• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.4
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• pp.13-18
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• 2007

The research was performed to review the design factors which affect the durability of structures. For the study, domestic and foreign literature review were performed on various design criteria. Based on Korean standard specifications, the results showed that the durability of structure as the diameter of reinforcing steel bar becomes smaller and the distance between reinforcing bar is closer than the normal gap. The results were also presented that the minimum required bar cover is 6.6cm to obtain the durability index value. In addition, the maximum limited bar cover was 12cm considering the durability index and the change of increasing value of durability index. In case that there is no specified regulation for the bar cover thickness change, the durability life by neutralization is proportional to the thickness of bar cover.

• The Korean Journal of Applied Statistics
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• v.28 no.6
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• pp.1227-1234
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• 2015

Traditional criteria for optimum experimental designs depend on the specifications of the model; however, there will be a dilemma when we do not have perfect knowledge about the model. Box and Draper (1959) suggested one direction to minimize bias that may occur in this situation. We will demonstrate some examples with exact solutions that provide a no-bias design for polynomial regression. The most interesting finding is that a design that requires less bias should allocate design points away from the border of the design space.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2001.06a
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• pp.129-132
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• 2001

she purpose of this paper is to propose an approach to suppress the vibration of three-mass inertia system based on the LMI theory. and confirm its validity through simulations under the condition of parameter variation. First, the existing $H_{\infty}$ servo problem is modified to a structure to which the LMI theory can be applied by virtue of the interval model principle. By adopting this structure, we can divide given specifications fur the vibration suppression problem into $H_2$and $H_{\infty}$ performance criteria. The results of simulation for the three-mass inertia system show that the proposed design approach is quite effective.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.201-204
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• 2017

An comparative analysis between two engine type certification specifications which are FAR Part 33 and EASA CS-E has been performed to provide fundamental information for validity assessment of civil certified engine when it is installed to a military rotorcraft. The analysis result has been used to build a traceability information between CS-E and MIL-HDBK-516C by which the substantiation data for engine type certification can be used as parts of aircraft propulsion system airworthiness substantiation.

• International Journal of Highway Engineering
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• v.3 no.2 s.8
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• pp.113-121
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• 2001

Among the currently available binder specifications, Superpave Performance Grade asphalt specification is regarded as a superior specification on its theoretical background as well as pavement performance relationship. Many difficulties are expected; however, for Superpave implementation in Korea because of heavy burden of equipment cost as well as lack of trained personnel in asphalt industry, which may too much barrier to overcome in Korean situation. As an effort to improve qualify of asphalt binder, recently, people discuss about a possibility of constituting a performance-based asphalt specification using rather easy-to-measure asphalt properties. The objective of this paper is to determine the possibility of constituting a performance-based asphalt specification using an empirical asphalt properties, such as penetration ring and ball softening point rather than using fundamental properties of asphalt. Nine straight asphalts, that covers entire straight asphalt from all Korean refineries, and eighteen modified asphalts that were modified from two modifiers were included in the study. An analysis was made through a comparison between empirical properties and Superpave PG criteria. This study concluded that it may possible to constitute a pseudo-Superpave-like specification using an empirical asphalt properties as a specification criteria. Therefore, more systematic research is needed to constitute the asphalt specification.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.77-85
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• 2020

Currently, life-cycle cost analysis methods are introduced to maintain large infrastructure facilities in Korea. However, there are not many cases in which maintenance models are applied that reflect conditions such as the location of a facility and its surroundings. In order to establish an appropriate maintenance strategy, a cost prediction, deterioration model, and a decision model reflecting uncertainty should be established. In this study, an economic analysis model was developed for long-term cost planning and management based on user decisions based on maintenance methods and judgment criteria for painting specifications applied to power generation structures. The performance of the paintwork was assessed through the paint deterioration test for the application of the economic analysis model, and the results of the economic analysis according to the applied paint specifications (Urethan, polysiloxane, fluorine) were verified by applying the proposed economic analysis model. In this study, it is believed that the selection of the repair cycle and evaluation methods applied with the development model rather than the performance of the painting can be expected to be used as basic data for the maintenance cycle, even if it is not limited to the painting.

