• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.11a
• /
• pp.187-188
• /
• 2019

The supply of apartments has continuously increased, and the housing supply rate has exceeded 100 percent and the demands and standards of tenants have also been raised as technology has developed. This has led to the conflict and caused social and economic losses. In this study, the case investigation and research methods of the prior research are analyzed as the basis for identifying the defects cases of causes and influences occurring in the apartment building. To analyze various studies, we divided the prior research into the defect management process and the study on the type of defects and countermeasures, and investigated the features and limitations. Future research will be conducted on apartment buildings within 10 years of completion among conglomerate's nationwide apartments to compensate for the limitations of prior research. In addition, AHP static method and relational chart will be used to identify the relationship between the type of defect and the cause and the importance of the influencing factors.

• Geomechanics and Engineering
• /
• v.9 no.6
• /
• pp.729-742
• /
• 2015

The aim of the present work was the study of instability in a loose sand from Les Dunes beach in Ain Beninan, Algeria, where the Boumerdes earthquake occurred in 2003. This earthquake caused significant structural damages and claimed the lives of many people. Damages caused to infrastructures were strongly related to phenomena of liquefaction. The study was based on the results of two drained and six undrained triaxial tests over a local sand collected in a region where liquefaction occurred. All the tests hereby analyzed followed compression stress-paths in monotonic conditions and the specimens were isotropically consolidated, since the objective was to study the instability due to static loading as part of a more general project, which also included cyclic studies. The instability was modeled with the second-order work increment criterion. The definition of the instability line for Les Dunes sand and its relation with yield surfaces allowed the identification of the region of potential instability and helped in the evaluation of the susceptibility of soils to liquefy under undrained conditions and its modeling. The dilatancy rate was studied in the points where instability began. Some mixed tests were also simulated, starting with drained conditions and then changing to undrained conditions at different time steps.

• Journal of the Korean Magnetics Society
• /
• v.5 no.5
• /
• pp.528-532
• /
• 1995

Ferromagnetic resonance experiments have been used to investigate the magnetic properties of amorphous $Co_{89.5}Zr_{10.5}$ thin films deposited by DC magnetron sputtering method. In the thickness range from $350\;{\AA}$ to $3,200\;{\AA}$, measurements were carried out in a static magnetic field perpendicular and parallel to the film plane and in a conventional 9.44 GHz spectrometer at room temperature. The ferromagnetic resonance spectra by the field perpendicular to the film plane showed standing spin wave. The spacing and the relative intensities between the various spin wave resonance peaks are analysed considering surface magnetic anisotropy. The surface magnetic anisotropy constant ($K_{so},\;K_{sd}$) of amorphous $Co_{89.5}Zr_{10.5}$ thin films are $0.02\;erg/\textrm{cm}^2$ and $0.55\;erg/\textrm{cm}^2$ respectively regardless of the film thickness except for $3,200\;{\AA}$ film. In case of $3,200\;{\AA}$ these values are $0.46\;erg/\textrm{cm}^2$ and $0.55\;erg/\textrm{cm}^2$ respectively.

• Nuclear Engineering and Technology
• /
• v.37 no.4
• /
• pp.391-394
• /
• 2005

N-(3-bromo-2,4,6-trimethylacetanilide)iminodiacetic acid (BrTIDA) was synthesized using nitrilotriacetic anhydride prepared in situ, and lyophilized vials were prepared which contained 20 mg of BrTIDA and 0.4 mg of $SnCl_2$. To evaluate the clinical efficacy of the in-house prepared lyophilized kit, a technetium-99m complex of BrTIDA was prepared; its in vivo pharmacokinetic behavior was evaluated via animal studies to assess the hepatocytic function and the functional status of the cystic duct and the gallbladder. Serial static image scans of rabbits and the biodistribution in mice injected with $^{99m}Tc-BrTIDA$ revealed that none of the tissues except for the hepatobiliary system showed radioactivity concentrations, and a rapid clearance from the organs was observed. In conclusion, a lyophilized kit and its prepared $^{99m}Tc-BrTIDA$ can be applied as a hepatobiliary imaging agent for the evaluation of the functional status of the hepatocytes and the patency of the biliary duct.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.5
• /
• pp.639-648
• /
• 2021

The study aims to examine the role of financial risk management in predicting the financial performance of commercial banks in Pakistan over the period of 2006-2017. For this purpose, risk management is measured through credit risk, interest rate risk, and liquidity risk, while financial performance is measured through ROA, ROE, and ROI. For this purpose, the dynamic panel model and two step GMM panel estimators are used to test the hypothesis empirically. The annual secondary data has been taken from the published financial reports of commercial banks of Pakistan. The results show that financial risk management significantly decreases the financial performance of commercial banks in Pakistan. Overall, the results are conclusive across the alternative measures of financial risk management in predicting the financial performance of the banking sector in Pakistan. The study suggested that managers should adopt risk management and risk hedging strategies to manage commercial banks' financial risks in Pakistan. They should hold extra cash while using the trade credit facilities. Previous studies mostly used a static model, but this study used a dynamic panel model. This study is among the first that focused on the various factors affecting the banks' performance in Pakistan.

