• Atmosphere
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• v.20 no.4
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• pp.399-414
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• 2010

Sand and dust storm in East Asia, so called Asian dust, is a seasonal meteorological phenomenon. Mostly in spring, dust particles blown into atmosphere in the arid area over northern China desert and Manchuria are transported to East Asia by prevailing flows. An Asian dust event occurred on 6-8 May 2007 is chosen to investigate how sensitive the Asian dust transport forecast to the initial condition uncertainties and to interpret the characteristics of sensitivity structures from the viewpoint of dynamics and predictability. To investigate the forecast sensitivities to the initial condition, adjoint sensitivities that calculate gradient of the forecast aspect (i.e., response function) with respect to the initial condition are used. The forecast aspects relevant to Asian dust transports are dry energy forecast error and lower tropospheric pressure forecast error. The results show that the sensitive regions for the dry energy forecast error and the lower tropospheric pressure forecast error are initially located in the vicinity of the trough and then propagate eastward as the surface low system moves eastward. The vertical structures of the adjoint sensitivities for the dry energy forecast error are upshear tilted structures, which are typical adjoint sensitivity structures for extratropical cyclones. Energy distribution of singular vectors also show very similar structures with the adjoint sensitivities for the dry energy forecast error. The adjoint sensitivities of the lower tropospheric pressure forecast error with respect to the relative vorticity show that the accurate forecast of the trough (or relative vorticity) location and intensity is essential to have better forecasts of the Asian dust event. Forecast error for the atmospheric circulation during the dust event is reduced 62.8% by extracting properly weighted adjoint sensitivity perturbations from the initial state. Linearity assumption holds generally well for this case. Dynamics of the Asian dust transport is closely associated with predictability of it, and the improvement in the overall forecast by the adjoint sensitivity perturbations implies that adjoint sensitivities would be beneficial in improving the forecast of Asian dust events.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.659-662
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• 2012

In this paper, the service system the urgent of the danger area or the managed object region is proposed whether the system is autonomously the police or situation where it informs through the police car and it can convey the contextual information or not. In case the nodes location is continuously confirmed from the gateway and it queues and the event is generated in the server of system whether it is the situation, or not the system to be proposed transmits the event triggered message and system transmitting the video message to the nearby which the event is generated node. As a result of the test, in case the event was generated in the server whether it was the situation, or not it confirmed to transmit the video message as the route where it is stored in the server.

• Atmosphere
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• v.31 no.4
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• pp.377-394
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• 2021

The recent largest forest fire in the Yeongdong region, Goseung/Okgae fires of 2019 occurred during YangGang wind event. The wind can be locally gusty and extremely dry, particularly in the complex terrain of Yeongdong. These winds can cause and/or rapidly spread wildfires, the threat of which is serious during the dry spring season. This study examines the spatial variability of the surface wind and its coupling with the upper atmospheric wind using the data during the IOP of the Gangwon Yeongdong Wind Experiments (G-WEX) conducted in 2020 and the data during YangGang wind event on 4~5 April 2019. In the case of IOPs, strong wind at the surface with a constant wind direction appears in the mountain area, and weak wind with large variability in wind direction appears from foothill to the coast in the vicinity of Gangneung region. However, in the 2019 event, strong wind at the surface with a constant wind direction appears in the entire region from the mountain to the coast, even with the stronger wind in the coast than in some part of the mountain area. The characteristics of the upper atmospheric wind related with the spatial distribution of surface wind show that during IOPs of G-WEX, a strong downdraft exists near the mountaintop in the level of about 1 to 4 km. However, in the 2019 event a strong downdraft is reinforced, when its location moves toward the coast and descends close to the ground. These downdrafts are generated by the breaking of mountain waves.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.3
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• pp.248-253
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• 2008

This paper presents a sensing system for smart home which can detect an location transition events such as entrance/exit of a member and identify the user in a group at the same time. The proposed system is compose of two sub-systems; a wireless sensor network system and a database server system. The wireless sensing system is designed as a star network where each of sensing modules with ultrasonic sensors and a Bluetooth RF module connect to a central receiver called Bluetooth access point. We propose a method to discriminate a user by measuring the height of the user. The differences in the height of users is a key feature for discrimination. At the same time, the each sensing module can recognize whether the user goes into or out a room by using two ultrasonic sensors. The server subsystem is a sort of data logging system which read the detected event from the access point and then write it into a database system. The database system could provide the location transition information to wide range of context-aware applications for smart home easily and conveniently. We evaluate the developed method with experiments for three subjects in a family with the installation of the developed system into a real house.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.4
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• pp.163-171
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• 2019

PURPOSE: This study examined the incidence, location, and characteristics of sports injuries according to the position in Korean female national field hockey athletes. METHODS: Eighteen female national field hockey athletes (two goal keepers, five forwards, six midfielders, and five defenders) who trained at the national training center between January 2018 and December 2018 were enrolled. The event, position, and location of injury were recorded per IOC's daily injury reports form. The incidence of sports injuries was examined with the 95% confidence interval (CI), and the difference in the incidence of injury according to the position was presented as the rate ratio (RR). Moreover, differences in the location of sports injury according to the position were examined using χ2 tests. RESULTS: A total of 92 sports injuries occurred among field hockey players, with an incidence of 6.47 cases per 1,000 hours of training (95% CI 4.98-7.96). In addition, 29.12 cases of injuries occurred per 1,000 exposures (95% CI 23.17-35.07), and the incidence of injury was highest among the defenders, followed by forwards, midfielders, and goal keepers. The most common location of sports injury was the lower extremity, followed in order by the trunk, upper extremity, head, and neck, and there were significant differences in the location of the sports injury according to the position (p=.046). In addition, lumbar spine/lower back, thigh, ankle, lower leg, knee, and foot/toe were common sites of sports injury among female field hockey players. CONCLUSION: These results provide a baseline for predicting sports injuries in athletes during games, and would provide useful information for developing performance enhancement and injury prevention programs.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.2
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• pp.93-100
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• 2020

