• ETRI Journal
• /
• v.44 no.5
• /
• pp.769-779
• /
• 2022

Spectral clustering has become a typical and efficient clustering method used in a variety of applications. The critical step of spectral clustering is the similarity measurement, which largely determines the performance of the spectral clustering method. In this paper, we propose a novel spectral clustering algorithm based on the local similarity measure of shared neighbors. This similarity measurement exploits the local density information between data points based on the weight of the shared neighbors in a directed k-nearest neighbor graph with only one parameter k, that is, the number of nearest neighbors. Numerical experiments on synthetic and real-world datasets demonstrate that our proposed algorithm outperforms other existing spectral clustering algorithms in terms of the clustering performance measured via the normalized mutual information, clustering accuracy, and F-measure. As an example, the proposed method can provide an improvement of 15.82% in the clustering performance for the Soybean dataset.

• The Korean Journal of Applied Statistics
• /
• v.22 no.6
• /
• pp.1315-1329
• /
• 2009

The panel survey is need to have a more concern about a response due to a secession and non-response of a sample. And generally a population is not fixed and continuously changed. Thus, the rotation sample design can be used by the method replacing the panel research. This paper is the study of comparison to equal weight method, Duncan weight, Design weight method, weight share method in rotation sample design. More specifically, this paper compared variance estimators about the existing each method for the efficiency comparison, and to compare the precision using the relative efficiency gain by the Coefficient Variance(CV) after getting the design weight from the actual data.

• Journal of Korea Multimedia Society
• /
• v.7 no.10
• /
• pp.1436-1442
• /
• 2004

A shared-based tree established by the Core Based Tree multicast routing protocol (CBT), the Protocol Independent Multicast Sparse-Mode(PIM-SM), or the Core-Manager based Multicast Routing(CMMR) is rooted at a center node called core or Rendezvous Point(RP). The routes from the core (or RP) to the members of the multicast group are shortest paths. The costs of the trees constructed based on the core and the packet delays are dependent on the location of the core. The location of the core may affect the cost and performance of the shared-based tree. In this paper, we propose three methods for selecting the set of candidate cores. The three proposed methods, namely, k-minimum average cost, k-maximum degree, k-maximum weight are compared with a method which select the candidate cores randomly. Three performance measures, namely, tree cost, mean packet delay, and maximum packet delay are considered. Our simulation results show that the three proposed methods produce lower tree cost, significantly lower mean packet delay and maximum packet delay than the method which selects the candidate cores randomly.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.22 no.51
• /
• pp.109-116
• /
• 1999

Most of carrying works have been performed in almost all production process, conveyer objects, machine equipment and work method. Then, they are made by unfitted design which doesn't consider physical condition of workers. So, it causes them to bring about forceful motion. This study investigated the back power for what difference between lumbar bending angle and back power by selecting 21 male aged 22∼30 years old. Lumbar angle were shared each 30, 60, 90 degrees and measured. The results of this study was that as lumbar angle was increasing, back power was decreased and were very significant differences for angles respectively. Besides. sample correlation coefficients were calculated in order to analyze the relationship between back power, anthropometric dimensions and grip strength. Back power was correlated with weight, arm length, hand length, breadth of palm, breadth of lower arm, breadth of wrist and left-right grip strength.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.3
• /
• pp.367-373
• /
• 2022

As deep learning-based autonomous driving technology develops, artificial intelligence models for various purposes have been studied. Based on these studies, several models were used simultaneously to develop autonomous driving systems. It can occur by increasing hardware resource consumption. We propose a multi-tasks model using a shared backbone to solve this problem. This can solve the increase in the number of backbones for using AI models. As a result, in the proposed lightweight model, the model parameters could be reduced by more than 50% compared to the existing model, and the speed could be improved. In addition, each lane can be classified through lane detection using the instance segmentation method. However, further research is needed on the decrease in accuracy compared to the existing model.