• International Area Studies Review
• /
• v.13 no.2
• /
• pp.41-65
• /
• 2009

This study based on international input-output model shows various static analyses of the effects by estimating the intermediary goods' trade volume that affects the industrial production. When concluding tariff removal between Korea and Japan, as intermediary goods import increases, Korea's trade balance deficit with Japan is expected to grow more than before. However, Korea's increase in export to the world is the largest benefit Korea can earn from tariff removal between the two countries.

• Steel and Composite Structures
• /
• v.29 no.5
• /
• pp.669-680
• /
• 2018

The rapidly decreasing natural resources and the global variation of the climate push us to find intelligent and efficient structural systems to provide more people with fewer resources. This paper proposed a kinematic cable-strut system to realize sustainable structures in responding to changing environmental conditions. At first, the concept of the kinematic system based on crystal-cell pyramid (CP) cable-strut unit was given. Then the deployment of the structure was studied experimentally. After that, the static behaviors in the fully deployed state under the symmetric and asymmetric load cases were investigated. Moreover, the effects of thermal loading and the initial prestress distribution were also discussed. Comparative studies between the proposed structure and other deployable cable-strut system under three times of design load cases were carried out. Finally, the robustness of the system was studied by removal of one passive cable at one time.

• Computers and Concrete
• /
• v.22 no.6
• /
• pp.527-538
• /
• 2018

Buckling of longitudinal bars is a brittle failure mechanism, often recorded in reinforced concrete (RC) structures after an earthquake. Studies in the literature highlights that it often occurs when steel is in the post elastic range, by inducing a modification of the engineered stress-strain law of steel in compression. A proper evaluation of this effect is of fundamental importance for correctly evaluating capacity and ductility of structures. Significant errors can be obtained in terms of ultimate bending moment and curvature ductility of an RC section if these effects are not accounted, as well as incorrect evaluations are achieved by non-linear static analyses. This paper presents a numerical investigation aiming to evaluate the engineered stress-strain law of reinforcing steel in compression, including second order effects. Non-linear FE analyses are performed under the assumption of local buckling. A role of key parameters is evaluated, making difference between steel with strain hardening or with perfectly plastic behaviour. Comparisons with experimental data available in the literature confirm the accuracy of the achieved results and make it possible to formulate recommendations for design purposes. Finally, comparisons are made with analytical formulations available in the literature and based on obtained results, a modification of the stress-strain law model of Dhakal and Maekawa (2002) is proposed for fitting the numerical predictions.

• Journal of Korean Association for Spatial Structures
• /
• v.18 no.4
• /
• pp.69-80
• /
• 2018

In this study, an algorithm applying deep learning to the truss structures was proposed. Deep learning is a method of raising the accuracy of machine learning by creating a neural networks in a computer. Neural networks consist of input layers, hidden layers and output layers. Numerous studies have focused on the introduction of neural networks and performed under limited examples and conditions, but this study focused on two- and three-dimensional truss structures to prove the effectiveness of algorithms. and the training phase was divided into training model based on the dataset size and epochs. At these case, a specific data value was selected and the error rate was shown by comparing the actual data value with the predicted value, and the error rate decreases as the data set and the number of hidden layers increases. In consequence, it showed that it is possible to predict the result quickly and accurately without using a numerical analysis program when applying the deep learning technique to the field of structural analysis.

• Corrosion Science and Technology
• /
• v.17 no.6
• /
• pp.310-316
• /
• 2018

The effect of passive film on corrosion of metals and alloys in a static corrosive environment has been studied by many researchers and is well known, however few studies have been conducted on the electrochemical measurement of metals and alloys during cavitation corrosion conditions, and there are no test standards for electrochemical measurements 'During cavitation' conditions. This study used commercially additive manufactured(AM) pure titanium in tests of anodic polarization, corrosion potential measurements, AC impedance measurements, and repassivation. Tests were performed in 3.5% NaCl solution under three conditions, 'No cavitation', 'After cavitation', and 'During cavitation' condition. When cavitation corrosion occurred, the passive current density was greatly increased, the corrosion potential largely lowered, and the passive film revealed a small polarization resistance. The current fluctuation by the passivation and repassivation phenomena was measured first, and this behavior was repeatedly generated at a very high speed. The electrochemical corrosion mechanism that occurred during cavitation corrosion was based on result of the electrochemical properties 'No cavitation', 'After cavitation', and 'During cavitation' conditions.