• International Journal of High-Rise Buildings
• /
• v.4 no.3
• /
• pp.219-226
• /
• 2015

By the end of 2014, the number of completed and under-construction supertall buildings above 250 meters in China reached 90 and 129, respectively. China has become one of the centers of supertall buildings in the world. Supertall buildings in China are getting taller, more slender, and more complex. The structural design of these buildings focuses on the efficiency of lateral resisting systems and the application of energy dissipation. Furthermore, the research, design, and construction of high-performance materials, pile foundations, and mega-members have made a lot of progress. Meanwhile, more and more challenges are presented, such as the improvement of structural system efficiency, the further understanding of failure models, the definition of design criteria, the application of high-performance materials, and construction monitoring. Thus, local structural engineers are playing a more important role in the design of supertall buildings.

• Computers and Concrete
• /
• v.16 no.2
• /
• pp.209-222
• /
• 2015

This paper presents results of biaxial compressive tests and strength criterion on two replacement percentages of recycled coarse aggregate (RPRCA) by mass for plain structural recycled aggregate concrete (RAC) at all kinds of stress ratios. The failure mode characteristic of specimens and the direction of the cracks were observed and described. The two principally static strengths in the corresponding stress state were measured. The influence of the stress ratios on the biaxial strengths of RAC was also analyzed. The experimental results showed that the ratios of the biaxial compressive strength ${\sigma}_{3f}$ to the corresponding uniaxial compressive strength $f_c$ for the two RAC are higher than that of the conventional concrete (CC), and dependent on the replacement percentages of recycled coarse aggregate, stress states and stress ratios; however, the differences of tensile-compressive ratios for the two RAC and CC are smaller. On this basis, a new failure criterion with the stress ratios is proposed for plain RAC under biaxial compressive stress states. It provides the experimental and theoretical foundations for strength analysis of RAC structures subject to complex loads.

• Advances in aircraft and spacecraft science
• /
• v.9 no.1
• /
• pp.59-68
• /
• 2022

The physical and mathematical foundations of the heat-shielding composite materials functioning under the conditions of aerodynamic heating of aircraft, as well as under the conditions of the point effect of high-energy radiation are considered. The problem of deformation of a thin shallow shell under the action of a local temperature field is approximately solved. Such problems arise, for example, in the case of local destruction of heat-protective coatings of aircraft shells. Then the aerodynamic heating acts directly on the load-bearing shell of the structure. Its destruction inevitably leads to the death of the entire aircraft. A methodology has been developed for the numerical solution of the entire complex problem on the basis of economical absolutely stable numerical methods. Multiple results of numerical simulation of the thermal state of the locally heated shallow shell under conditions of its thermal destruction at high temperatures have been obtained.

• Geomechanics and Engineering
• /
• v.28 no.1
• /
• pp.89-105
• /
• 2022

The behavior of the soil subgrade is complex and irregular against loads. When modeling, the soil is often replaced by a more straightforward system called a subgrade model. The Winkler method of linear elastic springs is a popular method of soil modeling in which the spring constant shows the modulus of subgrade reaction. In this research, the factors affecting the distribution of the modulus of subgrade reaction of elastoplastic subgrades are examined. For this purpose, critical theories about the modulus of subgrade reaction were examined. A square raft foundation on a sandy soil subgrade with was analyzed at different internal friction angles and Young's modulus values using ABAQUS software. To accurately model the actual soil behavior, the elastic, perfectly plastic constitutive model was applied to investigate a foundation on discrete springs. In order to increase the accuracy of soil modeling, equations have been proposed for the distribution of the subgrade reaction modulus. The constitutive model of the springs is elastic, perfectly plastic. It was observed that the modulus of subgrade reaction under an elastic load decreased when moving from the corner to the center of the foundation. For the ultimate load, the modulus of subgrade reaction increased as it moved from the corner to the center of the foundation.

