• Title/Summary/Keyword: maintenance Standard

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A Study on Proving RMF A&A in Real World for Weapon System Development (무기체계 개발을 위한 RMF A&A의 실증에 관한 연구)

  • Cho, Kwangsoo;Kim, Seungjoo
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.31 no.4
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    • pp.817-839
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    • 2021
  • To manage software safely, the military acquires and manages products in accordance with the RMF A&A. RMF A&A is standard for acquiring IT products used in the military. And it covers the requirements, acquisition through evaluation and maintenance of products. According to the RMF A&A, product development activities should reflect the risks of the military. In other words, developers have mitigated the risks through security by design and supply chain security. And they submit evidence proving that they have properly comply with RMF A&A's security requirements, and the military will evaluate the evidence to determine whether to acquire IT product. Previously, case study of RMF A&A have been already conducted. But it is difficult to apply in real-world, because it only address part of RMF A&A and detailed information is confidential. In this paper, we propose the evidence fulfilling method that can satisfy the requirements of the RMF A&A. Furthermore, we apply the proposed method to real-world drone system for verifying our method meets the RMF A&A.

Groundwater control measures for deep urban tunnels (도심지 대심도 터널의 지하수 변동 영향 제어 방안)

  • Jeong, Jae-Ho;Kim, Kang-Hyun;Song, Myung-Kyu;Shin, Jong-Ho
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.6
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    • pp.403-421
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    • 2021
  • Most of the urban tunnels in Korea, which are represented by the 1st to 3rd subways, use the drainage tunnel by NATM. Recently, when a construction project that actively utilizes large-scale urban space is promoted, negative effects that do not conform to the existing empirical rules of urban tunnels may occur. In particular, there is a high possibility that groundwater fluctuations and hydrodynamic behavior will occur owing to the practice of tunnel technology in Korea, which has mainly applied the drainage tunnel. In order to solve the problem of the drainage tunnel, attempts are being made to control groundwater fluctuations. For this, the establishment of tunnel groundwater management standard concept and the analysis of the tunnel hydraulic behavior were performed. To prevent the problem of groundwater fluctuations caused by the construction of large-scale tunnels in urban areas, it was suggested that the conceptual transformation of the empirical technical practice, which is applied only in the underground safety impact assessment stage, to the direction of controlling the inflow in the tunnel, is required. And the relationship between the groundwater level and the inflow of the tunnel required for setting the allowable inflow when planning the tunnel was derived. The introduction of a tunnel groundwater management concept is expected to help solve problems such as groundwater fluctuations, ground settlement, depletion of groundwater resources, and decline of maintenance performance in various urban deep tunnel construction projects to be promoted in the future.

A Study on Facility Changes according to Changes in the Urban Park Type in Korea - Focus on Parks in Seoul - (국내 도시공원 유형변경에 따른 시설변화 연구 - 서울시 공원을 중심으로 -)

  • Ko, Ha-jung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.2
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    • pp.76-88
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    • 2022
  • Urban parks play the role of providing leisure spaces for people in their everyday life along with serving ecological functions in the city. Although urban parks aim to satisfy the needs of users visiting the park, most urban parks are currently uniformly created and maintained without considering the environmental characteristics based on the needs of users. This study thus analyzed parks that underwent modifications in line with the revised Park Act in 2005. There were 45 parks whose types were legally changed, of which 21 were changed from children's parks to small parks, and 19 were changed to utilize and highlight the themes such as cultural parks and historical parks. Among the parks whose types have changed, the ratio of amenities in cultural and historic parks has increased, while the facility area in small parks has decreased and the green area has increased in its place. As a result of analyzing the changes to the park facility area, it was confirmed that increasing park amenities has a positive effect in pursuing revitalization of use through park maintenance, but has a negative consequence of significantly decreasing green area. It is necessary to reorganize the park type classification system to reflect the park environment and prepare guidelines for a new installation standard by park type to expand the net function of parks in cities and maintain the sustainable ecological environment. Through in-depth discussions on the facilities of park types, it is anticipated that innovative and multilateral research could be conducted to prepare improvement measures tailored to the guidelines of urban park types in years to come.

