• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.506-513
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• 2021

The durability and safety of reinforced concrete structures significantly depend on the reinforcement conditions, concrete cover thickness, cracks, and concrete strength. There are two ways to accurately determine the information on reinforcing bars embedded in concrete - the local destructive method and the non-destructive rebar detection test. In general, the non-destructive rebar detection tests, such as the electromagnetic wave radar method, electromagnetic induction method, and radiation method, are adopted to avoid damage to the structural elements. The moisture content and temperature of concrete affect the dielectric constant, which is the electrical property of concrete, and cause interference in the non-destructive rebar detection test results. Therefore, in this study, the effects of the electromagnetic wave radar method and electromagnetic induction method have been analyzed according to the temperature and surface moisture content of concrete. Due to the technological advancement and development of equipment, the average error rate was less than 5% in the specimens at 24℃, irrespective of their operating principles. Among the tested methods, the electromagnetic induction method showed very high accuracy. The electromagnetic wave radar method indicated a relatively small error rate in the dry state than in the wet state, and exhibited a relatively high error rate at high temperatures. It was confirmed that the error could be reduced by applying the electromagnetic wave radar method when the temperature of the probe was low and in a dry state, and by using the electromagnetic induction method when the probe was in a wet state or at a high temperature.

• Journal of the Korean Geosynthetics Society
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• v.21 no.4
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• pp.21-29
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• 2022

The room-and-pillar method or grid-type underground space is a method of forming a space by excavating the excavation part at regular intervals so that it is orthogonal and using natural rock mass as a structure. Such excavation may appear different in size from the excavation stage where the maximum displacement occurs depending on the excavation direction and sequence. In this study, considering the installation of support materials such as shotcrete and rock bolts for the optimal design of the excavation process, the safety and constructability of the design and construction of the grid-type underground space under specific ground conditions were analytically reviewed. The ground conditions were set using an numerical method, and the stress at pillar and displacement at center of room were considered for each excavation stage and construction type under a constant surcharge. The height of the space was 8m, which was set higher than the size of a general office, and was reviewed in consideration of equipment and plant facilities. In addition, the degree of displacement control according to the installation of support materials was reviewed in consideration of shotcrete and rock bolts.

• Journal of the Korean Society of Radiology
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• v.16 no.2
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• pp.169-175
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• 2022

In this study, envisioned a laboratory equipped with virus blocking equipment for chest X-ray examinations of respiratory or droplet-transmitted virus-infected patients, and the material with the least deterioration in X-ray output and image quality among the proven blocking materials that block viruses in the design process. and experimented to find the thickness. As a result, when 1 cm of acrylic was applied, the X-ray output was reduced by only about 3.27 % compared to the absence of the barrier material, the SNR was 40.7 and CNR was 30.9, which was the best. The SSIM index result was analyzed as 0.891, which was analyzed to be implemented as the most similar image compared to the original image. The barrier material applied in the research method was objective in that it used a product approved by the Ministry of Food and Drug Safety. the results of this study are expected to provide useful information when installing X-ray examination facilities for the diagnosis and treatment of respiratory-related virus-infected patients in the future.

• Journal of The Korea Institute of Healthcare Architecture
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• v.28 no.3
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• pp.47-54
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• 2022

Purpose: This study presents the analysis on space usage of delivery departments in regional public hospitals. The results intention is to achieve improvement of the delivery environment for the mothers and newborns regarding exposure prevention and efficient infection control. The purpose of this study is to provide fundamental data for architectural plans and guidelines for the delivery department. Method: The investigation and analysis were based on research papers, legal systems, public medical statistical data, and the architectural floor plan drawing. For research, 20 regional public hospitals with an operating delivery room were excluded. Regarding data accessibility, 15 regional public hospitals were selected. Results: To overcome the increased vulnerability of the delivery department, the research results of basic data is provided for the establishment to address urgent needs and rapid response. Thus, the research results are as follows: Firstly, the delivery department needs to respond promptly according to the type of patients. For example, in a case of emergency surgery, a connected circulation plan with the related departments is needed. Secondly, for the environment of the delivery area, alleviating anxiety is imperative for pregnant patients and guardians, labor, childbirth, and recovery. Therefore, these needs must be addressed for treatment space and circulation. Lastly, the delivery department is classified into three areas for analysis: access area, treatment area, and support area. In most of the delivery departments of the 15 selected hospitals, there is no space for the access and support area except for the labor and delivery rooms in the treatment area. For the access area, a waiting area, changing room for pregnant women and guardians, and a storage space for contaminated linens are required for infection prevention, safety, and efficiency. For the treatment area, childbirth processes and circulation should have space reserved for labor, delivery, recovery, examination, and treatment. In preparation for an emergency during childbirth, emergency response measures and supporting space needs to be established. For the support area, circulation and rooms are to be designed for medical staff support, activity space, storage and transportation of equipment, and urgent medical treatment. Implications: Along with the low fertility rate and the decrease of medical institutions that operate delivery departments, for the purpose of establishing a public medical service system and a healthy medical environment for mothers and newborns, the researched information demonstrates basic data on space plan of delivery departments in regional public hospitals.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1246-1246
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• 2001

