• Journal of the Korean Geotechnical Society
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• v.32 no.6
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• pp.41-48
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• 2016

This study presents the correlations between quantified particle shape parameters and internal friction angles for nine sand specimens including six natural sands and three crushed sands. Specimens are subjected to 3D X-ray computed tomographic imaging and their particles are segmented through the aid of image processing techniques. Shapes of segmented particles are then quantified through two shape parameters such as sphericity and elongation. The direct shear apparatus enables us to measure peak and critical state friction angles of sand specimens of distinct relative densities. The gathered data show that decreasing sphericity and increasing elongation cause increases in peak and critical state friction angle with similar gradients.

• Wind and Structures
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• v.27 no.3
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• pp.163-173
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• 2018

The design wind pressure for low-rise buildings in the ASCE 7-10 is defined by procedures that are categorized into the Main Wind Force-Resisting System (MWFRS) and the Components and Cladding (C&C). Some of these procedures were originally developed based on steel portal frames of industrial buildings, while the residential structures are a completely different structural system, most of which are designed as low-rise light-frame wood constructions. The purpose of this study is to discuss the rationality (or irrationality) of the extension of the wind loads calculated by the ASCE 7-10 to the light-frame wood residential buildings that represent the most vulnerable structures under extreme wind conditions. To serve this purpose, the same approach as used in the development of Chapter 28 of the ASCE 7-10 that envelops peak responses is adopted in the present study. Database-assisted design (DAD) methodology is used by applying the dynamic wind loads from Louisiana State University (LSU) database on a typical residential building model to assess the applicability of the standard by comparing the induced responses. Rather than the postulated critical member demands on the industrial building such as the bending moments at the knee, the maximum values at the critical points for wood frame buildings under wind loads are used as indicators for the comparison. Then, the critical members are identified through these indicators in terms of the displacement or the uplift force at connections and roof envelope. As a result, some situations for each of the ASCE 7 procedures yielding unconservative wind loads on the typical low-rise residential building are identified.

• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.145-154
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• 2022

Based on the obtained results of the study, the most problematic issues and legal conflicts are identified, which are related to the ratio of norms of domestic and foreign legislation, taking into account the requirements of the Constitution of Ukraine and the provisions of the Law of Ukraine "On international agreements". Along with this, it is stated in this scientific article that there are a number of provisions and examples of positive practice on the specified topic abroad and in international legal acts today, which should be used by Ukraine both in improving legislation on the issues of banking activity and in increasing the level of criminal legal protection of relevant critical infrastructure facilities, especially those that are substantively related to prevention and counteraction of activity, with regard to the legalization (laundering) of criminally obtained funds, financing of terrorism and the financing of the proliferation of weapons of mass destruction, which is quite relevant for our state, given the military conflict that is taking place on its territory in the Donbass. Again, in the same context, the need for more active cooperation between Ukraine and the FATF (international body developing a policy to combat money laundering) has been proven.

• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.679-691
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• 2023

Many codes allow designers to use the bending moment diagram computed by elastic analysis and modify it by a certain amount of moment redistribution (MR) to account for plastic behaviour of continuous beams. However, several researchers indicated that the MR at the ultimate limit state (𝛽_u) for some beams deviate significantly from the specified values of various codes. This paper examines the applicability of the provisions on 𝛽_u in ACI 318-19 and Eurocode 2 through numerical investigations and comprehensively explores the influencing factors. The results show that some parameters not considered in those codes influence 𝛽_u to a certain extent, where the ratio of tensile reinforcement ratio at intermediate support to tensile reinforcement ratio at midspan (𝜌_s1/𝜌_s2) and load type are crucial parameters to consider. The specific combination of these two parameters may make the codes overestimate or significantly underestimate the 𝛽_u. On the other hand, the yield state of both critical sections is found to have an important influence on the influence degree of each parameter on 𝛽_u. The yield conditions are investigated, and an empirical judgment equation is proposed. In addition, the influence laws of the critical parameters on 𝛽_u have been further proved by theoretical derivation. Finally, due to 𝜀_t is found to have a better linear correlation with 𝛽_u than x_u/d, equations as a function of 𝜀_t for predicting the 𝛽_u of continuous beams under the two loads are proposed, respectively.

• Journal of the Korean Society of Safety
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• v.39 no.3
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• pp.7-13
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• 2024

This study examines the physical characteristics of self-regulating heating cables caused by increased temperature and fire risk due to local degradation. A thermo hygrostat system, a convection dryer, a digital multimeter (Agilent 34465 A), NI DAQ, and the LabVIEW program were used to assess the physical properties in response to temperature fluctuations. As the temperature increases, the resistance of the self-regulating heating cable increases; however, when the critical point is exceeded, the resistance sharply decreases. A problem arises when the resistance value cannot return to its original state even though the temperature is lowered to the initial state. Moreover, when the ambient temperature rises while power is applied, the resistance value initially increases, and the flowing current decreases, maintaining a constant state. However, when the critical temperature is exceeded, the flowing current increases because of a rapid decrease in the resistance value, progressing to ignition. When the resistance value decreases because of the deterioration of one local area, the total resistance value becomes less than the initial resistance value. Therefore, the flowing current increases and an ignition problem occurs at one location where deterioration occurs. Despite the sustained flames and arcs resulting from the changes in the overall physical properties of the self-regulating heating cable and resistance variations due to local decline, the fire continued as the flowing current was lower than the operating current of the circuit breaker, failing to cut the power. In the case of self-regulating heating cables and heating wires, which are the leading causes of fires in winter, efforts are needed to ensure the need for periodic maintenance and the use of KS-certified products.