PURPOSE: This study examined the incidence, location, and characteristics of sports injuries according to the position in Korean female elite handball athletes. METHODS: Thirty handball athletes, who trained at between January 2019 and December 2019 were enrolled. The event, position, and location of injury were recorded according to the IOC's Daily injury reports form. The incidence of sports injury was examined with the 95% confidence interval (CI), and the difference in the incidence of injury by position was presented as the rate ratio (RR). Moreover, differences in the location of the sports injury according to the position were examined using χ2 tests. RESULTS: A total of 148 sports injuries occurred in the handball players, with an incidence of 22.71 cases of injury per 1,000 exposures (95% CI 19.05 - 26.37) The incidence of injury was highest in the Competition group, followed by the Weights and Training groups. The most common location of sports injury was the lower extremity, followed by the upper extremity, trunk. No significant differences in the location of sports injuries were observed according to the position (p = .384). In addition, the knee, ankle, lumbar spine/lower back, shoulder/clavicle were common sites of sports injury among handball players. CONCLUSION: These results provide a baseline for predicting sports injuries occurring in athletes during games, and would provide useful information for developing performance enhancement as well as injury prevention programs.

• Journal of the Korea Society of Computer and Information
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• v.15 no.3
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• pp.121-128
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• 2010

Whenever and wherever, recognizing location of object such as human as well as things, ubiquitous Location-Based Service which provides useful service based on this are rising as an important service. In this paper, we implemented customized real time 1:1 e-CRM system that can communicate with user's mobile phone through using Location-Based Service of mobile phone. Among various scenarios that are applicable to designed system, development and test were conducted based on scenario that provides shopping information and discount information to customers through SMS as they approach to vicinity of large discount store and allow them to download discount coupons through Call Back. The suggested system will be applied to various service event and can be used as a customized real time marketing method according to user's personal activity area.

• Journal of the Society of Disaster Information
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• v.15 no.2
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• pp.282-291
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• 2019

Purpose: In recent, mobile technology, as an axis of the fourth industry paradigm, is evolving into our daily life, economic activities and disaster safety management. However, since the location information service is insufficient, it is difficult to response the emergency situation adequately in the golden time. The purpose of this study is to propose a method to fine precisely the location of people who are in need of an emergency in the event of accidents and disasters. Method: This study investigates and compares existing literature and safety apps for national index number NFC application development. In addition, the system structure and the design method through the element technology through analysis of necessary function of the demander were carried out. Results: The results of this study were developed as a design and system that can be implemented in both direction and function to inform the location for emergency situation or disaster reporting in mobile. Conclution: It is possible to provide the disaster safety location service which can be utilized by the citizens in case of crisis by unifying the address system and integrating the location information using NFC.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.63.3-64
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• 2015

In our previous work (Kim et al., 2015), we suggested a new classification scheme, which categorizes the SPEs into four groups based on association with flare or CME inferred from onset timings as well as proton acceleration patterns using multienergy observations. In this study, we have tried to find whether there are any typical characteristics of associated events and acceleration sites in each group using 42 SPEs from 1997 to 2012. We find: (i) if the proton acceleration starts from a lower energy, a SPE has a higher chance to be a strong event (>5000pfu) even if the associated flare and CME are not so strong. The only difference between the SPEs associated with flare and CME is the location of the acceleration site. For the former, the sites are very low (~1Rs) and close to the western limb, while the latter has a relatively higher and wider acceleration sites. (ii) When the proton acceleration starts from the higher energy, a SPE tends to be a relatively weak event (<1000pfu), in spite of its associated CME is relatively stronger than previous group. (iii) The SPEs categorized by the simultaneous proton acceleration in whole energy range within 10 minutes, tend to show the weakest proton flux in spite of strong related eruptions. Their acceleration heights are very close to the locations of type II radio bursts. Based on those results, we suggest that the different characteristics of the four groups are mainly due to the different mechanisms governing the acceleration pattern and interval, and different condition such as the acceleration location.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.3
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• pp.179-184
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• 2015

In this study, the flap fatigue test of a 48 m long wind turbine blade was performed for 1 million cycles to evaluate the characteristics of acoustic emission signals generated from fatigue damage of the wind blades. As the number of hits and total energy continued to increase during the first 0.6 million cycles, blade damage was constant. The rise-time result showed that the major aspects of damage were initiation and propagation of matrix cracks. In addition, the signal analysis of each channel showed that the most seriously damaged sections were the joint between the skin and spar, 20 m from the connection, and the spot of actual damage was observable by visual inspection. It turned out that the event source location was related to the change in each channel's total energy. It is expected that these findings will be useful for the optimal design of wind turbine blades.