• Title/Summary/Keyword: Space Exploitation

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Mechanism Method for Smart Work and the Creation of IT Job (스마트워크와 IT의 일자리창출을 위한 메커니즘 방안)

  • Kim, Man-Ki
    • Journal of Digital Convergence
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    • v.10 no.2
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    • pp.55-61
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    • 2012
  • This space is for the abstract of your study in English. Recently, we began to face a significant change in our daily lives due to the expansion of the use of smartphones. In this regard, this study aims at examining the mechanism of Smart Work, necessary for the creation of job, led by the use of smart devices, and ways of its development. Accordingly, this study defined concepts of Smart Work clearly and analyzed the convergence of information through IT, the exploitation of new markets, derived from information industry, along with foreign cases of job creation through ICT. Furthermore, change in people's cultural recognition is required for the place of smart Work. For example, cluster development based on the public-private cooperation will promote the creation of job. In addition, the cooperation of the academic world and the service industry will play a leading role in developing local economy. To attain this end, the policy support of government for Smart Work and the public-private cooperation are needed.

High-velocity ballistics of twisted bilayer graphene under stochastic disorder

  • Gupta, K.K.;Mukhopadhyay, T.;Roy, L.;Dey, S.
    • Advances in nano research
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    • v.12 no.5
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    • pp.529-547
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    • 2022
  • Graphene is one of the strongest, stiffest, and lightest nanoscale materials known to date, making it a potentially viable and attractive candidate for developing lightweight structural composites to prevent high-velocity ballistic impact, as commonly encountered in defense and space sectors. In-plane twist in bilayer graphene has recently revealed unprecedented electronic properties like superconductivity, which has now started attracting the attention for other multi-physical properties of such twisted structures. For example, the latest studies show that twisting can enhance the strength and stiffness of graphene by many folds, which in turn creates a strong rationale for their prospective exploitation in high-velocity impact. The present article investigates the ballistic performance of twisted bilayer graphene (tBLG) nanostructures. We have employed molecular dynamics (MD) simulations, augmented further by coupling gaussian process-based machine learning, for the nanoscale characterization of various tBLG structures with varying relative rotation angle (RRA). Spherical diamond impactors (with a diameter of 25Å) are enforced with high initial velocity (Vi) in the range of 1 km/s to 6.5 km/s to observe the ballistic performance of tBLG nanostructures. The specific penetration energy (Ep*) of the impacted nanostructures and residual velocity (Vr) of the impactor are considered as the quantities of interest, wherein the effect of stochastic system parameters is computationally captured based on an efficient Gaussian process regression (GPR) based Monte Carlo simulation approach. A data-driven sensitivity analysis is carried out to quantify the relative importance of different critical system parameters. As an integral part of this study, we have deterministically investigated the resonant behaviour of graphene nanostructures, wherein the high-velocity impact is used as the initial actuation mechanism. The comprehensive dynamic investigation of bilayer graphene under the ballistic impact, as presented in this paper including the effect of twisting and random disorder for their prospective exploitation, would lead to the development of improved impact-resistant lightweight materials.

Discussion on Sustaining "Olle" without Losing Integrity of Local Identity - Focused on downtown area called Mu-geun-sung at Jeju city - (올래의 지속가능한 재생방식에 관한 연구 - 제주시 무근성 지역을 중심으로 -)

  • Yi, Yong Kyu;Yi, Yun Kyu;Jing, Li-Yuan
    • Journal of the Korean Institute of Rural Architecture
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    • v.20 no.3
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    • pp.19-26
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    • 2018
  • There are still a number of "olles" existing with traditional alley characteristics in the inner city of Jeju. As a matter of fact, the renovation of old buildings and the protection of alley space are facing a dilemma due to the existence of less than 4m-width-roads in the area of "Mu-geun-sung". This study examines the current status of alley space in "Mu-geun-sung" area; and puts forward to the potential possibility and limitation of alley space regeneration via exploring the applicable scheme of building agreement. In the field survey, a number of regions in inner city of Jeju witnesses the existing majority of invaluable, conventional olles. So as to grasp the feasibility in "Mu-geun-sung" area, we designs a simulating experiment to carry out the Building Agreement; and compares with the current development model in this area. Building Agreement implies to establish gradually a separation of land ownership under the existing unified development of landowners and users, thus to explore a variety of land exploitation systems by separating land ownership and right to use land. As a result, the deterioration of the street landscape results from the increase of building storey numbers. The damages to the surrounding environment brought by the newly built buildings will be minimized as well as keeping the maximum building volume rate. Obviously, these measures will alleviate infringement to the traditional residential sunlight and privacy space effectively, and reduce the pressure from high-rise buildings to the alley space, so that the landscape of the alley will enhance to form a more comfortable alley environment.

