• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.471-478
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• 2012

A carbon capture and storage (CCS) plays a very important role to reduce $CO_2$ dramatically in $CO_2$ emission sources which are distributed throughout various areas. Numerous research works have been undertaken to analyze the techno-economic feasibility of planning the CCS infrastructure. However, uncertainties such as $CO_2$ emissions, $CO_2$ reduction costs, and carbon taxes may exist in various impact factors of the CCS infrastructure. However, few research works have adopted these uncertainties in designing the CCS infrastructure. In this study, a two-stage stochastic programming model is developed for planning the CCS infrastructure under uncertain operating costs and carbon taxes. It can help determine where and how much $CO_2$ to capture, store or transport for the purpose of minimizing the total annual $CO_2$ reduction cost in handling the uncertainties while meeting the $CO_2$ mitigation target. The capability of the proposed model to provide correct decisions despite changing the operating costs and carbon taxes is tested by applying it to a real case study based on Korea. The results will help to determine planning of a CCS infrastructure under uncertain environments.

• Earthquakes and Structures
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• v.9 no.3
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• pp.603-623
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• 2015

The scale and nature of the recent earthquakes in the world and the related earthquake disaster index coerce the concerned community to become anxious about it. Therefore, it is crucial that seismic lateral load effect will be appropriately considered in structural design. Application of seismic isolation system stands as a consistent alternative against this hazard. The objective of the study is to evaluate the structural and economic feasibility of reinforced concrete (RC) buildings with base isolation located in medium risk seismic region. Linear and nonlinear dynamic analyses as well as linear static analysis under site-specific bi-directional seismic excitation have been carried out for both fixed based (FB) and base isolated (BI) buildings in the present study. The superstructure and base of buildings are modeled in a 3D finite element model by consistent mass approach having six degrees of freedom at each node. The floor slabs are simulated as rigid diaphragms. Lead rubber bearing (LRB) and High damping rubber bearing (HDRB) are used as isolation device. Change of structural behaviors and savings in construction costing are evaluated. The study shows that for low to medium rise buildings, isolators can reduce muscular amount of base shears, base moments and floor accelerations for building at soft to medium stiff soil. Allowable higher horizontal displacement induces structural flexibility. Though incorporating isolator increases the outlay, overall structural cost may be reduced. The application of base isolation system confirms a potential to be used as a viable solution in economic building design.

• Clean Technology
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• v.24 no.4
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• pp.357-364
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• 2018

Studies on the production of biogas from third generation biomass, such as micro- and macroalgae, have been conducted through experiments of various scales. In this paper, we investigated the feasibility of commercialization of integrated combined heat and power (CHP) production using biogas derived from macroalgae, i.e., seaweed biomass. For this purpose, an integrated CHP plant of industrial scale, consisting of solid oxide fuel cells, gas turbine and organic Rankine cycle, was designed and simulated using a commercial process simulator. The cost of each equipment in the plant was estimated through the calculated heat and mass balances from simulation and then the techno-economic analysis was performed. The designed integrated CHP process produces 68.4 MW of power using $36ton\;h^{-1}$ of biogas from $62.5ton\;h^{-1}$ (dry basis) of brown algae. Based on these results, various scenarios were evaluated economically and the levelized electricity cost (LEC) was calculated. When the lifetime of SOFC is 5 years and its stack price is $$225kW^{-1}$, the LEC was 12.26 ¢ $kWh^{-1}$, which is comparable to the conventional fixed power generation.

• Advances in nano research
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• v.6 no.1
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• pp.81-92
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• 2018

Biosynthesis of nanoparticles has acquired particular attention due to its economic feasibility, low toxicity and simplicity of the process. Extracellular synthesis of nanoparticles by bacteria and fungi has been stated to be brought about by enzymes and other reducing agents that may be secreted in the culture medium. The present study was carried out to determine the underlying mechanisms of extracellular silver nanoparticle synthesis by Pseudomonas hibiscicola isolated from the effluent of an electroplating industry in Mumbai. Synthesized nanoparticles were characterized by spectroscopy and electron microscopic techniques. Protein profiling studies were done using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (1D-SDS PAGE) and subjected to identification by Mass Spectrometry. Characterization studies revealed synthesis of 50 nm nanoparticles of well-defined morphology. Total protein content and SDS PAGE analysis revealed a reduction of total protein content in test (nanoparticles solution) samples when compared to controls (broth supernatant). 45.45% of the proteins involved in the process of nanoparticle synthesis were identified to be oxidoreductases and are thought to be involved in either reduction of metal ions or capping of synthesized nanoparticles.

• Journal of Technology Innovation
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• v.13 no.1
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• pp.213-246
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• 2005

Despite of the impressive progress made in the Evolutionary techno-economics during the last two decades, there have been very little, if not at all, theoretical advancement in explaining an endogenous mechanism of transforming a technological paradigm within self-perpetuatingstructural dynamics. The question poorly attempted was raised by Schumpeter a century ago in his effort to overcome the well-known 'Walras' trap'. Although there have been increasing number of researchers recently tackling the issue quite seriously from within the Evolutionary school, I see it that radical reconstruction of the basic principle of Evolutionary research framework is urgently needed to solve the century long fundamental question, from evolutionary approach to transformational approach. In the paper, I will show the theoretical feasibility of explaining an endogenous mechanism of paradigm transformation, relying upon the concept of localized dynamics and the concept of morphogenetic structuration. It should be emphasized that there must be aendogenous process of deepening structural Instability generated in the process of economic coordination to secure efficient circular flow. The concept of development bottleneck initiated by the Baumol's cost disease could be regarded as one of the important source of such mechanism. Unfortunately, however, it is a brief conceptual description presented in the paper rather than a comprehensive analytical model, due to the space limitation imposed.

