• Journal of Advanced Technology Convergence
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• v.2 no.3
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• pp.17-24
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• 2023

I am designing a research paper with the aim of studying hybrid vehicles. Hybrid vehicles, as the next-generation automobiles, feature a combination of internal combustion engines and battery engines, resulting in a revolutionary reduction in fuel consumption and harmful gas emissions compared to conventional vehicles. The electric motor in hybrid cars derives power from a high-voltage battery installed within the vehicle, which is recharged during vehicle motion. In contrast to traditional cars, which often experience energy losses due to idling caused by traffic congestion, hybrid systems optimize efficiency by skillfully managing the interplay between the internal combustion engine and the electric motor. This approach effectively addresses the inherent drawbacks of gasoline or diesel engines.Hybrid cars offer an array of benefits, including improved fuel efficiency, environmental friendliness, cost-effectiveness, and reduced noise emission. Consequently, they are progressively becoming a favored alternative among a growing number of individuals. This research endeavor has the potential to contribute towards curbing environmental pollution and dedicating efforts to future automotive research.

• Journal of Advanced Navigation Technology
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• v.27 no.2
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• pp.182-189
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• 2023

Depth estimation is a key technology in 3D map generation for autonomous driving of vehicles, robots, and drones. The existing sensor-based method has high accuracy but is expensive and has low resolution, while the camera-based method is more affordable with higher resolution. In this study, we propose self-attention-based unsupervised monocular depth estimation for UAV camera system. Self-Attention operation is applied to the network to improve the global feature extraction performance. In addition, we reduce the weight size of the self-attention operation for a low computational amount. The estimated depth and camera pose are transformed into point cloud. The point cloud is mapped into 3D map using the occupancy grid of Octree structure. The proposed network is evaluated using synthesized images and depth sequences from the Mid-Air dataset. Our network demonstrates a 7.69% reduction in error compared to prior studies.

• Composites Research
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• v.19 no.5
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• pp.12-19
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• 2006

In this paper, conceptual structural design of the main wing for a small scale WIG(Wing in Ground Effect) among high speed ship projects, which will be a high speed maritime transportation system for the next generation in Rep. of Korea, was performed. The Carbon/Epoxy material was selected for the major structure, and the skin-spar with a foam sandwich structural type was adopted for improvement of lightness and structural stability. As a design procedure for the present study, firstly the design load was estimated through the critical flight load case study, and then flanges of the front and rear spars from major bending loads and the skin and the spar webs from shear loads were preliminarily sized using the netting rule and the rule of mixture. Stress analysis was performed by a commercial FEA code, NASTRAN. From the stress analysis results for the first designed wing structure, it was confirmed that the upper skin between the front spar and the rear spar was unstable fer the buckling. Therefore in order to solve this problem, a middle spar and the foam sandwich type structure at the skin and the web were added. After design modification, the structural safety and stability for the final design feature was confirmed. In addition to this, the insert bolt type structure with eight high strength bolts to fix the wing structure to the fuselage was adopted for easy assembly and removal as well as in consideration of more than 20 years fatigue life.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.360-360
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• 2022

토양수분과 유출 간 관계를 정량화하는 것은 수문 기작 및 유출 발생 과정의 이해를 위한 중요한 정보를 제공한다. 특히, 유출과정의 특성화는 수문 사상에 따른 불포화대 내 토양수 및 토사 손실 제어와 산사태 및 비점오염원 발생 예측을 위해 필수적이다. 유출과정과 관련된 비선형성과 복잡성을 확인하기 위해 토양수분과 유출 사이의 이력 거동이 조사되었다. 특히, 수문 과정 내 이력 현상 구체화를 위해 정성적인 시각적 분류 및 정량적 평가를 위한 이력 지수들이 개발되었다. 정성적인 시각적 분류는 시간에 따라 시계 및 반시계방향으로 다중 루프 형상을 나누는 방식으로 진행되었고, 정량적 평가의 경우 이력 고리(Hysteretic loop) 내 상승 고리(Rising limb)와 하강 고리(Falling limb)의 차이를 기준으로 한 지수로 이력 현상을 특성화하였다. 이전에 제안된 방법론들은 연구자의 판단이 들어가기 때문에 보편적이지 않고 이력 현상을 개발된 지수에 맞춤에 따라 자료 손실이 나타나는 한계가 존재한다. 자료의 손실 없이 불포화대 내 발생 가능한 대표 이력 현상을 자동으로 추출하기 위해 적합한 비지도 학습기반 기계학습 방법론의 제안이 필요하다. 우리 연구에서는 국내 산지 사면에서 강우 사상 동안 다중 깊이(10, 30, 60cm)로 56개의 토양수분 측정지점에서 확보된 토양수분 시계열 자료와 산지 사면 내 위어를 통해 확보된 유출 시계열 자료를 사용하였다. 먼저, 기존에 분류 방법을 기반으로 계절 및 공간특성에 따라 지배적으로 발생하는 토양수분-유출 간 이력 현상을 특성화하였다. 다음으로, 토양수분-유출 간 이력 패턴을 자료 손실 없이 형상화하여 자동으로 데이터베이스화하는 알고리즘을 개발하였다. 마지막으로, 비지도 학습방법을 이용하여 데이터베이스화된 실제 발현 이력 현상 내 확률분포를 최대한 가깝게 추정하는 은닉층을 반복적인 재구성 학습을 통해 구현함으로써 대표 이력 현상 패턴을 추출하였다.