The quality of meat is highly variable in many properties. This variability originates from both animal production and meat processing. At the pre-slaughter stage, animal factors such as breed, sex, age contribute to this variability. Environmental factors include feeding, rearing, transport and conditions just before slaughter (Hildrum et al., 1995). Meat can be presented in a variety of forms, each offering different opportunities for adulteration and contamination. This has imposed great pressure on the food manufacturing industry to guarantee the safety of meat. Tissue and muscle speciation of flesh foods, as well as speciation of animal derived by-products fed to all classes of domestic animals, are now perhaps the most important uncertainty which the food industry must resolve to allay consumer concern. Recently, there is a demand for rapid and low cost methods of direct quality measurements in both food and food ingredients (including high performance liquid chromatography (HPLC), thin layer chromatography (TLC), enzymatic and inmunological tests (e.g. ELISA test) and physical tests) to establish their authenticity and hence guarantee the quality of products manufactured for consumers (Holland et al., 1998). The use of Near Infrared Reflectance Spectroscopy (NIRS) for the rapid, precise and non-destructive analysis of a wide range of organic materials has been comprehensively documented (Osborne et at., 1993). Most of the established methods have involved the development of NIRS calibrations for the quantitative prediction of composition in meat (Ben-Gera and Norris, 1968; Lanza, 1983; Clark and Short, 1994). This was a rational strategy to pursue during the initial stages of its application, given the type of equipment available, the state of development of the emerging discipline of chemometrics and the overwhelming commercial interest in solving such problems (Downey, 1994). One of the advantages of NIRS technology is not only to assess chemical structures through the analysis of the molecular bonds in the near infrared spectrum, but also to build an optical model characteristic of the sample which behaves like the “finger print” of the sample. This opens the possibility of using spectra to determine complex attributes of organic structures, which are related to molecular chromophores, organoleptic scores and sensory characteristics (Hildrum et al., 1994, 1995; Park et al., 1998). In addition, the application of statistical packages like principal component or discriminant analysis provides the possibility to understand the optical properties of the sample and make a classification without the chemical information. The objectives of this present work were: (1) to examine two methods of sample presentation to the instrument (intact and minced) and (2) to explore the use of principal component analysis (PCA) and Soft Independent Modelling of class Analogy (SIMCA) to classify muscles by quality attributes. Seventy-eight (n: 78) beef muscles (m. longissimus dorsi) from Hereford breed of cattle were used. The samples were scanned in a NIRS monochromator instrument (NIR Systems 6500, Silver Spring, MD, USA) in reflectance mode (log 1/R). Both intact and minced presentation to the instrument were explored. Qualitative analysis of optical information through PCA and SIMCA analysis showed differences in muscles resulting from two different feeding systems.

• Journal of Environmental Health Sciences
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• v.49 no.4
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• pp.183-189
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• 2023

Background: The indoor air quality of classrooms, in which the capacity per unit area is high and students spend time together, must be managed for safety and comfort. It is necessary to develop an eco-friendly indoor air quality reduction method rather than biased management that relies solely on air purifiers. Objectives: In this study, plants and air purifiers were installed in middle school classrooms to evaluate the indoor PM_2.5 reduction. Methods: Four middle school classrooms were selected as test beds. Air quality was monitored in real-time every one minute using IoT equipment installed in the classrooms, corridors, and rooftops. After measuring the background concentration, plants and air purifiers were installed in the classroom and the PM_2.5 reduction effect was analyzed through continuous monitoring. Results: After installing the plants and air purifiers, the average PM_2.5 concentration was 33.7 ㎍/m³ in the classrooms without plants and air purifiers, 25.6 ㎍/m³ in classrooms with plants only, and 21.7 ㎍/m³ in classrooms with air purifiers only. In the classroom where plants and air purifiers were installed together, it was 20.0 ㎍/m³. The reduction rates before and after installation were 4.5% for classrooms with plants only, 16.5% for classrooms with air purifiers only, and 27.6% for classrooms with both plants and air purifiers. The I/O ratio, which compares the concentration of PM_2.5 in classrooms with corridors and outside air, also showed the lowest in the order of plants and air purifiers, air purifiers, and plant-only classrooms. Conclusions: The PM_2.5 reduction effect of using plants was confirmed, and it is expected to be used as basic data for the development of environmentally-friendly indoor air quality improvement methods.

