• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.150-153
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• 1995

A Pinus densiflora forest in Chuwangsan was studied to determine the adequate plot area of shrub stratum for investigating forest community structure. Nineteen nested plots were set up in the studied forest, and species-area curve and performance curve were established. According to species-area curve, the minimum plot area where a given percentage increase in plot area produced less than the same percentage increase in number of species was 900$m^2$. The minimum plot area where a given percentage increase in plot area produced less than the half of the percent-age increase in number of species was 1,500$m^2$. According to performance curve of the importance values of the major species, the minimum plot area where the importance value of the major species was distinguished from each other was 1,400$m^2$. According to performance curve of species diversity, the minimum plot area was 750-1,500$m^2$. Similarity indices between plot area above 900$m^2$ and total plot area were more than 90% and similarity indices between plot area above 625$m^2$ and total plot area were more than 85%. It may be given as a conclusion that minimum plot area was about 1,500$m^2$ in case of requiring more accuracy.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.261-267
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• 2006

A nursery trial comprising 109 progenies of 5 populations of Cornus kousa was analysed using multivariate analysis of 12 quantitative traits (growth and leaf form). The aim of this study was to examine geographic variation of the species based on the single, existing nursery trial to support a genetic resource conservation plan of Cornus kousa in Korea. Nested Anova showed that there were statistically significant differences among populations as well as among families within populations in all 12 quantitative traits. In 10 of 12 traits, variance components among families within populations were higher than those among populations. Cluster analysis using complete linkage method showed three groups to Euclidean distance 0.8. Among principal components, primary 2 principal components appeared to be major variables because of the loading contribution of 91.9%. The first contribution component was maximum width, vein number, blade length/petiole length and upper 1/3 width lower 1/3 width; the second one was height, diameter at root collar, blade length, upper 1/3 width, petiole length and petiole length/vein number, respectively. But all characters showed no significant difference with the pattern of geographic distribution.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.187-191
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• 1994

A mixed forest community in Tokyusan was studied to determine the adequate plot area of tree stratum for investigating forest community structure. Nineteen nested plots were set up in the studied forest community, and species-area curve and performance curve were established. According to species-area curve, the minimum plot area where a given percentage increase in plot area produced less than the same percentage increase in number of species was 500$m^2$. The minimum plot area where a given percentage increase in plot area produced less than the half of the percentage increase in number of species was 1,000$m^2$. According to performance curve of the importance values of the major species, the minimum plot area where the importance value of the major species was distinguished from each other was 900$m^2$, and the minimum plot area was 500$m^2$ except for a big tree of Pinus densiflora distributed unexpectedly. According to performance curve of species diversity, the minimum plot area was 400$m^2$. Similarity indices between plot area above 900$m^2$ and total plot area were more than 90% and similarity indices between plot area above 400$m^2$ and total plot area were more than 85%. It may be as a conclusion that minimum plot area was generally about 500$m^2$ and in case of requiring more accuracy, minimum plot area was about 1,000$m^2$.

• Journal of the Korea Convergence Society
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• v.6 no.3
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• pp.103-109
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• 2015

TOLED(Transparent, Organic Light Emitting Diodes) based edutainment system has been studied to solve the actual feeling training and educational experience problem of e-learning. However, edutainment system using TOLED has a problem for the non-detection of multi marker array and rotate marker array, and it has problem for the dissonance phenomena caused by Illumination Environment between real world and virtual object. It also has a do not provide services through a variety of devices problem. Therefore, in this paper, we designed a system that provides a realistic actual feeling edutainment contents by recognizes the marker array rotation and a plurality of marker arrangement via an improved marker detection technique. And to unify the real space and virtual space of the lighting environment through a nested block layer.

• Proceedings of the Korea Database Society Conference
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• 1997.10a
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• pp.483-503
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• 1997

One important question that arises when dealing with temporal databases in context of object-oriented systems is the method that associates time with attributes relationship semantics. Results of previous work about attribute versioning, particularity extending flat(First Normal Form: FNF) or nested(Non-First Normal Form: NFNF) relational models. are not applicable to temporal object-oriented databases. This is because object-oriented models provide more powerful constructs than traditional models for structuring complex objects. Therefore, this paper presents an formal approach for incorporating temporal extension to object-oriented databases. Our goal in this paper is to study temporal object-oriented database representation according to generalization, aggregation and association among objects. We define tile concepts of attribute versioning in temporal object-oriented model, and we concentrate on the representation of temporal relationship among objects. Another contribution of this paper is to specify time constraints on relationship semantics and analyze our model based on representation criteria. By means of formalizing tile temporal object oriented model, this paper can not only provide tile robust operating functions that design algebraic operators, but also entrance the reuse of modules.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.2
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• pp.18-27
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• 2000

