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Filtering-Based Method and Hardware Architecture for Drivable Area Detection in Road Environment Including Vegetation (초목을 포함한 도로 환경에서 주행 가능 영역 검출을 위한 필터링 기반 방법 및 하드웨어 구조)

  • Kim, Younghyeon;Ha, Jiseok;Choi, Cheol-Ho;Moon, Byungin
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.1
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    • pp.51-58
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    • 2022
  • Drivable area detection, one of the main functions of advanced driver assistance systems, means detecting an area where a vehicle can safely drive. The drivable area detection is closely related to the safety of the driver and it requires high accuracy with real-time operation. To satisfy these conditions, V-disparity-based method is widely used to detect a drivable area by calculating the road disparity value in each row of an image. However, the V-disparity-based method can falsely detect a non-road area as a road when the disparity value is not accurate or the disparity value of the object is equal to the disparity value of the road. In a road environment including vegetation, such as a highway and a country road, the vegetation area may be falsely detected as the drivable area because the disparity characteristics of the vegetation are similar to those of the road. Therefore, this paper proposes a drivable area detection method and hardware architecture with a high accuracy in road environments including vegetation areas by reducing the number of false detections caused by V-disparity characteristic. When 289 images provided by KITTI road dataset are used to evaluate the road detection performance of the proposed method, it shows an accuracy of 90.12% and a recall of 97.96%. In addition, when the proposed hardware architecture is implemented on the FPGA platform, it uses 8925 slice registers and 7066 slice LUTs.

A Study on Curriculum Analysis and Awareness of the Development of Standard Curriculum for Library Information Science in Korea (국내 문헌정보학 표준교육과정 개발을 위한 교과과정 분석 및 인식 조사 연구)

  • Jang, Su Hyun;Park, Sang Uk;Nam, Young Joon
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.33 no.1
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    • pp.199-232
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    • 2022
  • The purpose of this study is to propose considerations prior to the development of a standard curriculum for Library and Information Science that secures the objectivity and reliability of the curriculum nationally. To this end, first, the Ministry of Culture, Sports and Tourism's notification related to NCS job units and librarian qualification standards in the field of Library and Information Science was reviewed. Second, The current status was investigated and analyzed by investigating and analyzing the courses opened in Library and Information Science nationwide. Third, surveys and focus interviews were conducted on librarians and information experts. The implications from the analysis results are as follows. Among the Library and Information Science departments opened in 2021, the field with the highest number of subjects was "information service," and it was confirmed that the most frequently derived keyword was "information." The survey results were analyzed through IPA analysis and Borich demand analysis, and the top priority required subjects for each grade were derived. As a result of investigating the opinions of librarians and information experts in the field through surveys and focus interviews, it was confirmed that Korean Library and Information Science education should be conducted not only in standardization but also in parallel with the operation of specialized subjects that can cover various users.

Analysis of Eddy Current Loss on Permanent Magnets of Interior Permanent Magnet Synchronous Motor for Railway Transit (철도차량용 매입형 영구자석 동기전동기의 영구자석 와전류 손실 분석 연구)

  • Park, Chan-Bae;Lee, Hyung-Woo;Lee, Byung-Song
    • Journal of the Korean Society for Railway
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    • v.15 no.4
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    • pp.370-375
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    • 2012
  • In order to apply Interior Permanet Magnet Synchronous Motor(IPMSM) to the propulsion system of the railway transit, 110kW class IPMSMs with high-power density are designed as a concentrated winding model and a distributed winding model in this study. The concentrated winding model designed in this study is 6 poles/9 slots and the distributed winding model is 6 poles/36 slots. In general, the eddy current losses in the permanent magnets of IPMSM are caused by the slot harmonics. The thermal demagnetization of the magnet by the eddy current losses at high rotational speed often becomes one of the major problems in the IPMSM with a concentrated windings especially. A design to reduce eddy current losses in permanent magnet design is important in IPMSM for the railway vehicle propulsion system which requires high-speed operation. Therefore, a method to devide the permanent magnet is proposed to reduce the eddy current losses in permanent magnet in this study. Authors analyze the variation characteristics of the eddy current losses generated in permanent magnet of the concentrated winding model by changing the number of the division of the permanent magnets.

