• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1416-1424
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• 1996

The problem of optimaizing multiframe targe detection (MFTD) performance si discussed. The MFTD problem is treated as a multiple hypothesis desision problem, and a ne optimality criterion for the MFTD problem is established. It is of Neyman-Pearson (NP) type which is extended to multiple hypothesis cases. An optimal solution with respect tot eh established criterion is derived, and also proposed is a suboptimal solution which reduces the compelexity accompanying the optimal one. The trade-off between the reduction of complexity and the amount of loss in the detection performance is also studied. The proposed algorithm is applied to an active sonar system and the performance is evaluated via Monte-Carlo simulations.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.9
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• pp.773-777
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• 2016

In this paper, a novel multi-object tracking method to track an unknown number of objects is proposed. To handle multiple object states and uncertain observations efficiently, a probability hypothesis density (PHD) filter is adopted and modified. The PHD filter is capable of reducing false positives, managing object appearances and disappearances, and estimating the multiple object trajectories in a unified framework. Although the PHD filter is robust in cluttered environments, it is vulnerable to false negatives. For this reason, we propose to exploit local observations in an RFS of the observation model. Each local observation is generated by using an online trained object detector. The main purpose of the local observation is to deal with false negatives in the PHD filtering procedure. The experimental results demonstrated that the proposed method robustly tracked multiple objects under practical situations.

• Phonetics and Speech Sciences
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• v.1 no.4
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• pp.47-59
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• 2009

The purpose of this paper is to propose an automatic evaluation technique for the prosodic aspect of an English sentence uttered by Korean speakers learning English. The underlying hypothesis is that the consistency of the manual prosody scoring is reflected in an imaginary space of prosody evaluation model constructed out of the three physical properties of the prosody considered in this paper, namely: the fundamental frequency (F0) contour, the intensity contour, and the segmental durations. The evaluation proceeds first by building a prosody evaluation model for the sentence. For the creation of the model, utterances from native speakers of English and Korean learners for the target sentence are manually scored by either native teachers of English or Korean phoneticians in terms of their prosody. Multiple native utterances from the manual scoring are selected as the "model" native utterances against which all the other Korean learners' utterances as well as the model utterances themselves can be semi-automatically evaluated by comparison in terms of the three prosodic aspects [7]. Each learner utterance, when compared to the multiple model native utterances, produces multiple coordinates in a three-dimensional space of prosody evaluation, each axis of which corresponds to the three prosodic aspects. The 3D coordinates from all the comparisons form a prosody evaluation model for the particular sentence and the associated manual scores can display regions of particular scores. The model can then be used as a predictive model against which other Korean utterances of the target sentence can be evaluated. The model from a Korean phonetician appears to support the hypothesis.

• Communications for Statistical Applications and Methods
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• v.11 no.3
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• pp.643-655
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• 2004

L$_1$-estimator in the linear regression model is widely recognized to have superior robustness in the presence of vertical outliers. While the L$_1$-estimation procedures and algorithms have been developed quite well, less progress has been made with the hypothesis test in the multiple L$_1$-regression. This article suggests computer-intensive resampling approaches, jackknife and bootstrap methods, to estimating the variance of L$_1$-estimator and the scale parameter that are required to compute the test statistics. Monte Carlo simulation studies are performed to measure the power of tests in small samples. The simulation results indicate that bootstrap estimation method is the most powerful one when it is employed to the likelihood ratio test.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.10
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• pp.5095-5111
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• 2016

The Probability Hypothesis Density (PHD) filter is a suboptimal approximation and tractable alternative to the multi-target Bayesian filter based on random finite sets. However, the PHD filter fails to track newborn targets when the target birth intensity is unknown prior to tracking. In this paper, a dual detection-guided newborn target intensity PHD algorithm is developed to solve the problem, where two schemes, namely, a newborn target intensity estimation scheme and improved measurement-driven scheme, are proposed. First, the newborn target intensity estimation scheme, consisting of the Dirichlet distribution with the negative exponent parameter and target velocity feature, is used to recursively estimate the target birth intensity. Then, an improved measurement-driven scheme is introduced to reduce the errors of the estimated number of targets and computational load. Simulation results demonstrate that the proposed algorithm can achieve good performance in terms of target states, target number and computational load when the newborn target intensity is not predefined in multi-target tracking systems.

