• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.3
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• pp.643-652
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• 2000

In this paper, we analyze the BER performance of OFDM/QPSK system in frequency selective Rayleigh fading channel with impulsive noise and improve its performance by adopting convolutional coding. When the channel delay time is shorter than the guard band, the OFDM/QPSK system shows a good BER performance while, when the channel delay time becomes longer than the guard band, its BER performance is abruptly degraded. Moreover, when the transmitted signal is contaminated by a strong impulsive noise in the channel, the BER performance falls to about $10^{-1}$. Also, without channel coding technique, the system doesn't meet even the voice service requirement while it meets the data service requirement with convolutional coding in frequency selective Rayleigh fading channel with impulsive noise.

• Journal of Korea Trade
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• v.26 no.8
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• pp.58-76
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• 2022

Purpose - This study examined the Rules of Origin (RoO) as a factor affecting free trade agreements' (FTA) utilization and analyzed the causal relationship and the effects of these factors on the export performance of automobile parts companies. Design/methodology - We analyzed and verified the impact of FTA utilization and the export performance of automobile parts companies by dividing the characteristics of the RoO into complexity and uncertainty. Following which, various statistical analyses were conducted on the interrelationships among these variables. Findings - This research analyzed the effect of the RoO factors of complexity and uncertainty on the use of FTA and the export performance of automobile parts companies. We found that these characteristics of RoO were generally related to and affected the FTA use and export performance of these companies. Based on this, this study's investigation into the characteristics of the RoO would then help companies in better utilizing the FTA, as well as providing suggestions on how to effectively respond to the application of the FTA in the future. Originality/value - Companies that want to utilize FTAs in international trade must follow the RoO. In the Regional Trade Agreement (RTA), the country-of-origin is a key factor, with the RoO being an important requirement for the application of preferential tariffs. These regulations are a requirement for receiving FTA preferential treatment; however, they also cause difficulties to companies in using the FTA.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.471-480
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• 2022

This experiment was conducted to determine the maximum dietary energy levels on growth performance and carcass characteristics of White Pekin duck. the Six dietary treatments were formulated based on their apparent metabolizable energy (AME) concentrations from 2,700 to 3,200 kcal/kg with a 100 kcal/kg gap to evaluate the accurate dietary AME requirement to address current knowledge and further issues for fulfilling the genetic potential of meat-type white Pekin ducklings. A total of 432 one-day-old male White Pekin ducklings were randomly allocated into one of six dietary treatments with six replicates (12 birds per pen). The diets were formulated as corn-soybean meal-based diets to meet or exceed the Nutrient Requirement of Poultry specification for meat-type ducks. Growth performance indices (i.e. average daily gain [ADG], average daily feed intake, feed conversion ratio) were measured weekly. Medium body weight (BW) ducklings from each pen were sacrificed to analyze the carcass traits and abdominal fat content on day 21. Obtained data were analyzed to estimate significant effect using the one-way ANOVA of IBM SPSS Statistics (Version, 25). If the p-value of the results were significant, differences in means among treatments were separated by Tukey's post hoc test. Significant differences were then analyzed with a linear and quadratic broken model to estimate the accurate concentration of AME. Ducklings fed higher dietary AME diets increased (p < 0.05) BW, ADG. Ducklings fed higher AME than 2,900 kcal/kg diets increased abdominal fat accumulation and leg meat portion. The estimated requirement by linear plateau method showed from 3,000.00 kcal/kg to 3,173.03 kcal/kg whereas the requirement by quadratic plateau method indicated from 3,100.00 kcal/kg to 3,306.26 kcal/kg. Collectively, estimated dietary requirements exhibit diverse results based on the measured traits and analysis methods. All the estimated requirements in this experiment present higher than previous research, the maximum requirement for the next diet formulation should be selected by the purpose of the diet.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1523-1529
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• 2011

Light Rail Transit is system that offer target Performance and function because various sub-system such as vehicles, power supply, signaling, communication, mechanical, track, civil is consisted as large complex system. Light Rail Transit and the complex system of safety, reliability to be a behavior, and target performance and function properly to system's configuration, design, manufacture, installation and test verification, through operations system requirements to accurately describe what It is more important. With this study, light rail system KSX ISO/IEC 15288 system life cycle process by applying engineering techniques utilizing light rail system in the early stages of construction from the concept, design, production, operation, maintenance and end-use to the disposal stage throughout the entire life cycle, from the beginning of construction until the end of construction of the stakeholder to define requirements, analyze the introduction of the system developers and system requirement of those who wish to be described accurately by selecting the best system and system requirement in order to achieve their purpose.