A Study on the Design of Planterior to Reduce and Purify Indoor Particle Matters (PM) (실내 미세먼지 저감을 위한 플랜테리어 디자인 연구)

  • Ahn, SeungWon;Jeong, Jun Hyun
    • Journal of the Korean Society of Floral Art and Design
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    • no.44
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    • pp.3-31
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    • 2021
  • To verify the types of effects that plants have in our general living conditions, I examined an air quality in living rooms of the three, 129.78m2 size, apartments that were with and without plants. and the findings of the study were as addressed below. 1) Experiments showed no statistically significant differences in Case A. However, in Case B and Case C, the standard deviation of PM10, PM2.5 and PM 1.0 verified that each had statistically significant (p<.01) differences. 2) It is believed that the effect of reducing particle matters due to the installation of plants in the indoor space is to vary significantly depending on the indoor environmental conditions, the cleanliness of the room, and the amount of furniture and may also differ depending on the daily dietary cooking method. In addition, it is believed that the planterior will not only reduce indoor fine dust, but also reduce the psychological comfort and eye fatigue of the residents. Nevertheless, supplementary research is needed. 3) In the planterior design for reducing indoor particle matters, various measures were examined. Among them, the vertical wall design method was tested and suggested through empirical experiments. In addition, maintenance methods were proposed depending on the type of indoor plant.

A Study of Improvements in the Standards of Cost Estimate for the New Excellent Technology in Construction (건설 신기술의 원가산정기준 개선방안에 대한 연구)

  • Lee, Ju-hyun;Tae, Yong-Ho;Baek, Seung-Ho;Kim, Kyoungmin
    • Korean Journal of Construction Engineering and Management
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    • v.23 no.5
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    • pp.65-76
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    • 2022
  • The New Excellent Technology (NET) designation system, introduced in 1989 for the purpose of promoting the development of domestic construction technology and enhancing national competitiveness, reviews the statement of construction cost of new technologies. And the cost reduction effect such as design, construction, and maintenance cost and the effect of reducing the construction duration are evaluated as an evaluation criteria of economic feasibility. However, in this evaluation process, differences of opinion between the institution of construction cost estimating standard management and the new technology developer about unique technologies frequently occur. In addition it is difficult to objectively compare the construction duration with existing similar technologies because there is no information on productivity as the current cost estimating standards for new technologies only present the required amount per unit quantity. In this study, the current state of cost estimating criteria review procedure, evaluation criteria, and cost estimating standards establishment method were analyzed when screening for the designation of a new construction technologies, and compared with overseas cost estimating standards, measures to improve the cost estimating standards of current construction new technologies were suggested. Through the improved cost estimating standards of this study, it is expected that cost information on new technologies will be provided to clients in more detail than the current ones, and the availability and applicability of new construction technologies would be improved by simplifying the construction cost calculation process more.

A Case Study of Risk Assessments and Safety Measures in a PCB Manufacturing Process (인쇄회로기판 제조 공정에서 위험성평가와 안전조치 적용 사례 연구)

