• Journal of Information Processing Systems
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• 제14권6호
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• pp.1445-1456
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• 2018

Environment perception and three-dimensional (3D) reconstruction tasks are used to provide unmanned ground vehicle (UGV) with driving awareness interfaces. The speed of obstacle segmentation and surrounding terrain reconstruction crucially influences decision making in UGVs. To increase the processing speed of environment information analysis, we develop a CPU-GPU hybrid system of automatic environment perception and 3D terrain reconstruction based on the integration of multiple sensors. The system consists of three functional modules, namely, multi-sensor data collection and pre-processing, environment perception, and 3D reconstruction. To integrate individual datasets collected from different sensors, the pre-processing function registers the sensed LiDAR (light detection and ranging) point clouds, video sequences, and motion information into a global terrain model after filtering redundant and noise data according to the redundancy removal principle. In the environment perception module, the registered discrete points are clustered into ground surface and individual objects by using a ground segmentation method and a connected component labeling algorithm. The estimated ground surface and non-ground objects indicate the terrain to be traversed and obstacles in the environment, thus creating driving awareness. The 3D reconstruction module calibrates the projection matrix between the mounted LiDAR and cameras to map the local point clouds onto the captured video images. Texture meshes and color particle models are used to reconstruct the ground surface and objects of the 3D terrain model, respectively. To accelerate the proposed system, we apply the GPU parallel computation method to implement the applied computer graphics and image processing algorithms in parallel.

• 대한치과기공학회지
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• 제22권1호
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• pp.113-128
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• 2000

The purpose of this study was to serve as a basis for the development of dental technology and for creating a condition that dental technicians could work with pride and right values, by examining what problems there were in their health care, what they thought about them, and how the problems could be solved, The findings of this study were as below: 1. The most serious and harmful element in dental technology workshop was a dust(57.5%) and a noise(33.3%). 2. Approximately 99.0% of the dental technicians investigated made a complain of air pollution caused by noise. Their opinion on a possible measure to remove noise air pollution was that the noise-generating machine should be replaced(64.1%) or that it should be isolated(28.8%). 3. 76.0% complained air pollution cause by dust deteriorates their working efficiency. As a way to eliminate it, they suggested a dust chamber(35.3%) or an air cleaner(27.5%) should be installde. 4. About 80% made a complain of gas air pollution. The most common related symptom was a headache(56.9%). They thought that gas-generating machine should be isolated(39.9%) or that an air purifier should be prepared(33.3%). 5. The largest impact of heat and light on their body was weakening their eyesight(56.9%). 47.1% got burn once though four times, and 34.3% did five times or more. The way to prevent them was to install an automatic casting machine(66.0%) or use protective glasses(28.1%). 6. Approximately 47.7% were considering a change of occupation, and the most common reason was heavy work(23.5%), followed by poor prospect(21.6%) and working environment(19.0%) in the order named. 7. 88.9% responded they were likely to have an occupational disease. Their idea about the proper frequency of regular health examination was once a year(53.6%), or once per every six months(41.8%). 8. The field they were most interested in was health care(39.2%), followed by academic research activities(31.4%). This fact indicated it's most urgently required to improve their working environment.

• Safety and Health at Work
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• 제8권4호
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• pp.364-370
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• 2017

Background: Labeled noise reduction (NR) data presented by manufacturers are considered one of the main challenging issues for occupational experts in employing hearing protection devices (HPDs). This study aimed to determine the actual NR data of typical HPDs using the objective fit testing method with a microphone in real ear (MIRE) method. Methods: Five available commercially earmuff protectors were investigated in 30 workers exposed to reference noise source according to the standard method, ISO 11904-1. Personal attenuation rating (PAR) of the earmuffs was measured based on the MIRE method using a noise dosimeter (SVANTEK, model SV102). Results: The results showed that means of PAR of the earmuffs are from 49% to 86% of the nominal NR rating. The PAR values of earmuffs when a typical eyewear was worn differed statistically (p < 0.05). It is revealed that a typical safety eyewear can reduce the mean of the PAR value by approximately 2.5 dB. The results also showed that measurements based on the MIRE method resulted in low variability. The variability in NR values between individuals, within individuals, and within earmuffs was not the statistically significant (p > 0.05). Conclusion: This study could provide local individual fit data. Ergonomic aspects of the earmuffs and different levels of users experience and awareness can be considered the main factors affecting individual fitting compared with the laboratory condition for acquiring the labeled NR data. Based on the obtained fit testing results, the field application of MIRE can be employed for complementary studies in real workstations while workers perform their regular work duties.

• 유통과학연구
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• 제17권12호
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• pp.23-32
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• 2019

Purpose As consumer awareness grows, the importance of CSR becomes even more important for long-term growth. In response to this current trend, the purpose of this study is to analyze the effect of CSR activities on business performance for logistics companies. Research design, data, and methodology - Between CSR activities and growth, there was a generally positive(+) relationships between activities such as donation and volunteerism and the growth of the enterprise. In terms of the relationship between environmental factors and growth, negative results were expressed. In case of profitability, improved welfare for workers has had a positive impact on corporate profitability. Results - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community. Conclusions - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community.

