In this study, numerical analysis of TMD to estimate optimal-design-parameter is investigated using actual excitation, and evaluated by comparing results of numerical analysis and optimal-design-parameter was devised by Soong. It assumed between 1~2 seconds the 1st mode natural period of an aged apartment which has 10~15 stories and then investigated optimal-design-parameter of actual excitation for evaluate optimal frequency ratio and damping ratio according to local site condition. At this time mass ratio was 1% and range of tuned frequency ratio was 0.8Hz to 1.2Hz at intervals of 0.01Hz, and optimal damping ratio was 1% to 14% at intervals of 0.002%. It estimated Optimal-design-parameter was evaluated by numerical analysis according to peak and RMS displacement, acceleration respectively local site. And the result of evaluated respond performance parameter respectively a period was shown low numerical-value than optimal-design-parameter was devised by Soong what is more peak acceleration indicated performance difference of 20% over

In this study, the vibration control performance of Tuned Liquid Damper(TLD) with nonlinear properties is investigate by a with shaking table test according to large excitation. Until recently, TLDs has been investigated by behavior of liquid using equivalent TMD analogy and liner wave theory. The properties of TLDs assumed immutable but became generally known as a matter of fact TLDs behavior has a nonlinear properties that change the TLDs characteristics according to excitation. It was measured base shear and wave height in water tank at 0.01g to 0.06g as 0.01g intercals and tuned 0.6Hz, 0.8Hz. The result of shaking table test showed trend decreased amplification ratio of base shear and wave height as more increased peak accelearation of vibration, what is more jump frequency that dependent excitation dimension.

This paper presents a design process for viscoelastic dampers and a full-scale test of a 5-story steel structure with added viscoelastic dampers. The mechanical properties of viscoelastic dampers and the dynamic characteristics of the model structure were obtained from experiments, and the results were used in the design process. The additional damping ratios required to reduce the maximum response of the structure to a desired level were obtained first by the convex model. Then the size of dampers to realize the required damping ratio was determined using the modal strain energy method by observing the change in modal damping ratio due to the change in damper stiffness. The designed viscoelastic dampers were installed in the first and the second inter-stories of the model structure, and the system was excited by a hybrid mass driver located on the fifth floor. The experimental results indicated that after the dampers were installed the dynamic response of the full-scale model structure reduced as desired in the design process.

The apartment structures built using tunnel form method in 1980's, are vulnerable to lateral loads since wall elements don't exist in longitudinal direction and especially they were not seismically designed. In this study, in order to evaluate the seismic performance of those apartment structures, nonlinear analysis was performed and static test was conducted using small scale partial specimen. Both shear and moment should be considered for the structure subject to lateral load. Most existing methods, however, consider only shear force in test specimen because it is difficult to realize the actual moment distribution of the practical structure, and furthermore axial force is often neglected. This study propose a testing method which can realize similar moment and axial force distribution of a specimen to that of the practical structure by controlling the lateral loading condition. Numerical analysis was performed using moment-curvature curve considering stiffness degrading parameter, ductility-based strength and energy dissipation. The result of this study shows that only 15~20% difference exist between analysis and test, which confirms that the performance of wall elements in a non-seismically designed wall type reinforced concrete apartment can be accurately evaluated.

In this study, a seismic design methodology for a friction damper based on the story shear force of an elastic building structure is proposed. First, using two normalization methods for the slip-load of a friction damper, numerical analyses of various single-degree-of-freedom systems are performed. From those analyses, the effect of the slip-load and brace stiffness was investigated and the optimal stiffness ratio of the brace versus original structure was found. Second, from the numerical analysis for five multi-story building structures with different natural frequency and the number of story, reasonable decision method for the total number of installation floor, location of installation and distribution of slip-loads are drawn. In addition, an empirical equation on the optimal number of installation floor is proposed. Finally, the superiority of the proposed method compared to the existing design method is verified from the numerical analysis.