• Wind and Structures
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• v.21 no.6
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• pp.625-639
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• 2015

Monopiles have been most widely used for supporting offshore wind turbines (OWTs) in shallow water areas. However, multi-member lattice-type structures such as jackets and tripods are also considered good alternatives to monopile foundations for relatively deep water areas with depth ranging from 25-50 m owing to their technical and economic feasibility. Moreover, jacket structures have been popular in the oil and gas industry for a long time. However, several unsolved technical issues still persist in the utilization of multi-member lattice-type supporting structures for OWTs; these problems include pile-soil-interaction (PSI) effects, realization of dynamically stable designs to avoid resonances, and quick and safe installation in remote areas. In this study, the effects of PSI on the dynamic properties of bottom-fixed OWTs, including monopile-, tripod- and jacket-supported OWTs, were investigated intensively. The tower and substructure were modeled using conventional beam elements with added mass, and pile foundations were modeled with beam and nonlinear spring elements. The effects of PSI on the dynamic properties of the structure were evaluated using Monte Carlo simulation considering the load amplitude, scouring depth, and the uncertainties in soil properties.

• Geomechanics and Engineering
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• v.8 no.5
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• pp.631-647
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• 2015

Engineers may encounter unpredictable cavities, sinkholes and karst conduits while tunneling in karst area, and water inrush disaster frequently occurs and endanger the construction safety, resulting in huge casualties and economic loss. Therefore, an optimal classification method based on grey system theory (GST) is established and applied to accurately predict the occurrence probability of water inrush. Considering the weights of evaluation indices, an improved formula is applied to calculate the grey relational grade. Two evaluation indices systems are proposed for risk assessment of water inrush in design stage and construction stage, respectively, and the evaluation indices are quantitatively graded according to four risk grades. To verify the accuracy and feasibility of optimal classification method, comparisons of the evaluation results derived from the aforementioned method and attribute synthetic evaluation system are made. Furthermore, evaluation of engineering practice is carried through with the Xiakou Tunnel as a case study, and the evaluation result is generally in good agreement with the field-observed result. This risk assessment methodology provides a powerful tool with which engineers can systematically evaluate the risk of water inrush in karst tunnels.

• Steel and Composite Structures
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• v.17 no.3
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• pp.237-252
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• 2014

The use of composite structures is increasingly present in civil building works. Composite Box Girder Bridges (CBGB), particularly, are study of effect of shear connector's numbers and distribution on the behavior of CBGBs is submitted. A Predicti structures consisting of two materials, both connected by metal devices known as shear connectors. The main functions of these connectors are to allow for the joint behavior of the girder-deck, to restrict longitudinal slipping and uplifting at the element's interface and to take shear forces. This paper presents 3D numerical models of CBGBs to simulate their actual structural behavior, with emphasis on the girder-deck interface. Additionally, a Prediction of several FE models is assessed against the results acquired from a field test. A number of factors are considered, and confirmed through experiments, especially full shear connections, which are obviously essential in composite box girder. A good representation for shear connectors by suitable element type is considered. Numerical predictions of vertical displacements at critical sections fit fairly well with those evaluated experimentally. The agreement between the FE models and the experimental models show that the FE model can aid engineers in design practices of box girder bridges. Preliminary results indicate that number of shear studs can be significantly reduced to facilitate adoption of a new arrangement in modeling CBGBs with full composition. However, a further feasibility study to investigate the practical and economic aspects of such a remedy is recommended, and it may represent partial composition in such modeling.

• Journal of the Korean Society of Costume
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• v.66 no.2
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• pp.61-75
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• 2016

The purpose of this study was to develop interactive smart clothing based on visual and tactile sensitivities to promote non-verbal communication between people with hearing impairments. The study analyzed various cases of interactive smart clothing, different non-verbal communication tools, as well as results of user demand survey to extract essential factors. Then these factors were categorized into technology or design concept. The technological aspect of the development considered the following factors: the usability, detachability, purposiveness, and economic feasibility. The design aspect considered the following factors: the usability, detachability, formativeness and wearability. A prototype was designed considering the user's requirements. The developed prototype had sensors, Bluetooth technology, and gave access to wireless communication in order to enable non-verbal communication between people with hearing impairments.

• Structural Engineering and Mechanics
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• v.65 no.2
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• pp.183-190
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• 2018

The prestressed concrete (PSC) technology that was first developed by Freyssinet has significantly improved over the past century in terms of materials and structural design in order to build longer, slender, and more economic structures. The application of prestressing method in structures, which is determined by the pre-tension or post-tension processes, is also affected by the surrounding conditions such as the construction site, workforce skills, and local transportation regulations. This study proposes a prestressed concrete girder design based on a hybrid segment concept. The adopted approach combines both pre-tension and post-tension methods along a simple span bridge girder. The girder was designed using newly developed 2400 MPa PS strands and 60 MPa high-strength concrete. The new concept and high strength materials allowed longer span, lower girder depth, less materials, and slender design without affecting the lateral stability of the girder. In order to validate the applicability of the proposed hybrid prestressed segments girder, a full-scale 35 m girder was fabricated, and experimental tests were performed under various fatigue and static loading conditions. The experimental results confirmed the feasibility of the proposed long-span girder as its performance meets the railway girder standards. In addition, the comparison between the measured load-displacement curve and the simulation results indicate that simulation analysis can predict the behavior of hybrid segments girders.