• Nuclear Engineering and Technology
• /
• v.50 no.4
• /
• pp.589-598
• /
• 2018

To maintain safety and reliability of reactors, redundant sensors are usually used to measure critical variables and estimate their averaged time-dependency. Nonhealthy sensors can badly influence the estimation result of the process variable. Since online condition monitoring was introduced, the online cross-calibration method has been widely used to detect any anomaly of sensor readings among the redundant group. The cross-calibration method has four main averaging techniques: simple averaging, band averaging, weighted averaging, and parity space averaging (PSA). PSA is used to weigh redundant signals based on their error bounds and their band consistency. Using the consistency weighting factor (C), PSA assigns more weight to consistent signals that have shared bands, based on how many bands they share, and gives inconsistent signals of very low weight. In this article, three approaches are introduced for improving the PSA technique: the first is to add another consistency factor, so called trend consistency (TC), to include a consideration of the preserving of any characteristic edge that reflects the behavior of equipment/component measured by the process parameter; the second approach proposes replacing the error bound/accuracy based weighting factor ($W^a$) with a weighting factor based on the Euclidean distance ($W^d$), and the third approach proposes applying $W^d$, TC, and C, all together. Cold neutron source data sets of four redundant hydrogen pressure transmitters from a research reactor were used to perform the validation and verification. Results showed that the second and third modified approaches lead to reasonable improvement of the PSA technique. All approaches implemented in this study were similar in that they have the capability to (1) identify and isolate a drifted sensor that should undergo calibration, (2) identify a faulty sensor/s due to long and continuous missing data range, and (3) identify a healthy sensor.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.3
• /
• pp.1-7
• /
• 2021

In this paper, optimized media data retrieval and transmission based on the Hybrid CDN/P2P architecture and selective storage through user's prediction of requestability enable seamless data transfer to users and reduction of unnecessary traffic. We also propose a new media management method to minimize the possibility of transmission delay and packet loss so that media can be utilized in real time. To this end, we construct each media into logical segments, continuously compute weights for each segment, and determine whether to store segment data based on the calculated weights. We also designate scattered computing nodes on the network as local groups by distance and ensure that storage space is efficiently shared and utilized within those groups. Experiments conducted to verify the efficiency of the proposed technique have shown that the proposed method yields a relatively good performance evaluation compared to the existing methods, which can enable both initial latency reduction and seamless transmission.

• The Journal of Society for e-Business Studies
• /
• v.14 no.2
• /
• pp.95-116
• /
• 2009

Ontologies have provided supports in integrating heterogeneous and distributed information. More and more ontologies and tools have been developed in various domains. However, building ontologies requires much time and effort. Therefore, ontologies need to be shared and reused among users. Specifically, finding the desired ontology from an ontology repository will benefit users. In the past, most of the studies on retrieving and ranking ontologies have mainly focused on lexical level supports. In those cases, it is impossible to find an ontology that includes concepts that users want to use at the semantic level. Most ontology libraries and ontology search engines have not provided semantic matching capability. Retrieving an ontology that users want to use requires a new ontology selection and ranking mechanism based on semantic similarity matching. We propose an ontology selection and ranking model consisting of selection criteria and metrics which are enhanced in semantic matching capabilities. The model we propose presents two novel features different from the previous research models. First, it enhances the ontology selection and ranking method practically and effectively by enabling semantic matching of taxonomy or relational linkage between concepts. Second, it identifies what measures should be used to rank ontologies in the given context and what weight should be assigned to each selection measure.

• Journal of Aerospace System Engineering
• /
• v.13 no.5
• /
• pp.1-8
• /
• 2019

Recently, avionics has been migrating from a federated architecture to an integrated modular architecture based on a multi-core to reduce the number of systems, weight, power consumption, and platform redundancy. The volume of data which must bo provided to the pilot through the display device has increased, because an integrated single device performs multiple functions. For this reason, the volume of data processed by the graphic processor within a fixed operation period has increased. In this paper, we provide a multi-core-based rendering engine in to perform more graphics processing within a fixed operation period. We assume the proposed method uses a multi-core-based partitioning operating system using the AMP (Asymmetric Multi-Processing) architecture.

• 모자간호학회지
• /
• v.3 no.2
• /
• pp.172-186
• /
• 1993

The survey was performed on 201 cases of mothers who visited pediatric hospitals and public health clinics in Pusan and Kyeong-nam provinces from Dec. 10 to Dec. 30 of 1993. If this study, each infant weighed over 2500gm and between 2 months and 12 months old. The research was statistically analyzed according to the percentage, Pearson correlation, $x^2$-test. The result of this study were as follows ; 1. Feeding method related to the job of mother (p<0.01). 2. Feeding method related to the way of bringing up child(p<0.05). 3. Whether the mother and child shared the same room effected the feeding method (p<0.01). 4. The shape of nipple before breast feeding related to feeding method. 5. The reason for stopping breast feeding related to feeding method(p<0.01). 6. First breast feeding related to period of seperation after delivery(p<0.05). 7. Plan of breast feeding related to birth weight (p<0.05).