• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.513-516
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• 2000

In this paper, we investigate the effect of the retransmission limit both the system capacity and the average number of retransmissions in a voice/data DS-CDMA system. Basically, we consider the IS-95 type reverse link of the CDMA system, which supports two kinds of services: a general voice and a packetized data service. ARQ is used for the reliable data transmission. Convolutional code is used for FEC and CRC-CCITT code is used for the error detection in ARQ. The result shows that the number of concurrent data users decreases as we reduce the number of the retransmissions. However, at the same time, we can also reduce the average number of retransmissions. Concluding1y, we can select the retransmission limit so as to reduce large amount of' retransmissions with small sacrifice in the system capacity.

• International Journal of Advanced Culture Technology
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• 제7권1호
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• pp.133-142
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• 2019

This study aims to understand how different construction methods impact scenic preference of green wall and clarify features of each construction method to help select the most suitable construction method for the wanted image of a green wall by providing the basic data for further development and distribution of green wall. Questionnaire developed by the Repertory Grid technique proved that 11 adjectives can be used to describe scenic features of a green wall and 4 preference elements. The result of the Scenic evaluation, the Felt type scored high in 'Aesthetic' and 'Maintenance' meaning that it is the most suitable method when constructing a green wall to improve urban scenery. Regression analysis was conducted to understand the link between the preference elements and scenic impression of a green wall. The result is that the higher the preference is on the design of a green wall, the higher the score is for 'Aesthetic'. Also, the higher the preference is on Bio-Diversity, Design, Growth, the higher the score is for 'Natural'. The above findings can be important measures and reference for selection of the right construction method when planning a green wall.

• 한국멀티미디어학회논문지
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• 제8권1호
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• pp.119-127
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• 2005

국내의 많은 대학들은 매년 교육전산망에서 망 서비스 업자를 공개 입찰로 선정한 결과에 따라 교내망을 자신에 맞게 다양한 방법으로 외부망과 연결시키고 있다 그런데 이들 중 특히, 여러 외부망을 연동시키는 대학에서는 연동 비율에 따라서 전산망 운영 방식을 결정하는데 있어 보다 복잡한 문제에 부딪치고 있다. 따라서 이러한 대학들은 자신의 전산망 운영 방식을 보다 적합하게 결정할 수 있는 지원체계가 시급하다. 본 논문은 전국의 대학전산망 운영자를 대상으로 한 트래픽 관리에 대한 설문조사를 바탕으로 하여 회선 이용율에 기반한 트래픽 효율성을 분석하였다. 그리고 이를 이용하여 두 사업자를 동시에 채택하고 있는 대학의 효율적인 외부망 연동 전략 방안을 제시한다.

• 대한전자공학회논문지TC
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• 제49권5호
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• pp.66-71
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• 2012

이동성이 있는 센서 노드나 매우 제한된 에너지 량을 사용할 수 있는 배터리 용량을 가진 센서 노드는 채널의 변화나 미세한 이동이 있더라도 정확한 네트워크 구성을 할 수 있어 한다. 본 논문에서는 무선 센서 네트워크 내에서 다수의 협동 릴레이 노드가 존재할 때 선택기준에 따라 SNR(Signal to Noise Ratio)과 릴레이 노드의 신호 증폭률 그리고 단말과 단말 간 직접적으로 통신하는 경우 경로의 이득의 변화에 따른 무선 센서네트워크의 단위 비트를 전송하는데 소모되는 에너지 효율에 대하여 분석하고 이에 따른 영향을 정량적으로 평가하였다. 전송용량의 이득과 에너지 소모에 있어서 이득이 있는 협동 릴레이 노드를 선택하여 직접 경로와 릴레이 경로의 복수의 경로를 사용함으로써 위상 비동기 협동 릴레이를 적용하는 센서네트워크 환경하에서 직접적으로 통신하는 경우대비 적은 에너지를 사용하여 무선 센서 네트워크 내에서 효율적으로 통신이 이루어 질 수 있음을 분석을 통해 확인하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권4호
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• pp.1317-1341
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• 2021

