• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.83-91
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• 2008

Previous settlement prediction methods based on settlement monitoring were developed under instantaneous loading condition and have restriction to be applied to soft ground under ramp loading condition. In this study, settlement prediction method under ramp loading was developed. New settlement prediction method under ramp loading considered influence factors of consolidation settlement such as thickness of clayed layer, quantity of surcharge load and preconsolidation pressure, etc. Geometrical correction method based on hyperbolic method (1991) and correction method based on probability theory were applied to increase accuracy of settlement prediction using field monitoring data after ramp loading. Large consolidation tests for ideally controlled one dimensional consolidation under ramp loading condition were performed and the settlement behavior was predicted based on the monitoring data. New prediction method yielded good result of entire settlement behavior by using data during an early stage of ramp load. Additionally, new prediction method offered better settlement prediction which had final settlement prediction in close proximity and low RMSE(Root Mean Square Error) than previous method such as hyperbolic method did.

• Journal of the Korean housing association
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• v.17 no.4
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• pp.119-130
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• 2006

Apartment houses, the representative type of urban housing, are becoming an important element in Korea urban landscape. In this regard, this study aims to consider landscape in view of city residents reflecting human's visual perceptual characteristic, and in line with this, the urban landscape of apartment houses viewed from the urban center main intersections has been embodied according to the physical components of the intersections, which was followed by preference survey of the city residents, and then based on this, the visual-perceptual characteristics were examined. The findings are as follows: 1. The findings gained from the average of the landscape types indicate that the city residents are more satisfied when the shielding by surrounding buildings is minimized, view securing is relatively good, the whole complex is clearly observed because of its proximity to the visual point, and the view of the complex is well recognized from the focus point. 2. The examination concerning the preferred factors positively evaluated in terms of architectural planning shows that when the complex view is changeable sophisticated, makes the residents feel comfortable with its stable, open plan, and it's in harmony with surroundings, such housing attracts the city residents. 3. In terms of architectural planning factors, it turned out that the complex is more preferred when the visibility of the complex and the scale of surrounding green space are in good condition, and such elements of the complex as the sky line, the overall shape, the elevation, variation of the shape and height are harmonious with one another.

• Journal of Digital Convergence
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• v.16 no.9
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• pp.437-442
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• 2018

The study aims to identify key players through the last five passes when entering shooting circles in Korea and top four countries participated in the Rio Olympics. First, the analysis code was created using the Sports code to analyze the 29 games including Korea and the top 4 countries among 33 games. Second, Ucinet 6 has been used to analyze the Closeness Centrality of each country. The results of the study show that Korea is a key player in No.13 FW, New Zealand in No.1 MF, Germany in No.5 DF, Netherlands in No.9 MF and U.K in No.8 MF. In particular, the two teams that advanced to the finals saw their proximity center index average over 60. Based on these results, it is expected that the analysis of women's field hockey matches will serve as a tool to identify key players.

• International Journal of Highway Engineering
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• v.18 no.6
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• pp.69-76
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• 2016

OBJECTIVES : The objective of this study is to propose a capacity analysis methodology for riverside bike-exclusive roads. METHODS : Three steps were performed to develop a methodology to estimate bikeway capacity. First, we reviewed previous studies on the vehicle-road capacity analysis and proposed their applicability to bikeways. Second, two assumptions were made based on the traffic flow characteristics of bikeways: (1) the capacitated state in bikeways occur within a bicycle platoon, and (2) a bicycle platoon consists of more than three bicycles running in close proximity. In addition, it is assumed that the mean time headway of a bicycle platoon represents the characteristics of the platoon. The normality of the mean-time headway of a bicycle platoon calculated using the central limit theorem leads to the development of a method that estimates the riverside bikeway capacity using data collected from two different riverside bike-exclusive roads (Han-river and Anyangcheon). We used a location-fixed video camera to record videos of running bicycles and wrote a special-purpose software program to code the time-headway data from the videos. RESULTS : Time headways from 189 bicycle platoons were analyzed. The estimated mean-time headway of the capacitated bicycle flow is 1.01 s, from which the capacity of the bikeway is found to be 3578 vehicles/h. CONCLUSIONS : The proposed method that estimates bikeway capacity could be applicable to the analysis of short-range congested area rather than planning the number of lanes. In other words, it determines the sections that are temporarily highly congested and proposes appropriate strategies to mitigate the congestion.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.2
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• pp.243-252
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• 2018

In this paper, we propose a bone region extraction method using a snake algorithm and a particle filter in CT image. We extract the bone outline using the snake algorithm, and extract the bone area by moving the particle filter along this outline. If other bones are in close proximity to the bone outline, the snake algorithm may not be able to extract the bone outline completely. At this time, the particle filter extracts the bone area while compensating for the error. In this paper, we compared the proposed method with the conventional morphological processing method. The result is similar when other bones are not close to the bone area to be extracted. However, if other bones are close to each other, The accuracy of the proposed method is higher than the conventional morphological processing method.

