• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.111-112
• /
• 2023

With the development of cities, the density of the population is continuously increasing as buildings become larger and more high-rise, but since the Haeundae residential complex fire in Busan in 2010, there has been a growing need to meet the fire protection performance of buildings as large-scale fires continue to occur every year. On the other hand, fire doors, which are one of the fire protection performance of buildings, have been judged unqualified in 82% of cases when fire doors constructed on the actual site were inspected after completion. The reason for this is that paper honeycomb and glasswool, which are used as core materials for fire doors, absorb moisture, reducing thermal insulation performance, and sagging due to increased weight, leading to performance degradation due to warping in empty spaces. To overcome these problems, research is underway to apply lightweight aerated concrete, an inorganic material, as a core material. Therefore, in order to select a blowing agent that produces stable bubbles prior to the production of lightweight bubble concrete for application as a fire door inner core, this study examined the physical performance according to the type of blowing agent and dilution concentration, and the following conclusions were drawn. Compared to vegetable bubbles and independent bubbles, synthetic bubbles have 3~8% higher thermal conductivity than independent bubbles, but 3~6% lower slurry density than vegetable bubbles, and 2~13% higher compressive strength, which is thought to be an improvement of synthetic bubbles.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.6
• /
• pp.628-638
• /
• 2023

Maritime Autonomous Surface ships(MASS) are gradually gaining importance. Until fully autonomous ships are developed, they will likely be controlled by remote operators who are based in a Remote Operations Center. However, there is currently no internationally or domestically established licensing for them. This issue can potentially pose a risk to navigation safety due to operations being handled by unqualified remote operators. We conducted a literature review and proposed criteria for the adoption of a licensing system for remote operators. We have futher offered alternatives to integrate this license into the existing officer licensing system, and analyzed them using Analytic Hierarchy Process(AHP). Subsequently,, theprimary need to enact legislation for remote operators is observed. The most preferred approach is to include the occupation of a remote operator in the Ship Officer Act, Article 4: Occupational Categories and Class of Licenses. Therefore, it would be logical for the organizational structure of the Remote Operation Center to mirror the traditional Bridge Resource Management. This study will contribute to the efficient training of remote operators and the safe navigation of autonomous ships with a focus on human resource management.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.1
• /
• pp.89-96
• /
• 2024

In many cases, fishing vessels operate on a schedule that leads to departure, sailing to the fishing spot, fishing, and sailing to the port of return. Consequently, most of the captains of fishing vessels operated on a single-person navigation duty system rarely have time to rest, resulting in frequent accidents owing to drowsy operation. In addition, accidents frequently occur when a tired captain leaves his duty to an unqualified seaman who does not have the basic knowledge of navigation and sleeps in the bedroom. This problem has been discussed for a long time; however, it has not been solved yet because of lack of proper countermeasures. As a measure to reduce these accidents, this article proposes a certification system for navigational-duty crew of fishing vessels.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.54 no.2
• /
• pp.173-180
• /
• 2018

Marine casualties of small fishing vessels (SFV) of less than 20 tons are frequent in Korea. The analysis was conducted to identify the cause and then prepared reduction plan using the marine casualty statistics of fishing vessels for the last five years from 2012 to 2016 by the Korean Maritime Safety Tribunal to reduce the marine casualties of SFV. According to the analysis of the type of whole vessels occurring marine casualty, fishing vessels accounted for an average 68.0 %; moreover, except for 2014 when M/V SEWOL ferry capsizing occurred, the rate of death and missing due to marine casualties occurred from 68.3 % to 91.2 % in fishing vessels, and an average 79.5 % was found to be urgent need of a measure. Marine casualties occurrence depending on the gross tonnage of fishing vessel was found that the most occurred at less than 5 tons, followed by the order of 5 to 10 tons or less. However, crews who boarded on SFV do not have any training program for them, except for the fishing safety training of fisher who carry out fishing for shipowners and crew of the coastal and offshore fishing vessel in accordance with the safety regulations for fishing vessels in the Fisheries Cooperative Association. Therefore, it is necessary to revise the training program so as to improve the preventive action and then emergency response including the fishing safety compliance with each fishery, safe navigation, machinery inspection and emergency response. Also, an SFV of less than 5 tons of 56,000 vessels is boarded by unqualified fishers. It would also be possible to consider subdividing small boat operator's certificate to enhance their qualifications. It is expected that marine casualties of SFV will be reduced if active efforts are made to improve the safety consciousness of fisher and shipowners as well as the reorganization of fishing safety training and the small boat operator's certificate system.

