• Structural Engineering and Mechanics
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• v.11 no.6
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• pp.663-672
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• 2001

Numerous failures in welded connections in steel moment-resisting building frames (SMRF) were observed when buildings were inspected after the 1994 Northridge Earthquake. These observations raised concerns about the effectiveness of such frames for resisting strong earthquake ground motions. The behavior of SMRFs during an earthquake must be assessed using nonlinear dynamic analysis, and such assessments must permit the deterioration in connection strength to capture the behavior of the frame. The uncertainties that underlie both structural and dynamic loading also need to be included in the analysis process. This paper describes the analysis of one of approximately 200 SMRFs that suffered damage to its welded beam-to-column connections from the Northridge Earthquake is evaluated. Nonlinear static and dynamic analysis of this SMRF in the time domain is performed using ground motions representing the Northridge Earthquake. Subsequently, a detailed uncertainty analysis is conducted for the building using an ensemble of earthquake ground motions. Probability distributions for deformation-related limit states, described in terms of maximum roof displacement or interstory drift, are constructed. Building fragilities that are useful for condition assessment of damaged building structures and for performance-based design are developed from these distributions.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.29-37
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• 2012

The West Stone Pagoda at Gameunsaji Temple Site constructed in the 7th century is mainly composed of dark grey dacitic tuff bearing small numerous dioritic xenoliths. These xenoliths resulted in small holes due to differential weathering process from the host rocks. Physical strength of the pagoda was decreased due to weathering and damage caused by petrological, biological and coastal environmental factors. The southeastern part of the pagoda was extremely deteriorated that the rock surface showed exfoliation, fracture, open cavity, granular decomposition of minerals and salt crystallization by seawater spray from the eastern coast. The stone blocks were intersected by numerous cracks and contaminated by subsequent material such as cement mortar and iron plates. Also, the pagoda was colonized by algae, fungi, lichen and bryophytes on the roof rock surface and the gaps between the blocks. As a result of ultrasonic test, the rock materials fell under Highly Weathered Grade (HW) or Completely Weathered Grade (CW). Thus, conservational intervention is essentially required to prevent further weakening of the rock materials.

• Electronics and Telecommunications Trends
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• v.35 no.1
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• pp.60-70
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• 2020

Artificial intelligence (AI) is expected to bring about a wide range of changes in the industry, based on the assessment that it is the most innovative technology in the last three decades. The manufacturing field is an area in which various artificial intelligence technologies are being applied, and through accumulated data analysis, an optimal operation method can be presented to improve the productivity of manufacturing processes. In addition, AI technologies are being used throughout all areas of manufacturing, including product design, engineering, improvement of working environments, detection of anomalies in facilities, and quality control. This makes it possible to easily design and engineer products with a fast pace and provides an efficient working and training environment for workers. Also, abnormal situations related to quality deterioration can be identified, and autonomous operation of facilities without human intervention is made possible. In this paper, AI technologies used in smart factories, such as the trends in generative product design, smart workbench and real-sense interaction guide technology for work and training, anomaly detection technology for quality control, and intelligent manufacturing facility technology for autonomous production, are analyzed.

• Advances in environmental research
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• v.9 no.3
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• pp.151-160
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• 2020

Water quality demonstrates physical, chemical and biological characteristics of water. The quality of surface and groundwater is currently an important concern with population growth and industrialization. Over exploitation of water resources due to demand is causing the deterioration of surface water and ground water. Periodic water quality testing must be carried out to protect our water resources. The present research analyses the spatial variation of surface water and groundwater in and around the lakes of Hyderabad. Twenty-Seven lakes and their neighboring bore water samples are obtained for water quality monitoring. Samples are evaluated for specific physico-chemical parameters such as pH, Total Dissolved Solids (TDS), Cl, SO₄, Na, K, Ca, Mg, and Total Hardness (TH). The spatial variation of water quality parameters for the 27 lakes and groundwater were analysed. Correlation and multiple regression analysis were carried out to determine comparative study of lake and ground water. The study found that most of the lakes were polluted and this had an impact on surrounding ground water.

• Sleep Medicine and Psychophysiology
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• v.24 no.1
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• pp.5-11
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• 2017

The use of alcohol is associated with the development and worsening of sleep disorder. Alcohol is generally known to have a sedative effect, but it has an arousal or sedative effect depending on the timing and drinking dose and directly affects REM sleep physiology. Alcohol acts on the central nervous system (CNS) to interfere with the sleep-wake cycle and to affect sleep-related hormone secretion. In addition, the ingestion of alcohol pre-sleep is associated with deterioration and development of sleep related breathing disorders (SBD). The increase in resistance of the upper respiratory tract and the decrease in sensitivity of the CNS respiratory center and the respiratory muscles are major mechanisms of alcohol-induced SBD, and result in snoring or apnea in healthy men or aggravating apnea in patients with OSA. Sleep-related restless leg syndrome and circadian rhythm disorders are common in alcohol use disorder patients. This review provides an assessment of scientific studies that investigated on the impact of alcohol ingestion on nocturnal sleep physiology and sleep disorders.

