• Journal of Korea Port Economic Association
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• v.25 no.2
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• pp.73-94
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• 2009

In this paper the benefit was forecasted for traffic safety facilities to be constructed along the inland waterway between Phnom Penh and Chong Kneas(Siem Reap) port in Cambodia. First of all, the number of cruise ships passengers and cargo volumes were predicted. Second, the traffic volume of the cruise ships and cargo ships were calculated according to the prediction. Last, the safety benefit of traffic safety facilities was forecasted with the traffic after surveying the waterway accidents. The other benefit was also presented by converting the effect of relieving the emotional burden of navigators into currency value. Accordingly the entire benefit was estimated to be $14,990, $20,950 and $28,540 for pessimistic, moderate and optimistic prospects, in 2011. And then the entire benefits are calculated as $28,320, $63,060 and $95,230 for each prospect in the final estimation year 2020.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.1-6
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• 2002

To provide an easy operation of drift prediction model in SAR(search and rescue) mission a GUI program running on Window environment has developed. Users can make choice of input data on the screen by just clicking the mouse and the prediction results of datum points and trajectories of vessels are drawn on the map. The program contains both Leeway Equation model and mathematical model. The FORTRAN language was used in programming and Lehay Winteracter 4.0 software was utilized for graphic presentation. The result of May, 2001 Busan field experiment was plotted with that of model prediction for demonstration purpose.

• Journal of Navigation and Port Research
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• v.26 no.5
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• pp.491-495
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• 2002

To provide an easy operation of drift prediction model in SAR(search and rescue) mission a GUI program running on Windows environment has developed. Users can make choice of input data on the screen by just clicking the mouse and the prediction results of datum points and trajectories of vessels are drawn on the electric chart. The program contains both Leeway Equation model and Mathematical model. The FORTRAN language was used in programming and Lehay Winteraction 4.0 software was utilized for graphic presentation. The result of May, 2001 Busan field experiment was plotted with that of model prediction for demonstration purpose.

• Journal of KIISE:Software and Applications
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• v.30 no.3_4
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• pp.316-325
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• 2003

A user preference prediction method using an exiting collaborative filtering technique has used the nearest-neighborhood method based on the user preference about items and has sought the user's similarity from the Pearson correlation coefficient. Therefore, it does not reflect any contents about items and also solve the problem of the sparsity. This study suggests the preference prediction system using the similarity weight granted Bayesian estimated value and the associative user clustering to complement problems of an exiting collaborative preference prediction method. This method suggested in this paper groups the user according to the Genre by using Association Rule Hypergraph Partitioning Algorithm and the new user is classified into one of these Genres by Naive Bayes classifier to slove the problem of sparsity in the collaborative filtering system. Besides, for get the similarity between users belonged to the classified genre and new users, this study allows the different estimated value to item which user vote through Naive Bayes learning. If the preference with estimated value is applied to the exiting Pearson correlation coefficient, it is able to promote the precision of the prediction by reducing the error of the prediction because of missing value. To estimate the performance of suggested method, the suggested method is compared with existing collaborative filtering techniques. As a result, the proposed method is efficient for improving the accuracy of prediction through solving problems of existing collaborative filtering techniques.

• Journal of Korean Society of Forest Science
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• v.80 no.1
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• pp.9-19
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• 1991

This paper discusses the applicability of two simulation models for a ten year planning period in order to predict changing forest conditions. Two simulation models therefore were developed and applied to 3,844 ha of a national forest in Kangwondo province, which is managed by Joongbu Forest District Headquaters. Growth functions of three species were derived and used to predict the residual timber volume over time. Two alternative cutting schedules caused 10-14% difference in the residual timber volume in the end of ten year planning period. This suggests the important of correct decision-makings of forest managers in forest management planning.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.12
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• pp.561-568
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• 2021

In recent years, autonomous driving technologies have become a high-value-added technology that attracts attention in the fields of science and industry. For smooth Self-driving, it is necessary to accurately detect an object and estimate its movement speed in real time. CNN-based deep learning algorithms and conventional dense optical flows have a large consumption time, making it difficult to detect objects and estimate its movement speed in real time. In this paper, using a single camera image, fast object detection was performed using the YOLOv5 algorithm, a deep learning algorithm, and fast estimation of the speed of the object was performed by using a local dense optical flow modified from the existing dense optical flow based on the detected object. Based on this algorithm, we present a system that can predict the collision time and probability, and through this system, we intend to contribute to prevent tram accidents.

