• Journal of agriculture & life science
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• v.45 no.3
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• pp.59-68
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• 2011

In Korea, most of the locations of the cemeteries and burial vault are in forest lands. The utilization of forest land for this particular purpose is very inefficent and considered to be a serious problem. National government (Forest Service), local governments (Incheon city), and religious corporation (eunhoe Temple) are creating new burial methods to solve the inefficiency in forest utilization. In this study, awareness of Koreans and Japaneses on tree burial problems were compared. Based from the results of the survey, more than 80% of the respondents are aware of the problems. However, the burial culture in Korea still has many problems. Operation and management of tree burial is not being done by experts and sufficient information regarding to this type of burial still needs to developed. To solve these problems, eco-friendly burial, which is considered as new funeral culture, is now being created. In the case of Ichinoseki City in Iwate prefecture in Japan, improving the residential environment greatly affected the tree burial practices. This town was chosen for this study due to its characteristics of being a tourism area which greatly affecting the economy of this town. Another study site of this study was located in Sangju city. The changing social environement and the perception of the people regarding on the services being provided to the people were examined thru questionnaire survey. Specifically, this study analyzed the practices and beliefs of the people regarding the tree burial culture.

• Geophysics and Geophysical Exploration
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• v.1 no.1
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• pp.49-56
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• 1998

Seismic tomography has been widely used as high resolution subsurface imaging techniques in engineering applications. Although most of the techniques have been using travel time inversion, waveform method is being driven forward owing to the progress of computational environments. Although full-waveform inversion method has been known as the best method in terms of model resolving power without high-frequency restriction and weak scattering approximation, it has practical disadvantage that it is apt to get stuck in local minimum if the initial guess is far from the actual model and it consumes so much time to calculate. In this study, 2-D full-waveform inversion algorithm in acoustic medium is developed, which uses result of traveltime tomography as initial model. From the application on synthetic data, it is proved that this approach can efficiently reduce the problem of conventional approaches: our algorithm shows much faster convergence rate and improvement of model resolution. Result of application on physical modeling data also shows much improvement. It is expected that this algorithm can be applicable to real data.

• Geophysics and Geophysical Exploration
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• v.15 no.3
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• pp.129-135
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• 2012

The simultaneous-source full waveform inversion improves the applicability of full waveform inversion by reducing the computational cost. Since this technique adopts simultaneous multi-source for forward modeling, unwanted events remain in the residual seismograms when the receiver geometry of field acquisition is different from that of numerical modeling. As a result, these events impede the convergence of the full waveform inversion. In particular, the streamer-type data with limited offsets is the most difficult data to apply the simultaneous-source technique. To overcome this problem, the global-correlation-based objective function was suggested and it was successfully applied to the simultaneous-source full waveform inversion in time domain. However, this method distorts residual wavefields due to the modified objective function and has a negative influence on the inversion result. In addition, this method has not been applied to the frequency-domain simultaneous-source full waveform inversion. In this paper, we apply a timedamping function to the observed and modeled data, which are used to compute global correlation, to minimize the distortion of residual wavefields. Since the damped wavefields optimize the performance of the global correlation, it mitigates the distortion of the residual wavefields and improves the inversion result. Our algorithm incorporates the globalcorrelation-based full waveform inversion into the frequency domain by back-propagating the time-domain residual wavefields in the frequency domain. Through the numerical examples using the streamer-type data, we show that our inversion algorithm better describes the velocity structure than the conventional global correlation approach does.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.33-42
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• 2021

Modern aircraft fighters improve the maneuverability and performance with the RSS (Relaxed Static Stability) concept and therefore these aircrafts are susceptible to abrupt pitch-up in the transonic and moderate Angle-of-Attack (AoA) flight region where the shock wave is formed and the mean aerodynamic center is moved forward during deceleration. Also, the modeling of the aircraft flying in this flight region is very difficult due to complex flow filed and unpredictable dynamic characteristics and the model-based control design technique does not fully cover this problem. In this paper, we analyzed the performance of the TPMC (Transonic Pitching Moment Compensation) control based on the model-based IDI (Incremental Dynamic Inversion) and the Hybrid IDI based on the model and sensor based IDI during the SDT (Slow Down Turn) in transonic region. As the result, the Hybrid IDI had quicker response and the same maximum g suppression performance and provided the predictable flying qualities compared to the TPMC control. The Hybrid IDI improved the performance of the Over-G protection controller in the transonic and moderate AoA region

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.146-154
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• 2019

Recently, a system has been developed and applied to establish and utilize HD maps through R&D. The biggest problem, however, is the lack of a proper HD map update system, which requires the development and adoption of such a system as soon as possible. In addition, in the case of updating HD maps for automated driving, integrity and accuracy of maps are required for safe driving, so an test of these technologies and data quality is required. In April 2018, the Ministry of Land, Infrastructure and Transport implemented a project to 'Develop Technology to Demonstrate and Share the Instant Road Change Detection and Update Technology for automated driving. This paper analyzed the technology for updating map based on the investigation and analysis of relevant technology trends for the development of integrated demonstration and sharing technology of road change rapid detection and updating map technology, and put forward the criteria for road change rapid detection, integrated quality verification of update technology. It is expected that the results of this study will contribute to quality assurance of HD maps that support safety driving for automated vehicles.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.3
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• pp.167-174
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• 2021

