leakage Accidents Using GIS-based Risk Analysis Techniques in South Korea.

Despite improvements in chemical safety management systems, incidents involving the release of hazardous chemicals continue to happen. In some cases, they result in the evacuation of residents. For hazardous chemical release accidents, an evacuation plan needs to be selective enough to consider both the indoor and outdoor concentrations of nearby buildings and the time in which the maximum allowable concentration may occur. In this study, a real-time risk analysis tool was developed based on the geographic information system (GIS) in order to establish the emergency response and risk communication plan for effectively assisting decision-making personnel. A selective evacuation plan was also established by a proposed assessment module considering the indoor/outdoor pollution concentration of buildings and the release duration time of chlorine gas leakage. The GIS-based simulated modules were performed based on eleven buildings of Ulsan city, located near an industrial cluster and home to a high population density. As a result of the simulated real-time risk assessment, only four buildings were affected by chlorine gas concentration according to wind direction and diffusion time. In addition, it was considered effective to establish an indoor/outdoor evacuation plan as opposed to an outdoor evacuation plan which is outside the range of the damage. Subsequently, an emergency evacuation plan was established with the concentration of a hazardous chemical according to the decision-making matrix. This study can enlighten the real-time emergency risk assessment based on GIS while effectively supporting the emergency action plans in response to the release of hazardous chemicals in clustered plants and the community.

Investigating Influence of Hydrological Regime on Organic Matters Characteristic in a Korean Watershed

Source tracking of dissolved organic matter (DOM) is important to manage water quality in rivers. However, it is difficult to find the source of this DOM because various DOMs can be added from the river watershed. Moreover, the DOM composition can be changed due to environmental conditions. This study investigated the change of organic matter characteristics in the Taewha River of Ulsan City, Korea, before and after rainfall. A Soil and Water Assessment Tool (SWAT) was used to simulate water flow from various sources, and dissolved organic matter characterization was conducted in terms of molecular size distribution, hydrophobicity, fluorescence excitation and emission, and molecular composition. From the results, it was found that lateral flow transported hydrophobic and large-molecule organic matter after rainfall. According to the orbitrap mass spectrometer analysis, the major molecular compound of the DOM was lignin. Coupling the SWAT model with organic matter characterization was an effective approach to find sources of DOM in river.

The effect of diabetes on 4-year changes of hearing thresholds in male workers exposed to noise in a single company: a longitudinal study.

BackgroundRecently, several studies have assessed the association between diabetes and hearing impairment. However, the effect of diabetes on hearing impairment is not well known in diabetic patients exposed to noise, a typical cause of hearing impairment. The aim of this study is to longitudinally analyze the effect of diabetes on hearing impairment in workers exposed to similar noise levels from 2013 to 2017 who had experienced little change in their working conditions.MethodsThe study subjects included 2,087 male workers exposed to noise in a single company and who underwent health examinations at the same hospital in Ulsan city in 2013 and 2017. Hearing impairment was defined that a pure-tone average of pure-tone audiometry (PTA) thresholds at 1,000, 2,000, 3,000, and 4,000 Hz was 25 dB and over in both ears. Statistical analyses were conducted using χ2 tests, ANOVA, and Cox proportional hazard models. We analyzed covariates that might affect hearing impairment, including age; working period; levels of total cholesterol, triglyceride, and serum creatinine; smoking and alcohol history; and noise level.ResultsThe average PTA thresholds and their average changes between 2013 and 2017 were significant in the diabetes mellitus (DM) group than those in the normal and impaired fasting glucose group. Among the subjects with the same status of fasting glucose group in 2013 and 2017, the adjusted hazard ratios for incident hearing impairment among those in the DM group compared to normal group were 3.35 (95% confidence interval [CI], 1.54–7.29) in the left ear and 5.66 (95% CI, 2.01–15.98) in the right ear.ConclusionsThis study suggested that the risk of hearing impairment in the DM group was significantly higher than that in the normal group in both ears, even when exposed to similar noise levels.

Source and remediation for heavy metals of soils at an iron mine of Ulsan City, Korea

Ulsan mine produced the iron ore minerals of magnetite, arsenopyrite, and scheelite in 1992, and serpentine was developed from 1977 to 2002. The soils of the mine were contaminated by heavy metals such as As, Zn, Ni, and Cd. Heavy metals of Ni and Zn came mostly from serpentinite, and As was derived mainly from arsenopyrite in the scan-type iron ore body. As, Zn, and Ni were major contaminants, but Cd was a minor contaminant on a basis of Korean standard. The heavy metals in the deep depth (> 5 m) came from the host rocks, and those in the shallow depth (< 5 m) were derived from the organic–mineral complexation soil. The remediation plan was a soil washing for highly contaminated soils and the containment of clay materials for less contaminated soils. Even though the remediation methods were successful, the continuous monitoring and the analysis of monitoring data are still necessary for the conservation of soil and groundwater around the study area.