• The Journal of the Korea Contents Association
• /
• v.13 no.12
• /
• pp.484-493
• /
• 2013

The Korean Government has provided public rental housing to stabilize civilian dwelling. However, unreliable management of public rental housing threatens the stability of residency. This study analyzes the default of public rental housing and the cause of default through a case study, which was intended for the residents in apartment complexes in danger of default. It also suggests countermeasures to cope with the problem of public rental housing. The results are listed as follows. First, rental housing apartments contribute a lot to the housing stability policy. On the other hand, the default of housing development, which is derived from the bankruptcy of housing management companies and the negligent control of government, brings about a serious problem for housing stability. Second, although the government has made a steady effort to solve this default problem, 9000 residents from 8 apartment complexes in Korea have experienced extreme unstable residency. Third, there are many causes for the default of public rental housing such as unqualified management companies and cursory monitoring by the government. The fundamental solution is to prevent public rental housing management companies from managing, or to build a new management system of public rental housing. To solve this problem, it's recommendable to delete the application term in the special law on the default of public rental housing so that it can be applied to all default apartments. If it is not possible to perform the policy for financial reasons, a new supply of civil housing provided by private companies needs to be re-examined completely or banned.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.1
• /
• pp.56-67
• /
• 2018

With the introduction of the maritime safety supervisor system in Korea following the passenger vessel Sewol accident, the safety control system for coastal vessels has been reinforced. A maritime safety supervisor performs marine accident prevention activities by offering periodical or occasional guidance and supervision. When a deficiency is found during guidance or supervision sessions, an order for improvement is issued to rectify the problem by such measures as supplementation or replacement of vessel facilities, improvement of work hours and working conditions for employees, educational and training programs for executives and employees, or the improvement of other affairs relating to maritime safety control. However the present order for navigation suspension by a maritime safety supervisor is limited solely to supplementation or replacement. For this reason, orders for navigation suspension against other facilities is impossible, even if a serious deficiency that could lead to a marine accident such as poor cargo loading conditions or unqualified crew is identified. Therefore, the order for vessel navigation suspension to secure seaworthiness should be expanded to include cargo loading/unloading operations, certificates and documentation, maritime safety management systems, and human elements including emergency drills and working conditions, in addition to the supplementation or replacement of vessel facilities that exists.

• Microbiology and Biotechnology Letters
• /
• v.36 no.2
• /
• pp.87-95
• /
• 2008

Probiotics are live organisms that when administered in adequate amounts confer a health benefit on hosts. The administration of direct-fed microbials (DFM) such as lactobacilli and bacillus, may be a more direct approach to beneficially alter gastrointestinal microflora than altering dietary ingredients or supplementing with growth-promoting levels of antibiotics. It is apparent that microbes have an important influence on immune development and resistance to infection; that microbes are not static colonizers of our bodies, but are dynamic, symbiotic coresidents. And it can improve the surrounding environments; decrease the malodor caused by degrade the excrement. Recently, new paradigm such as environment protection and safe food have been settled. In domestic farm house, there is a great demand for probiotics as a substitute of antibiotics for the improvement of environmental quality and the production of a competitive goods. Probiotics circulated in a country have three categories: an animal medicine permitted by national veterinary research quarantine service (NVRQS), a support feed registered in city or country house, and not-registered goods. However, lots of unqualified goods were produced and circulated. And thus, it is in urgent need of evaluating the present situation and effect of probiotics. This study was conducted to evaluate the system of a probiotics as a livestock-environment improving agents for the alternation of antibiotics and quality control of it.