The purpose of this paper is to evaluate the performance of a MR fluid damper for seismic vibration control of a structure in terms of equivalent linear damping or stiffness based on linearization technique and to experimentally verify the results from linearization technique by comparing them to those from system identification of a building structure with MR damper. First, among the various models for MR damper, the equivalent stiffness and damping are estimated for Bingham model which is mathematically simple and for Bouc-Wen model which can describe any kind of hysteretic behavior. Second, transfer function of a building structure with MR damper is obtained by performing shaking table tests and the stiffness and damping matrices of the structure are constructed using the modal information obtained by the transfer function. It is observed that the damping mathematically estimated using linearization technique for Bingham model matches well with the damping coefficient experimentally obtained by system identification.

In this paper, the preliminary design procedure of magnetorheological (MR) dampers is developed for controlling the building response induced by seismic excitation. The dynamic characteristics and control effects of the modeling methods of MR dampers such as Bingham, biviscous, hysteretic biviscous, simple Bouc-Wen, Bouc-Wen with mass element, and phenomenological models are investigated. Of these models, hysteretic biviscous model which is simple and describes the hysteretic characteristics, is used for numerical studies. The capacity of MR damper is determined as a portion of not the building weight but the lateral restoring force. A method is proposed for optimal placement and number of MR dampers, and its effectiveness is verified by comparing it with the simplified sequential search algorithm. Numerical results indicate that the capacity, number and the placement can be reasonably determined using the proposed design procedure

In this paper, the stiffness and damping matrices are experimentally constructed using the structural modal information on frequencies, damping ratio and modal vectors, which are obtained by shaking table tests. Free vibration, harmonic and white noise vibration tests are performed. The acceleration of the shaking table was used as the input signal, and the resulting accelerations of each floor were measured as output signals. The characteristics and limitations of modal information from the each test are compared. The results of this study would be a basic resource of the analytical and experimental studies on the system identification of structures

In the capacity spectrum method (CSM), the peak response of an inelastic system under a given earthquake load is estimated transforming the system into the equivalent elastic one. This paper presented estimating the peak inelastic response is evaIuated by the CSM. The equivalent period and damping are calculated using the ATC-40, Gülkan, Kowalsky, and Iwan methods, and the performance points are obtained according the procedure B of ATC-40. Analysis results indicate that the ATC-40 method generaIly underestimates the peak response, while the Gülkan and Kowalsky methods overestimate the responses. The Iwan method produces the values between those by the ATC-40 method and the Gülkan and Kowalsky methods, and estimates the reponses relatively closer to the exact ones. Further, it is found that the Kowalsky method gives the negative equivalent damping ratios depending on the hardening ratios, and thereby can not be used to estimate the responses in some cases.

The purpose of this paper is to present a design method for friction damper (FD) for inelastic response control of short-period structure. A critical design parameter of FD is maximum friction force (MFF) and previous study evaluated MFF using equivalent damping ratio which is based on the maximum displacement. This procedure, however, gives the overestimated MFF for short-period structure. In this study, MFF of FD is evaluated based on RMS displacement response which is obtained by using given maximum response and peak factor. Numerical analysis shows that proposed method provide a reasonable MFF of FD for short-period structure.

The purpose of this study is to propose the general method for evaluating the equivalent damping ratios of a structure with supplemental response control dampers. We define Lyapunov function of which derivative can be expressed in autoregressive form and evaluate the equivalent damping ratios by using Lyapunov function and its derivative. This Lyapunov function may be called as generalized structural energy. In this study, it is assumed that the response of a structure is stationary random process and control dampers do not affect the modal shapes of a structure, and the structure has proportional damping. Proposed method can be used to get the equivalent damping ratios of a structure with non-linear control dampers such as friction dampers as well as linear control dampers. To show the effectiveness of the proposed method, we evaluate the equivalent damping ratios of a structure with viscous dampers, AMDs, and friction dampers. The equivalent damping ratios from proposed method are compared to those from eigenvalue analysis for linear control dampers, and those from time history analysis for non-linear control dampers, respectively.

