• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.159-163
• /
• 2005

Marine accidents of 70.9% have been caused by small ships less than 100 tons in the past 5 years(1998${\sim}$2002). This is ascribable to the graying and lack in expertise on shipping of small ship operators, and merchant ships are hindered from coastal navigation due to the increase of coastal fishing boats and liners. Currently, ECDIS and GPS Plotters are widely used as navigation equipment providing route information to operators, but it can not give any function of automatic route creation and route explanation, so they are available only experienced operators. Especially, the present situation is that no study is made of the automatic route creation and route explanation using ENC for ECDIS, substitution system of paper chart. In this paper, Navigation Guiding System(NGS) is proposed to generate an optimal route where ENC and GPS data is fusioned including the wind speed and direction of anemometer. The proposed system was testified by a simulation, and its effectiveness was verified.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.436-439
• /
• 2005

As mobile computers and embedded systems are becoming popular recently, we need to study how to utilize the resources such as power, space, CPU clocks, and memory efficiently. In traditional embedded system development, we were interested in resource usage based on hardware but, as software is becoming more important, we need to study how to analyze the resource usage based on software. In this research, we propose a new method called 'Instruction Level Resource Usage Analysis Method' and implement it as a resource usage analysis tool called 'I-Debugger'. I-Debugger is constructed on three layers: debugging layer which controls the execution of software on instruction level, statistic layer which gathers real-time data and convert to useful information, and analysis layer which generate useful information to specific applications. We have applied the debugger to some simple problem and found that our method is useful in developing resource efficient embedded systems.

• Journal of KIISE:Computer Systems and Theory
• /
• v.29 no.10
• /
• pp.582-588
• /
• 2002

Scalable displays generate large and high resolution images and provide an immersive environment. Recently, scalable displays are built on the networked clusters of PCs, each of which has a fast graphics accelerator, memory, CPU, and storage. However, the distributed rendering on clusters is a network bound work because of limited network bandwidth. In this paper, we present a new algorithm for reducing the network bandwidth and implement it with a conventional distributed rendering system. This paper describes the algorithm called geometry tracking that avoids the redundant geometry transmission by indexing geometry data. The experimental results show that our algorithm reduces the network bandwidth up to 42%.

• The KIPS Transactions:PartD
• /
• v.14D no.5
• /
• pp.517-530
• /
• 2007

Recently web applications have growl rapidly and have become more and more complex. As web applications become more complex, there is a growing concern about their quality. But very little attentions are paid to web applications testing and there are scarce of the practical research efforts and tools. Thus, in this paper, we suggest the automated testing methods for web applications. For this, the methods generate an analysis model by analyzing the HTML codes and the source codes. Then test targets are identified and test cases are extracted from the analysis model. In addition, test drivers and test data are generated automatically, and then they are depleted on the web server to establish a testing environment. Through this process we can automate the testing processes for web applications, besides the automated methods makes our approach more effective than the existing research efforts.

• The KIPS Transactions:PartD
• /
• v.15D no.1
• /
• pp.15-22
• /
• 2008

In this paper, we propose an efficient algorithm using only one-time database scan. The proposed algorithm creates the bipartite graph which indicates relationship of large items and transactions including the large items. And then we can find large itemsets using the bipartite graph. The bipartite graph is generated when database is scanned to find large items. We can't easily find transactions which include large items in the large database. In the bipartite graph, large items and transactions are linked each other. So, we can trace the transactions which include large items through the link information. Therefore the bipartite graph is a indexed database which indicates inclusion relationship of large items and transactions. We can fast find large itemsets because proposed method conducts only one-time database scan and scans indexed the bipartite graph. Also, it don't generate candidate itemsets.