• Journal of IKEEE
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• v.28 no.1
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• pp.65-71
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• 2024

This paper proposes a neural network that can reduce the number of parameters while reducing matching errors in occluded regions to increase the accuracy of depth maps in stereo matching. Stereo matching-based object recognition is utilized in many fields to more accurately recognize situations using images. When there are many objects in a complex image, an occluded area is generated due to overlap between objects and occlusion by background, thereby lowering the accuracy of the depth map. To solve this problem, existing research methods that create context information and combine it with the cost volume or RoIselect in the occluded area increase the complexity of neural networks, making it difficult to learn and expensive to implement. In this paper, we create a depthwise seperable neural network that enhances regional feature extraction before cost volume generation, reducing the number of parameters and proposing a neural network that is robust to occlusion errors. Compared to PSMNet, the proposed neural network reduced the number of parameters by 30%, improving 5.3% in color error and 3.6% in test loss.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.3
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• pp.131-143
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• 2010

This paper investigates the history, policy and status of the conservation of historic gardens in the National Trust in England and its implications for Korea. It was conducted in three phases as follows: First, related literature data was collected to understand the National Trust and its role in the conservation of historic gardens. Second, The National Trust Policy Papers: Gardens and Landscape Parks in 1996 was reviewed and analyzed into eight categories with a review of 216 gardens and interviews with gardener-in-charge via e-mail. Finally an understanding of the policy for the conservation of historic gardens was formed from the results of the previous phases, and implications were drawn from the integrated analysis guidelines of the policy and status. The key feature of the conservation of the National Trust's historic gardens is that the conservation process has been conducted systematically through acquisition, management, upkeep, advice and so on. Furthermore, the conservation principles are defined in a concise and accessible form. According to their practical conservation process and principles, the results of the National Trust activities are to appreciate the significance of the gardens and act with accountability; integration; managing change; access and participation; and training gardener and partnership. According to the results of its activities under the premise that the purpose of the conservation and the meaning of a garden do not differ significantly among nations, implications for Korea can be primarily suggested by three points as follows: First of all, a flexible approach to change in historic gardens should be managed. In response to inevitable and desirable change, anything that is added or transferred should be recorded for the future as much as possible. Therefore, everything must be recorded and any change should be managed. Second, is to provide sustainable access for the benefit for the people and visitors. The aim of conserving the gardens is for human's to eventually understand that the present generation just borrows the historic gardens before they are passed down. The ensuing implication is that people may enjoy the gardens educationally, aesthetically, and physically, and children can be continuously interested in historic gardens as apart of educating the future generation. Finally, the National Trust educates apprentice gardeners who will maintain the historic gardens and continuously keep the current garden staff up to date with workshops. This is in contrast to the day laborers who work for historic gardens in Korea. In practice, the maintenance of historic gardens is not a simple process. The gardener must understand the past, reflect the present, and prepare for the future. Therefore, gardeners deliver culture from generation to generation.