• Korean Journal of Clinical Laboratory Science
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• v.55 no.3
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• pp.143-150
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• 2023

The global outbreak of COVID-19 has underscored the pressing need for robust infection control practices in pulmonary function laboratories (PFL). However, the existing guidelines and regulatory frameworks provided by relevant authorities in the country have revealed certain deficiencies in effectively addressing this significant public health crisis. This study surveyed the infection control regulations, disposable item usage, ventilation facilities, spatial separation, and the configuration of entrance doors in 51 domestic hospital facilities from Oct 1, 2021, to Nov 2, 2021. The survey findings revealed that while there was a relatively satisfactory adherence to airborne, droplet, and contact precautions with adequate awareness and utilization of personal protective equipment, the environmental disinfection practices exhibited a suboptimal performance rate of 39.22% per patient. Depending on the specific survey domains, substantial variations were observed in the utilization of disposable items (81.05%), ventilation systems (45.75%), dedicated testing spaces (80.39%), separation of administrative areas (15.69%), and the installation of automated doors (19.61%). This study not only highlights the paramount importance of infection control in PFLs within domestic medical institutions but also provides foundational data for developing and enhancing standardized guidelines that align with international benchmarks for infection control in these settings.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.1
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• pp.43-49
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• 2010

The escape connecting gallery in a tunnel on a road is one of emergency equipment to ensure safety for passer in the tunnel against the tunnel fire. Government stipulate over 500m tunnel has the cross passage at intervals of less then 250 m. However, this lump estimated interval is generated the concerns of exaggeration and under construction because peculiarity of the tunnel ex. The velocity of the tunnel airflow, an incline, degree of a fire, and innering area are not considered. The study indicate the way to estimate of the cross passage considered an incline and the velocity of the tunnel airflow for efficient application of cross passage on the tunnel design. As a result, in 0.0 m/s and 1.0 m/s of the velocity of the tunnel airflow case, the movement of smoke is influenced by the incline however, in 20 m/s case, it isn't influenced by incline much. According to the velocity of tunnel airflow and the incline, optimum interval of cross passage is not corresponded. Therefore established lump estimate that has 250 m intervals would be changed to estimate of optimum interval of cross passage that considered about the properties of tunnel, the velocity of the tunnel airflow, incline, degree of a fire and innering area of the tunnel.

• Korean Journal of Acupuncture
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• v.40 no.4
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• pp.156-168
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• 2023

Objectives : This study aimed to determine the status of thermal stimulation devices approved in Korea for medical applications over the past 10 years, and based on this, to obtain insight for future thermal treatment in Korean medical institutions. Methods : We searched the item classification list entitled "Regulations on Medical Device Items and Rating by Item" from the Ministry of Food and Drug Safety Notice No. 2021-24, 2021 (Enforced March 19, 2021; www.mfds.go.kr) for individually licensed heaters using the terms "heat" and "heating". Results : We identified 17 items of thermal stimulation product group, of which 1,308 devices were licensed by February 4, 2022, and 53.2% of them (n=696) were devices with valid permits for distribution in Korea. Among the licensed devices, heating pad systems under/overlay (electric, home use) were approved the most, but combinational stimulator (for medical use, home use; Grade 2) accounted for the highest percentage among the current valid permission. Moxibustion apparatuses were licensed separately for electrical use and non-electrical use, and occupied a low percentage of the total devices. We analyzed 307 devices that were accompanied by technical documents and found that the heat sources were wires in 145 (47.2%), infrared rays in 44 (14.3%) and ultrasonic waves in 42 (13.7%) devices. Most (83.1%) devices were used for pain relief, while other applications included beauty, cancer treatment, maintenance of infant body temperature, and healing fractures. Conclusions : Thermal stimulation devices accounted for about 0.9% of all medical devices, and among them, combinational stimulators and heating pad systems under/overlay had the most valid permits. Thermal stimulation devices using heating wires and infrared rays were the most prevalent, and most were used to relieve pain. In order to develop a range of thermal stimulation devices that can be utilized in Korean medical institutions, it is imperative that they have potential applications beyond pain management, addressing various medical purposes. To achieve this, foundational research is necessary to effectively apply diverse heat sources based on medical objectives.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.437-447
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• 2023

By actively adopting technologies from the Fourth Industrial Revolution, the port industry is trending toward new types of ports, such as automated and smart ports. However, behind the development of these ports, there is an increasing risk of cyber security incidents and threats within ports and container terminals, including information leakage through cargo handling equipment and ransomware attacks leading to disruptions in terminal operations. Despite the necessity of research to enhance cyber security within ports, there is a lack of such studies in the domestic context. This study focuses on Busan Port, a representative port in South Korea that actively incorporates technology from the Fourth Industrial Revolution, in order to discover variables for improving cyber security in container terminals. The research results categorized factors for enhancing cyber security in Busan Port's container terminals into network construction and policy support, standardization of education and personnel training, and legal and regulatory factors. Subsequently, multiple regression analysis was conducted based on these factors, leading to the identification of detailed factors for securing and enhancing safety, reliability, performance, and satisfaction in Busan Port's container terminals. The significance of this study lies in providing direction for enhancing cyber security in Busan Port's container terminals and addressing the increasing incidents of cyber security attacks within ports and container terminals.