• Journal of Korea Technology Innovation Society
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• v.2 no.2
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• pp.169-186
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• 1999

This study empirically investigates innovative behaviors of the firm. In so doing, a Probit was employed and estimated. We used the raw data of the "corporate innovation survey"(CIS), which, in consent with OECD efforts, is regularly undertaken by the Science and Technology Policy Institute(SIEPI). The data set includes more than 3400 firms in the manufacturing sector. Three types of innovation, i.e., new product, product improvement and process innovation, are studied, assuming that determinants of innovation are firm′s age. number of employees as the size of firm, ratio of foreign ownership and innovation costs. To investigate the relationship between firm′s innovation behavior and the size, we estimate the Probit including the quadratic term of the firm size. Empirical findings showed that the sign of the quadratic term of the firm size turned out to be negative. It means that the probability of firm's making innovation shows the inversed-U relationship with the firm size. Such an empirical result may have a significant implication for the industrial policy.

• Steel and Composite Structures
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• v.24 no.3
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• pp.383-391
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• 2017

The goal of this study is to investigate structural analysis and behaviors of an innovative aerial work platform truss frame whose ductility is improved by using high strength-steel UL-700. The present space truss frame can move or stop through tunnels for maintenance constructions by automatic facilities and workmanship within standardized limited building lines of tunnel. Most of all, this method overcomes problematic, which is to block cars during construction periods, seriously, of typical methods like as using truck and scaffolds for tunnel maintenance. According to evaluated appropriate design results of space truss frames of numerical examples by using a commercial MIDAS GEN program, it is verified that design parameters such as layered size, cross-sectional size, and steel material of the present space truss frame are determined to depend on characteristics such as lanes or shape of road tunnels.

• Structural Monitoring and Maintenance
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• v.5 no.2
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• pp.261-272
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• 2018

The commonly used TMD design method in the project assumes the TMD has pure linearity. However, in real engineering TMD will exhibit nonlinear behaviors. Without considering the nonlinearity of TMD, the control effect of the TMD that is designed by the linear design method, may be worse and even enlarge the structural response. In this paper, based on the previous study results of nonlinear TMD, the improved design method for engineering application is proposed. The linear design method and the improved design method are compared. Taking the best parameter obtained by the improved design method is less than or equal to 90% of that obtained by the original design method as the dividing line. The critical nonlinear coefficient, reaching which value the improved design method needs to be used, is given. Finally, numerical simulations on two engineering examples are conducted to proof the results.

• Research in Mathematical Education
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• v.15 no.2
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• pp.115-126
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• 2011

The aim of this study was to explore teachers' values about teaching mathematics in the classrooms which implemented Lesson Study and Open Approach as a teaching approach. The targeted group was 83 school teachers from 4 schools participating in a teacher professional development project. The data was gathered through teacher questionnaires, lesson observations and interviews. Data analysis is based on Bishop's (1988; 2003; 2007) and Komin's (1990) frameworks. The results from the implementation of Lesson Study and Open Approach in Thai classroom found the different of the roles and behaviors of teachers and students in classroom. The results revealed 3 kinds of values about teaching: Mathematical values, General educational values, Mathematics educational values and also found that most of the teachers valued problem solving as an innovative teaching approach as against traditional approaches they were familiar with.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.65-68
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• 2005

Social requirements to the civil and building structures have been changed in accordance with the social and economic progress. It is very important to develop the innovative structural materials and tecnology that the social requirements appropriately. Ductility of High Performance Fiber Reinforced cementitious Composites (HPFRCC), which exhibit strain hardening and multiple crackling characteristics under the uniaxial tensile stress are drastically improved. Because ductility in tensile test are very different according to specimen shapes, three types of the direct tensile test are performed. The tensile test are performed using the tensile test specimen, dummbell-shaped specimen, and cylinder specimen. As a result, tensile performance in HPFRCC is very good comparing to cylinder specimen because of direction characteristics of fibers. It is necessary to clarify the examination method of suiting to the usage.