• Composites Research
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• v.28 no.6
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• pp.383-388
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• 2015

Ionic Polymer-Metal Composite (IPMC) consisting of soft membrane plated by platinum electrode layers on both surfaces generates electric energy when subjected to various mechanical stimuli. The paper proposes a circuit model that describes the physical composition of IPMC to predict the voltage generation characteristic corresponding to bending motion. The parameter values in the model are identified to minimize the RMS error between the real and simulated outputs. Following the design of IPMC circuit model, the state observer of the model is designed by using pole placement technique which improves the model accuracy. State observer design technique is also applied to find the inverse model which estimates the input bending angles from the output voltage data. The results show that the inverse model estimates input bending angles fairly well enough for the further applications of IPMC not only as an energy harvester but also as a bending sensor.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.30 no.8
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• pp.54-59
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• 2001

바낙 공기 급기(UFAD, underfloor air distribution)는 사무실과 상업 건물의 공조를 위하여 바닥 하부 공간을 사용하는 혁신적인 기술이다. 북미에서는 UFAD가 기존 천장 공기 급기 방식에 비하여 많은 장점을 지니므로 그 수요가 날로 증가하고 있다. 잘 설계된 UFAD 시스템은 다음과 같은 장점을 지닌다. - 건물의 용도 변경에 따픈 유연성이 우수하므로 건물의 생애 주기 비용을 감소시킨다. - 개별 쾌적성 제어가 가능하므로 온열 쾌적성, 거주자의 만족도 그리고 생산성을 향상시킨다. - 거주자주변에 직접 선선한 공기를 공급하므로 환기 효율, 실내 공기질 그리고 건강 상태를 향상시킨다. - 이코노마이저 운전, 온도 성층화 그리고 낮은 정합 운전에 의하여 에너지 비용을 감소시킨다. - 설비 공간이 축소되고 표준 철골 구조에서는 콘크리트 구조체 변경이 가능하므로 새 건축 공법에서는 충고를 감소시킬 수 있다. 1995년까지만 해도 UFAD는 파격적인 설계 기법이라고 여겨졌지만, 이제 설계자와 건축업자들은 2004년까지 신축되는 사무용 건축품의 35%는 바닥을 높인 기법이 적용되며 이 중 반 정도가 UFAD를 채택할 것이라고 예측하고 있다. 2000년 2억불이라고 추정되던 바닥을 높이는 건축의 시장 규모가 2004년에는 최소 10억불이 되리라고 예측된다. UFAD는 기본 연구에 의한 정립된 표준화된 설계 기법과 지침이 아직 마련되지 않았음에도 불구하고 현재 설계, 시공되고 있다. 이라한 경향은 펄수적인 연구가 수행되어 관련 업계가 지식과 경험을 충분히 쌓기 전까지는 계속될 전망이다. 본고는 시스템 설계와 운영의 주요한 특징, 기존 방식과 비교하여 지니고 있는 잠재적인 장점, 한계와 기술 개발의 필요성, UFAD 기술 개발을 위하여 계속적으로 요구되는 연구 분야 등을 서술함으로써 현재 UFAD 기술에 대한 평가를 한다.

• Survey Research
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• v.8 no.1
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• pp.55-79
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• 2007

This article attempts to provide an overview of the exit polls for the 2006 local elections in Korea. The sampling method, sampling error, non-response rate, and prediction error of the exit polls are reviewed. Also, we explore the fact that the propensity to vote varies according to age and gender of voters. In terms of age and gender, the representativeness of the sample is investigated by comparing to the data released by the National Election Commission. Through this empirical research, we show that the exit poll samples are unbalanced in terms of age and this unbalance may be one of the causes of bias occurred in the prediction of the 2006 local election results. The design effects of the sample design implemented for the exit polls are also examined.

• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.139-145
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• 2006

This paper develops pedestrian fatality models capable of producing the probability of pedestrian fatality in collision between vehicles and pedestrians. Probabilistic neural network (PNN) and binary logistic regression (BLR) ave employed in modeling pedestrian fatality pedestrian age, vehicle type, and collision speed obtained from reconstructing collected accidents are used as independent variables in fatality models. One of the nice features of this study is that an iterative sampling technique is used to construct various training and test datasets for the purpose of better performance comparison Statistical comparison considering the variation of model Performances is conducted. The results show that the PNN-based fatality model outperforms the BLR-based model. The models developed in this study that allow us to predict the pedestrian fatality would be useful tools for supporting the derivation of various safety Policies and technologies to enhance Pedestrian safety.