• Journal of the Korean Society of Safety
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• v.34 no.3
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• pp.57-64
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• 2019

Lack of incident reporting culture has been pointed out as a potential risk factor across industries. Consequently, comprehensive understanding of the factors affecting the willingness to report (WTR) is necessary. However, our knowledge on the related studies are not enough to date and even most parts of the existing studies have focused on patient safety, which makes it difficult to universally apply the factors to all industries. Therefore, this study aimed to identify WTR factors in chemical plants and evaluate the influence degree of the factors. To do this, 45 candidate factors were summarized throughout the previous studies and surveying plant safety staff. A questionnaire survey was conducted for 614 all employees from 9 chemical plants which belong to one company, and finally 32 WTR factors were identified throughout 520 responses. Of these, 19 factors were consistent with the previous studies and 13 factors were newly identified. The most influential factor was 'Views on the necessity of incident reporting', and 'Reporting practice by outcome severity', 'Fear of vilification, conflicts, blame, or sanctions' were followed. This result not only suggests various WTR factors suitable for chemical plants, but also shows need to derive specific factors that are appropriate to each industry. An empirical study could be expected to increase incident reporting by using these factors and verify its effectiveness on injury rate.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.2
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• pp.107-111
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• 2014

An SIW cavity is a useful tool to design an FSS which shows a rapid roll-off rate and insensitivity to polarizations and incident angles of electromagnetic waves. However, due to its high Q-factor, the FSS also shows narrow bandwidth which is undesirable for high-capacity communication. To address this drawback, we propose a novel technique to enhance the bandwidth while maintaining similar frequency response characteristics and minimizing the increase of the overall thickness of the SIW cavity FSS. In order to verify the performance of the technique, simulated frequency responses will be provided. Also, a parameter which affects the bandwidth will be studied. Finally the stability to polarizations and incident angles will be observed through the simulated results.

• Journal of the Korean Society of Safety
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• v.19 no.2
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• pp.34-40
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• 2004

This paper presents an analysis of SAR(Specific Absorption Rate) distribution characteristics in a head model using FDTD(Finite Difference Time Domain). In this study human head was modelled in four elements-layered structure, consisting of skin, fat, skull and brain. To calculate the electromagnetic fields wihtin the head model, FDTD method was used. In the FDTD method, the electromagnetic wave is analyzed by solving a Maxwell's equations repeatedly. For the calculation, distance between power source and head model increased by 10[m]. Power density and incident electric field intensity were calculated. Based on the incident electric field, the program which calaculated internal electric fields intensity and SAR calculation of the head model were developed. The results of developed program using FDTD were compared with those of a commericial programs, which showed the availability and usefulness of the suggested scheme in this paper.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6089-6097
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• 2012

This study suggested a method of detecting an incident inside tunnel by using camera that is installed within the tunnel. As for the proposed incident detection method, a static object, travel except vehicles, smoke, and contra-flow were detected by extracting the moving object through using the real-time background image differencing after receiving image from the camera, which is installed inside the tunnel. To detect the moving object within the tunnel, the positive background image was created by using the moving information of the object. The incident detection method was developed, which is strong in a change of lighting that occurs within the tunnel, and in influence of the external lighting that occurs in the entrance and exit of the tunnel. To examine the efficiency of the suggested method, the experimental images were acquired from Marae tunnel and Expo tunnel in Yeosu of Jeonnam and from Unam tunnel in Imsil of Jeonbuk. Number of images, which were used in experiment, included 20 cases for static object, 20 cases for travel except vehicles, 4 cases for smoke, and 10 cases for contra-flow. As for the detection rate, all of the static object, the travel except vehicles, and the contra-flow were detected in the experimental image. In case of smoke, 3 cases were detected. Thus, excellent performance could be confirmed. The proposed method is now under operation in Marae tunnel and Expo tunnel in Yeosu of Jeonnam and in Unam tunnel in Imsil of Jeonbuk. To examine accurate efficiency, the evaluation of performance is considered to be likely to be needed after acquiring the incident videos, which actually occur within tunnel.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.7
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• pp.106-115
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• 2002

Growth characteristics of micro carbon structures fabricated by laser-assisted chemical vapor deposition are studied. Argon ion laser and ethylene were used as the energy source and reaction gas, respectively, to grow micro carbon rod through pyrolytic decomposition of the reaction gas. Experiments were performed at various conditions to investigate the influence of process parameters on growth characteristics such as the diameter or growth rate of the micro carbon rod with respect to reaction gas pressure and incident laser power. Reaction gas pressure in experiments ranges from 200 to 600Torr and the incident laser power from 0.3 to 3.8W. For these conditions, the diameter of the rod increases linearly with respect to the laser power but is almost independent of the reaction gas pressure. Growth rate of the rod changes little with gas pressure when the laser power remains below IW. For a constant reaction gas pressure, the growth rate increase with Increasing laser power, but the rate of increase decreases gradually, implying that the chemical vapor deposition condition changes from a kinetically-limited regime to a mass-transport-limited regime. When the carbon rod was grown at near threshold laser power, a very smooth surface is obtained on the rod. By continuously moving the focusing lens in the direction of growth, a micro carbon rod with a diameter of 287${\mu}{\textrm}{m}$ and aspect ratio of 100 was fabricated..

