• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2135-2140
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• 2015

In this paper, proposed a new lighting control system which can reduce power consumption compared to conventional street lamps and intelligently control the light efficiently depending on whether there is a vehicle on the street. The new lighting control system proposed by this paper detects the presence of cars by collecting and analyzing sounds generated by the movement of cars. Then, the system controls lighting of street lamps based on the above car detection information, and turns on the street lamps sequentially by transmitting the car detection information. Experimental results showed that lightings were controlled based on the presence of cars and that operations of the lamps were made by turning on the lights sequentially by determining the moving direction of cars. This system is considered a technology that can reduce energies by applying to local roads with a few cars moving or national highways where lights are always turned on with low energy efficiency.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.6
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• pp.615-631
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• 2012

This study provides an evaluation for capability of Integrated Climate and Air quality Modeling System (ICAMS) on future regional scale climate projection. Temperature and precipitation are compared between ground-level observation data and results of regional models (MM5) for the past 30 years over the Korean peninsula. The ICAMS successfully simulates the local-scale spatial/seasonal variation of the temperature and precipitation. The probability distribution of simulated daily mean and minimum temperature agree well with the observed patterns and trends, although mean temperature shows a little cold bias about $1^{\circ}C$ compared to observations. It seems that a systematic cold bias is mostly due to an underestimation of maximum temperature. In the case of precipitation, the rainfall in winter and light rainfall are remarkably simulated well, but summer precipitation is underestimated in the heavy rainfall phenomena of exceeding 20 mm/day. The ICAMS shows a tendency to overestimate the number of washout days about 7%. Those results of this study indicate that the performance of ICAMS is reasonable regarding to air quality predication over the Korean peninsula.

• Proceedings of the KSRS Conference
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• v.1
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• pp.500-503
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• 2006

To adjust the discrepancy between Light Detection and Ranging (LIDAR) strips, previous researches generally have been conducted using conjugate features, which are called feature-based approaches. However, irrespective of the type of features used, the adjustment process relies upon the existence of suitable conjugate features within the overlapping area and the ability of employed methods to detect and extract the features. These limitations make the process complex and sometimes limit the applicability of developed methodologies because of a lack of suitable features in overlapping areas. To address these drawbacks, this paper presents a methodology using area-based algorithms. This approach is based on the scheme that discrepancies make complex the local height variations of LIDAR data whithin overlapping area. This scheme can be helpful to determine an appropriate transformation for adjustment in the way that minimizes the geographical complexity. During the process, the contour tree (CT) was used to represent the geological characteristics of LIDAR points in overlapping area and the Iterative Closest Points (ICP) algorithm was applied to automatically determine parameters of transformation. After transformation, discrepancies were measured again and the results were evaluated statistically. This research provides a robust methodology without restrictions involved in methods that employ conjugate features. Our method also makes the overall adjustment process generally applicable and automated.

• Journal of Positioning, Navigation, and Timing
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• v.6 no.4
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• pp.159-166
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• 2017

The position of autonomous driving vehicle is basically acquired through the global positioning system (GPS). However, GPS signals cannot be received in tunnels. Due to this limitation, localization of autonomous driving vehicles can be made through sensors mounted on them. In particular, a 3D Light Detection and Ranging (LIDAR) system is used for longitudinal position error correction. Few feature points and structures that can be used for localization of vehicles are available in tunnels. Since lanes in the road are normally marked by solid line, it cannot be used to recognize a longitudinal position. In addition, only a small number of structures that are separated from the tunnel walls such as sign boards or jet fans are available. Thus, it is necessary to extract usable information from tunnels to recognize a longitudinal position. In this paper, fire hydrants and evacuation guide lights attached at both sides of tunnel walls were used to recognize a longitudinal position. These structures have highly distinctive reflectivity from the surrounding walls, which can be distinguished using LIDAR reflectivity data. Furthermore, reflectivity information of tunnel walls was fused with the road surface reflectivity map to generate a synthetic reflectivity map. When the synthetic reflectivity map was used, localization of vehicles was able through correlation matching with the local maps generated from the current LIDAR data. The experiments were conducted at an expressway including Maseong Tunnel (approximately 1.5 km long). The experiment results showed that the root mean square (RMS) position errors in lateral and longitudinal directions were 0.19 m and 0.35 m, respectively, exhibiting precise localization accuracy.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.8
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• pp.23-32
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• 2007

We propose a group-based security scheme for hierarchical wireless sensor networks. We model the network for secure routing with 3-tier sensor network comprised of three types of nodes: Base Station, Group Dominator and ordinary Sensor Nodes. Group-based deployment is performed using Gaussian (normal) distribution and show that more than 85% network connectivity can be achieved with the proposed model. The small groups with pre-shared secrets form the secure groups where group dominators form the backbone of the entire network. The scheme is devised for dealing with sensory data aggregated by groups of collocated sensors; i.e., local sensed data are collected by the dominating nodes and sent an aggregated packet to the base station via other group dominators. The scheme is shown to be light-weight, and it offers a stronger defense against node capture attacks. Analysis and simulation results are presented to defend our proposal. Analysis shows that robustness can significantly be improved by increasing the deployment density using both the dominating and/or ordinary sensor nodes.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.1-10
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• 2016

