• Communications for Statistical Applications and Methods
• /
• v.11 no.2
• /
• pp.287-295
• /
• 2004

Mark Weiser introduced ubiquitous computing in his article titled 'The computer for 21st Century' in 1991. This has been new paradigm after internet. Now, the rapid development of mobile computer, wireless network, and intelligent system has supported ubiquitous computing environment. In the related area of information science, the researchers have studied on ubiquitous computing. But in the field of Korea statistics, this research has not been worked yet. So, we proposed the connection between statistics and ubiquitous computing in this paper. As an example, we showed an efficient cache hoarding for ubiquitous computing using statistical methods. In experimental results, we verified our proposed issue.

• ALGAE
• /
• v.20 no.1
• /
• pp.53-59
• /
• 2005

The objective of this study was to clarify marine algal flora and community structure of 16 uninhabited islands in Sinangun area, south western coast of Korea. As a result, a total of 63 species - 11 greens, 16 browns and 36 reds - was identified. The functional groups of marine algal species were filamentous 14.3%, foliose 20.5%, corticated 45.3%, leathery 13.7%, and articulated calcareous algae 6.2%. The (R+C)/P value was calculated as 2.9 showed temperate flora. The result of DCA showed that 16 uninhabitated islands tend to be distributed eastern and western parts. The dominant species was Ulva pertusa, while the subdominats were Gelidium divaricatum, Myelophycus simplex. The vertical distribution pattern of intertidal marine algae represented three distinct zones; Gloiopeltis furcata, Myelophycus simplex, Gelidium divaricatum - Ulva pertusa, Enteromorpha spp., Ishige okamurae - Ulva pertusa, Sargassum thunbergii, Symphyocladia latiuscula.

• Journal of the Korean Data and Information Science Society
• /
• v.15 no.3
• /
• pp.663-675
• /
• 2004

A battlefield simulation is the evaluation and analysis of the battlefield area, based on the data for terrain, climate, unit's maneuver and tactics basically required in battlefield simulation. Because it is difficult for the military authorities to collect all of the information perfectly for the reason of communication technology, jamming, and tactics, the military authorities need the future moving status for the target units by using acquired moving information. Therefore, we propose a moving object management system that concurrently provides domain reasoning function for the battlefield simulation. In order to implement the proposed system, we show the data modeling of the moving object for the battlefield simulation, and propose an inference engine using domain rule base and spatiotemporal operation. Also, we analyze the query response rate by inference function to verify domain reasoning of the implemented system.

• Proceedings of the KIEE Conference
• /
• 2001.04a
• /
• pp.329-331
• /
• 2001

This paper representes a realization of a fuzzy logic speed controller for BLDC motor drives. Fuzzy sets are regulated by using parameters of BLDC motor. Simplified reasoning methods are used for defuzzification. Fuzzy logic speed controller is designed by using the high performance of DSPchip (TMS320F240). By experiment, it is confirmed that the speed of BLDC motor well follows an command speed in the load variables or low-speed area.

• Journal of the Korean earth science society
• /
• v.23 no.3
• /
• pp.234-241
• /
• 2002

The purpose of the study is to investigate the applicability of portfolio assessment to ordinary elementary science classes, and the effects of a portrolio assessment on students' science achievement, inquiry ability, and science attiudes. Two schools were sampled from a metropolitan area, a city, and three schools from rural area in central Korea. Two fifth-grade classes were sampled from each school selected, and one class is assigned to experimental group and the other to control group, respectively. The total number of participants of the study are 475. Portfolio assessmest was administered to experimental group, and conventional teaching to control group for two and half month. Science achievement test, science inquiry ability test, and science attitudes test were administered as a pre- and post-test. Portfolio asseddment seems to be applecable to ordinary elementary science classroom. Statistically meaningful difference was not found in students' science achievemant by group, region, and sex. Students' inquiry ability and science attitudes showed statistically meaningful difference by region rather than group. Experimental group showed more positive scores on some sub-domains of science attitudes, such as perception on science education, and science career, interests in science activity, and criticism. In conclusion, portfolio assessment can be applicable to ordinary dldmentary science classrooms. The effects of portfolio assessment are at least the same as the traditional teaching on student science achievement, inquiry ability, and science attitudes.

• Journal of Korean Society for Atmospheric Environment
• /
• v.12 no.1
• /
• pp.15-21
• /
• 1996

Daily measutements of visibility on 09 LST have been made at a rural site in Chong-won, Chong-book since 1991 to find out a possible influence of emissions of anthropogenic pollutants and water vapout in urban and rural environments. Daily visibility data collected over four-year period were compared with the available visibility and air quality data obtainde from other stations. Detailed examinations of our data showed that the frequency of fog occurrence (visibility .leq. 1 km) at a rural site (KNUE) was at least three times higher (77 days per year) than the frequency of fog both in Chong-ju city (19 days) and at the Air Force Base(AFB) in the rural area. We interpret that the higher frequency of fog at KNUE was due to abundant water vapour in the Mieho River (upstream of the Keum River) area. In Chong-ju city, fog usually continued for a relatively long duration, while it dissipated simewhat faster in the rural environment due to higher solar radiation in the countryside area. The number of misty (.leg. 6 km) days (including foggy days) at KNUE were 235 days as compared with 135 days at the AFB and 67 days in Chong-ju city. In turn the number of days with low visibility (less than 6 km) at KNUE was about 64% per year. Since the moisture alone in a calm morning does not produce a visibility impairment, there must had abundant condensation nuclei including anthropogenic air pollutants. Air pollution was examined, for instance, average values of TSP for November and December 1993 were 115 and 116.mu.g/m$^{3}$, respectively. We conclude that the above mentioned environmental conditions with moisture are favourable for the formation of fog and mist in the rural sampling site at KNUE. Additionally, we found at least 10 days of acid fog at KNUE in September 1994 alone. Measured pH values in the acid for water were in the range of 4.36 .sim. 5.01 with the mean value of 4.51 Our observations suggested that strikingly acid fog do occur occasionally even in the rural environment.

