• Molecular & Cellular Toxicology
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• v.3 no.3
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• pp.151-158
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• 2007

The failure of injured axons to regenerate in the mature central nervous system (CNS) has devastating consequences for victims of spinal cord injury (SCI). Traditional strategies to treat spinal cord injured people by using drug therapy and assisting devices that can not help them to recover fully various vital functions of the spinal cord. Many researches have been focused on accomplishing re-growth and reconnection of the severed axons in the injured region. Using cell transplantation to promote neural survival or growth has had modest success in allowing injured neurons to re-grow through the area of the lesion. Strategies for successful regeneration will require tissue engineering approach. In order to persuade sufficient axons to regenerate across the lesion to bring back substantial neurological function, it is necessary to construct an efficient biocompatible bridge (cell-free or implanted with different cell lines as hybrid implant) through the injured area over which axons can grow. Therefore, in this paper, spinal cord and its injury, different strategies to help regeneration of an injured spinal cord are reviewed. In addition, different aspects of designing a biocompatible bridge and its applications and challenges surrounding these issues are also addressed. This knowledge is very important for the development and optimalization of therapies to repair the injured spinal cord.

• Structural Engineering and Mechanics
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• v.82 no.3
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• pp.313-323
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• 2022

Steel laminated elastomeric bearings are commonly used in bridge structures to control displacements and rotations and transfer forces from the superstructure to the substructure. Proper knowledge of design, fabrication and erection procedures is important to ensure stability and adequate structural performance during the lifetime of the bridge. Difference in elevations sometimes leads to large size gaps between the bearing and the girder which makes the grout thickness that is commonly used for leveling deviate beyond standards. This paper investigates the structural response of High Strength Fiber Reinforced Cementitious (HSFRC) thin plinths that are used to close gaps between bearing pads and precast girders. An experimental program was developed for this purpose where HSFRC plinths of different size were cast and tested under vertical loads that simulate bridge loading in service. The structural performance of the plinths was closely monitored during testing, mainly crack propagation, vertical reaction and displacement. Analytically, the HSFRC plinth was analyzed using the beam on elastic foundation theory as the supporting elastomeric bearing pads are highly compressible. Closed form solutions were derived for induced displacement and forces and comparisons were made between analytical and experimental results. Finally, recommendations were made to facilitate the practical use of HSFRC plinths in bridge construction based on its enhanced load carrying capacity in shear and flexure.

• Journal of Information Technology Applications and Management
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• v.23 no.3
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• pp.13-23
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• 2016

In recent years, big data has usefully been deployed by organizations with the aim of getting a better prediction for the future. Moreover, knowledge management systems are being used by organizations to identify and create knowledge. Here, the output from analysis of big data and a knowledge management system are used to develop a new model with the goal of minimizing the cost of implementing new recognized processes including staff training, transferring and employment costs. Strategies are proposed from big data analysis and new processes are defined accordingly. The company requires various skills to execute the proposed processes. Organization's current experts and their skills are known through a pre-established knowledge management system. After a gap analysis, managers can make decisions about the expert arrangement, training programs and employment to bridge the gap and accomplish their goals. Finally, deduction graph is used to analyze the model.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.114-126
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• 2021

This paper compared bridge maintenance in United Stated, United Kingdom, Japan, and Korea. Bridges play an essential role in transportation network and in the economic production process. To provide a desirable level of service to the public within limited budgets, it is required to provide effective bridge maintenance activities (e.g. inspection and repair/rehabilitation) at acceptable level of bridge service. A number of bridges are expected to age rapidly in Korea, which will be the excess burden of government. Since several countries have experienced a number of deteriorated bridges because of aging, the countries aforementioned in this study have already developed comprehensive bridge maintenance programs such as inspection practice and repair/rehabilitation techniques. Therefore, the goal of this paper is to synthesize and to compare useful knowledge on bridge maintenance and bridge crack repair/restoration of deteriorated concrete bridge in the four countries. Finally, recommendations that will serve as guidance to transportation agencies for potential enhancements to bridge maintenance and bridge repairs are presented.

• Asia pacific journal of information systems
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• v.28 no.3
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• pp.220-239
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• 2018

The purpose of the paper is empirically to explore 'design manner', focusing on the designer's knowledge boundary on the designer-user interactions in the design process. This study conducts a field study and observed designer's interactions with actual users in a leading user-centered design firm over three months. The observations revealed how designers bring ideas about users into design without physically interacting with users during the design process. Based on Bourdieu's theory of practice and the concept of boundary objects, this study introduces the concept of 'design manner', by which designers incorporate user's ideas into the design process without actual involvement of users in the process. This paper contributes to the body of knowledge by introducing the design manner in-between designer's and user's knowledge boundaries and argue bridge between theoretical and actual designer-user interactions in the IS design process.