Despite it has been mentioned that the successful restoration in landscape level was achieved in the Young-il soil erosion control project, quantitative evaluation of restored plant communities (Alnus firma as introduced species and Pinus thunbergii as native species) was hardly founded. Light availability, litter and woody debris cover, and forest structure and composition were determined for 500 m² band-quadrat in three forest types. Abiotic factors of Q. serrata stands, as reference forest, and A. firma stands were similar but not for P. thunbergii stands. There were no significant difference on mean stem density (stems ha^-1, H = 3.6, p = 0.162), and the mean basal area of each stand had marginal significance (m² ha^-1, H = 5.7, p = 0.058) among stands as total basal area was higher with the order of A. firma (21.4 m² ha^-1), P. thunbergii (19.8 m² ha^-1) and Q. serrata (16.2 m² ha^-1). Restoration of vegetation structure was more effective in fast-growing and N-fixing A. firma, as introduced species plantation. However, result of MRPP, NMS ordination and ISPAN for herbaceous layer, not for tree and shrub species composition, indicated that restoration of ground vegetation was likely influenced highly from local environment. Propagule availability from landscape context such as connectedness to natural vegetation and management practices in restored isolated stands are available explanations for restoration effects and gaps between restored plantations and secondary oak forest.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.63-83
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• 2006

This study conducted the following experiment to examine anesthetic effects of 500 kHz ultrasound with lidocaine. Clinical experiment was conducted to compare local anesthetic effects by ultrasound frequencies and drugs with 40 normal adults and it divided subjects into experimental group (I) applying only ultrasound, ointment group (II) applying only lidocaine, phonophoresis group of 1 MHz (III), phonophoresis group of 500 kHz lidocaine (IV) for pain threshold and nerve conduct experiments. Mechanical threshold was measured with von Frey monofilament, thermal pain threshold with halogen lamp and digital thermometer, action potential in median nerve with diagnostic electromyography before and after treatment, and at 30 min., 60 min., 90 min., and 120 min. after treatment. Results of this study can be summarized as follows. Topical anesthesia experiment showed that pain threshold of phonophoresis groups was significantly increased, but there were little differences in ultrasound frequency and drugs among phonophoresis groups. Conduction anesthesia experiment showed that phonophoresis group of 500 kHz using lidocaine had significant difference in pain threshold and sensory nerve conduction compared to ointment group and ultrasound group, but there was no great difference from other phonophresis groups and light nerve block effect was found. It was considered that application of 500 kHz ultrasound using lidocaine will be more effective in deep anesthesia or nerve block than 1 MHz ultrasound. However, researches considering various frequencies, intensities and application hours in low frequency areas including kHz ultrasound are needed to increase deep permeation of drugs.

• 전자공학회논문지 IE
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• v.46 no.1
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• pp.7-15
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• 2009

In this paper, automatic structure boundary extraction is proposed using terrestrial LIDAR (Light Detection And Ranging) in 3-dimensional data. This paper describes an algorithm which does not use pictures and pre-processing. In this algorithm, an efficient decimation method is proposed, considering the size of object, the amount of LIDAR data, etc. From these decimated data, object points and non-object points are distinguished using distance information which is a major features of LIDAR. After that, large and small values are extracted using local variations, which can be candidate for boundary. Finally, a boundary line is drawn based on the boundary point candidates. In this way, the approximate boundary of the object is extracted.

• The Journal of Fisheries Business Administration
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• v.48 no.2
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• pp.33-51
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• 2017

The purpose of this study is to estimate conservation value of fisheries resource protected area by the double-bounded dichotomous choice contingent valuation method. The data in this analysis come from a survey of respondents of resident in fisheries resource protected area using a proportional stratified sampling from the population. The questionnaires covered all the 5 fisheries resource protected area and the sample size of every protected area was 120 questionnaires. The survey period was from August to October in 2016. Above all, the average willingness to pay amount(WTP) per person of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, Cheonsu bay is estimated \6,215, \13,215, \6,405, \9,785, and \10,390 respectively. And, the total value of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, and Cheonsu bay is evaluated \108.8 billion, \357 billion, \118 billion, 210.2 billion, \ 245.8 billion respectively. Moreover, the yearly value of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, and Cheonsu bay is evaluated \6 billion, \19.6 billion, \6.5 billion, 11.6 billion, \ 13.5 billion. In conclusion, fisheries resource protected area has the higher conservational value. Consequently, it is essential for now or future generation's use of fisheries resources. In light of the fisheries resource protected area's value and importance, this should be promoted to the public including the local community who utilizes fisheries resource protected area wisely. Also, this suggests that the policy for fishery resource's creation and management is needed in fisheries resource protected area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.4
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• pp.359-366
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• 2007

Purpose: In spite of various advantages of hyaluronic acid in wound healing, there are few research about wound healing process and period in oral and maxillofacial surgery. So, We evaluated the effects of local application of hyaluronic acid gel on wound healing of the oral mucosa using this animal model. Materials and methods: Young adult New Zealand White rabbits, weighting between 2.5 and 3.0kg, were used. Almost uniform round ulcers could be created on the gingival of the rabbits by chemical injury with acetic acid. In experimental group, hyaluronic acid gel was applied daily until the wounds healed and in control group, ulcer lesion was not any treatment. The lengths of ulcers were measured the longest and shortest axes of the ulcers and calculated the areas of ulcer. For histological examination, specimens were made, and observed under a light microscope. Results: The results showed that the number of fibroblasts, new blood vessels and the epithelial thickness from experimental group was higher than from control group. Hyaluronic acid promoted proliferation of the fibroblast, keratinocytes isolated from gingival tissue of rabbits in vitro. Topical application of hyaluronic acid accelerated healing of ulcers created in rabbits. Conclusion: The hyaluronic acid may be effective for wound healing of oral mucosal lesions.