• Journal of Software Assessment and Valuation
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• v.16 no.2
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• pp.9-23
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• 2020

Microsoft's Windows system is widely used as an operating system for the desktops and enterprise servers of companies or organizations, and is a major target of cyber attacks. Microsoft provides various protection technologies and strives for defending the attacks through periodic security patches, however the threats such as DLL injection and process injection still exist. In this paper, we analyze 12 types of injection techniques in Microsoft Windows, and perform injection attack experiments on four application programs. Through the results of the experiments, we identify the risk of injection techniques, and verify the effectiveness of the mitigation technology for defending injection attacks provided by Microsoft. As a result of the experiments, we have found that the current applications are vulnerable to several injection techniques. Finally, we have presented the mitigation techniques for these injection attacks and analyzed their effectiveness.

• Journal of Software Assessment and Valuation
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• v.17 no.1
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• pp.51-58
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• 2021

Microservices are not only developed independently, but can also be run and deployed independently, ensuring more flexible scaling and efficient collaboration in a cloud computing environment. This impact has led to a surge in migrating to microservices-oriented application environments in recent years. In order to introduce microservices, the problem of identifying microservice units in a single application built with a single architecture must first be solved. In this paper, we propose an algorithm-based approach to identify microservices from legacy systems. A graph is generated using the meta-information of the legacy code, and a microservice candidate is extracted by applying a clustering algorithm. Modularization quality is evaluated using metrics for the extracted microservice candidates. In addition, in order to validate the proposed method, candidate services are derived using codes of open software that are widely used for benchmarking, and the level of modularity is evaluated using metrics. It can be identified as a smaller unit of microservice, and as a result, the module quality has improved.

• Annual Conference of KIPS
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• 2020.05a
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• pp.365-367
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• 2020

현재 의료영상 진단검사는 간 질환의 진단을 위해 실제 임상에서 사용하고 있는 중요한 검사 방법이며 의료영상을 기반으로 한 정량분석 소프트웨어 개발 연구가 활발히 진행되고 있다. 특히, 의료영상을 기반으로 간 질환을 정량화 하는 방법 가운데 간 결절 점수와 간세포 이질성 점수를 이용하여 간질환에 대한 정량적 평가를 진행한 결과 간 결절 점수와 간세포 이질성 점수에 따른 간 질환 중증도의 상관관계가 증명되었으나 많은 문제점이 제기되었다. 의료영상에는 서로 상반되는 의료영상조건들을 가지고 있기 때문에 의료영상조건에 따른 영상처리 기술들이 필요하였으며 간 결절 점수와 간 세포 이질성 점수는 수식에 의한 계산법을 기반으로 산출하기 때문에 수식 결과에 대한 검증 과정이 필요하였다. 따라서, 본 연구는 기존의 문제점을 해결하기 위해 의료영상에 따른 의료영상처리 기술을 자동화 할 수 있도록 개발하였으며 간염, 간질환, 간 경변등 간 질환 중증도에 따른 정량적인 분석을 수행할 뿐만 아니라 분석 결과에 대한 리포트 결과까지 제공함으로써 간 질환을 진단하기 위한 정량적인 진단 지표가 될 수 있는 소프트웨어 기반의 간 질환 진단 기술을 제안하고자 한다.

• Journal of Software Assessment and Valuation
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• v.15 no.1
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• pp.71-78
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• 2019

Lasers for optical broadband communication systems should have excellent frequency selectivity and modal stability. DFB lasers have low lasing frequency shift during high speed current modulation. In this paper, we have developed a simulation software and analysed beam profiles of a lasing mode in longitudinal direction of an 1.55um DFB laser with two mirrors and without anti-reflection coatings, that have both an index- and gain-gratings. As the phases of the index and gain gratings on the mirror faces are varied, the beam profiles |R(z)| and |S(z)| of the lasing mode with the emitted power ratio P_l/p_r are analysed and examined. In order to reduce the threshold current of a lasing mode and enhance the frequency stability, κL should be greater than 8, regardless of the grating phases on the mirror faces.

• Journal of the Korea Computer Graphics Society
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• v.30 no.1
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• pp.11-17
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• 2024

Lung cancer segmentation in chest CT images is challenging due to the varying sizes of tumors and the presence of surrounding structures with similar intensity values. To address these issues, we propose a lung cancer segmentation network that incorporates deep supervision and utilizes UNet3+ as the backbone. Additionally, we propose a hybrid lesion focal loss function comprising three components: pixel-based, region-based, and shape-based, which allows us to focus on the smaller tumor regions relative to the background and consider shape information for handling ambiguous boundaries. We validate our proposed method through comparative experiments with UNet and UNet3+ and demonstrate that our proposed method achieves superior performance in terms of Dice Similarity Coefficient (DSC) for tumors of all sizes.