  • Lee, Young Man;Lee, Inseok
    • Journal of the Korean Society of Safety
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    • v.37 no.4
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    • pp.120-128
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    • 2022
  • Printed circuit boards (PCBs) are a basic component in the electronics industry and are widely used in nearly all electronic products, such as mobile phones, tablet computers, and digital cameras, as well as in electric equipment. PCB manufacturing involves the use of many chemicals and chemical processes and therefore has more risks than other manufacturing sectors. This study aims to identify the causes of possible accidents during PCB manufacturing through risk assessment, develop and implement safety measures, and evaluate the effectiveness of these measures. Note that the safety measures developed to mitigate the risks of a certain process were also implemented for other similar processes. The risk assessments conducted over seven years, from 2015 to 2021, at a PCB manufacturing company identified 361 hazardous processes. Between 2016 and 2019, 41-56 hazardous processes were identified per year; such processes decreased to fewer than 20 per year after 2020. Application of the risk assessment results to the improvement of the hazardous processes with the similar characteristics seems to be effective in decreasing the risks. Equipment-related factors such as lack of appropriate maintenance, low work standards, and defective protection devices were responsible for 59.8% of all possible accidents. Because PCB manufacturing involves many chemicals, skin contact with hazardous substances, electric shock, fire, and explosion were the most common types of possible accidents (81.7%). In total, 505 safety measures were implemented, including 157 related to purchase and improvement of equipment and devices for safety (31.1%), 147 related to the installation/modification of fire prevention facilities (29.1%), and 69 related to the use of standard electrical appliances (13.7%). Risk assessment conducted after implementing the safety measures showed that these measures significantly decreased risk; 247 processes (68.4%) had a risk level of 3, corresponding to "very low," and 114 processes (31.6%) showed a risk level of 4, corresponding to "low." In particular, risk assessment of 104 processes with risk scores of 12 and 10 other processes with risk score of 16 showed that the risk decreased to 4 after implementing the safety measures. Thus, implementing these measures in similar manufacturing sectors that involve chemical processes can mitigate risk.

Saudi Experts Consensus on Diagnosis and Management of Pediatric Functional Constipation

  • Alshehri, Dhafer B.;Sindi, Haifa Hasan;AlMusalami, Ibrahim Mohamod;Rozi, Ibrahim Hosamuddin;Shagrani, Mohamed;Kamal, Naglaa M.;Alahmadi, Najat Saeid;Alfuraikh, Samia Saud;Vandenplas, Yvan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.25 no.3
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    • pp.163-179
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    • 2022
  • Although functional gastrointestinal disorders (FGIDs) are very common in pediatric patients, there is a scarcity of published epidemiologic data, characteristics, and management patterns from Saudi Arabia, which is the 2nd largest Arabic country in terms of area and the 6th largest Arabic country in terms of population, with 10% of its population aged <5 years. Functional constipation (FC) is an FGID that has shown a rising prevalence among Saudi infants and children in the last few years, which urges us to update our clinical practices. Nine pediatric consultants attended two advisory board meetings to discuss and address current challenges, provide solutions, and reach a Saudi national consensus for the management of pediatric constipation. The pediatric consultants agreed that pediatricians should pay attention to any alarming signs (red flags) found during history taking or physical examinations. They also agreed that the Rome IV criteria are the gold standard for the diagnosis of pediatric FC. Different therapeutic options are available for pediatric patients with FC. Dietary treatment is recommended for infants with constipation for up to six months of age. When non-pharmacological interventions fail to improve FC symptoms, pharmacological treatment with laxatives is indicated. First, the treatment is aimed at disimpaction to remove fecal masses. This is achieved by administering a high dose of oral polyethylene glycol (PEG) or lactulose for a few days. Subsequently, maintenance therapy with PEG should be initiated to prevent the re-accumulation of feces. In addition to PEG, several other options may be used, such as Mg-rich formulas or stimulant laxatives. However, rectal enemas and suppositories are usually reserved for cases that require acute pain relief. In contrast, infant formulas that contain prebiotics or probiotics have not been shown to be effective in infant constipation, while the use of partially hydrolyzed formula is inconclusive. These clinical practice recommendations are intended to be adopted by pediatricians and primary care physicians across Saudi Arabia.