Adaptive symbiotic organisms search (SOS) algorithm for structural design optimization

  • Tejani, Ghanshyam G.;Savsani, Vimal J.;Patel, Vivek K.
    • Journal of Computational Design and Engineering
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    • v.3 no.3
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    • pp.226-249
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    • 2016
  • The symbiotic organisms search (SOS) algorithm is an effective metaheuristic developed in 2014, which mimics the symbiotic relationship among the living beings, such as mutualism, commensalism, and parasitism, to survive in the ecosystem. In this study, three modified versions of the SOS algorithm are proposed by introducing adaptive benefit factors in the basic SOS algorithm to improve its efficiency. The basic SOS algorithm only considers benefit factors, whereas the proposed variants of the SOS algorithm, consider effective combinations of adaptive benefit factors and benefit factors to study their competence to lay down a good balance between exploration and exploitation of the search space. The proposed algorithms are tested to suit its applications to the engineering structures subjected to dynamic excitation, which may lead to undesirable vibrations. Structure optimization problems become more challenging if the shape and size variables are taken into account along with the frequency. To check the feasibility and effectiveness of the proposed algorithms, six different planar and space trusses are subjected to experimental analysis. The results obtained using the proposed methods are compared with those obtained using other optimization methods well established in the literature. The results reveal that the adaptive SOS algorithm is more reliable and efficient than the basic SOS algorithm and other state-of-the-art algorithms.

Airship Research and Development in the Areas of Design, Structures, Dynamics and Energy Systems

  • Stockbridge, Casey;Ceruti, Alessandro;Marzocca, Pier
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.2
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    • pp.170-187
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    • 2012
  • Recent years have seen an outpour of revived interest in the use of airships for a number of applications.Present day developments in materials, propulsion, solar panels, and energy storage systems and the need for a more eco-oriented approach to flight are increasing the curiosity in airships, as the series of new projects deployed in recent years show; moreover, the exploitation of the always mounting simulation capabilities in CAD/CAE, CFD and FEA provided by modern computers allow an accurate design useful to optimize and reduce the development time of these vehicles.The purpose of this contribution is to examine the different aspects of airship development with a review of current modeling techniques for airship dynamics and aerodynamics along withconceptual design and optimization techniques, structural design and manufacturingtechnologies and, energy system technologies. A brief history of airships is presented followed by an analysis of conventional and unconventional airships including current projects and conceptual designs.

Monitoring Mangrove Plantation along the Coastal Belts of Bangladesh (1989-2010)

  • Rahman, M. Mahmudur;Pramanik, Md. Abu Taleb
    • Journal of Forest and Environmental Science
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    • v.31 no.3
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    • pp.225-234
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    • 2015
  • Mangroves are important coastal ecosystems and are located at the inter-tidal zones of tropical and sub-tropical belts. The global mangrove forests are declining dramatically because of the conversion of forests to shrimp farming, over-exploitation, pollution and freshwater diversion. The Bangladesh Forest Department initiated mangrove afforestation throughout the coastal belts of Bangladesh in 1966 to provide better protection for the coastal communities. Up to 1990, 120,000 ha of mangroves had been planted and it is one of the largest coastal afforestaton programs in the world. The objective of this study is to exploit the spatial extent of mangrove plantation and their dynamics of changes over the last two decades using multispectral Landsat imagery. The study area covers the coastal areas of Bangladesh that is extended over the eastern part of Sundarbans up to Teknaf, the southern tip of mainland Bangladesh. Mangrove plantations were interpreted visually on computer screen and interactive delineation of forest boundary was done. The mangrove plantation area has been estimated as 32,725, 47,636 and 43,166 ha for the year of 1989, 2000 and 2010, respectively. Mangrove deforestation by human activity has increased almost six times in the recent decade in comparison to the previous one. The mangrove forest loss due to coastal erosion has slightly declined in the 2000s. Mangroves have been lost primarily because of agricultural expansion. The result of this investigation will be helpful to understand the dynamics of mangrove plantation and the main drivers of changes in this coastal ecosystem.