• KIPS Transactions on Software and Data Engineering
• /
• v.4 no.11
• /
• pp.521-528
• /
• 2015

Road-view object classification methods are mostly influenced by weather and illumination conditions, thus the most of the research activities are based on dataset in clean weathers. In this paper, we present a road-view object classification method based on color segmentation that works for all kinds of weathers. The proposed method first classifies the weather and illumination conditions and then applies the weather-specified color models to find the road traffic signs. Using 5 different features of the road-view images, we classify the weather and light conditions as sunny, cloudy, rainy, night, and backlight. Based on the classified weather and illuminations, our model selects the weather-specific color ranges to generate Gaussian Mixture Model for each colors, Green, Yellow, and Blue. The proposed method successfully detects the traffic signs regardless of the weather and illumination conditions.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.5
• /
• pp.359-368
• /
• 2013

Mashup is a web application that combines several different sources to create new services using Open APIs(Application Program Interfaces). Although the mashup has become very popular over the last few years, there are several challenging issues when combining a large number of APIs into the mashup, especially when composite APIs are manually integrated by mashup developers. This paper proposes a novel algorithm for automatic Open API composition. The proposed algorithm consists of constructing an operation connecting graph and searching composition candidates. We construct an operation connecting graph which is based on the semantic similarity between the inputs and the outputs of Open APIs. We generate directed acyclic graphs (DAGs) that can produce the output satisfying the desired goal. In order to produce the DAGs efficiently, we rapidly filter out APIs that are not useful for the composition. The algorithm is evaluated using a collection of REST and SOAP APIs extracted from ProgrammableWeb.com.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.8 no.1
• /
• pp.37-43
• /
• 1996

Breaking waves were generated in a 2-D flume. A piston-type wavemaker was operated in accordance with signals which consist of elementary harmonics with appropriate phase differences. These phase differences were estimated by using a linear wave theory so that wave crests were to be concentrated at the same position. The stroke of wavemaker was controlled to create plunging-type breaking waves. The signal with small amplitude could not generate breaking waves. In the case of moderate amplitudes, various breaking waves could be obtained. Most of breaking waves were spilling type. Only when the wavemaker was operated with appropriate amplitude, plunging-type breaking waves were generated. The parameters of breaking waves are the wave steepness and the frequency bandwidth. If the central frequency was low, breaking waves were not generated. Based on experimental data, we found that the wave height of breaking inception was H = 0.0113 gT$^2$. We also made computations by using a mixed Euler-Lagrangian scheme under the assumption of potential flow. The numerical results show good agreements with tank measurements.

• Korean Journal of Community Nutrition
• /
• v.18 no.1
• /
• pp.45-54
• /
• 2013

This study was conducted to investigate the physical activity pattern, activity coefficient, basal metabolic rate and energy expenditure of female university students. One-day activity diaries were collected from 95 female university students in Seoul. Body composition was measured by Inbody 720. Subjects spent 7 hr 8min on sleeping, 6 hr 31min on studying, 2 hr 50min on physiological activity, 2 hr 3min on leisure, 2 hr 2min on walking and jogging, 1 hr 58 min on commuting and 22min on house chores. The activity coefficient of these subjects was 1.58. The comparison of body composition of subjects according to PAL showed that body weight, body fat mass, arm circumference and arm muscle circumference of physically active group were significantly higher than those of the sedentary group. BMR calculated by Harris-Benedict (H-B) formula and DRI formula and BMR measured by Inbody 720 was 1375 kcal, 1306 kcal and 1209 kcal, respectively. Total energy expenditure (TEE) examined by one-day activity diaries and calculated by H-B formula and estimated energy requirement (EER) formula in DRI was 2102.1 kcal, 2184.4 kcal, and 2164.5 kcal, respectively. The Pearson correlation coefficient between TEE examined by one-day activity diaries and H-B TEE was 0.795 (p < 0.001) while that between TEE examined and DRI EER was 0.604 (p < 0.001). Overall data indicated that female university students seemed to be less active. Therefore it is recommended that universities develop good exercise programs for their students. Further studies are needed to generate more meaningful results with a larger sample size and using machine attached to the body, which are able to detect physical activity more accurately.

• Journal of Korean Society of Disaster and Security
• /
• v.11 no.1
• /
• pp.1-5
• /
• 2018

Power plant is the important infrastructure to generate electricity. This plant in normally located next to river and seashore in order to take cooling water through intake. However, the plant is stopped when marine organism blocks the intake, and it caused damages by social and commercial. Therefore, air bubble barrier has been used to block marine organism in order to operate the plant properly. The aim of this study was to test the rates of cut off of floating substance by air bubble barrier to develop the facility for the plant. The test was conducted by current velocity, pressure of air, specific gravity of the substance and the layer of the barrier, and the result showed the blocking rates by the condition. It will be used as basic data to develop the air bubble barrier and to operate power plant properly from the marine organism.