• Journal of Microbiology and Biotechnology
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• v.31 no.7
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• pp.956-966
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• 2021

To prevent the outbreak of infectious diseases that inflict huge economic and social losses, domestic livestock farms and related facilities have introduced automatic and semiautomatic disinfectant solution-spraying systems for vehicles. However, the facility standards and specifications vary by manufacturer, and no scientific performance evaluation has been conducted. The puropose of this study is to develop physical and biological evaluation methods. Physical and biological appraisals were conducted using two types of disinfection facilities (tunnel- and U-type) and two types of vehicles (passenger car, truck). Water-sensitive paper was used to evaluate the physical performance values for the disinfection facilities. In addition, to assess their biological performance, carriers containing low-pathogenic avian influenza virus were attached to vehicles, and the viral reduction was measured after the vehicles moved through the facility. The tunnel-type had rates of coverage in the range of 70-90% for the passenger car and 60-90% for the truck. At least 4-log virus reduction after spraying for 1-5 min was shown for both vehicles. For the U-type facility evaluation, the coverage rates were in the range of 60-90% for the passenger car and at least 90% for the truck. More than 4-log viral reduction was estimated within a spraying time of 5 min. To reduce viruses on the surface of vehicles by at least 4 log within a short period, the disinfectant solution should cover at least 71% of the pathogens. In conclusion, we were able to assess the physical and biological performance criteria for disinfection facilities aboard transportation vehicles.

• Journal of Sensor Science and Technology
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• v.24 no.5
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• pp.319-325
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• 2015

While the conventional personal protective equipments (PPEs) covers a variety of devices and garments such as respirators, turnout gear, gloves, blankets and gas masks, several electronic devices such as personal alert safety system (PASS) and heads-up displays in the facepiece have become a part of firefighters personal protective equipments through past several years. Furthermore, more advanced electronic sensors including location traking sensor, thermal imaging caerma, toxic gas detectors, and even physiological monitoring sensors are being integrated into ensemble elements for better protection of firefighters from fire sites. Despite any electronic equipment placed on the firefighter must withstand environmental extremes and continue to properly function under any thermal conditions that firefighters routinely face, there are no specific criteria for these electronics to define functionability of these devices under given thermal conditions. Although manufacturers provide the specifications and performance guidelines for their products, their operation guidelines hardly match the real thermal conditions. Present study overviews firefighter's fatalities and thermal conditions that firefighters and their equipments face. Lastly, thermal packaging methods that we have developed and tested are introduced.

• Fashion & Textile Research Journal
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• v.12 no.5
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• pp.633-641
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• 2010

The purpose of this study is to evaluate a new flight suit in bilateral ways; subjectively and objectively in the improvements of comfort and mobility. Seven healthy males at the age of twenties volunteered in this wearing test. They were over 177 cm in height and 92-95 cm in chest circumference, which satisfies the M95 Special' size described in the Korean Military Specifications and Standards. The subjective satisfaction was evaluated according to the criteria of ease of donning and doffing, fitness of wear, mobility, space between cloth and body, convenience in using restroom. Subjective satisfaction evaluation says that the best improvement of movement are neck circumference, chest breadth, armscye circumference, waist back length, crotch length, crotch height and body rise. According to the evaluation, improvements of mobility were conspicuous especially in parts of body like neck, breast, waist, back, and arms. When evaluating objective satisfaction, we measured a angle difference in a prescribed standard-grid on a photograph that picked up while the subject performed each motion in front of 10 cm-interval grid. As a result, the motion that had angle difference above 5 degrees were arm stretching and standing on single leg holding at forward or at his side. Bending necks and waist, crouching also had angle difference of over 5 degrees. The improvements are discussed from the viewpoint that the increased ease in parts of armscye circumference and crotch in new flight suit pattern.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.4
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• pp.27-35
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• 2018

Purpose: The diverse users and the increase of power wheelchair users have made it difficult to apply the standards of Wheelchair user accessible toilet rooms for the existing law and BF-certification. To address these issues, the standards of the relevant laws have been improved (Ministry of Health and Welfare, 2018), but there are still many problems. In this study, problems with the standards for Wheelchair user accessible toilet rooms in Korea are analyzed by comparing national and international standards. In addition, improvements to standards for Wheelchair user accessible toilet rooms will be suggested. Method: It presents improvement for standards of Wheelchair user accessible toilet rooms by comparing national, international standard and standards of many countries. Korean standard, International Standard(ISO 21542), American Standard(ADA Standards), German Standard(DIN 18040-1), Austrian Standard($\ddot{O}NORM$ B 1600) and Swiss Standard(Norm SIA 500) were investigated and analyzed. Results: Korea's standards differ from the ISO and the Standards of other countries in many ways, so there is a need for realignment. Specifications for disabled toilets and clear criteria for the size, shape, and location of sanitary appliances in toilets that are practically available to wheelchair users should be provided. Considering the increasing number of disabled toilet users, the installation of various disabled toilet rooms should be considered considering the user characteristics of those who can walk and wheelchair users. Implication: Recent partial improvements to relevant laws cannot meet the requirements of various users. Therefore, comprehensive and clear standard should be presented that take into account changing society and the environment.