• Journal of Korean Society on Water Environment
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• v.24 no.2
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• pp.247-259
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• 2008

The utilization of a variety of hazard chemicals bears risks to human health and ecosystem. The increasing usage of various chemicals indicates the greater emission of those chemicals to water system, and the subsequent deterioration of water quality. Water system is vulnerable to many pollutants, however, there are limitations of managing a range of hazard chemicals based on insufficient legal foundations. Therefore it is needed to select hazard chemicals that can be potentially discharged into water system, and subsequently to classify a wide range of existing chemicals for better management of those chemicals. In this study, the 259 candidate chemicals of concern were selected from the lists of the toxic released inventory chemicals (148), hazard concern candidate chemicals (106), and wastewater effluent standard candidate chemicals (116). We suggested the category 1, 2, 3 and 4 of hazard chemicals potentially discharged into water system. The assessment factors considered for the classification were hazard potential, persistence and emission to water body. This work was conducted as a part of the project entitled 'Development of integrated methodology for evaluation of water environment', and the results were used to develop the monitoring lists of hazard chemicals in four major rivers in Korea.

• Journal of Chest Surgery
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• v.51 no.5
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• pp.328-332
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• 2018

Background: Extracorporeal life support (ECLS) can be applied in brain-dead donors for organ perfusion before donation, thereby expanding the donor pool. The aim of this study was to examine the benefits and early clinical outcomes of ECLS for organ preservation. Methods: Between June 2012 and April 2017, 9 patients received ECLS with therapeutic intent or for organ preservation. The following data were collected: demographics, purpose and duration of ECLS, cause of death, dose of vasoactive drugs, and need for temporary dialysis before organ retrieval. The early clinical outcomes of recipients were studied, as well as survival and graft function at 1 month. Results: ECLS was initiated for extracorporeal cardiopulmonary resuscitation in 5 patients. The other patients needed ECLS due to hemodynamic deterioration during the assessment of brain death. We successfully retrieved 18 kidneys, 7 livers, and 1 heart from 9 donors. All organs were transplanted and none were discarded. Only 1 case of delayed kidney graft function was noted, and all 26 recipients were discharged without any significant complications. Conclusion: The benefits of protecting the vital organs of donors is significant, and ECLS for organ preservation can be widely used in the transplantation field.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.192-196
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• 2010

Due to a development of a modem technology as Power Line Communication(PLC) over 200 Mbps, the high-speed multi-media data trasmission could be currently possible. The strength of the PLC has no more additional wiring work. PLC has also possible to high quality data transmission with currently electrical cable. It has a various strong point campare with existing wire and wireless communication technologies. In This paper we develop a high quality media transmitter-receiver based on merging the HomePlug AV, which is 200 Mbps class PLC technology and HDMI Interface technology. The video function was used for the VEDEO TEST GENERATOR in order to a property valuation. Smart Live 6 software were used for the assessment of audio property. As the result of measurement of the HD class images by capturing from the receiver of the PLC, the quality of images couldn't be confirm any deterioration, which has compared with original reflections. In case of audio part as the result of confirmation of the Phase, Magnitude, it has been confirmed that over 90% of nomal transmition and receiving of acoustic signal. It can be possible to have HD class Media service through the PLC.

• Earthquakes and Structures
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• v.4 no.2
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• pp.157-179
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• 2013

Vulnerability studies on the existing building stock require that a large number of buildings is analyzed to obtain statistically significant evaluations of the seismic performance. Therefore, analytical evaluation methods need to be based on simplified methodologies of analysis which can afford the treatment of a large building population with a reasonable computational effort. Simplified Pushover-Based Earthquake Loss Assessment approach (SP-BELA), where a simplified methodology to identify the structural capacity of the building through the definition of a pushover curve is adopted, was developed on these bases. Main objective of the research work presented in this paper is to validate the simplified methodology implemented in SP-BELA against the results of more sophisticated nonlinear dynamic analyses (NLDAs). The comparison is performed for RC buildings designed only to vertical loads, representative of the "as built" in Italy and in Mediterranean countries with a building stock very similar to the Italian one. In NLDAs the non linear and degrading behaviour, typical of the structures under consideration when subjected to high seismic loads, is evaluated using models able to capture, with adequate accuracy, the non linear behaviour of RC structural elements taking into account stiffness degradation, strength deterioration, and pinching effect. Results show when simplified analyses are in good agreement with NLDAs. As a consequence, unsatisfactory results from simplified analysis are pointed out to address their current applicability limits.

• Computers and Concrete
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• v.19 no.1
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• pp.111-120
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• 2017

This study aimed to design the accelerated life testing (ALT) of concrete, which stimulating the special natural environment maximumly. Its evaluation indexes, such as dynamic elastic modulus, mass and ultrasonic velocity were measured, and the variation of relative mass and relative dynamic elastic modulus of concrete were studied. Meanwhile, the microanalysis method was used. Moreover, an exploratory application of the stochastic approach, the Weibull distribution and the lognormal distribution, were made to assess the durability of concrete structures. The results show that the ALT for simulating natural environment is more close to the service process of concrete structure under actual conditions; The relative dynamic elastic modulus can be used as the dominant durability evaluation parameters, because it is more sensitive to the environmental factors compared with the relative quality evaluation parameters; In the course of the concrete deterioration, the destruction of the salt freezing cycle is the dominant factor, supplemented by other factors; Both of those two stochastic approaches can be used to evaluate the reliability of concrete specimens under the condition of ALT; By comparison, The lognormal distribution method is better to describe the reliability process.