• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.12
• /
• pp.2813-2819
• /
• 2015

In this paper, we investigate the physical layer network coding (PNC) technique in a two-way relay channel (TWRC) where two source nodes send and receive data with each other via a relay node. In particular, we consider the communication scenario where packet length from the two sources is different from each other. We analyze the bit error rate (BER) of the received packet at the relay node according to degree of overlapping between two packets. The BER of the short packet remains unchanged regardless of the degree of overlapping since the entire packet is overlapped with the longer packet, while the BER of the longer packet becomes improved as the degree of overlapping decreases. Thus, we need a novel transmission scheme to enhance BER performance of the PNC technique in TWRC environments since the overall BER performance of the PNC technique at the relay node depends on the worse BER between two ovelapping packets' BERs.

• School Mathematics
• /
• v.18 no.4
• /
• pp.749-771
• /
• 2016

The purpose of this study is to analyze mathematical tasks of Korea and the USA textbooks focused on conditions for parallelograms. In this study, structures of task, types of proof and reasoning, and levels of cognitive demand are investigated. The conclusion is as follows: First, with respect to structures of task, structures presented in the USA textbooks are more diverse. Second, with respect to types of proof and reasoning, Korea and the USA prefer IC task and DA task. And task types presented in the USA textbooks are more diverse. Third, with respect to levels of cognitive demand, in both Korea and the USA textbooks, PNC task and PWC task account most. And compared to the USA, Korea prefer algorithms. In addition, we find out implications for reconstruction of Korea textbook. It is as follows: First, with respect to structures of task and types of proof and reasoning, the diversity of composition needs to be raised. Second, with respect to levels of cognitive demand, the concentration in PNC task needs to be declined. And levels of cognitive demand on types of tasks need to be reconsidered. Third, with respect to tasks' topic and material, internal and external connectivities of mathematics need to be strengthened.

• The KIPS Transactions:PartC
• /
• v.19C no.4
• /
• pp.247-252
• /
• 2012

Network coding has been shown to improve various performance metrics in network systems. However, if network coding is implemented as software a huge time delay may be incurred at encoding/decoding stage so it is imperative for network coding to be parallelized to reduce time delay when encoding/decoding. In this paper, we compare the performance of parallelized decoders for random linear network coding (RLC) and pipeline network coding (PNC), a recent development in order to alleviate problems of RLC. We also compare multi-threaded algorithms on multi-core CPUs and massively parallelized algorithms on GPGPU for PNC/RLC.

• Journal of Nutrition and Health
• /
• v.13 no.2
• /
• pp.92-103
• /
• 1980

Components of neutral lipids and amino acids of Hirneola auricula-Judae and Gyrophora esculenta grown in Korea were compared by using a Thinchrography (latroscan TH-10) and an amino acid auto analyzer(Technicon PNC-1 type), respectively. Cholesterol ester and tripalmitin were the major components among the triglycerides in both of the samples. From the total amino acids which are closely related with the nutritional valuation, aspartic acid was in the richest amount and then came with glutamic acid, serine, alanine and valine in Hirneola auricula-Judae and Gyrophora esculents contained large quantity of glutamic acid.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.12
• /
• pp.2313-2321
• /
• 2008

In order to develop reliable on-site partial discharge(PD) pattern recognition algorithm, the fuzzy neural network based on fuzzy set(FNN) and the polynomial network pattern classifier based on fuzzy Inference(PNC) were investigated and designed. Using PD data measured from laboratory defect models, these algorithms were learned and tested. Considering on-site situation where it is not easy to obtain voltage phases in PRPDA(Phase Resolved Partial Discharge Analysis), the measured PD data were artificially changed with shifted voltage phases for the test of the proposed algorithms. As input vectors of the algorithms, PRPD data themselves were adopted instead of using statistical parameters such as skewness and kurtotis, to improve uncertainty of statistical parameters, even though the number of input vectors were considerably increased. Also, results of the proposed neuro-fuzzy algorithms were compared with that of conventional BP-NN(Back Propagation Neural Networks) algorithm using the same data. The FNN and PNC algorithms proposed in this study were appeared to have better performance than BP-NN algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.8A
• /
• pp.656-663
• /
• 2005