The 'One Belt One Road' Initiative and Development of Inland Port in China (중국 '일대일로' 이니셔티브와 내륙항의 발전)

  • Lee, Choong Bae;Lee, Jong Chul
    • Journal of Korea Port Economic Association
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    • v.33 no.3
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    • pp.1-16
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    • 2017
  • China has achieved rapid economic growth in the late 1970s with economic reform and open-door policy. China's economic growth began initially in the eastern coastal areas and from the 2000s expanded to the western and northeastern regions where the economy was relatively underdeveloped. In particular, in 2013 'One-Belt One Road' initiative proposed by Xi Jinping, the current General Secretary of the Communist Party of China is not only a key strategy for China's advancement into the world and also provides important opportunities for the development of these backward regions. Inland Port is the inland logistics hub and plays a crucial role in enhancing access to maritime ports as well as access to adjacent inland countries. Therefore, a number of inland ports have been developed and operated in order to enter into overseas markets and secure resources in the northeastern and western regions of China. This study aims to examine the role and development of inland port in 'One-Belt One Road' scheme. In conclusion, 'One-Belt One Road' will further increase the role of inland port, and in response, the development of inland port will play a pivotal role in one belt one road initiative. In this respect, Korean companies need to consider plans to participate in the development and operation of inland ports in China, which would provide opportunities to spread Northern markets including China, Russia, Central Asia, Eastern Europe.

2N-Point FFT-Based Inter-Carrier Interference Cancellation Alamouti Coded OFDM Method for Distributed Antennas systems (분산안테나 시스템을 위한 2N-점 고속푸리에변환 기반 부반송파 간 간섭 자체제거 알라무티 부호화 직교주파수분할다중화 기법)

  • Kim, Bong-Seok;Choi, Kwonhue
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.12
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    • pp.1030-1038
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    • 2013
  • The proposed Alamouti coded OFDM effectively cancels Inter Carrier Interference (ICI) due to frequency offset between distributed antennas. The conventional Alamouti coded OFDM schemes to mitigate ICI utilize N-point Inverse Fast Fourier Transform/Fast Fourier Transform (IFFT/FFT) operations for OFDM modulation and demodulation processes with total N subcarriers. However, the performance degrades because ICI is also repeated in N periods due to the property of N-point IFFT/FFT operation. In order to avoid this problem, null data are used at the subcarriers with large ICI and thus, data rate decreases. The proposed scheme employs 2N-point IFFT/FFT instead of N-point IFFT/FFT in order to increase sampling rate. By increasing sampling rate, the amount of interference significantly decreases because the period of ICI also increases. The proposed scheme increases the data rate and improves the performance by reducing amount of ICI and the number of null-data. Furthermore, the gain of the performance and data rate of the proposed scheme is significant with higher modulation such as 16-Quadarature Amplitude Modulation (QAM) or 64-QAM.

A Case Study on SK Telecom's Next Generation Marketing System Development (SK텔레콤의 차세대 마케팅 시스템 개발사례 연구)

  • Lee, Sang-Goo;Jang, Si-Young;Yang, Jung-Yeon
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.2
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    • pp.158-170
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    • 2008
  • In response to the changing demands of ever competitive market, SK Telecom has built a new marketing system that can support dynamic marketing campaigns and, at the same time, scale up to the large volumes of data and transactions for the next decade. The system which employs Unix-based client-server (using Web browser interfaces) architecture will replace the current mainframe-based COIS system. The project, named NGM (Next Generation Marketing ), is unprecedentedly large in scale. However, both managerial and technical problems led the project into a crisis. The application framework that depended on a software solution from a major global vendor could not support the dynamic functionalities required for the new system. In March 2005, SK telecom declared the suspension of the NGM project. The second phase of the project started in May 2005 following a comprehensive replanning. It was decided that no single existing solution could cope with the complexity of the new system and hence the new system would be custom-built. As such. a number of technical challenges emerged. In this paper, we report on the three key dimensions of technical challenges - middleware and application framework, database architecture and tuning, and system performance. The processes and approaches, adopted in building NGM system, may be viewed as "best practices" in the telecom industry. The completed NGM system, now called "U.key System," successfully came into operation on the ninth of October, 2006. This new infrastructure is expected to give birth to a series of innovative, fruitful, and customer-oriented applications in the near future.

Thermal and Flow Analysis of a Driving Controller for Active Destruction Protections (능동 파괴 방호 구동제어기의 열 유동 해석)

  • Ryu, Bong-Jo;Oh, Bu-Jin;Kim, Youngshik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.2
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    • pp.235-242
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    • 2017
  • A driving controller for active destruction protections can be applied to machinery, aerospace and military fields. In particular, this controller can be used to track and attack enemy flying objects through the active control. It is important to ensure reliability of the driving controller since its operation should be kept with precision to the target point. The temperature of the environment where the driving controller is used is about -32 C ~ 50 C (241~323 ). Heat generated in the driving controller should be maintained below a certain threshold (85 C (358 )) to ensure reliability; therefore, the study and analysis of the heat flow characteristics in the driving controller are required. In this research, commercial software Solid-Works Flow Simulation was used for the numerical simulation assuming a low Reynolds number turbulence model and an incompressible viscous flow. The goal of this paper is to design the driving controller safely by analyzing the characteristics of the heat flow inside of the controller composed of chips or boards. Our analysis shows temperature distributions for boards and chips below a certain threshold.