A Study on Method to Activate the Operation of a Fire Safety Experience Center Based on Virtual Reality (가상현실 기반 소방안전체험관 운영 활성화 방안 연구)

  • Young Sook Kim;Kwangsu Moon
    • Journal of the Society of Disaster Information
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    • v.18 no.4
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    • pp.713-728
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    • 2022
  • Purpose: This study examined the effect of VR safety education content quality on behavioral intention and collect operational opinions through interview. Method: Based on the survey data of 93 former and current officers, the hypothesis was verified. In addition, 15 fire safety experience centers were visited to conduct interview. Result: For the quality of VR safety education contents, immersion and convenience had a significant effect on usage satisfaction, recommendation intention, and field application intention. In addition, convenience and aesthetic experience had a significant effect on the educational effect, but immersion and diversity did not significant. In the interview, they suggested that VR education has high user satisfaction and good educational effects. The quality of content(particularly immersion and convenience) is an important factor in VR education. In the long-term persepective, it is necessary to prepare a standard teaching plan for each disaster, in addition, manpower, expertise, maintenance problems, and etc. Conclusion: Through these results, it was confirmed that VR experience content quality affects behavioral intention and educational effect and that efforts and investments to improve content quality are needed to enhance the effectiveness of VR experience education. And the contents derived from the interview will be helpful in the operation of an effective fire safety experience center.

Air Pollutant Removal Rates of Concrete Permeable Blocks Produced with Coated Zeolite Beads (코팅된 제올라이트 비드를 이용한 콘크리트 투수블록의 대기전구물질 제거율 평가)

  • Park, Jun-Seo;Yang, Keun-Hyeok
    • Journal of the Korea Institute of Building Construction
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    • v.23 no.2
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    • pp.153-164
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    • 2023
  • The objective of this study is to examine the removal rate of air pollutants, specifically sulfur oxides (SOx) and nitrogen oxides(NOx), using concrete permeable blocks containing zeolite beads coated with materials capable of eliminating these pollutants. Titanium dioxide(TiO2) powder and coconut shell powder were utilized for the removal of SOx and NOx and were applied as coatings on the zeolite beads. Concrete permeable block specimens embedded with the coated zeolite beads were produced using an actual factory production line. Test results demonstrated that the concrete permeable block containing zeolite beads coated with coconut shell powder in the surface layer achieved SOx and NOx removal rates of 12.5% and 99%, respectively, exhibiting superior performance compared to other blocks. Additionally, the flexural strength and slip resistance were 5.3MPa and 65BPN or higher, respectively, satisfying the requirements specified in KS F 4419 and KS F 4561. Conversely, the permeability coefficient exhibited low permeability, with grades 2 and 3 before and after contaminant pollution, according to the standard for 'design, construction, and maintenance of pavement using permeable block'. In conclusion, incorporating zeolite beads coated with coconut shell powder in the surface layer enables simultaneous removal of SOx and NOx, irrespective of ultraviolet rays, while maintaining adequate flexural strength and slip resistance. However, the permeability is significantly reduced, necessitating further improvements.

Risk Assessment of Marine LPG Engine Using Fuzzy Multicriteria HAZOP Technique (퍼지 다기준 HAZOP 기법을 이용한 해상용 LPG 엔진의 위험성 평가)

  • Siljung Yeo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.238-247
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    • 2023
  • Liquefied petroleum gas (LPG) is an attractive fuel for ships considering its current technology and economic viability. However, safety guidelines for LPG-fueled ships are still under development, and there have been no cases of applying LPG propulsion systems to small and medium-sized ships in Korea. The purpose of this study was to perform an objective risk assessment for the first marine LPG engine system and propose safe operational standards. First, hazard and operability (HAZOP) analysis was used to divide the engine system into five nodes, and 58 hazards were identified. To compensate for the subjectivity of qualitative evaluation using HAZOP analysis, fuzzy set theory was used, and additional risk factors, such as detectability and sensitivity, were included to compare the relative weights of the risk factors using a fuzzy analytical hierarchy process. As a result, among the five risk factors, those with a major impact on risk were determined to be the frequency and severity. Finally, the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS) was applied to select the risk rank more precisely by considering the weights of the risk factors. The risk level was divided into 47 groups, and the major hazard during the operation of the engine system was found through the analysis to be gas leakage during maintenance of the LPG supply line. The technique proposed can be applied to various facilities, such as LPG supply systems, and can be utilized as a standard procedure for risk assessment in developing safety standards for LPG-powered ships.