• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1085-1098
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• 2014

Plastic mechanism analysis of structures subjected to large deformation has long been used in order to determine collapse mechanisms of steel structures, and the energy absorbed in plastic deformation during such collapses. In this paper the technique is applied to vehicle roof structures that undergo large plastic deformation as a result of rollover crashes. The components of such roof structures are typically steel spot-welded hat-type sections. Ten different deformation mechanisms are defined from investigations of real-world rollover crashes, and an analytical technique to determine the plastic collapse load and energy absorption of such mechanisms is determined. The procedure is presented in a generic manner, such that it may be applied to any vehicle structure undergoing a rollover induced collapse. The procedure is applied to an exemplar vehicle, in order to demonstrate its application in determining the energy absorbed in the deformation of the identified collapse mechanisms. The procedure will be useful to forensic crash reconstructionists, in order to accurately determine the initial travel velocity of a vehicle that has undergone a rollover and for which the post-crash vehicle deformation is known. It may also be used to perform analytical studies of the collapse resistance of vehicle roof structures for optimisation purposes, which is also demonstrated with an analysis of the effect of varying the geometric and material properties of the roof structure components of the exemplar vehicle.

• Journal of the Korean Society of Safety
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• v.29 no.5
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• pp.7-14
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• 2014

This study aimed to develop members with the optimum impact characteristics to ensure a protected space for passengers in the case of automobile collisions. Accordingly, these members were fabricated to provide sufficient rigidity and safety to the passenger room structure and to absorb large amounts of energy during collision. In particular, CFRP members were fabricated with different section shapes such as square and single- and double-hat shapes. Next, their impact collapse characteristics and collapse modes were quantitatively analyzed according to the changes in section shapes and stacking angles. This analysis was performed to obtain design data that can be applied in the development of optimum lightweight members for automobiles.

• Journal of the Korean Society of Marine Environment & Safety
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• v.8 no.2
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• pp.17-22
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• 2002

Die vorliegende Arbeit handelt sich uber die Risikogesellschaft und das symbolische Strafrecht. Die Risikogesellschaft bedeutet die Ggesellschaft mit kunstlich erzeugten atomaren, chemischen, okologischen und gentechnischen Selbstvernichtungsmoglichkeit. Die Risikogesellschaft hat offenbar dort, wo sie die Gefahren nicht leugnen kann, Bedurfnis nach Minimierung von Unsicherheit, Dieses Be-durfnis wirkt sich einmal aus in der Neigung, das Entstehen bestimmter nicht konsentierter Gefahren schon in einem sehr fruhen Stadium der Entwicklung mit Hilfe des Strafrechts zu stoppen. Vorverlagerung der Gefahrabwehr bedeutet im Fall des Strafrechts die Vorfeldkriminalisierung. Hierfur scheint es zwei wichtige Methoden zu geben: die Formulierung weit vorgelagerter Rechsguter und die Konstruktion vorfelderfassender Deliktstypen. Aber in die modeme Risikogesellschaft handelt sich das Strafrecht mit dem Versuch der Vorfeldkriminalisierung unubersehbare Vollzugsdefizite ein. Neben Ermittlungsschwierigkeiten sind hierfur strukturelle Zurechnungsprobleme und evidente Kontra-produktivitat verantwortlich. Es scheint dennoch einen naheliegenden Ausweg zu geben. Wo das Strafrecht in seiner instrumentellen Wirkung versage, wo ein unvermeidbares Vollzugsdefizite vorliege, komme dem Strafrecht doch eine gewichtige symbolische Bedeutung zu. Aber ein Strafrecht, das sich als Mittel zur Losung von System-problemen versteht, wirkt instrumentell zu wenig, um seine Kontraproduktivitat auszugleichen. Eben darunter leidet dann aber auch seine symbolische Wirkung, die man sich zunachst noch eine Zeitlang von ihm erhoffen mag.