The next generation small satellite-1 (NEXTSat-1) program has been kicked off in 2012, and it will be launched in 2016 for the science missions and the verification of space core technologies. The payloads for these science missions are the Instrument for the Study of Space Storms (ISSS) and NIR Imaging Spectrometer for Star formation history (NISS). The ISSS and the NISS have been developed by Korea Advanced Institute of Science and Technology (KAIST) and Korea Astronomy and Space science Institute (KASI) respectively. The ISSS detects plasma densities and particle fluxes of 10 MeV energy range near the Earth and the NISS uses spectrometer. In order to verify the spacecraft core technologies in the space, the total of 7 space core technologies (SCT) will be applied to the NEXTSat-1 for space verification and those are under development. Thus, the operation modes for the ISSS and the NISS for space science missions and 7 SCTs for technology missions are analyzed for the required operation time during the NEXTSat-1’s mission life time of 2 years. In this paper, the operational concept of the NEXTSat-1’s science missions as well as the verification of space core technologies are presented considering constraints of volume, mass, and power after launch.

This study was conducted to enhance the propagation of Acanthopanax divaricatus and Acanthopanax koreanum through different cutting practices. For propagation by cuttings, scions were taken on September 1. This already has hard skin and showed much higher values in terms of root length, root number, rooting ratio and root weight than those taken on June 30 and August 1. Regardless of cutting date, 50% shading resulted to the highest root length, root number, root ratio and root weight. Meanwhile, 95% shading significantly reduced these parameters compared with no shading. These results suggest that over-shading may inhibit root growth. Two growth regulators, IBA (concentration of 1,000, 2,000, 3,000 ppm) and Rootone-F (0.4%) were also tested of its effect to the cuttings. Rootone-F was found to be more effective than IBA. Cutting treated with Rootone-F had slightly higher root length and root number. A. koreanum which grows well in hot climatic condition showed better rooting ability than A. divaricatus.

The content of luteolin in the different parts of Lithospermum erythrorhizon was determined by high performance liquid chromatography (HPLC). Luteolin was quantified by a reverse-phase column with gradient solvent program (water : ACN = 90 : 10 to 77 : 23 for 60 min). UV detection was conducted at 330 nm. The content of luteolin was measured in the seeds (0.28 mg/g), stems (0.30 mg/g), and roots (0.16 mg/g) of L. erythrorhizon. The presence of luteolin in Lithospermum species is important in agricultural crop production for increasing the amounts of clinically available medicine and health supplements.

This study aims to understand the degree of inequality of surveyed amenity resources and identify which resource and region have the highest concentration by estimating Lorenz Curve and the Gini's Coefficient. The Lorenz Curve and Gini's Coefficient derived from economics are introduced as tools for investigating and quantifying regional variability of amenity resources concentration. This study describes the concepts underlying the application of the Gini's coefficient to measure the concentration of amenity resources in 11 regions, Chungbuk Province, Korea. The Lorenz Curve presents a graphical view of the cumulative distribution of amenity resources and the Gini's Coefficient provides a single-parameter measure of the distributional concentration of amenity resources. Also the Gini's Coefficient is compared to the number of amenity resource for understanding distributional difference between concentration and quantitative distribution of amenity resources. The results demonstrate significantly different regional variation according to the amenity variables: almost intact nature, interaction between nature and man, man-made.

Land cover and land use change data are important in many studies including climate change and hydrological studies. Although the various theories and models have been developed, it is difficult to identify the driving factors of the land use change because land use change is related to policy options and natural and socio-economic conditions. This study is to attempt to simulate the land cover change using the CLUE model based on a statistical analysis of land-use change. CLUE model has dynamic modeling tools from the competition among land use change in between driving force and land use, so that this model depends on statistical relations between land use change and driving factors. In this study, Yongin, Icheon and Anseong were selected for the study areas, and binary logistic regression and factor analysis were performed verifying with ROC curve. Land cover probability map was also prepared to compare with the land cover data and higher probability areas are well matched with the present land cover demonstrating CLUE model applicability.