• 한국환경생태학회지
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• 제36권3호
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• pp.350-357
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• 2022

본 연구에서는 국립공원에서 자연의 소리는 생태계의 구성요소임과 동시에 탐방객들이 공원을 체험하는 중요한 요소이다. 따라서 국립공원 내 소음 분포 특성을 파악하고 자연의 음환경(Soundscape) 보존 및 복원을 위한 노력은 국립공원 관리 차원에서 중요한 과제 중 하나이다. 그러나 여전히 국내 국립공원에서는 소음 관리 및 음환경 보존에 대한 관심이 미약한 것이 사실이다. 무등산국립공원은 호남지역에서 가장 중요한 자연보호지역 중 하나로 계절별 동물이 우는 소리, 물소리, 바람 소리 등 탐방객들에게 자연의 소리를 제공할 수 있는 최적의 장소이지만 대도시에 인접해 있고 공원 내부로 도로 및 대규모 시설지가 인접해있는 등 소음이 발생하여 공원 내 음환경에 위협이 되고 있는 상황이다. 따라서 본 연구는 소음지도, 탐방로 소리등급도, 주요 지점의 음환경 녹음 데이터, 소리자원 분포도 등의 분석을 통해 무등산국립공원 내 소리 분포 특성을 파악하고 광범위한 소음의 영향을 나타냄으로써 음환경 관리의 필요성을 시사하고 있다는 중요성을 지니고 있다. 반면 본 연구에서는 연구 인력과 장비의 한계로 인하여 소음지도, 탐방로 소리등급도, 소리자원 분포도의 속성 데이터 수집 기간이 상이한 점이 한계점으로 남는다. 그러나 본 연구의 결과는 탐방 만족도 및 자연의 음환경 보존 등을 목표로 향후 지속적인 음환경 보존 및 관리를 위해 활용될 수 있는 기초자료가 될 것으로 판단된다.

• Elastomers and Composites
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• 제52권4호
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• pp.249-256
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• 2017

The history of polyurethane is relatively shorter compared to that of the other polymers, though its importance has grown rapidly. Due to its unique properties, polyurethanes are widely applied in various fields. In particular, the automotive industry is one of the important application fields. To date, polyols and isocyanates used in the polyurethane industry are generally of petrochemical origin. Recently, owing to the oil crisis, legislation, and growing awareness towards environmental preservation, the demand for more sustainable and eco-friendly raw materials has increased. In this paper, the latest research and development trends in polyurethane applications were reviewed, with a focus on the automobile industry in areas such as seat comfort, noise reduction, light weight, biomass-based polyurethane, and recycling.

• Wind and Structures
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• 제30권5호
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• pp.511-524
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• 2020

Advancements in materialistic life styles and increasing awareness about adverse climatic changes and its negative effects on human life have been the driving force of finding new and clean sources of energy. Wind power has become technologically mature and commercially acceptable on global scale. However, fossil fuels have been the major sources of energy in most countries, renewable energy (particularly wind) is now booming worldwide. To cope with this wind energy technology, various related aspects have to be understood by the scientific, engineering, utility, and contracting communities. This study is an effort towards the understanding of the (i) wind turbine blade and tower structural stability issues, (ii) turbine blade and tower failures and remedial measures, (iii) weather and seismic effects on turbine blade and tower failures, (iv) gear box failures, and (v) turbine blade and tower failure analysis tools.

• Journal of Korean Biological Nursing Science
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• 제25권1호
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• pp.55-62
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• 2023

Purpose: Tinnitus, which is often described as the conscious awareness of a sound without an external auditory stimulus, is one of the most common symptoms in the general population. This study aimed to explore the experiences of individuals living with tinnitus. Methods: In this qualitative exploratory study, data were collected from November 2017 to January 2018 through in-depth individual interviews with 11 tinnitus patients. Verbatim transcripts and field notes were analyzed using content analysis. Results: The extracted content was classified into three core categories of tinnitus experiences: "suffering from constant sound," "being imprisoned surrounded by persistent noise," and "efforts to overcome." Conclusion: This study shows that tinnitus had a severe negative impact on patients' lives. The finding will help healthcare providers understand their patients more deeply.

• 환경영향평가
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• 제4권1호
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• pp.25-35
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• 1995

The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factors, the study was carried out through theoretical research and a survey of public awareness as a ways to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment: to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the following were identified as preferential assessment factors in the settlement and surrounding areas cultivation marine products, change of temperature of seawater due to flow of warm water, land use(negative), noise vibration during construction, existing plants, erosion accumulation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both settlement area and neighboring areas. In the settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.

• 환경영향평가
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• 제4권3호
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• pp.15-26
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• 1995

The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factor, the study was carried out through theoretical research and a survey of public awareness as way to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment : to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the followings were identified as preferential assessment factors in the displacing settlement and surrounding areas: cultivation marine products, change of temperature of seawater due to flow of warm water, land use (negative), noise vibration during construction, existing vegetations, erosion sedimentation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both displacing area and neighboring areas. In the displacing settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.