• ETRI Journal
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• v.43 no.3
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• pp.511-523
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• 2021

The World Health Organization provides guidelines for managing the particulate matter (PM) level because a higher PM level represents a threat to human health. To manage the PM level, a procedure for measuring the PM value is first needed. We use a PM sensor that collects the PM level by laser-based light scattering (LLS) method because it is more cost effective than a beta attenuation monitor-based sensor or tapered element oscillating microbalance-based sensor. However, an LLS-based sensor has a higher probability of malfunctioning than the higher cost sensors. In this paper, we regard the overall malfunctioning, including strange value collection or missing collection data as anomalies, and we aim to detect anomalies for the maintenance of PM measuring sensors. We propose a novel architecture for solving the above aim that we call the hypothesis pruning generative adversarial network (HP-GAN). Through comparative experiments, we achieve AUROC and AUPRC values of 0.948 and 0.967, respectively, in the detection of anomalies in LLS-based PM measuring sensors. We conclude that our HP-GAN is a cutting-edge model for anomaly detection.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.523-530
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• 2020

The efficient market hypothesis explains the random walk hypothesis suggesting that stock prices are independent of each other, hence, it is impossible to earn abnormal profits. The positive effect of a well-functioning and highly efficient stock market on the performance of an economy motivated the Philippine Stock Exchange to pursue massive modernization initiatives. This research provides evidence of the existence of random walk in the Philippine stock market employing the Augmented Dickey-Fuller (1981) and Phillips-Perron (1988) unit root tests, the Lo-MacKinlay's (1988) conventional variance ratio test, and Chow-Denning's (1993) simple multiple variance ratio test. Results of the ADF and PP unit root tests confirm the necessary condition for a random walk. The Chow-Denning (1993) maximum /z/ statistic and the Wald test statistic as in Richardson and Smith (1991) for the joint hypotheses and the Lo and MacKinlay (1988) individual statistics variance ratio test generally accepted the null hypothesis of a random walk. That is, the unit root and variance ratio tests consistently indicate that the null hypothesis of random walk cannot be rejected. The existence of a random walk in weak-form efficiency can be attributed to market liquidity as a result of continuous development and modernization of the Philippine equity market.

• Culinary science and hospitality research
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• v.4
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• pp.167-187
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• 1998

The human resources play an important role in a hotel cooking department. The object of this study is to gain basic data for searching an effective human resources management method of cooking department in the hotel. To achieve this object, I proceeded like this. In the second chapter, I exerted myself to arrange the theoretical system on the content of the human resources management through an internal and external philological research. In the third chapter, I established conceptional research model to study factual research and three hypotheses. And I made all high-grade hotel cooking employee in Taegu and Kyung-Buk answer an questionnaire, so practiced interrelation analysis and dispersion analysis according to research hypothesis. The results are as follows. First, the result of hypothesis 1 was that three was rather a high interrelation between the human resources management factor of cooking department and its overall evaluation. Second, the result of hypothesis 2 was that three was a significant difference about the overall evaluation of cooking business management according to the position demographically. Third, the result of hypothesis 3 was that there was a significant difference according to the scholastic ability, position and the district of hotel in the demographical evaluation of human resources management factor. The limits of this study were that first, I defined the subject as the cook employee of high-grade hotel in Taegu and Kyung-Buk, second, I utilized partial variance among many variances affecting human resources management. Therefore after this study, these limits much be overcomed and multiple and scientific study must be accomplish. So human resources of cooking department in the hotel must improve more.