• Journal of Korea Technology Innovation Society
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• v.21 no.1
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• pp.354-384
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• 2018

This paper aims at analyzing the effect of the relationship between innovation intermediaries and firms on firms' absorptive capacity from the perspectives of social capital. And it also analyzes how firms' innovation environment influences on their absorptive capacity in this process. For this purpose, we carry out an empirical analysis on 200 firms in the Daedeok Innopolis, which is the representative innovation cluster in Korea. According to this study, firm's absorptive capacity is positively affected by the reliability and frequency of firms' communication with innovation intermediaries. However, the geographic proximity does not have significant influence. Also, the innovation environmental factors play a positive moderating role in the absorptive capacity of firms, and the social factors have a distinct significant influence on it directly. Based on these findings, this paper would make a contribution to recognize the importance of innovation intermediaries in innovation process and their role as preceding factors to firms' absorptive capacity, as well as innovative environment in the innovation process.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.1
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• pp.101-110
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• 2004

The robots that will be needed in the near future are human-friendly robots that are able to coexist with humans and support humans effectively. To realize this, humans and robots need to be in close proximity to each other as much as possible. Moreover, it is necessary for their interactions to occur naturally. It is desirable for a robot to carry out human following, as one of the human-affinitive movements. The human-following robot requires several techniques: the recognition of the moving objects, the feature extraction and visual tracking, and the trajectory generation for following a human stably. In this research, a predictable intelligent space is used in order to achieve these goals. An intelligent space is a 3-D environment in which many sensors and intelligent devices are distributed. Mobile robots exist in this space as physical agents providing humans with services. A mobile robot is controlled to follow a walking human using distributed intelligent sensors as stably and precisely as possible. The moving objects is assumed to be a point-object and projected onto an image plane to form a geometrical constraint equation that provides position data of the object based on the kinematics of the intelligent space. Uncertainties in the position estimation caused by the point-object assumption are compensated using the Kalman filter. To generate the shortest time trajectory to follow the walking human, the linear and angular velocities are estimated and utilized. The computer simulation and experimental results of estimating and following of the walking human with the mobile robot are presented.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.4
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• pp.720-740
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• 2011

Wi-Fi-enabled portable devices have recently been introduced into the consumer electronics market. These devices download or upload content, from or to a host machine, such as a personal computer, a laptop, a home gateway, or a media server. This paper investigates the fairness among multiple Wi-Fi-enabled portable devices in a home network when they are simultaneously communicated with the host machine. First, we present that, a simple IEEE 802.11-based home network suffers from unfairness, and the fairness is exaggerated by the wireless link errors. This unfairness is due to the asymmetric response of the TCP to data-packet loss and to acknowledgment-packet loss, and the wireless link errors that occur in the proximity of any node; the errors affect other wireless devices through the interaction at the interface queue of the home gateway. We propose a QoS-provisioning framework in order to achieve per-device fairness and service differentiation. For this purpose, we introduce the medium access price, which denotes an aggregate value of network-wide traffic load, per-device link usage, and per-device link error rate. We implemented the proposed framework in the ns-2 simulator, and carried out a simulation study to evaluate its performance with respect to fairness, service differentiation, loss and delay. The simulation results indicate that the proposed method enforces the per-device fairness, regardless of the number of devices present and regardless of the level of wireless link errors; furthermore it achieves high link utilization with only a small amount of frame losses.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.185-195
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• 2020

Background: The flathead grey mullet Mugil cephalus has the widest distribution among mugilid species. Recent studies based on mitochondrial DNA sequences showed that the species comprises at least 14 different groups, three of which occur in the northwest Pacific. We analyzed the otolith microchemistry of M. cephalus at several locations in Korea to improve understanding of migration pattern and population origin. Results: We collected 123 sagittal otoliths from seven locations and determined their concentrations of eight elements (⁷Li, ²⁴Mg, ⁵⁵Mn, ⁵⁷Fe, ⁶⁰Ni, ⁶³Cu, ⁸⁸Sr, and ¹³⁸Ba) using laser ablation inductively coupled plasma mass spectrometry. Mean otolith elemental ratios differed significantly among the locations. The Sr:Ca, Fe:Ca, and Ba:Ca ratios were significantly higher than others, and useful chemical signatures for investigating the habitat use of M. cephalus populations. We identified five diverse and complicated migration patterns using the otolith data that we collected: estuarine resident (type I), freshwater migrant (type II), estuarine migrant (type III), seawater resident (type IV), and seawater migrant (type V). A canonical discriminant analysis plot revealed separation of two groups (type II in the Yellow Sea vs. other types in remaining locations). Two locations on Jeju Island, despite their close proximity, had fish with quite different migration patterns, corroborating previous molecular studies that distinguished two groups of fishes. Conclusion: We successfully showed that the migration patterns of the Korean mullet varied by location. Only fish from the western sector of Jeju had a unique migration pattern, which is likely confined population in this area. Among the eight otolith elements measured, the Sr:Ca ratio was found to be the best indicator of migration pattern and population origin.

• Journal of KIISE
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• v.44 no.4
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• pp.374-382
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• 2017

As the walking exercise is emphasized in personalized healthcare, numerous services demand walking information. Along with the propagation of smartphones nowadays, many step-counter applications have been released. But these applications are error-prone to abnormal movements such as simple shaking or vibrations; also, different step counts are shown when the phone is positioned in different locations of the body. In this paper, the proposed method accurately counts the steps regardless of the smartphone position by using an accelerometer and a proximity sensor. A threshold is set on each of the six positions to minimize the error of undetection and over-detection, and the cut-off section is set to eliminate any noise. The test results show that the six position type were successfully identified, and through a comparison experiment with the existing application, the proposed technique was verified as superior in terms of accuracy.