• Journal of Environmental Health Sciences
• /
• v.38 no.6
• /
• pp.510-519
• /
• 2012

Objectives: This study was conducted in order to evaluate the microbiological contamination of the indoor air of the lunchrooms at child care centers and investigate the toxin genes and toxin production ability of food-borne pathogens. Methods: A total of 64 child care centers were sampled to test total aerobic bacteria, coliform bacteria, fungi, Staphylococcus aureus, Bacillus cereus and Salmonella spp. according to the Korea Food Code. All toxin genes of pathogens were detected using the Polymerase Chain Reaction method. The Sthaph. aureus enterotoxin was detected by a Staphylococcus aureus enterotoxin-reversed passive latex agglutination kit. The heamolysin BL (HBL) and non-heamolytic enterotoxin (NHE) produced by B. cereus were detected using a B. cereus enterotoxin-reversed passive latex agglutination kit and Bacillus diarrheal enterotoxin visual immunoassay kit, respectively. Results: The means of total aerobic bacteria and coliform bacteria were $1.91{\pm}1.84$ log CFU/plate and $0.47{\pm}0.62$ log CFU/plate, respectively. The mean of fungi also showed $0.59{\pm}0.71$ log CFU/plate. Among the pathogenic bacteria tested in this study, Staphy. aureus and B. cereus were detected in four (6.3%) and 21 (32.8%) out of 64 indoor air samples from lunchrooms in child care centers, respectively. All Staphy. aureus tested in this study possessed no toxin genes and did not produce enterotoxin. The detection rate of nheABC, hblCDA, entFM and ces toxin gene in B. cereus was 100, 57.1, 76.2 and 0%, respectively. B. cereus isolates were classified into four groups according to the presence or absence of toxin genes. The nheABC gene was the major toxin gene among B. cereus tested in this study. The HBL was detected in 11 out of 21 B. cereus isolates (52.4%) and three B. cereus isolates produced NHE (14.3%). Conclusion: The results indicated that the contamination by microorganisms in the indoor air of lunchrooms was unqualified to supply safe catering in child care centers. The ongoing control of indoor air quality is required.

• Journal of KIISE:Databases
• /
• v.35 no.4
• /
• pp.356-367
• /
• 2008

As XML is gaining unqualified success in being adopted as a universal data representation and exchange format, particularly in the World Wide Web, the problem of querying XML documents poses interesting challenges to database researcher. Several structural XML query processing methods, including XISS and XR-tree, for past years, have been proposed for fast query processing. However, structural XML query processing has the problem of requiring expensive Join cost for twig path query Recently, sequence matching based XML query processing methods, including ViST and PRIX, have been proposed to solve the problem of structural XML query processing methods. Through sequence matching based XML query processing methods match structured queries against structured data as a whole without breaking down the queries into sub queries of paths or nodes and relying on join operations to combine their results. However, determining the structural relationship of ViST is incorrect because its numbering scheme is not optimized. And PRIX requires many processing time for matching LPS and NPS about XML data trees and queries. Therefore, in this paper, we propose efficient sequence matching method u sing the bottom-up query processing for efficient XML query processing. Also, to verify the superiority of our index structure, we compare our sequence matching method with ViST and PRIX in terms of query processing with linear path or twig path including wild-card('*' and '//').

• The Journal of the Korea Contents Association
• /
• v.11 no.5
• /
• pp.384-392
• /
• 2011

Recruitment and selection are separate but mutually reinforcing processes. The goal of recruitment is to attract the largest number of applicants possible to apply to the agency, and selection is the process of weeding out unqualified candidates and identifying qualified candidates. In this context, the recruitment and selection system of police officials is an important issue because it affects their future performance as police officers on the job, especially their policing skills, perception of society, occupational ethics. This study suggested the characteristics of U. S. recruitment and selection system of police officials. In the U. S, each police agency sets up its own recruitment and selection standards and procedures. However, recruitment and selection process follows a certain sequence : receiving application, psychological examination, background check, polygraph test, drug screening, interview, physical agility, and medical test. Special characteristic of American police system regarding recruitment and selection is that many law enforcement agencies use a polygraph test to ensure the integrity of the candidates. Another interesting screening process is a drug test because many Americans abuse illegal drugs. A candidate officer must submit urine or a hair sample for screening test. Police human resources specialists should continually identify the most innovative tests and approaches recruit and select police officers. Recruitment and selection strategies should increasingly attract and retain those officers who have the attributes to work in a community-oriented policing environment.