• Journal of Science and Technology Studies
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• v.9 no.2
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• pp.51-78
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• 2009

Usually, Technological failures have been recognized as a mundane and inevitable process of trial and error for finally achieving success, or pathological technologies clearly different from success. These approaches easily ignore that a failed technology also constructed complex technological networks with various actors for some times. Consequently, failed technologies failed not only technological realization, but also got a proper evaluation. This paper explore the emergence and decline of the city phone project (CT-2 technology), the very typical failure cases in the telecommunications industry at Korea. This story shows that the city phone project with low-price and low-technology could constructed a stable network at agreement the result from interaction between various actors, and then, changed because various actors gave technologies different meaning and desire. Finally, it suggests that collapse of its technological network was attributed to uncertain future and contingent, rather than technological limits.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.481-501
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• 2007

Excessive rainfalls due to climatic changes can trigger an increase in rainfall-induced slope failures that pose real threats to both lives and properties. Many high slopes in residual soils could stand at a steep angle, but failed during or after rainfall. Commonly, these slopes have a deep groundwater table and negative pore-water pressures in the unsaturated zone above the groundwater table contribute to the shear strength of soil and consequently to factor of safety of the slope. Stability assessment of slope under rainfall requires information on rate of rainwater infiltration in the unsaturated zone and the resulting changes in pore-water pressure and shear strength of soil. This paper describes the application of unsaturated soil mechanics principles and theories in the assessment of rainfall effect on stability of slope through proper characterization of soil properties, measurement of negative pore-water pressures, seepage and slope stability analyses involving unsaturated and saturated soils. Factors controlling the rate of changes in factor of safety during rainfall and a preventive method to minimize infiltration are highlighted in this paper.

• Nuclear Engineering and Technology
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• v.37 no.2
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• pp.159-166
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• 2005

Human reliability assessment (HRA) is conducted on the unspoken premise that 'human error' is a meaningful concept and that it can be associated with individual actions. The basis for this assumption it found in the origin of HRA, as a necessary extension of PSA to account for the impact of failures emanating from human actions. Although it was natural to model HRA on PSA, a large number of studies have shown that the premises are wrong, specifically that human and technological functions cannot be decomposed in the same manner. The general experience from accident studies also indicates that action failures are a function of the context, and that it is the variability of the context rather than the 'human error probability' that is the much sought for signal. Accepting this will have significant consequences for the way in which HRA, and ultimately also PSA, should be pursued.

• Journal of Digital Convergence
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• v.8 no.2
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• pp.29-42
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• 2010

To improve the performance of R&D investments, government has taken great efforts for advancing the structure and process in R&D systems. However, due to the drastic internal/external changes in the technological environment and the steady increase of investment scale, the necessity for a innovative approach which accomplishes returns to scale through the utilization of various external resources is emerging. In this regard, open innovation approach can minimize the possibility of government failures by strengthening the absorptive capacity of external resources and enhancing the cooperation and participation of diverse innovative participants within the R&D system. This paper evaluates the previous researches and government policies concerning the performances of government R&D investments, and presents the connectivity between open innovation and its possible contribution to the improvement of R&D investment performances.

• Structural Engineering and Mechanics
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• v.53 no.4
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• pp.767-780
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• 2015

Delaminations and cracks are common failures in structures. They may significantly reduce the stiffness of the structure and affect their vibration characteristics. In the present study, an analytical solution is developed to study the effect of an edge crack on the vibration characteristics of delaminated beams. The rotational spring model, the 'free mode' and 'constrained mode' assumptions in delamination vibration are adopted. This is the first study on how an edge crack affects the vibration characteristic of delaminated beams and new nondimensional parameters are developed accordingly. The crack may occur inside or outside the delaminated area and both cases are studied. Results show that the effect of delamination length and thickness-wise location on reducing the natural frequencies is aggravated by an increasing crack depth. The location of the crack also influences the effect of delamination, but such influence is different between crack occurring inside and outside the delaminated area. The difference of natural frequencies between 'free mode' and 'constrained mode' increases then decreases as the crack moves from one side of the delaminated region to the other side, peaking at the middle. The analytical results of this study can serve as the benchmark for FEM and other numerical solutions.