• Steel and Composite Structures
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• v.24 no.4
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• pp.513-521
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• 2017

The goal of this study is to investigate structural analysis and behaviors of an innovative aerial work platform truss frame whose ductility is improved by using high strength-steel UL-700. The present space truss frame can move or stop through tunnels for maintenance constructions by automatic facilities and workmanship within standardized limited building lines of tunnel. Most of all, this method overcomes problematic, which is to block cars during construction periods, seriously, of typical methods like as using truck and scaffolds for tunnel maintenance. According to evaluated appropriate design results of space truss frames of numerical examples by using a commercial MIDAS GEN program, it is verified that design parameters such as layered size, cross-sectional size, and steel material of the present space truss frame are determined to depend on characteristics such as lanes or shape of road tunnels.

• Asia pacific journal of information systems
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• v.11 no.4
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• pp.1-25
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• 2001

Manufacturing firms face a paradigm shift from industrial systems driven by efficiency to post-industrial systems where success depends on a quick-response to customer demands for a variety of high-quality products. In essence, time is becoming a critical dimension for competition. New information technologies allow many firms to pursue time-based competitive strategies. The purpose of this research is to investigate the relationship among the types of information technology, behaviors of suppliers, the structures of new product development processes, and the competitiveness of the firms. The data for this study were collected from 96 Korean manufacturing firms that have implemented certain types of information technologies. Research results from LISREL analysis confirm that the competitiveness comes from product innovation capabilities and innovative product development process. But the linkage between the information technologies and the firms' competitiveness proves to be indirect. Suppliers, organizational culture related to IT, and some other factors also have indirect impact on the competitiveness. A summarized report of other findings is provided as well.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.3
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• pp.242-248
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• 2010

In this paper, Verification of the qualitatively identical relationships existing between simulation data and experimental results allowed for a new analysis procedure of a planetary gear set -- in an automatic transmission -- to be conducted. Tooth profiles were found to be crucial to the gear mesh forces of the planetary gear set. Based on Kahraman's Model, dynamic resonances of the planetary gear set were found to be out of operating range. Most importantly, a 2DPLANETARY FEM program, an innovative design tool for planetary gear sets, was utilized.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.33 no.12
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• pp.29-39
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• 2017

The building skins are important architectural elements in both functional and aesthetical aspects. This study focuses on developing a responsive facade with autonomous opening and closing behaviors in accordance with environmental conditions and user requirements for natural ventilation for the office building. The pneumatic ETFE panels are applied as the skin materials taking advantage of the efficiency of the inflatable skin of lightness, architectural performance and sustainable material properties. The biomimetic design methodology is taken for its innovative and visionary concept for the facade design. The interpretation of the building facade in analogy to natural organisms delivers functional and aesthetic characters. By exploring the structural movements of the plant pores, the facade control is developed to be autonomous by the parameter values. The facade opening and closing configurations are derived through parametric modeling and visualization programming. Through the application of this study, expected results are to improve user comfort and energy efficiency.

• Smart Structures and Systems
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• v.25 no.2
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• pp.241-254
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• 2020

Using confined shape memory alloy (SMA) bar or plate, this study proposes an innovative self-centering damper. The damper is essentially properly machined SMA core, i.e., bar or plate, that encased in buckling-restrained device. To prove the design concept, cyclic loading tests were carried out. According to the test results, the damper exhibited desired flag-shape hysteretic behaviors upon both tension and compression actions, although asymmetric behavior is noted. Based on the experimental data, the hysteretic parameters that interested by seismic applications, such as the strength, stiffness, equivalent damping ratio and recentering capacity, are quantified. Processed in the Matlab/Simulink environment, a preliminary evaluation of the seismic control effect for this damper was conducted. The proposed damper was placed at the first story of a multi-story frame and then the original and controlled structures were subjected to earthquake excitations. The numerical outcome indicated the damper is effective in controlling seismic deformation demands. Besides, a companion SMA damper which represents a popular type in previous studies is also introduced in the analysis to further reveal the seismic control characteristics of the newly proposed damper. In current case, it was found that although the current SMA damper shows asymmetric tension-compression behavior, it successfully contributes comparable seismic control effect as those having symmetrical cyclic behavior. Additionally, the proposed damper even shows better global performance in controlling acceleration demands. Thus, this paper reduces the concern of using SMA dampers with asymmetric cyclic behavior to a certain degree.