• Journal of Korean Philosophical Society
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• no.116
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• pp.251-281
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• 2017

The Parmenidean tradition of logos which previous researches fail to fully appreciate has three dimensions of reality-knowledge-discourse. Parmenides is not just an ontologist, as the traditional view emphasizes, but also an epistemologist, as the revisionist view begins to emphasize, and, at the same time, a meta-discourser, as those two established views fail to embrace. In order to reach the third view which fully grasps such a dynamic and integrated feature of Parmenides, we should closely pay attention to the organic interconnectedness of three discourse parts of truth-doxa-proem, especially the significance of proem and meta-discourse. In the Eleatic tradition of discourse, the figure who clearly appreciated and further developed such an authentic feature of Parmenides' discourse is not, as one might easily expect, one of the second-generation Eleatics, but Gorgias who has commonly been positioned at the opposite side of Eleatism. This paper investigates how he actually both innovated and succeeded the Parmenidean tradition of logos; especially, it characterizes his discourse as an antilogy(antilogia) from within the tradition: as a 'devil' advocate' who complemented and completed Parmenidean persuasion by positing the Parmenidean tradition of logos as an arena of a huge intellectual discipline and cultivation, offering himself as a sparring partner to it, and bringing up an antilogy. In the process of this antilogy he performed in his rhetorical speeches such as the Encomium of Helen and the Defense of Palamedes he experimented and examined a possibility of persuasion operating independently from truth, which, however, is not merely sacrificing truth in favor of persuasiveness and probability (to eikos) as Plato criticized mainly focussing on his 'philosophical' writing On not-being. Rather, it was an 'opposition for opposition's sake' and serious play which purported to provide balance and flexibility to contemporary intellectual society which had too much inclined towards truth and knowledge and become stiff and to put weight on the opposite side of mainstream. It is wholly our eranos (i.e. our share of contribution) to summon and examine such sophistic tradition for the sake of the task of our times, not for the sake of Plato's task, that we should build up a healthy culture of discourse where we can share serious play.

• The KIPS Transactions:PartC
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• v.11C no.4
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• pp.509-518
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• 2004

Many simulators have been developed and are being used for the complex and various mobile communication service environments. Each of these simulators has its own teletraffic model that consists of traffic source model and network traffic model. In this paper, network traffic model and traffic source model, which are based on the data gathered in real environment, are defined in order to get more accurate simulation results in the mobile communication simulation for the urban region. The network traffic model suggested in this paper reflects the hourly call generation rate and call duration time by analyzing the data collected from actually installed base station by the time and place, and the traffic source model includes the delivery share ratio and average speed information in the region where the base station is installed. This paper defined and designed Mobile Host object that reflects the suggested traffic source model, and Call Generator object that reflects the network traffic model, and other objects support both objects. Using the teletraffic model suggested in the paper, user mobility similar to real service environment and traffic characteristics can be reflected on the simulation, and also more accurate simulation results can be got through that. In addition, by using object-oriented techniques, new service feature or environment can be easily added or changed so that the developed mobile communication simulator can reflect the real service environment all the time.

• Journal of the Korea Society of Computer and Information
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• v.25 no.9
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• pp.63-69
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• 2020

Image-image translation is a technology that creates a target image through input images, and has recently shown high performance in creating a more realistic image by utilizing GAN, which is a non-map learning structure. Therefore, there are various studies on image-to-image translation using GAN. At this point, most image-to-image translations basically target one attribute translation. But the data used and obtainable in real life consist of a variety of features that are hard to explain with one feature. Therefore, if you aim to change multiple attributes that can divide the image creation process by attributes to take advantage of the various attributes, you will be able to play a better role in image-to-image translation. In this paper, we propose Multi CycleGAN, a dual attribute transformation structure, by utilizing CycleGAN, which showed high performance among image-image translation structures using GAN. This structure implements a dual transformation structure in which three domains conduct two-way learning to learn about the two properties of an input domain. Experiments have shown that images through the new structure maintain the properties of the input area and show high performance with the target properties applied. Using this structure, it is possible to create more diverse images in the future, so we can expect to utilize image generation in more diverse areas.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.3 s.309
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• pp.67-75
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• 2006

Facial expressions exhibit not only facial feature motions, but also subtle changes in illumination and appearance. Since it is difficult to generate realistic facial expressions by using only geometric deformations, detailed features such as textures should also be deformed to achieve more realistic expression. The existing methods such as the expression ratio image have drawbacks, in that detailed changes of complexion by lighting can not be generated properly. In this paper, we propose a nonlinear model for skin color change and a model-based synthesis method for facial expression that can apply realistic expression details under different lighting conditions. The proposed method is composed of the following three steps; automatic extraction of facial features using active appearance model and geometric deformation of expression using warping, generation of facial expression using a model for nonlinear skin color change, and synthesis of original face with generated expression using a blending ratio that is computed by the Euclidean distance transform. Experimental results show that the proposed method generate realistic facial expressions under various lighting conditions.