• Journal of the Korean Society of Safety
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• v.38 no.5
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• pp.36-42
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• 2023

In this study, 50 ABE-type hard hats were procured from five certified commercial manufacturers, and shock absorption tests were conducted in accordance with Protective Equipment Safety Certification Notice No. 2020-35. The tests were performed under both high- and low-temperature conditions, adhering to safety helmet testing standards. The highest shock transmission ranges were recorded in the tests, with an average energy range of 2,600-4,108 N at high temperatures and 2,316-3,991 N at low temperatures. All five hard hat models demonstrated a maximum transmitted impact force below 4,450 N, without any loss of cap and attachment functionality, confirming their compliance with performance standards. Furthermore, we evaluated the side impact performance of the safety helmets of each company, with an average range of 4,722-5,267 N. Company A exhibited the lowest measurement at 4,722 N. Comparing these results with international safety standards and the national shock absorption test criteria, it was observed that the maximum transmitted shock value using government-specified impact weight falls within the range of 4,450-5,000 N. However, it was noted that developed countries have established specific standards for the side impact forces on safety helmets, which are legally mandated. Consequently, it is imperative for South Korea to enhance its safety helmet side impact performance test methodology to align with domestic standards in the future.

• Journal of the Korea Convergence Society
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• v.10 no.11
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• pp.47-53
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• 2019

Safety accidents at industrial sites can occur anytime, anywhere. Recently, research on the industrial safety management system based on the IoT has been actively conducted. However, most of the studies are studies of actions after safety accidents or simply monitoring. In this paper, the safety equipment was introduced before safety accidents occurred, and the subjects could be managed not only by workers but also by visitors. Also, it implements a system to prevent the accident by detecting the user's motion and situation periodically before a safety accident occurs. The implemented system is a system that attaches the device for safety management to the hard hat and can identify the safety situation by using the Bluetooth beacon device attached to the user's smartphone and the industrial site.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.4
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• pp.44-52
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• 2001

This study performed factor analysis for 21 independent variables related to the effect of illumination and suggested the effect by multiple regression analysis on the relationship between the effect of illumination and the satisfaction of use of a dependent variable to find the effect of illumination in urban parks at night and the effect of illumination on the satisfaction of use. The results of this study are as follows; 1) Of the 21 independent variables used to study the effect of illumination in urban parks at night, the impact on safety and possibility of crime was highly. The effects of illumination by factor analysis were abstracted as effects of removing anxiety, securing safety, increasing use. 2) As a result of multiple regression analysis, independent variables influencing satisfaction of use in urban park were proved as effects of removing anxiety, securing safety, increasing identity, preparing atmosphere and increasing use. Also, the effect of securing safety was the most important factor; it showed a level of importance 2 times higher than the effect of removing anxiety, and 7.7 times higher than the effect of preparing atmosphere in relative contribution of the effect of illumination to satisfaction of use. 3) Of the effects of illumination influencing satisfaction of use in urban parks, the effect of securing safety and the effect of increasing visibility were more significant than the effects of removing anxiety, preparing atmosphere and increasing use. This fact means that personal safety an the identity of persons or facilities in the space of use should be considered with priority in planning or designing illumination. Also, it implies hat, for night use in urban parks, lightness of the space is required for general safety of use at parks, and proper illuminance on the activity in the space of use should be required. The subject parks of this study are 8 urban neighborhood parks. The model on the effect of illumination and the satisfaction of use depends on characteristics and conditions of location of he park and user class, so the subject parks and persons should be varied, and the difference by sex or ages should be suggested.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.6
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• pp.1085-1099
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• 2016