Recent Development of Search Algorithm on Small Molecule Docking (소분자 도킹에서의 탐색알고리듬의 현황)

  • Chung, Hwan Won;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.2 no.2
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    • pp.55-58
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    • 2009
  • A ligand-receptor docking program is an indispensible tool in modern pharmaceutical design. An accurate prediction of small molecular docking pose to a receptor is essential in drug design as well as molecular recognition. An effective docking program requires the ability to locate a correct binding pose in a surprisingly complex conformational space. However, there is an inherent difficulty to predict correct binding pose. The odds are more demanding than finding a needle in a haystack. This mainly comes from the flexibility of both ligand and receptor. Because the searching space to consider is so vast, receptor rigidity has been often applied in docking programs. Even nowadays the receptor may not be considered to be fully flexible although there have been some progress in search algorithm. Improving the efficiency of searching algorithm is still in great demand to explore other applications areas with inherently flexible ligand and/or receptor. In addition to classical search algorithms such as molecular dynamics, Monte Carlo, genetic algorithm and simulated annealing, rather recent algorithms such as tabu search, stochastic tunneling, particle swarm optimizations were also found to be effective. A good search algorithm would require a good balance between exploration and exploitation. It would be a good strategy to combine algorithms already developed. This composite algorithms can be more effective than an individual search algorithms.

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Modelling of Image Acquisition Scenario and Verification of Mission Planning Algorithm for SAR Satellite (SAR위성의 영상획득 시나리오 모델링 및 임무설계 알고리즘 성능검증)

  • Shin, Hohyun;Kim, Jongpil
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.47 no.8
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    • pp.590-598
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    • 2019
  • Today, satellites are widely used in many fields like communication and image recoding. The image acquired by satellites contains variety information of wide region. Therefore, they are used for agriculture, resource exploitation and management, and military purpose. The satellite is required to acquire images effectively in a given time period. Because the period that satellites can acquire images is very restrictive. In this study, the modeling of processing time and attitude maneuvering for satellite image acquisition is performed. From this modeling, mission planning algorithm using heuristic evaluation function is suggested and performance of the proposed algorithm is verified by numerical simulation.

Optimal Allocation of Distributed Solar Photovoltaic Generation in Electrical Distribution System under Uncertainties

  • Verma, Ashu;Tyagi, Arjun;Krishan, Ram
    • Journal of Electrical Engineering and Technology
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    • v.12 no.4
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    • pp.1386-1396
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    • 2017
  • In this paper, a new approach is proposed to select the optimal sitting and sizing of distributed solar photovoltaic generation (SPVG) in a radial electrical distribution systems (EDS) considering load/generation uncertainties. Here, distributed generations (DGs) allocation problem is modeled as optimization problem with network loss based objective function under various equality and inequality constrains in an uncertain environment. A boundary power flow is utilized to address the uncertainties in load/generation forecasts. This approach facilitates the consideration of random uncertainties in forecast having no statistical history. Uncertain solar irradiance is modeled by beta distribution function (BDF). The resulted optimization problem is solved by a new Dynamic Harmony Search Algorithm (DHSA). Dynamic band width (DBW) based DHSA is proposed to enhance the search space and dynamically adjust the exploitation near the optimal solution. Proposed approach is demonstrated for two standard IEEE radial distribution systems under different scenarios.

Observer-Teacher-Learner-Based Optimization: An enhanced meta-heuristic for structural sizing design

  • Shahrouzi, Mohsen;Aghabaglou, Mahdi;Rafiee, Fataneh
    • Structural Engineering and Mechanics
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    • v.62 no.5
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    • pp.537-550
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    • 2017
  • Structural sizing is a rewarding task due to its non-convex constrained nature in the design space. In order to provide both global exploration and proper search refinement, a hybrid method is developed here based on outstanding features of Evolutionary Computing and Teaching-Learning-Based Optimization. The new method introduces an observer phase for memory exploitation in addition to vector-sum movements in the original teacher and learner phases. Proper integer coding is suited and applied for structural size optimization together with a fly-to-boundary technique and an elitism strategy. Performance of the proposed method is further evaluated treating a number of truss examples compared with teaching-learning-based optimization. The results show enhanced capability of the method in efficient and stable convergence toward the optimum and effective capturing of high quality solutions in discrete structural sizing problems.