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1311-1319
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• 1990

For the purpose of preventing the flow undulation in the cascade of steam turbine, the blades are made into a constant expansion rate in static pressure. And the flow in those cascades is transonic or supersonic in the range of 0.7-2.0 in Mach number. As a consequence, an oblique shock wave, known as inner or outer edge shock wave, arises in the flow of cascades. Especially when the steam in cascades is in a state of high wetness, nonequilibrium condensation and condensation shock wave occur, and they give rise to an interference with oblique shock wave. In the present study the case of expansion of moist air through a supersonic nozzle of constant expansion rate, which behaves similar to that of wet steam, was adopted. The effect of nonequilibrium condensation on the oblique shock wave generated by placing the wedge into the supersonic part of the nozzle was investigated. Furthermore, the relationship between nonequilibrium condensation zone and incident point of the oblique shock wave, oblique shock wave angle, the variations of angles of incident and reflected shock waves due to the variation of initial stagnation supersaturation and the relationship between the height of Mach stem and initial stagnation supersaturation are discussed.

• East Asian mathematical journal
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• v.39 no.5
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• pp.493-503
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• 2023

Tendency prediction of daily confirmed cases is an important issue for public health authorities. To protect the tendency, we estimate the transmission rate of stochastic SEIR model for COVID-19 in Korea using particle Markov chain Monte Carlo method. The results show that the increasing and decreasing tendency of estimated transmission rate appear one or two days in advance compared to daily incidence cases, and as time evolves the standard deviation of the estimates of transmission rate reduces. Since ten months have passed since the first incident case of COVID-19 in Korea, we expect to forecast the tendency of daily confirmed cases for the next one or two days more accurately using our method.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8345-8349
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• 2014

Background: Cancer is an increasing cause of mortality and morbidity worldwide. Incidences of common cancers has been growing in different provinces of Iran in recent years but trends in Khuzestan which shares a border with Iraq and is located in south west of Iran have not been investigated. This study aimed to assess secular changes in incidences of common cancers in Khuzestan province from 2004 to 2008. Materials and Methods: Data were collected from Khuzestan cancer registry which is a branch of Iranian Ministry of Health Cancer Registry (http://ircancer.ir) for the period 2004-2008. Data were presented as incidence rates by site, sex, age, using the crude rate and age-standardized rate (ASR) per $10^5$ persons. A direct method of standardization was applied according to the WHO guideline and data analysis was performed using the SPSS package. Results: During the 2004-2008 period, 14,893 new cases of cancer were registered in Khuzestan cancer registry. The age-standardized incidence rate of all cancers was 153.7 per $10^5$ in males and 156.4 per $10^5$ in females. The incidence was increased over the period of five years. The most incident cancers among males were skin cancer ($ASR=18.7/10^5$), stomach cancer ($ASR13.8/10^5$), lung cancer ($ASR12.9/10^5$), leukemia ($ASR=12.6/10^5$) and prostate cancer ($ASR=12.4/10^5$). In females, the most incident cancers were breast cancer ($ASR=41/10^5$), skin cancer ($ASR=16.4/10^5$), colorectal cancer ($ASR=10.0/10^5$), leukemia ($ASR=8.1/10^5$) and lung cancer ($ASR=6.9/10^5$). Conclusions: Incidences of various cancers are rising in Khuzestan. It is necessary to develop and implement comprehensive cancer control programs in this region which could be monitored and evaluated by the future trend data from Khuzestan cancer registry.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1953-1958
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• 2015

Background: In India, cancer accounts for 7.3% of DALY's, 14.3% of mortality with an age-standardized incident rate of 92.4/100,000 in men and 97.4/100,000 in women and yet there are no nationwide screening programs. Materials and Methods: We calculated age-standardized and age-truncated (30-69 years) detection rates for men and women who attended the Indian Cancer Society detection centre, New Delhi from 2011-12. All participants were registered with socio-demographic, medical, family and risk factors history questionnaires, administered clinical examinations to screen for breast, oral, gynecological and other cancers through a comprehensive physical examination and complete blood count. Patients with an abnormal clinical exam or blood result were referred to collaborating institutes for further investigations and follow-up. Results: A total of n=3503 were screened during 2011-12 (47.8% men, 51.6% women and 0.6% children <15 years) with a mean age of 47.8 yrs (${\pm}15.1yrs$); 80.5% were aged 30-69 years and 77.1% had at least a secondary education. Tobacco use was reported by 15.8%, alcohol consumption by 11.9% and family history of cancer by 9.9% of participants. Follow-up of suspicious cases yielded 45 incident cancers (51.1% in men, 48.9% in women), consisting of 55.5% head and neck (72.0% oral), 28.9% breast, 6.7% gynecological and 8.9% other cancer sites. The age-standardized detection rate for all cancer sites was 340.8/100,000 men and 329.8/100,000 women. Conclusions: Cancer screening centres are an effective means of attracting high-risk persons in low-resource settings. Opportunistic screening is one feasible pathway to address the rising cancer burden in urban India through early detection.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.46-54
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• 2007

The purpose of this study was to examines the burning rate of fire retardant treated wood in the cone heater with a one-dimensional integral model. The wood samples used in this study were four species. The species of woods are Redwood, White oak, Douglas fir and Maple. Each sample was nominally 50mm thick and 100mm square. Samples were exposed to a range of incident heat fluxes 10 to $35kW/m^2$ using the cone heater. A one-dimension integral model has been used to predict burning rate, heat of gasification, flame heat fluxes, charring rate and char depth of samples. As a result measurement of mass loss rate, softwoods(Redwood and Douglas fir) has relatively low value than those for hardwoods(White oak and Maple). Average charring rate of woods in case of fire retardant treatment showed reduction effect of 41.29%, 50.00%, 48.18% and 60.82% for Redwood, Douglas fir, White fir and Maple, respectively. Almost all the predictions from integral model showed faster charring than those measured. Average difference between predictions and experimental data was 16%, 9.5% and 11.8% for N, F1 and F2 respectively. Water-soluble fire retardant used in this study find out more effect in hardwood than softwood from the result of measurement of mass loss rate and average charring rate.