• The Journal of the Acoustical Society of Korea
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• v.25 no.2
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• pp.61-71
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• 2006

An MP3 encoder chip has been designed and fabricated with the hardware and software co-design concepts. In the aspect of the software. the calculation cycles of the distortion control loop. which requires most of the calculation cycles in MP3 encoding procedure. have been reduced to $67\%$ of the original algorithm through the 'scale factor Pre-calculation'. By using a floating Point 32 bit DSP core and designing the FFT block with the hardware. we can get the additional reduction of the calculation cycles in addition to the software optimization. The designed chip has been verified using HW emulation and fabricated via 0.25um CMOS technology The fabricated chip has the size of $6.2{\time}6.2mm^2$ and operates normally on the test board in the qualitative and quantitative aspect.

• Journal of Aerospace System Engineering
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• v.18 no.4
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• pp.18-26
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• 2024

This paper describes the results of a study on Generic Quad Tilt Rotor UAM aircraft, focusing on nonlinear mathematical modeling and the development of real-time simulation software. In this research, we designed a configuration for a Generic Quad Tilt Rotor eVTOL UAM aircraft based on NASA's UAM mission requirements. We modeled the aerodynamics using a database, the prop-rotor dynamics with a thrust database, and included a ground reaction and atmospheric model in the flight model. We defined the control concept for various modes(helicopter mode, transition mode, and airplane mode), derived tilt angle corridors, and formulated flight control requirements. The resultant real-time flight simulation software not only performs trim analysis for Tilt Rotor UAM aircraft but also predicts handling qualities, optimizes tilt angle scheduling based on dynamic characteristics, designs and validates flight control laws for helicopter, transition, and airplane modes, and facilitates flight training through simulator integration.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.339-350
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• 2003

Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For. the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL) CBS simulator(CBSSIM) was also developed. We assumed that the spacecraft platform for the CBSSIM is a geostationary communication satellite using momentum bias three-axis stabilization control technique based on Koreasat. The payload hardware is combined with CBSSIM via Power, Command and Telemetry System(PCTS) of Electrical Ground Support Equipment(EGSE). CBSSIM is connected with PCTS by TCP/IP and the payload is combined with PCTS by MIL-STD-1553B protocol and DC harness. This simulator runs under the PC-based simulation environment with Windows 2000 operating system. The satellite commands from the operators are transferred to the payload or bus subsystem models through the real-time process block in the simulator. Design requirements of the CBSSIM are to operate in real-time and generate telemetry. CBSSIM provides various graphic monitoring interfaces and control functions and supports both pre-launch and after-launch of a communication satellite system. In this paper, the HITL simulator system including CBSSIM, communications payload and PCTS as the medium of interface between CBSSIM and communications payload will be described in aspects of the system architecture, spacecraft models, and simulator operation environment.

• Journal of KIISE
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• v.42 no.4
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• pp.459-467
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• 2015

The analysis platform of remote-sensing big data is a system that downloads data from satellites, transforms it to a data type of L3, and then analyzes it and produces its analysis results. The objective of this paper is to develop ISO/IEC 9126-1 software quality model-based assessment criteria, in order to evaluate the quality of remote-sensing big data analysis platform. Its detailed research contents are as follows. First, the ISO/IEC 9216 standards and previous software evaluation models will be reviewed. Second, this paper will define evaluation areas, evaluation elements, and evaluation items for measuring the quality of big data analysis platform. Third, the validity of the assessment criteria will be verified by statistical experiments through content validity, reliability validity, and construct validity, by using SPSS 20.0 and Amos 20.0 software. The construct validity will also be conducted by performing the confirmatory factor analysis and path analysis. Lastly, it is significant that our research result demonstrates the first evaluation criteria in measuring the quality of big data analysis platform. It is also expected that our assessment criteria could be used as the basis information for evaluation criteria in the platforms that will be developed in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.205-213
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• 2018

Development and validation of crop models often require measurements of biomass for the crop of interest. Considerable efforts would be needed to obtain a reasonable amount of biomass data because the destructive sampling of a given crop is usually used. The Kinect sensor, which has a combination of image and depth sensors, can be used for estimating crop biomass without using destructive sampling approach. This approach could provide more data sets for model development and validation. The objective of this study was to examine the applicability of the Kinect sensor for estimation of chinese cabbage fresh weight. The fresh weight of five chinese cabbage was measured and compared with estimates using the Kinect sensor. The estimates were obtained by scanning individual chinese cabbage to create point cloud, removing noise, and building a three dimensional model with a set of free software. It was found that the 3D model created using the Kinect sensor explained about 98.7% of variation in fresh weight of chinese cabbage. Furthermore, the correlation coefficient between estimates and measurements were highly significant, which suggested that the Kinect sensor would be applicable to estimation of fresh weight for chinese cabbage. Our results demonstrated that a depth sensor allows for a non-destructive sampling approach, which enables to collect observation data for crop fresh weight over time. This would help development and validation of a crop model using a large number of reliable data sets, which merits further studies on application of various depth sensors to crop dry weight measurements.