Recent investigation into the integrity of nuclear containment buildings has highlighted the importance of developing an elaborate diagnostic method to evaluate the distribution and size of cavities inside concrete walls. As part of developing such a method, this paper presents a finite element approach to modeling elastic waves propagating in the containment building walls of a nuclear power plant. We introduce a perfectly matched layer (PML) wave-absorbing boundary to limit the large-scale nuclear containment wall to the region of interest. The formulation results in a semi-discrete form with symmetric damping and stiffness matrices. The transient elastic wave equations for a mixed unsplit-field PML were solved for displacement and stresses in the time domain. Numerical results show that the sensitivity of displacement, velocity, acceleration, and stresses is large depending on the size and location of the cavity. The dynamic response of the wall slightly differs depending on the existence of the containment liner plate. The results of this study can be applied to a full-waveform inversion approach for characterizing cavities inside a containment wall.

• Journal of Korea Entertainment Industry Association
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• v.13 no.4
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• pp.27-37
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• 2019

This study empirically identified and sought implications for the degree of desire by film crews to participate in overseas production and the factors affecting them, based on the recognition that the active participation of skilled film crews in overseas production and joint ventures can be an alternative to the poor treatment of domestic film industry sites and the reduction of job losses due to problems with career barriers. In order for respondents to verify research questions, binomial logistic and marginal effects analysis using SPSS and STATA, the data obtained by surveying 402 film crews operating in various areas. The notable findings are as follow: First, about 65%(263 people) of the respondents expressed their desire to participate in overseas activity, indicating that a considerable number of film crews are looking forward to opportunities with overseas productions. Second, major factors that have a positive effect on film crews' need to participate in overseas activities have been found to be professionality, artistic identity, Korean Wave persistence, and career barriers. In other words, the higher the professionality, the more clearly the identity of the artist, the more positive expectations of the possibility of the Korean Wave continuing, and the more serious the problem of career disability, the clearer was the desire to participate in overseas production and joint-work activities.

• (The) Research of the performance art and culture
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• no.19
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• pp.35-60
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• 2009

I insisted that the structure should be set newly, pointing out problems in a structure of the big gut, Jain dano je in this paper. Although, the big gut is playing now in Jain dano je, the features of gut geo-ri are vague ; that's why gut geo-ri and performances are entangled. Therefore, the gut geori showing strange structures not fitted with korean shamanist custom is playing these days like Pawangbyeolhui and Eoudong geori. The detailed procedure is also awkward. It is mixed with aspects of shaman custom in each region, instead showing features of regions. What's more, it became a dance drama, not gut geo-ri with several shamans dancing in a gut. Overcoming these problems, the big gut will be a cultural asset. Therefore, when considering the structure of korean gut, we will fit the order of gut geo-ri into the system of divine spirits keeping a plot-opening, developing and closing. It should be a gut geori-oriented play with only gut geo-ri things. Gut should be gone forward main shaman-oriented gut, setting up a main shaman who takes charge of each gut geo-ri. We should find out a new shaman who knows gut of Gyeong sang province well, if shaman who now takes charge of it has a problem. The big gut of Jain dano je became a part of intangible cultural assets. The performance is not a subject of curiosity and people's interests any more as it was in a past. It should be a traditional performance of representing our traditional culture. We should reorganize an epochal gut geo-ri after reexamining gut geo-ri which has played so far.

• Journal of Aerospace System Engineering
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• v.16 no.1
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• pp.49-55
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• 2022

The role of drones has been expanded to various fields such as agriculture, construction, and logistics. In particular, agriculture drones are emerging as an effective alternative to solve the problem of labor shortage and reduce the input cost. In this study therefore, we proposed the fruit recognition algorithm and harvesting mechanism for fruit harvesting drone system that can safely harvest fruits at high positions. In the fruit recognition algorithm, we employ "You-Only-Look-Once" which is a deep learning-based object detection algorithm and verify its feasibility by establishing a virtual simulation environment. In addition, we propose the fruit harvesting mechanism which can be operated by a single driving motor. The rotational motion of the motor is converted into a linear motion by the scotch yoke, and the opened gripper moves forward, grips a fruit and rotates it for harvesting. The feasibility of the proposed mechanism is verified by performing Multi-body dynamics analysis.

• 한국노년학
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• v.29 no.2
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• pp.563-578
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• 2009

Public pension system of western welfare states has been maintained by transfers of public resources between working-age population and old-age population. But population aging cause the problem of fiscal burden on pension financing, so cutback on public spending for the elderly has been on the issue at public agenda. The argument on public spending for the elderly is more aggressively proceeded in the United States than any other welfare states. The argument is concerned with the problems of generation and is going under the rhetoric name of 'Generational Equity' which contends unequal distribution of social resources such as federal budget within generations. This article analyzes the background of 'Generational Equity' perspective and the reason why that argument is actively going forward in the U. S. and political-economy context of that argument. Generational Equity perspective contends that the elderly are getting more benefits and high spending on the elderly has contributing to the rising poverty rate of children. But there are lots of objection to this perspective on the ground that the perspective has weak positive evidences. The reason that 'Generational Equity' perspective has the power only in the U. S. but other welfare states is mainly due to that pluralistic political regime and selective welfare system. This research presents that political-economy meaning of 'Generational Equity' perspective is related to the political regime and welfare system of the society itself. And this research has the implication that our society having a selective welfare system would take a risk of encountering 'Generational Equity' social debate in the near future.