• Educational Technology International
• /
• v.6 no.2
• /
• pp.43-58
• /
• 2005

The purpose of this study was to investigate the impact of organizational learning culture on job satisfaction and organizational commitment. Two streams of scholarly work have provided the theoretical foundations for this study. The first stream comes from the literature on learning organization. The second stream of the theoretical foundation comes from an extensive literature on attitude-intention-behavior relationships. In addition, this study was tested three alternative models. Alternative model 1 employed job satisfaction as the mediating commitments variable between learning culture and organizational commitment. Alternative model 2 used organizational commitment as the mediating variable between learning culture and job satisfaction. Finally, alternative model 3 specified a direct impact of learning culture on both job satisfaction and organizational commitment, and reciprocal linkages between these two variables. The results of this study support the hypothesized relations among an organization's learning culture, job satisfaction, and organizational commitment. The findings of this study are various congruent with a widely accepted hypothesis that job satisfaction serves as an appraisal function in evaluating various work environments and determining emotional responses such as organizational commitment. Organizational learning culture is one of the important factors that organizations cannot overlook. Therefore, the findings of this study provide a new direction for researchers seeking to explain the complex relations among these central organizational variables.

• Steel and Composite Structures
• /
• v.53 no.4
• /
• pp.377-399
• /
• 2024

Accurately predicting the bearing capacity of steel and concrete piles is a critical factor in the design and safety of deep foundations. This study presents a novel application of hybrid machine learning models, specifically Invasive Weed Optimization with Multilayer Perceptron (IWOMLP) and Harris Hawks Optimization with Multilayer Perceptron (HHOMLP), for enhancing the prediction of pile bearing capacity. These hybrid models integrate evolutionary optimization algorithms with neural networks, aiming to improve prediction accuracy by addressing the nonlinearities and complexities in pile-soil interaction. The study compares the performance of IWOMLP and HHOMLP against conventional machine learning methods such as Simple Linear Regression, Gaussian Processes, Random Forest, and others. The training and testing phases evaluate the models based on various error metrics, including R², RMSE, MAE, and additional advanced metrics. The key innovation in this research lies in combining optimization techniques with neural networks, which significantly enhances the model's ability to predict complex geotechnical properties. The primary goal of this work is to develop a reliable, data-driven approach for accurate pile capacity prediction, providing a more precise tool for geotechnical engineers to improve decision-making in foundation design. Results indicate that the hybrid models, particularly IWOMLP, outperform traditional approaches, achieving higher R² and lower RMSE values. This research demonstrates the potential of hybrid models to advance geotechnical engineering practices by delivering more accurate and reliable predictions.

• Korean Institute of Interior Design Journal
• /
• v.14 no.1
• /
• pp.168-176
• /
• 2005

As the pluralistic value in which various cultures and trends exist develops the world at large, development of interior design is required to examine consumers by group. This requirement purports to set up a strategic model of operating interior design organizations under cross-cultural (past and present) enviroment, not to express new researches of interior design following the direction of the developed media service. Based on the educational and complex cultural approach to design matters - the key issue in solving the cross-cultural design matters, this paper has suggested the structure of semi-centralized design process and the system for finding out consumers' trends under the new media-based cultural design environment. This study presents some expected effects. First, it will be able to enhance the consumer-oriented design mind by providing the information on the interior design system and design trend. Through analyzing the lifestyle in the 21st century and providing the relevant information, it will lead irrlprovement in living environment. And further, by using the program of searching consumers' new preference, the system of grasping consumers' propensity and making decisions will be materialized. Secondly, based on the background database of forecasted consumers' trends, marketing strategies can be established. Thirdly, through the better technology of designing living environment, efficiency will be increased and the economic foundations through use of new database will be constructed. Fourth, systematic interior design can be developed. Strategic correspondence to consumers' desires and reinforcement of competitiveness will become possible with development of database. By encouraging consumers' participation under digital environment, their trends can be forecasted, and by efficiently using information and new technology, resources can be saved and further, additional costs for promotion and sales will be reduced.