• Advances in concrete construction
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• v.10 no.1
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• pp.49-59
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• 2020

Precast concrete elements in accelerated bridge construction (ABC) extends from superstructure to substructure, precast pile foundation has proven a benefit for regions with fragile ecological environment and adverse geological condition. There is still a lack of knowledge of the seismic behavior and performance of the precast pile foundation. In this study, a 1/8 scaled model of precast pile foundation with elevated cap is fabricated for quasi-static test. The failure mechanism and responses of the precast pile-soil interaction system are analyzed. It is shown that damage occurs primarily in precast pile-soil interaction system and the bridge pier keeps elastic state because of its relatively large cross-section designed for railways. The vulnerable part of the precast pile with elevated cap is located at the embedded section, but no plastic hinge forms along the pile depth under cyclic loading. Hysteretic curves show no significant strength degradation but obvious stiffness degradation throughout the loading process. The energy dissipation capacity of the precast pile-soil interaction system is discussed by using index of the equivalent viscous damping ratio. It can be found that the energy dissipation capacity decreases with the increase of loading displacement due to the unyielding pile reinforcements and potential pile uplift. It is expected to promote the use of precast pile foundation in accelerated bridge construction (ABC) of railways designed in seismic regions.

• Structural Engineering and Mechanics
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• v.86 no.6
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• pp.715-730
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• 2023

Broad studies have addressed the issue of structural element damage identification, however, rubber bearing, as a key component of load transmission between the superstructure and substructure, is essential to the operational safety of a bridge, which should be paid more attention to its health condition. However, regarding the limitations of the traditional bearing damage detection methods as well as few studies have been conducted on this topic, in this paper, inspired by the model updating-based structural damage identification, a two-stage bearing damage identification method has been proposed. In the first stage, we deduce a novel bearing damage localization indicator, called element relative MSE, to accurately determine the bearing damage location. In the second one, the prior knowledge of bearing damage localization is combined with sailfish optimization (SFO) to perform the bearing damage estimation. In order to validate the feasibility, a numerical example of a 5-span continuous beam is introduced, also the noise robustness has been investigated. Meanwhile, the effectiveness and engineering applicability are further verified based on an experimental simply supported beam and actual engineering of the I-40 Bridge. The obtained results are good, which indicate that the proposed method is not only suitable for simple structures but also can accurately locate the bearing damage site and identify its severity for complex structure. To summarize, the proposed method provides a good guideline for the issue of bridge bearing detection, which could be used to reduce the difficulty of the traditional bearing failure detection approach, further saving labor costs and economic expenses.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.563-568
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• 2012

In 2010 the Manila Amendments established the highest practicable standards for officers and engineers. This amendments includes knowledge, understanding, skills, and proficiency required for a deck officer in terms of the BRM (Bridge Resource Management) to reduce human errors, stated in the International Convention on Standards of Training, Cerification and Watchkeeping for Seafarers (STCW). This paper proposes a proper direction to improve BRM education program in Korea. In relation to the BRM program, its contents and education method were analyzed through the satisfactions survey for cadets and the experienced officers. As a consequence, this research gives several suggestions to improve the current BRM course.

• Earthquakes and Structures
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• v.10 no.4
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• pp.789-810
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• 2016

Reinforced concrete (RC) bridges with both skew and curvature are pretty common in areas with complex terrains. Existing studies have shown skewed and/or curved bridges exhibit more complicated seismic performance than straight bridges, and yet related seismic risk studies are still rare. These bridges deserve more studies in low-to-moderate seismic regions than those in seismic-prone areas. This is because for bridges with irregular and complex geometric designs, comprehensive seismic analysis is not always required and little knowledge about actual seismic risks for these bridges in low-to-moderate regions is available. To provide more insightful understanding of the seismic risks and the impact from the geometric configurations, analytical fragility studies are carried out on four typical bridge designs with different geometric configurations (i.e., straight, curved, skewed, skewed and curved) in the mountain west region of the United States. The results show the curved and skewed geometries can considerably affect the bridge seismic fragility in a complex manner, underscoring the importance of conducting detailed seismic risk assessment of skewed and curved bridges in low-to-moderate seismic regions.

• Steel and Composite Structures
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• v.27 no.5
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• pp.647-659
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• 2018

Through extensive research, there exist a new type of connection between railway bridge girders and steel-concrete composite panels. In addition to conventional shear connectors, newly developed blind bolts have been recently adopted for retrofitting. However, the body of knowledge on their influence and application to railway structures has not been thoroughly investigated. This study has thus placed a particular emphasis on the application of blind bolts on the Sydney Harbour Bridge as a feasible alternative constituent of railway track upgrading. Finite element modeling has been used to simulate the behaviours of the precast steel-concrete panels with common types of bolt connection using commercially available package, ABAQUS. The steel-concrete composite track slabs have been designed in accordance with Australian Standards AS5100. These precast steel-concrete panels are then numerically retrofitted by three types of most practical bold connections: head studded shear connector, Ajax blind bolt and Lindapter hollow bolt. The influences of bolt connections on load and stress transfers and structural behaviour of the composite track slabs are highlighted in this paper. The numerical results exhibit that all three bolts can distribute stresses effectively and can be installed on the bridge girder. However, it is also found that Lindapter hollow bolts are superior in minimising structural responses of the composite track slabs to train loading.