Nowadays, the Internet of Things (IoT) is adopted to enable effective and smooth communication among different networks. In some specific application, the Wireless Sensor Networks (WSN) are used in IoT to gather peculiar data without the interaction of human. The WSNs are self-organizing in nature, so it mostly prefer multi-hop data forwarding. Thus to achieve better communication, a cross-layer routing strategy is preferred. In the cross-layer routing strategy, the routing processed through three layers such as transport, data link, and physical layer. Even though effective communication achieved via a cross-layer routing strategy, energy is another constraint in WSN assisted IoT. Cluster-based communication is one of the most used strategies for effectively preserving energy in WSN routing. This paper proposes a Bio-inspired cross-layer routing (BiHCLR) protocol to achieve effective and energy preserving routing in WSN assisted IoT. Initially, the deployed sensor nodes are arranged in the form of a grid as per the grid-based routing strategy. Then to enable energy preservation in BiHCLR, the fuzzy logic approach is executed to select the Cluster Head (CH) for every cell of the grid. Then a hybrid bio-inspired algorithm is used to select the routing path. The hybrid algorithm combines moth search and Salp Swarm optimization techniques. The performance of the proposed BiHCLR is evaluated based on the Quality of Service (QoS) analysis in terms of Packet loss, error bit rate, transmission delay, lifetime of network, buffer occupancy and throughput. Then these performances are validated based on comparison with conventional routing strategies like Fuzzy-rule-based Energy Efficient Clustering and Immune-Inspired Routing (FEEC-IIR), Neuro-Fuzzy- Emperor Penguin Optimization (NF-EPO), Fuzzy Reinforcement Learning-based Data Gathering (FRLDG) and Hierarchical Energy Efficient Data gathering (HEED). Ultimately the performance of the proposed BiHCLR outperforms all other conventional techniques.

• 한국운동역학회지
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• 제14권2호
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• pp.1-14
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• 2004

This study was intended to contribute to allowing athletes to raise a technical understanding of two motions of high difficulty such as the Swallow motion and the Nakayama motion and enhance their competitive power by analysing the kinematical factors required to link those two motions on the competitive scene on the rings for current national athletes. For this purpose, the game of the ring event was videotaped for male heavy gymnasts participating in the final elimination match of the 2004 Athens Olympic Games. This study attempted to select the performing motions of the final 1st-and 2nd-place athletes performing the linking motions from the Swallow motion and the Nakayama motion using the DLT(direct linear transformation) method. As a result, it arrived at the following conclusion : A1 properly performed the flexing and extending movements using the angular velocity of the segment and joint as the switching motion using the body at the time of linking the motion from the Swallow skill to the Nakayama skill. A2 was evaluated to perform the skill taking the form of depending on the force at the static state. Therefore, it is thought that A1 should take care of shaking at the time of using the elasticity of the body. It is thought that in case of A2 the proper use of the elasticity of the body take care of shaking at the switching motion while taking advantage of the force will contribute to his competitive power.

• 한국통신학회논문지
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• 제11권1호
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• pp.25-39
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• 1986

본 논문에서는 packet switching network의 국제 표준 접속 protocol인 CCITT X.25 protocol의 성능을 분석하며 특히 X.25 protocol의 유통 제어 방식에 대하여 분석한다. Protocol의 성능 분석은 normalized channel throughput, mean transmission time과 transmission efficiency를 사용하면 이들은 window 크기, $T_1$ 및 $T_2$ 값 그리고 message길이 등과 같은 주어진 protocol parameter의 함수로 표시된다. 먼저 protocol 서비스에 따른 입력 데이타의 서비스 특성과 piggybacked acknowledgment를 하는 sliding window flow control 방식에 대하여 discrete-time Markov chain을 사용하여 연구한다. Protocol의 성능은 link layer 및 packet layer 에 대하여 각기 독립적으로 분석하며 분석결과를 통하여 각 protocol parameter의 영향을 조사한다. 수치적인 분석 결과로 부터 채널 서비스 환경에 따른 protocol parameter의 최적치를 찾을 수 있는데 window크기는 고속채널의 경우 7이상이 되는 것이 바람직 하며, $T_1$ timer 값은 채널의 전송 유실이 많은 경우 신중히 선택되어져야 하며 보통의 경우에는 1초 정도가 타당하다. $T_2$ parameter는 trnasmission efficiency의 개선에 있어 약간의 효과를 미치나 그리 크지는 않다.