Efficiency analysis of the community welfare centers for people with disabilities using data envelopment analysis (자료포락분석을 활용한 장애인복지관의 효율성 분석)

  • Choi, Kyoungho;Shin, Hyun-Uk
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.1
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    • pp.111-121
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    • 2015
  • Until now, the operation of community welfare centers for people with disabilities has brought a positive or a generous awareness. Nevertheless, in order to obtain a wide range of welfare outcomes efficiently, the imperative step in rehabilitation researches is to determine whether reasonable and scientific services are being provided to people with disabilities in rehabilitation centers. The purpose of this study was to analyze efficiency and productivity of 176 community welfare centers for people with disabilities. As a result, average technical efficiency for community welfare centers for people with disabilities was 0.4488; pure technical efficiency and scale efficiency was 0.6040 and 0.7080, respectively. The major conclusions of this study were as follows. First, applying the technical efficiency analysis, DMU2, DMU3, DMU8, DMU9, DMU11, DMU13, DMU14 were shown above average. It seems to have a regard for political elements in accordance with the regional social and economic differences. Second, as a result of scale efficiency analysis, the inefficient community welfare centers for people with disabilities such as DMU1, DMU5, DMU12, DMU16 are required to improve the number of employees, revenue, facility area. Finally, this study is expected to be an effectiveness analysis and performance evaluation for the rehabilitation services.

A case of two sisters births from mother with phenylketonuria lacking mental retardation (정신 지체가 아닌 페닐케톤뇨증 산모에서 출생한 자매 1례)

  • Ki, Chang-Seok;Kim, Jin Kyung
    • Clinical and Experimental Pediatrics
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    • v.51 no.5
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    • pp.546-550
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    • 2008
  • In this untreated classic phenylketonuria (PKU) case, mental retardation is severe; however, there have been individuals- like the mother of this case- who have escaped mental retardation and all the other potential sequelae of phenylketonuria, despite having high blood phenylalanine levels, and very poor dietary control. It appears that they have nearly normal brain phenylalanine levels despite high blood phenylalanine (Phe) levels. A number of studies have now demonstrated considerable variability in blood vs. brain phenylalanine levels in phenylketonuria patients. Outcome of phenylketonuria appears to be related to brain phenylalanine levels. We report a case of "undiagnosed" maternal phenylketonuria syndrome. A female infant had low birth weight (2,400 g) with microcephaly. We examined her family and discovered that her mother was an undiagnosed phenylketonuria patient with a borderline intelligence quotient (IQ). The infant's sister, six years old, was diagnosed with phenylketonuria at the age of four years was mentally retarded and had received an operation for cleft lip and palate. the sister had also had a low birth weight (2,300 g). Her sister and mother were compound heterozygotes (mother: R243Q/Y325X; sister: Y325X/P407S). The infant and father were heterozygous carriers (baby: R243Q/ -; father: P407S/ - ).

Performance Evaluation of Magnesium Bipolar Plate in Lightweight PEM Fuel Cell Stack for UAV (무인기용 경량 PEM 연료전지 스택용 마그네슘 분리판의 성능평가)

  • Park, To-Soon;Oh, Ji-Hyun;Ryu, Tae-Kyu;Kwon, Se-Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.10
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    • pp.788-795
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    • 2013
  • A magnesium bipolar plate whose surface was protected by thinly deposited silver layer was investigated as an alternative to existing graphite bipolar plate of PEM fuel cells. Thin silver layer of $3{\mu}m$ was deposited on a magnesium alloy substrate by physical vapor deposition (PVD) method in an environment of $180^{\circ}C$. A number of tests were conducted on the fabricated magnesium based bipolar plates to determine their suitability for use in PEM fuel cell stacks. The test on corrosion resistance in the same pH condition as in a PEM operation demonstrated the layer protected the magnesium alloy substrate, while unprotected substrate suffered from severe corrosion. The contact resistance of the fabricated bipolar plate was less than $20m{\Omega}-cm^2$ which was superior to the conventional bipolar plates. A single cell was constructed using the fabricated bipolar plates and power output was measured. Due to the enhanced conductivity caused by low contact resistance, slight increase was observed in current density and output voltage. With low density of the magnesium substrate and ease on machining, the weight reduction of the stack of 30~40 % is possible to produce the same power output.