• Wind and Structures
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• v.29 no.1
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• pp.15-32
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• 2019

Much advancement has been made in wind power due to modern technological developments. The wind energy technology is the world's fastest-growing energy option. More power can be generated from wind energy by the use of new design and techniques of wind energy machines. The geographical areas with suitable wind speed are more favorable and preferred for wind power deployment over other sources of energy generation. Today's wind turbines are mainly the horizontal axis wind turbines (HAWTs) and vertical axis wind turbines (VAWTs). HAWTs are commercially available in various sizes starting from a few kilowatts to multi-megawatts and are suitable for almost all applications, including both onshore and offshore deployment. On the other hand, VAWTs finds their places in small and residential wind applications. The objective of the present work is to review the technological development, available sizes, efficiencies, structural types, and structural stability of VAWTs. Structural stability and efficiencies of the VAWTS are found to be dependent on the structural shape and size.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4191-4203
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• 2023

Robotics applications are greatly needed in hazardous locations, e.g., fusion and fission reactors, where robots must perform delicate and complex tasks under ionizing radiation conditions. The drawback is that some robotic parts, such as active electronics, are susceptible to radiation. It can lead to unexpected failures and early termination of the robotic operation. This paper analyses the ionizing radiation effect from 0.09 to 1.5 Gy/s in robotic components (microcontrollers, servo motors and temperature sensors). The first experiment compares the performance of various microcontroller types and their actuators and sensors, where different mitigation strategies are applied, such as using Radiation-Hardened (Rad-Hard) microcontrollers or shielding. The second and third experiments analyze the performance of a 3-Degrees of Freedom (DoF) robotic arm, evaluating its components' responses and trajectory. This study enhances our understanding and expands our knowledge regarding radiation's impact on robotic arms and components, which is useful for defining the best strategies for extending the robots' operational lifespan, especially when performing maintenance or inspection tasks in radiation environments.

• Journal of Technology Innovation
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• v.12 no.2
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• pp.67-97
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• 2004

Practical experience with technology implementation of the upgrading of very small village industries in India suggests that innovation failures are not merely a result of the lack of proper interaction between the users and suppliers of technologies under implementation, but also a result of adoption of the primitive conception of competitiveness in their practice of technology development. The approach of promoting the small producers to become individually competitive by using labour intensive, small-scale intermediate technologies is proving to be totally inadequate for the achievement of technological efficiency in a dynamic sense. Guided by a primitive notion of competitiveness, the suppliers of intermediated technologies are thus being led into limiting their technological efforts in the sectors of direct interest to the rural industrial clusters to the transitional objectives of mainly poverty alleviation. Consequently they have not been able to target the small producers of these village industries for the objectives of business growth. This paper posits that under competitive conditions the self-employed small producer has not only to come together for access to resources, but also has to emerge as a multi-sectoral collective of producers, co-operating in production. With the aim to draw lessons that are generic and have policy implications for the development of innovation systems for local economy based rural industrial clusters and value chains, the author analyses in this paper the experience of innovation in technological systems for the sectors of leather, fruits and vegetable processing and agro processing by the People's Science Movement with the help of the Ministry of Science and Technology and other sectoral ministries in India where rural poor were required to pool the resources and capabilities for raising the scale and scope of their collective production organization.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.2
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• pp.73-78
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• 2005

The management of technological systems will become increasingly complex. Safe and reliable software operation is a significant requirement for many types of system. So, with software fault tolerance, we want to prevent failures by tolerating faults whose occurrences are known when errors are detected. This paper presents a fault location algorithm for single-phase-to-ground faults on the teed circuit of a parallel transmission line using software fault tolerance technique. To find the fault location of transmission line, we have to solve the 3rd order transmission line equation. A significant improvement in the identification of the fault location was accomplished using the N-Version Programming (NVP) design paradigm. The delivered new algorithm has been tested with the simulation data obtained from the versatile EMTP simulator.

• Journal of Information Technology Applications and Management
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• v.14 no.3
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• pp.79-94
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• 2007

Cases of botched information systems implementation have been surfaced due to poor IS project management and control. One major source of such failures is the perceptual difference between the participants of IS projects who should define potential risk factors well before considered IS projects are launched. Based on risk factors cited from prior works, this paper empirically examines the risk factors associated with IS service project management to analyze perceptual differences between the IS service providers and customers in Korea. Data analyses found significant differences in the area of scheduling/resource, technological newness, communications, and sponsorship/ownership while statistically significant differences were observed in eleven individual factors out of forty six risk factors. Risk factors are also ordered in terms of perceived importance to highlight the critical differences.