• Journal of the Korean Geographical Society
• /
• v.32 no.2
• /
• pp.141-153
• /
• 1997

In Korea, cable television(CATV) broadcasting has begun in March, 1995. This Paper aims at examining the location of CATV broadcasting station, and demand density(numbers of viewer houshold) of broadcasting area, and at clarifing the factors affecting subscription. The results are as follows: The number of CATV stations is 54 in 1996, and these CATV stations are mainly located in larger cities. The correlation between the number of established or planned CATV station and the number of household is very high. In sphered broadcasting area Permitted in 1997, the location of CATV station is about 73,000 household and 230,000 persons in the minimum values of household and population, and diameter of sphered broadcasting area is 40.6 km in mean. The factors affecting subscription rates of CATV are median age and supply rates of apartment of each dong in Chongju city and each myun in Chongwon county. The correlation between subscription rates of CATV and supply rates of apartment appears higher than correlation between subscription rates and median age other factors based on residual analysis of regression equation are established period of transmission network of CATV and acceptance attitude of dwellers.

• Journal of Korean Society for Atmospheric Environment
• /
• v.21 no.3
• /
• pp.329-341
• /
• 2005

The purpose of this study is to study the $PM_{2.5}$ source characteristics affecting the Seoul area using a chemical mass balance (CMB) receptor model. This study was also to evaluate the $PM_{2.5}$ source profiles, which were directly measured and developed. Asian Dust Storm usually occurred in the spring, and very high $PM_{2.5}$ concentrations were observed in the fall among the sampling periods. So the ambient data collected in the spring and fall were evaluated. The CMB model results as well as the $PM_{2.5}$ source profiles were validated using the diagnostic categories, such as: source contribution estimate, t-statistic, R-square, Chi-square, and percent of total mass explained. In the spring months, the magnitude of $PM_{2.5}$ mass contributors was in the following order: Chinese aerosol $(31.7\%)>$ secondary aerosols ($22.3\%$: ammonium sulfate $13.4\%$ and ammonium nitrate $8.9\%)>$ vehicles ($16.1\%$: gasoline vehicle $1.4\%$ and diesel vehicles $14.7\%)>$biomass burning $(15.5\%)>$ geological material $(10.5\%)$. In the fall months, the general trend of the $PM_{2.5}$ mass contributors was the following: biomass burning $(31.1\%)>$ vehicles ($26.9\%$: gasoline vehicle $5.1\%$ and diesel vehicles $21.8\%)>$ secondary aerosols ($23.0\%$: ammonium sulfate $9.1\%$ and ammonium nitrate $13.9\%)>$ Chinese aerosol $(10.7\%)$. The results show that the $PM_{2.5}$ mass in the Seoul area was mainly affected by the Chinese area.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.7 no.6
• /
• pp.54-60
• /
• 2004

The purpose of this study is to analyzes the effects on planting of roof with planting block and grass in a school building where users actually spend daily life to measure indoor and outdoor temperature changes with existing roof. In case of planting of roof with a summer season, the highest temperature was shown lower about $1620^{\circ}C$ in the outdoor compared to the case of not performing it. On the other hand the lowest temperature was shown higher about $0.7^{\circ}C$ and the highest temperature lower about $1.1^{\circ}C$ in the indoor. In case of planting of roof with a winter season, the lowest temperature was shown higher about $1.712.8^{\circ}C$ compared to the case of not performing it. On the other hand, it was shown higher about $3^{\circ}C$ in the indoor. The results of this study, effects of temperature control was confirmed in the indoor where planting of roof was performed higher about $3^{\circ}C$ for winter season and lower about $1^{\circ}C$ for summer season compared to the case of indoor with existing roof.

• Journal of the Korean Institute of Telematics and Electronics T
• /
• v.35T no.2
• /
• pp.28-34
• /
• 1998

In this paper, I'd like to make a suggestion for boundary line detect algorithm which is used 3-D image processing system in order to track moving object. Through this study, more than anything else, difference image method was adopted to detect moving object in input image. To detect moving object, I made use of detect windows constructed by 4's predictive areas and object area for the purpose of reducing processing time and its size was determined by the size of moving object and prediction parameter directed center position. And also, tracking camera was movable toward the direction of X, Y by DC motor. As a conclusion of the study proposed algorithm, I found out the following results that tracking error was less than 6% of total moving object size and maximum tracking time 2 seconds by toy-car simulation.