• ETRI Journal
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• v.15 no.3
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• pp.1-26
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• 1994

Simulated annealing is an attractive, but expensive, heuristic method for approximating the solution to combinatorial optimization problems. Attempts to parallel simulated annealing, particularly on distributed memory multicomputers, are hampered by the algorithm's requirement of a globally consistent system state. In a multicomputer, maintaining the global state S involves explicit message traffic and is a critical performance bottleneck. To mitigate this bottleneck, it becomes necessary to amortize the overhead of these state updates over as many parallel state changes as possible. By using this technique, errors in the actual cost C(S) of a particular state S will be introduced into the annealing process. This paper places analytically derived bounds on this error in order to assure convergence to the correct optimal result. The resulting parallel simulated annealing algorithm dynamically changes the frequency of global updates as a function of the annealing control parameter, i.e. temperature. Implementation results on an Intel iPSC/2 are reported.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.60-65
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• 2003

An effective modeling and simulation scheme of a resistive type Superconducting fault Current Limiter (SFCL) using PSCAD/EMTDC is proposed in this paper. In case of High Temperature Superconducting (HTS) resistive type fault current limiter current limiting is implemented by the ultra-fast transition characteristics from the superconducting (non-resistive) state to the normal (resistive) state by overstepping the critical current density. The states can generally be divided into three sub-states: the superconducting state the quench state and the recovery state respectively. In order to provide alternative application schemes of a resistive type SFCL, an effective modeling and simulation method of the SFCL is necessary. For that purpose, in this study, an actual experiment based component model is developed and applied for the simulation of the real resistive type SFCL using PSCAD/EMTDC. The proposed simulation scheme can be implemented to the grid system readily under various system conditions including sort of faults and the system capacity as well. The simulation results demonstrate the effectiveness of the proposed model and simulation scheme.

• Journal of Industrial Technology
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• v.42 no.1
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• pp.19-27
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• 2022

This review will discuss the effort to understand the interfacial reactions at the anode and cathode sides of all-solid-state batteries. Antiperovskite solid electrolytes have received increasing attention due to their low melting points and anion tunability which allow controlling microstructure and crystallographic structures of this material system. Antiperovskite solid electrolytes pave the way for the understanding relationship between critical current density and mechanical properties of solid electrolytes. Microstructure engineering of cathode materials has been introduced to mitigate the volume change of cathode materials in solid-state batteries. The hollow microstructure coupled with a robust outer oxide layer effectively mitigates both volume change and stress level of cathode materials induced by lithium insertion and extraction, thus improving the structural stability of the cathode and outer oxide layer, which results in stable cycling performance of all-solid-state batteries.

• The Korean Journal of Food & Health Convergence
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• v.5 no.1
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• pp.1-11
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• 2019

Smoking has become one of the public health harzard affecting the world. In the UK, smoking is responsible for around one in five deaths. The illnesses caused by smoking extend beyond the well-reported links with cancer, heart disease and respiratory illnesses. Hence the research to determine the awareness of the predisposing factor to smoking among adults in sokoto metropolis. A cross-sectional form of descriptive survey research design was used for this study. This is because descriptive studies are used when the characteristics of a population are either unknown or partially known (Hennekens & Buring, 2007), and it was used by Ganley and Rosario (2013) in a related research this justified the use of similar design in a study of similar nature.Two hundred and seventy returned questionnaire was collected, analyzed using descriptive statistic of frequency count, normative percentage and grand mean; as well as inferential statistics of chi-square (${\chi}^2$). The level of significant was fixed at 0.05. Appropriate degrees of freedom were worked out. There was statistical significant influence or relationship with marital status on the predisposing factors of smoking chi-square of 19716.516 greater than the critical value 43.77297at df 30 p<0.05. There were statistical significance chi-square =27468.348 which is greater than the critical value 43.77297 at df= 30. These show that there is a relationship on gender awareness of predisposing factors to smoking rejecting the null hypotheses. The respondents across different lever/year higher institution shows that the awareness of predisposing factors of smoking there were a statistical significance difference chi-square =7168.429 (df=88) greater than critical value 102.342 rejecting the null hypotheses. There is consistent evidence that links exposure to depictions of smoking in movies and initiation of smoking in young people. Over the years television shows and films have effectively built up associations between smoking and glamour, sex and risk-taking. Social learning theory describes how we learn by example from others. We are strongly influenced by our parents, and other people we look up to, such as peers, actors and pop stars. This can lead us to emulate their behaviour and try smoking.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.2
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• pp.77-95
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• 2014

The purpose of this study is to analyze ego state types of teacher librarians by using egogram of the Transactional Analysis. It is the ideal ego state types for teachers that NP (Nurturing Parent), A (Adult) and FC (Free Child) are much higher than CP (Critical Parent) and AC (Adapted Child). But the teacher librarians are under higher CP and AC rather than A and FC. It means that the teacher librarians consider their values and belief as right things. Also it seams that they have not a conciliatory attitude but a hardened attitude that emphasize rules and standards. These ego state may be obstacle to their instructors role under the constructivist learning environment highlighting self directed learning of students. So, in the training course for the teacher librarians, informational and educational service course and development programs of education contents and instructional materials should be reinforced in order to strengthen their teaching competence and partnerships.