• Journal of the Earthquake Engineering Society of Korea
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• v.17 no.6
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• pp.271-278
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• 2013

The hysteretic behavior of diagonal reinforced coupling beams is excellent during earthquakes. However, construction of the diagonal reinforced coupling beams is difficult due to complex reinforcement details required by current code procedures (ACI 318-11). Due to the detail requirement, reinforcement congestion and interference among transverse reinforcement always occur during construction field. When the aspect ratio of the beam is large, the interference of reinforcement becomes more serious. The objective of this paper is to simplify the reinforcement details of slender coupling beams by reducing transverse reinforcement around the beam perimeter. For this purpose, high- performance fiber reinforced cementitious composites are used for making coupling beams. Experiments were conducted using three specimens having aspect ratio 3.5. Test results showed that HPFRCC coupling beams with half the transverse reinforcement required by ACI 318-11 provided identical seismic capacities to the corresponding coupling beams having requirement satisfying the requirement specified in ACI 318-11.

• Journal of Korean Home Economics Education Association
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• v.15 no.4
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• pp.23-35
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• 2003

The purpose of this research is to analyse the composition of theories and practical activities in clothing and textiles in Technologyㆍ Home economics textbooks in the 7th National Curriculum and find out learning requirement of students in the area. For this research, a survey was conducted using questionnaires with 280 high school students living in Daegu and the rate of response was 78.9%. The results of this study are as follows. 1. After analysing the curriculum of Practical Arts subject in elementary school and Technology´ Home Economics subject in secondary school, we could find out that more emphasis is put on practical activities in elementary school and high school. On the other hand, theories are considered more important in middle school. 2. Students have similar preference both for theories and for practical activities as a way of learning in class and show positive responses to practical activities unless they´re giving too much pressure as a part of performance test. 3. According to their learning requirement. several teaching-learning contents in clothing and textiles in Technology Home economics are selected such as materials,. clothes designs, how to set dressed well, how to make a reasonable purchase on clothes, and the process of manufacturing various clothes, etc. Therefore it would be desirable to provide the students with the learning opportunity to the extent where even the students who haven´t chosen the selected-advanced course can take part in class actively.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.779-782
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• 2004

Establishing and maintaining optimum lamp operating temperature is critically important in backlight systems for large area displays. The information presented in this paper is based upon work completed for a tiled 37.5" AM LCD, plus projections for a 37.5", 42" & 50" monolithic display. Due to the size of the units, a requirement for highly collimated light and a requirement for high brightness, >550 nits at the display surface, significant wattage is required which generates high heat levels in the backlight display assembly and potentially, at the display rear surface. Uniformity of illumination becomes an important element in the system design because of the large area involved.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.472-475
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• 2009

Nowadays, Short headway is a requirement of Signaling System applied to subway and Light Rail Transit (LRT) being constructed in Korea. To satisfy this Systematic Requirement, the accuracy of train position information on the line is one of the main element to improve ATC system safety and performance. On-board ATC system performs feasibility of Train Position as comparing data from balise installed along the track with data from tachometer installed at both axles of train.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.04a
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• pp.21-21
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• 1998

추력방향 제어시스템 설계에 있어서 가장 기본적으로 요구되는 Requirement는 Rocket Motor의 추력, 요구되는 최대 Side Force, Rocket Motor의 외경, System의 총 구동시간, 구동후의 분리여부 등이다. 이러한 Requirement를 만족하기 위해서는 Nozzle 출구의 분출가스 물성치로부터 초음속 유동해석을 통하여 Vane 주위의 속도, 온도, 압력 분포를 구하고, Vane의 받음각 변화에 대한 Aerodynamic Force와 Moment를 계산하고, Side Force를 만족하는 최대 받음각의 결정, Torque를 만족하는 감속기와 Motor의 선정 및 Housing 기본 형상을 설계하였다. 금번 개발에서는 지상 시험용으로서 안전 계수를 Flight Model보다 약간 높게 설계하였으며, 작동 완료 후 System이 Nozzle로부터 떨어져나가는 분리시스템은 포함하지 않았다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.3
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• pp.247-253
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• 2013

This paper analyzes ship area network(SAN) with integrated gateway. For the analysis, this paper analyzes reference network architecture, end-to-end connection model, traffic model, and requirement of SAN. Also, the type of network element and minimum performance of integrated gateway is derived by ship area network simulator. The performance evaluation results show that a integrated gateway operating as network switch with performance over than 30,000 packets/sec can provides end-to-end connection with satisfaction of requirement of each end-to-end connection.