The importance of constraints has been one of major issues in recreation for prediction of choice behavior; however, traditional conjoint choice model did not consider the effects of these variables or fail to integrate them into choice model adequately. The purposes of this research are (a) to estimate the effects of constraints in theme park choice behavior by the constraints-induced conjoint choice model, and (b) to test additional explanatory power of the additional constraints in this suggested model against the more parsimonious traditional model. A leading polling agency was employed to select respondents. Both alternative generating and choice set generating fractional factorial design were conducted to meet the necessary and sufficient conditions for calibration of the constraints-induced conjoint choice model. Th alternative-specific model was calibrated. The log-likelihood ratio test revealed that suggested model was accepted in the favor of the traditional model, and the goodness-of-fit($\rho$$^2$) of suggested and traditional model was 0.48427 and 0.47950, respectively. There was no difference between traditional and suggested model in estimates of attribute levels of car and shuttle bus because alternatives were created to estimate the effects of constraints independently from mode related variables. Most parameters values of constraints had the expected sign and magnitude: the results reflected the characteristics of the theme parks, such as abundance of natural attractions and poor accessibility in Everland, location of major fun rides indoor in Lotte World, city park like characteristics of Dream Land, and traffic jams in Seoul. Instead of the multinomial logit model, the nested logit model is recommended for future researches because this model more reasonably reflects the real decision-making process in park choice. Development of new methodology too integrate this hierarchical decision-making into choice model is anticipated.

• Proceedings of the CALSEC Conference
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• 1999.07b
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• pp.587-596
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• 1999

In this paper, we introduce the design and development of a web-based workflow management system. The goal of the developed system is to manage business processes occurring in the CITIS (Contractor Integrated Technical Information Services) environment. The system is composed of three main modules: Process Designer, Workflow Engine, and Client modules. The Process Designer is a module that provides the environment for the build-time function, which generates the specifications of processes. The module presents the capability of defining nested process models, which is powerful in particular for designing complex processes. Since the other two modules are implemented using pure Java technology, the Workflow Engine can be implemented on any platform and the Client programs can be accessed via the WWW interface. This indicates that there is no need to install any client programs at the client-sides. Users who has a connection to the internet with web browsers, such as Internet Explorer and Netscape Navigator, and has a proper right of access can utilize the normal client, monitoring client, and system administration client programs. Communications between the workflow engine and the clients are implemented using the java servlet mechanism. The workflow system can serve as the underlying platform of process management tool in CALS and CITIS environments. An example scenario of using the system is presented.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.333-339
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• 2008

We investigated death rates, growth rates and recruitment of culms in two neighboring bamboo (Phyllostachys bamboosoides) stands nested in by two different bird species to analyze stand structure and to design conservation strategies. A third bamboo grove not used by birds, the Taewha stand, was included as a control stand. The bamboo stand occupied by birds in the family Ardeidae (the Ardeidae stand) had an approximately 1.5 times higher culm density than the stand occupied by birds in the family Corvidae (the Corvidae stand). The crude death rate and the number of newly emerged shoots were also higher in the Ardeidae stand than the Corvidae stand. The death rate for bamboo in the Ardeidae stand was not dependent on diameter at breast height (DBH) and was almost 40% for culms of all sizes, whereas most dead culms in the Corvidae stand were < 4 cm DBH. Consequently, we conclude that in the Ardeidae stand, density-independent causes of death are operating, while density-dependent factor are more important in the Corvidae site. The results of soil analysis in these stands suggest that the density-independent death pattern observed in the Ardeidae stand may be due to soil acidification resulting from wastes produced by the birds during breeding. On the other hand, the culm distribution and death patterns in the Corvidae stand suggest that the stand characteristics were not affected by the nesting birds. These results suggest that different conservation strategies must be applied to conserve bamboo groves used by ardeids and corvids for nesting.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.8 s.350
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• pp.15-24
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• 2006

We design and implement explicit mobile multicast, named XMIP, by enhancing explicit multicast for a great number of small group multicast communications. XMIP is a straightforward multicast mechanism without maintaining multicast states due to the inheritance from the explicit multicast based on a unicast routing. This research modifies and extends the functionality of each mobility agent of IETF Mobile IP for interworking XMIP XMIP Packets captured by an extended home agent are forwarded to each extended foreign agent through nested tunnels, named X-in-X tunnels, made by the binding table of the extended home agent. X-in-X tunneling mechanism can effectively solve the serious traffic concentration problems of Mobile IP multicast specifications. Finally heterogeneous mobile networks as an XMIP testbed including CDMA2000 1X EV-DO and WLAN are actually established, and a multi-user instant messenger system for small group communications is developed for verifying the feasibility of the proposed protocols.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.219-236
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• 2014

In this paper, we propose a novel Proxy Mobile IPv6 network bandwidth-efficient handoff scheme. MN are classified into slow and fast one. At first MN should be registered in the microcell for bandwidth efficient handoff scheme. microcell is overlapped to handle the overflow session request which is nested. Overflow session request in macrocell requests to go back from the boundary of the microcell to new microcell. If idle session traffic is in a cell, it is requested by the target microcell. Analysis model was developed, an existing session of the session blocking probability and forcing termination probability of the session request have improved considerably. If the total traffic load of the system is not very large, the proposed scheme has the best bandwidth efficiency and provides better quality of service (QoS) to MN without costs of a lot of processing on the system.