• Asia pacific journal of information systems
• /
• v.21 no.3
• /
• pp.19-49
• /
• 2011

The multifarious array of benefits to the e-Government systems research, from evaluative frameworks and conceptual models to guidelines for initiatives, adoption, and assimilation, evidences the requirement, both from the researcher's and the practitioner's standpoint, of sound theoretical foundations that can be applied directly in practice. Grounded upon structuration theory, this paper proposes a framework for e-Government systems assimilation through the structuration of its organizational factors. Upon this proposition, we map the factors of e-Government systems assimilation with the organizational meta-structures of signification, domination and legitimization. The framework is then tested for the case of one particular e-Government systems of Korean government. The juxtaposition of the theoretical position and the practical findings leads us to isolate the organizational, technological, and inter-organizational factors that shape the meta-structures for the assimilation of e-Government systems. This framework offers interesting possibilities to researchers in exploring the relationships and insights into the complex interactions that shape the relationships among government, people and technology. Thus, the paper's contribution lies on three axes: first, the furthering of a theoretical perspective of e-Government systems assimilation; second, a detailed exposition of the structuration theory and an illustration of its application to the issues of e-Government systems assimilation in the organizational context; and finally, developed framework through the isolation of a usable set of theoretically grounded factors affecting e-Government systems assimilation that can be applied in future research and practice.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.60 no.4
• /
• pp.15-25
• /
• 2018

The accident risk at the construction workplace associated with agricultural engineering is comparatively higher than those of other fields due mainly to its complex work types and processes. Agricultural engineering deals with a variety of agricultural infrastructures from irrigation and drainage facilities to giant-scale coastal reclamation land infrastructures. The characteristics that most agricultural projects have conducted on a small-scale even worsen the situation drawing low attentions to risk management. Therefore, systematical risk assessment that focuses on details of agricultural construction work process is required in order to enhance safety management capacity and to prevent repetitive accidents ultimately. This study aims to categorize construction work types and processes of agricultural construction works, and to quantitatively assess the accident risk of them based on accident analysis. Regarding classification of construction works, actual 827 accident cases were thoroughly reviewed and coded by their construction site, facility and work type, project scale and so on. Most accidents (71.8 % of total cases) occurred in small-scale construction workplaces with less than 5 billion Korean won project budget. And those accidents related to agricultural infrastructure project (37.4%) and agricultural water development project (22.4%). In terms of work types, accidents frequently took place in form-work followed by pipe installation work, steel bar work and concrete work. The potential risks were compared with actual outbreak of accidents based on Analytic Hierarchy Process (AHP). The results show that the potential conditions of accident expected to be took place is somewhat different from the actual conditions where accidents actually happened. This implicates that risk management manuals or education needs to be adjusted by reflecting unexpected circumstances. Overall, this study is meaningful in that the results could be foundations as to strengthen risk management capacity for agricultural engineering projects.

• Journal of the Korean Geotechnical Society
• /
• v.18 no.3
• /
• pp.43-50
• /
• 2002

This paper describes a simplified numerical procedure for analyzing the response of bridge pier foundations due to riverbed scouring. A computationally efficient algorithm to analyze the behavior of a pile group is proposed by considering soil-pile, pile-cap, and pile-fluid interactions. The complex phenomenon of the pile-soil interaction is modeled by discrete nonlinear soil springs (p-y, t-z and q-z curves). The pile-cap interaction is considered by geometric configuration of the piles in a group and connectivity conditions between piles and the cap. The pile-fluid interaction is incorporated into the procedure by reducing the stiffness of the soil-pile reactions as a result of nonlinearity and degradation of the soil stiffness with river bridge scouring. Through the numerical study, it is shown that the maximum bending moment increases with increasing scour depth. Thus it is desirable to check the stability elf pile groups based on soil-pile and pile-cap interactions by considering scouring depth in the riverbed.