This paper presents a multi-channel enhancement scheme for the MAC protocol of IEEE 802.15.3 High-rate WPAN (Wireless Personal Area Network). The current MAC protocol of the IEEE 802.15.3 High-rate WPAN is designed for sharing a single channel among DEVs of a piconet; that is, within a single piconet, PNC prevents interference through MAC layer assignment of time slots to other DEVs using time-division multiple access. When the number of DEVs that communicate with each other frequently, is increased in a single WPAN, the size of the superframe becomes inevitably large, and this may result in a significant throughput drop or a failure to provide QoS guarantee. A multi-channel enhancement scheme for the MAC protocol of IEEE 802.15.3 High-rate WPAN is proposed to significantly increase the aguegate throughput and more reliably provide the QoS guarantees in a piconet

• Proceedings of the SAREK Conference
• /
• 2007.06a
• /
• pp.208-208
• /
• 2007

• Korean Journal of Veterinary Service
• /
• v.30 no.3
• /
• pp.393-406
• /
• 2007

Bovine tuberculosis is an important zoonosis worldwide. Mycobacterium bovis, the causative agent of this disease in cattle, is also a pathogen for humans and several economically important animals. The cases of tuberculosis are reported in two cow found at slaughter house located in Gwangju city. Histopathologically, in the lymph nodes, granulomas consisted of large areas of necrosis surrounded by variable thick bands of cellular infiltrate containing macrophages, Langhans-type multinucleated giant cells and lymphocytes. Lesions in the lung followed the same developmental pattern as did lesions in the lymph nodes with some exceptions. With the acid-fast staining, numerous mycobacteria were revealed in the lung and lymph nodes. M bovis was confirmed as a causative agent in these cattle using bacterial isolation and PCR and restriction fragment length polymorphism method based on a unique 12.7 kb fragment insertion sequence from the Mycobacterium tuberculosis genome and the pncA polymorphism, The insertion element IS6110 and IS1081 were present M bovis isolated from lungs and lymph nodes of cattle using PCR assay. These cases are interesting and important in public health aspect that M bovis-infected cattle were found during a routine post-mortem inspection at slaughter house.

• The Mathematical Education
• /
• v.60 no.1
• /
• pp.61-76
• /
• 2021

The purpose of this study is to analyze the errors and difficulties which pre-service secondary teachers shows during the task modification in consideration of the cognitive demand and to provide significant implications to the pre-service teacher education program related to the modification of the mathematical tasks. In the pursuit of this purpose, tasks were selected from perpendicular bisector units and 24 pre-service teachers were asked to modify the tasks to higher and lower level tasks. After the modification activities, opportunities for reflection and modification were provided. The findings from analysis are as follows. Pre-service teachers had a difficulty to distinguish between PNC tasks and PWC tasks. Also, We identified the interference phenomena that pre-service teachers depended on the apparent elements of the task. Pre-service teachers showed a tendency to overlook the learning objectives and learning hierarchy during the task modification, and to focus on some types of task modification. However, pre-service teachers were able to have meaningful learning opportunities and extend the category of tools to technology including Geogebra through self-reflection and correction activities on task modification. The above results were summed up and we presented the implications to the task modification program in the pre-service secondary teacher education.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.3A
• /
• pp.230-236
• /
• 2007

This paper presents a resource management mechanism for the mesh networking in IEEE 802.15.3 High-rate WPAN. IEEE 802.15 TGS is standardizing the MAC and PHY for mese networking. This task group researches the mechanism that are extension of network coverage without increasing transmit power of receive sensitivity, and studies the enhanced reliability via route redundancy. In this paper we propose the distributed resource management scheme that is fairly using the channel resource in the piconet without centralized piconet coordinator. Each DEV reserves the channel time and broadcasts its information. This scheme has unfairness for later associated DEV because of preoccupation of earlier associated DEVs. This paper presents the method that fairly allocates the channel time in MAC layer. And we evaluate the performance enhancement using simple simulations.