This article is designed to establish fundamental design criterion for theme park cast costumes in accordance with play type and space. There is an understanding that theme parks act as a play space that is designed to meet diverse playing desires. To analyze cast costumes, the theme park - 'Everland' in South Korea as an example, area was divided into attraction space and non-attraction space. Attraction space is mainly for full-scale play content areas and the non-attraction space is to enforce the attraction space experience. Roger Caillois's play theory states that there are 4 play types; Illinx, Mimicry, $Ag{\hat{o}}n$, and Alea. All 4 play types were shown through attraction and Mimicry at non-attraction. Each cast costume was analyzed in terms of apparel design elements - silhouette, textile, color, detail, and props - related to play type facility and cast role. Criteria for theme park cast costume designs were suggested based on the results. Illinx cast members who fulfill a safety-checking role wear high chroma warm color costumes with the accent on details in bodice cutting lines, collar edges, pockets, buttons and decorative ornaments. A complementary contrast is also used. The guidance cast in Illinx may wear a suit in bright/vivid color. Mimicry guidance cast costumes show meticulous perfection in imitation with the figure in its space. From head to toe, color, textile, and silhouette - every detail and even props should match the character. $Ag{\hat{o}}n$ cast costumes are strictly limited in detail and decorative ornament usage as well as in color, since they are in charge of the management and operation of a competition. Alea cast's role is a self-demonstrator. Alea cast members should be a real tarot card reader. However, a manual should control their costumes. A total of 10 cast roles at a non-attraction space should be designed to show job patterns clearly in accordance with the whole theme at the park.

• Safety and Health at Work
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• v.7 no.3
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• pp.208-212
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• 2016

Background: Outdoor workers are at risk of high ultraviolet radiation exposure, and may have difficulty using sun protection. The objectives were to determine the prevalence of sun protection behaviors in a sample of outdoor construction workers, and to assess which factors predict better sun protection practices. Methods: Participants were recruited via construction unions. Workers answered a questionnaire on demographics, skin cancer risk, sun protection behaviors, and job. Sun protection behavior scores (from questions on sunscreen use, sleeved shirt, hat, shade seeking, sunglasses) were calculated by converting Likert-scale answers to scores from 0 to 4, and taking the mean (separately for work and leisure). Determinants of sun protection behavior scores were examined for work and leisure using generalized linear models. Results: Seventy-seven workers had complete questionnaire data (participation 98%). Sun protection behaviors used most often were hats (79% often/always) and sleeved shirts (82% often/always); least prevalent were shade-seeking (8% often/always) and sunscreen (29% often/always). For both work and leisure scores, the strongest predictor was skin type, with fairer-skinned individuals having higher sun protection behavior scores. Workers had higher scores at work than on weekends. Workplaces that required hats and sleeved shirts for safety purposes had higher protection behavior scores. Conclusion: This high-participation rate cohort helps characterize sun protection behaviors among outdoor workers. Workers practiced better sun protection at work than on weekends, suggesting that workplace policies supportive of sun protection could be useful for skin cancer prevention in the construction industry.

• Journal of the Korean Society of Safety
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• v.21 no.6 s.78
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• pp.7-13
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• 2006

A transient heat transfer and thermal stress analysis for a brake drum of commercial vehicles have been performed by ANSYS code in the cases of single braking and the repeated braking condition. The temperature and thermal stress distributions in the brake drum under various braking conditions were obtained using a two-dimensional axisymmetric model. In case of deceleration of 0.3G with an initial vehicle speed of 60km/h, the maximum temperature in the drum was $87.6^{\circ}C$ after braking application. The maximum stress of 78.7MPa in the drum occurred at the intersection between the flange and hat under a condition in which repeated 15 cycles braking with an initial vehicle speed of 60km/h and a deceleration of 0.3G is applied to according to KS R1129. The maximum stress value is much lower than the yield strength of drum material(FC250).

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.11
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• pp.1520-1529
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• 2007

Workers on construction sites are exposed to multiple and varied threats. Of those, climatic factors such as high/low air temperatures and high/low humidity have a bad mental and physical health effect on workers. Especially, work in hot environment has a tendency to cause fatigue, reduce productivity and increase the incidence of accident. So, the purpose of this research was to understand working clothes and working environment of workers at a construction site in summer. The depth interview was performed by 45 workers of 4 different construction sites and the results were as follows. Workers wore average 4 items as clothing(upper, lower) and average 5 items as personal protective equipments(PPEs). They answered "head" is the hottest body area and must be protected during working. This means the necessity of development in safety hat. In addition, it should be developed working clothes and gaiters for alleviating heat stress and safety shoes for diminishing weight. It is expected that this research plays basic and important rolls to develop PPEs for reducing the heat stress of construction workers.