• Journal of Korean Academy of Nursing
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• v.15 no.1
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• pp.30-43
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• 1985

Liver cirrhosis is the common cause of death in Korea today. But, if liver cirrhosis Patients were treated in the early stage of the disease Process, they can have a chance to carry their daily lives with prescribed medical and nursing regimens. Each patient has different health beliefs that there is a different Sick Role Behavior in the process of treatment. In order to increase and control the desired patient's Sick Role Behavior, it is important for nurses to understand the health beliefs influencing Sick Role Behavior. The purpose of this study was to determine factors influencing Sick Role Behavior and provide objective and scientific data to health education, treatment and nursing care. The subjects for this study were 80 Liver Cirrhosis patients selected from in and out patients of the medical department of four University Hospitals in Seoul, Won Joo and Mok Po city. Data was collected from Sep. 18, to Oct. 15, 1984. The measurement tool was the questionaire that developed by the investigator from the literature review based on Health Belief Model. The data Collection was done by interview. Analysis of data was done by use Mean, S.D., ANOVA, Pearson Correlation Coefficient and Stepwise Multiple Regression. The result of study were as follows: 1. The significant influencing variables on the Liver Cirrhosis Patient's Sick Role Behavior in general characteristics were Sex, Marital Status, Educational levels, Family's income and Duration after diagnosis. 2. Between the Sick Role Behavior and Health Belief Model, a) The first hypothesis that the stronger degree of Health Motivation, the higher degree of Liver Cirrhosis Patient's Sick Hole Behavior was supported (r=0.7892, p=0.0000). b) The second hypothesis that the higher degree of perceived susceptibility, the higher degree of Liver Cirrhosis Patients' Sick Role Behavior was supported (r=0.6383, p=0.0000) c) The third hypothesis that the higher degree of perceived severity, the higher degree of Liver Cirrhosis Patients' Sick Role Behavior was supported (r=0.5869, p=0.0000). d) The fourth hypothesis that the higher degree of perceived benefit, the higher degree of Liver Cirrhosis patient's Sick Role Behavior was supported (r=0.7535, p=0.0000). e) The fifth hypothesis that the lower degree of perceived barrier, the higher degree of Liver Cirrhosis Patient's Sick Role Behavior was supported(r=-9.7709, p=0.0000) f) The sixth hypothesis that the higher degree of knowledge in Disease, the higher degree of Liver Cirrhosis patients'lck Role Behavior was supported (r=0.7538, p=0.0000), g) In the correlation among variables, it was found positive correlation except that perceived barrier was negatively correlated. In the Stepwise Multiple Regression and Independent Variables, the factor“Health Motivation”could account for Sick Role Behavior in 62.28% of the Sample (F=128. 786, p<0.01). When the factor“perceived barrier”is added to this, it account for 70.38% of Sick Role Behavior (F=93.479, p <0.01) and the factor“knowledge in disease”is also included, it account for 74.78% of Sick Role Behavior (F=75.131, p <0.01). Finally, when the factor“perceived susceptibility”is included, it account for 75.03% of Sick Role Behavior (F=56.329, p <0.01).

• Health Policy and Management
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• v.15 no.1
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• pp.78-96
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• 2005

The purpose of this empirical study is to investigate whether costs are 'sticky' -that is, whether costs increase more when revenues rises than they decrease when revenues falls by an equivalent amount by using the financial data fromf korean general hospital Financial data used in this study were obtained from the Database of Korean Health Industry Development Institute and analyzed using multiple regression model in dummy variables. The main results of this study are as follows: First, we found, for 69 Korean general hospitals for 3 years(2000~2002), that total hospital costs, hospital labor costs, hospital administrative costs were sticky, these costs provided strong support for the sticky costs hypothesis 1, but hospital material costs were shown to be proportional to sales revenues. Second, this results provided strong support for the hypotheses that the' degree of stickiness was lower in sales revenues declining that were preceded by revenue-declining periods (hypothesis 2-1), and that stickiness was less pronounced in a second successive year of revenue decline(hypothesis 2-2). Third, this results provided strong support for the hypothesis(hypothesis 3) that stickiness was greater hospitals that employ relatively more people to support their sales revenues(hypothesis 4) that stickiness was greater for hospital that used relatively more assets to support their sales revenues. After all, a managerial implication of this study was that sticky cost, for the general hospital, could be recognized and controlled.