• 한국작물학회지
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• 제67권1호
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• pp.67-75
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• 2022

Roots play important roles in water and nutrient uptake and in response to various environmental stresses. Investigating diversification of cultivars through root phenotyping is important for crop improvement in adzuki beans. Therefore, we analyzed the morphological and architectural root traits of 22 adzuki bean cultivars using 2-dimensional (2D) root imaging. Plants were grown in plastic tubes [6 cm (diameter) × 40 cm (height)] in a greenhouse from July 25^th to August 28^th. When the plants reached the 2^nd or 3^rd trifoliate leaf stage, the roots were removed and washed with tap water to remove soil particles. Clean root samples were scanned, and the scanned images were analyzed using the WinRHIZO Pro software. The cultivars were analyzed based on six root phenotypes [total root length (TRL), surface area (SA), average diameter (AD), and number of tips (NT) were included as root morphological traits (RMT); and link average length (LAL) and link average diameter (LAD) were included as root architectural traits (RAT)]. According to the analysis of variance (ANOVA), a significant difference was observed between the cultivars for all root morphological traits. Distribution analysis demonstrated that all root traits except LAL followed a normally distributed curve. In the correlation test, the most important morphological trait, TRL, showed a strong positive correlation with SA (r = 0.97^***) and NT (r = 0.94^***). In comparison, between RMT and RAT, TRL showed a significantly negative correlation with LAL (r = -0.50^***); however, TRL did not show a correlation with LAD. Based on RMT and RAT, we identified the cultivars that ranked 5% from the top and bottom. In particular, the cultivar "IT 236657" showed the highest TRL, SA, and NT, while the cultivar "IT 236169" showed the lowest values for TRL, SA, and NT. In addition, the coefficient of variance for the six tested root traits ranged from (14.26-40%) which suggested statistical variability in root phenotypes among the 22 adzuki bean varieties. Thus, this study will help to select target root traits for the adzuki bean breeding program in the future, generating climate-resilient adzuki beans, especially for drought stress, and may be useful for developing biotic and abiotic stress-tolerant cultivars based on better root trait attributes.

• 한국컴퓨터산업학회논문지
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• 제8권4호
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• pp.295-302
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• 2007

모바일 컴퓨팅은 무선이동체 통신과 휴대 정보 터미널, 인터넷을 이용하여, 컴퓨터와 인체의 정보 기술을 효과적으로 연계시켜, when, where, who, 이동하면서 사용이 가능한 현대 기술의 중추 적인 역할을 제공하며 새로운 기술을 생리학적 측정으로 재고하고, 창조적으로 재건 할 수 있다. 특히, 고령화 사회에서 병적 징후들이 질병으로 발전되기 이전에 생체 변화를 유도하는 과정에 개입할 수 있는 가능성을 제공해 줄 수가 있다. 그러나 많은 파라미터가 데이터처리, 데이터의 기준화의 모호함, 데이터의 동시수집이 어려움 등을 들 수 있다. 따라서 본 연구에서는 모바일 컴퓨팅을 활용하여 시간적 제한요소를 배제하고, 정확한 분석이 되는 접근으로 분석이 타당하고 생체전기 신호를 바탕으로 하는 모바일 신경역학적 코드화 방법을 채택하여 시스템을 구현하여 실험한 결과, 생체 신호 모바일 분석 장치의 모델이 될 수가 있었다.

• 농촌계획
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• 제21권1호
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• pp.117-127
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• 2015

This study evaluated properties and items for selecting on a forest healing village. In order to assign a weight value-between factors, this study was conducted the primary survey first and then the secondary survey for measuring the importance of items. Experts'surveys were conducted on 3 items on level 1, 9 items on level 2, 35 items on level 3 with use of AHP technique. In level 1, the main analysis result was that physical resource properties(0.387) indicated the highest importance. in level 2, healing resources of physical properties(0.402), community participation of human resource properties(0.425), and business competency in part of vision(-.438) showed the highest importance. The analysis result of 35 items on level 3 was that in physical resources properties, securing public land in the village(0.220), possessing recreation space(0.440) and resources available for link with healing(0.413) showed the highest importance. In part of human resources properties, the average age of residents(0.465), commitment to the promotion of the villagers(0.367) and support of local leaders(0.318) showed the highest importance. Adequacy of development plan(0.274), forest work experience-related(0.293), and building profit sharing system(0.282) were also evaluated to have a relatively high importance.