Farmland spatial data are needed as a basic information in conducting rational use of farmlands in regional scale. This study develops a method that can be used to make up such farmland spatial data in a simple way and to develop a technique to manage them in a unitary way, and examines the effectiveness of the technique by applying it to the case area. A method that Web-Service Raster Image and Digital Cadastal Map can be utilized as a base map was devised. It was designed applying the vector system, in which one lot of farmland is area unit. Raster image and field survey data were combined to increase the accuracy of data. The lot boundaries of the existing boundary map were adjusted to the shapes of actual farmlands using GIS edition function. A proper farmland use classification system to the area characteristics was established and data obtained from the field survey were coded. Usually it is very difficult to identify the size of one lot of actual farmland in the existing space data, based on the results of the case study, the result map showed actual topography very realistically. Also the frequently occurring lot divisions and the serious topographical modifications by natural disasters frequently have made it impossible to survey farmlands on the catastral map in the field. But the final map had a great usefulness in that it may solve such problems by expressing the filed survey results graphically.

The aim of this paper is to investigate the applicability of high spatial resolution remote sensing images for conducting the rural amenity resources survey. There are a large number of rural amenity resources and field reconnaissance without a sufficient preliminary survey involves a big amount of cost and time even if the data quality cannot always be satisfied with the advanced study. Therefore, a new approach should be considered like the state-of-the-art remote sensing technology to support field survey of rural amenity resources as well as to identify the spatial attributes including the geographical location, pathway, area, and shape. Generally high-resolution satellite or aerial photo images are too expensive to cover a large area and not free of meteorological conditions, but recently rapidly-advanced internet-based image services, such as Google Earth, Microsoft Bing maps, Bluebirds, Daum maps, and so on, are expected to overcome the handicaps. The review of the different services shows that Google Earth would be the most feasible alternative for the survey of rural amenity resources in that it provides powerful tools to build spatial features and the attributes and the data format is completely compatible with other GIS(Geographic information system) software. Hence, this study tried to apply the Google Earth service to interpret the amenity resources and proposed the reformed work process conjugating the internet-based high-resolution images like satellite and aerial photo data.

The chemical composition of essential oil from the perennial herbaceous plants (Houttuynia cordata, Filipendula glaberrima, Peucedanum japonicum, and Ainsliaea acerifolia) was determined by GC/MS spectrometric analysis with the aid of NBS, Wiley Library and RI indice searches. The major constituents identified were α-phellandrene (18.97%), γ-terpinene (12.32%), decanal (8.72%), 1-decanol (10.92%), decanoic acid (12.12%), and 2-undecanone (12.32%) from H. cordata, farnesol (2.83%), l-α-terpineol (2.72%), benzenmethanol (2.03%), (Z)-3-hexen-1-ol (4.32%), and T-muurolol (2.07%) from F. glaberrima, α-phellandrene (14.25%), endobornyl acetate (3.84%), heptanal (47.52%), octanal (2.65%), (E,E)-2,4-decadienal (2.75%), and octanoic acid (4.52%) from P. japonicum, and geyrene (9.74%), β-cubebene (11.15%), berkheyaradulen (22.32%), β-elemene (6.21%), (-)-A-selinene (4.85%), benzaldehyde (4.52%), and benzenacetaldehyde (3.40%) from A. acerifolia.

The aim of this study is to analyze the green-tourism centrality considering spatial interaction using Gravity Model and social network method. The degree centrality and prestige centrality were applied as green-tourism centrality index. The rural amenity resources and human resources were counted as attraction factors, and a distance among villages was used as friction factor in gravity model. The weights of rural tourism amenity resources were calculated using the analytic hierarchy process(AHP) method and applied to evaluate green-tourism potentiality. The distance was measured with the shortest path among villages using geographic information system(GIS) network analysis. The spatial interaction from gravity model were employed as link weights between nodal points; a pair villages. Using the spatial interaction, the degree-centrality and prestige-centrality indices were calculated by social network analysis and demonstrated possibility of developing integrated green-tourism region centered on high centrality villages.