• Journal of Satellite, Information and Communications
• /
• v.8 no.4
• /
• pp.81-88
• /
• 2013

The satellite 2.1 GHz frequency bands, 1980-2010 MHz and 2170-2200MHz are allocated for mobile satellite service including satellite IMT, while it does not preclude the use of these bands for mobile services. The concept of an integrated satellite/terrestrial network has been introduced in worldwide because the terrestrial use in these bands adjacent to existing terrestrial IMT bands is attractive to provide mobile broadband services. The integrated satellite/terrestrial infrastructure with a high degree of spectrum utilization efficiency has the ability to provide both multimedia broadband services and public protection and disaster relief solutions. In addition, it is required to consider interference issues between the terrestrial and satellite components in order to reuse the same frequency band to both satellite and terrestrial component. This paper analyzes the interference for satellite downlink in the satellite/terrestrial integrated system and presents the interference mitigation techniques for satellite mobile earth station interfered by terrestrial base stations.

• The Journal of the Korea Contents Association
• /
• v.20 no.5
• /
• pp.609-622
• /
• 2020

With the development of society, the scale of the statute is not only increasing, but also the content is getting complicated. The scale of safety standards existing in the law is also increasing and specialized, making it difficult to integrate and manage to minimize conflicts or overlaps among safety standards. For the integrated management of safety standards, a technology that searches for and extracts safety standards in laws and regulations must first be secured. In this study, considering the limitations of time and manpower, a tool for automatic detection of safety standards is developed based on several specific cases. The safety standards classified in the previous studies and the safety standards announced by the Ministry of Interior and Safety were analyzed, and also statute information which includes safety standards extracted by the National Disaster Management Institute in 2018 was collected. After the collected laws were refined and morphological analysis was performed, a safety standard thesaurus was constructed and indexed to develop a safety standard search tool. When automatic search tools are routinely applied to find safety standards in the future, it is expected that these tools will help to solve overlapping or conflicting problems of complex safety standards.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.12
• /
• pp.5655-5662
• /
• 2011

This aim of the study intended to investigate the relationship among safety accident, impulsiveness and maternal child-rearing attitude of elementary students. The study was also done to acquire basic information on safety education program to help students be more aware of safety. A research was conducted from November 15 to 24, 2010 by means of self-report questionnaires distributed to 558 elementary students. Safety accident occurrence of subject is 51.3%, and the most frequent place was on school and home around. The safety accident occurrence was statistically significant difference according to students' gender, grade and the level of school life attitude. The safety accident occurrence correlated positively with authoritarian control, overprotection, and achievement, as defined maternal child-rearing attitude, and not with impulsiveness. The results of this study indicate that safety education program are needed to prevent the safety accidents, and to change the maternal child-rearing attitude of elementary students.

• Journal of the Korean association of regional geographers
• /
• v.17 no.3
• /
• pp.348-356
• /
• 2011

Someday Mt. Baekdu could erupt by records of orogeny activity until today. This study is to predict influence area of lava flow and volcanic ash by simulation of volcanic eruption in the Mt. Baekdu. Simulation for eruption applied to supposing 7 grade of volcanic explosivity index, season from fall to spring. As a simulation results, lava flewed down into slope of China and volcanic ash diffused over the North Korea. Volcanic ash spreads to Ulneung area after nine hours. It was predicted that 61 cities and villages out of 27 administrative districts of Si-Gun were affected by volcanic ash in North Korea and an immense volume of volcanic ash was blown into farm lands, city areas and forests. This results expected to utilize information for disaster preparation of North Korea and joint research with South-North Korea and China.

• Environmental Analysis Health and Toxicology
• /
• v.28
• /
• pp.10.1-10.4
• /
• 2013

Objectives Children are one of the most vulnerable populations to the impact of disasters. We aimed to examine children's mental health in the area affected by the Hebei Spirit oil spill accident on December 7, 2007. Methods A cross-sectional questionnaire survey was conducted using the Korean versions of the Children's Depression Inventory and State Anxiety Inventory for Children on 1,362 children attending elementary schools in the affected area. The information on distances between the nearest contaminated coastline to the child's residential house or attending school were obtained using a web-based map by inputting two address points. The symptom risks of depression and state anxiety were estimated by multiple logistic regression analyses adjusted for age, gender, and other covariates. Results Children with the closest distance (in the fourth quartile) to the school from the contaminated coastline showed a significantly higher symptom risk of depression compared to those with the farthest distance (first quartile)(odds ratio, 2.73; 95% confidence interval, 1.40-5.33), while there was no significant association between anxiety symptoms and distance. Conclusions Children, a vulnerable population for mental health impact by the oil spill accident, should be included in mental health programs in the community along with their family as victims of the disaster.

• Ocean and Polar Research
• /
• v.30 no.3
• /
• pp.277-287
• /
• 2008

We collected information on seasonal and interannual variability of surface chlorophyll a concentration between 1997-2007 from the Northwest Pacific Ocean. Satellite data were used to acquire chlorophyll a and sea surface temperature from six regions: East Sea/Ulleung Basin, East China Sea, Philippin Sea, Warm Pool region, Warm Pool North region, and Warm Pool East region. Mixed layer depth (MLD) was calculated from temperature profiles of ARGO floats data in four of the six regions during 2002-2007. In the East Sea/Ulleung Basin, seasonal variability of chlorophyll a concentration was attributed to seasonal change of MLD, while there was no significant relationship between chlorophyll a concentration and MLD in the Warm Pool region. Interannual anomaly in sea surface temperature were similar among the East Sea, East China Sea, Philippin Sea, and Warm Pool North region. The anomaly pattern was reversed in the Warm Pool East region. However, the anomaly pattern in the Warm Pool region was intermediate of the two patterns. In relation to chlorophyll a, there was a reversed interannual anomaly pattern between Warm Pool North and Warm Pool East, while the anomaly pattern in the Warm Pool region was similar to that of Warm Pool North except for the El $Ni\tilde{n}o$ years (1997/1998, 2002/2003, 2006/2007). However, there was no distinct relationship among other seas. Interestingly, in the Warm Pool and Warm Pool East regions, sea surface temperature showed a pronounced inverse pattern with chlorophyll a. This indicates a strong interrelationship among sea surface temperature-MLD-chlorophyll a in the regions. In the Warm Pool and Warm Pool East, zonal distribution of chlorophyll a concentration within the past 10 years has shown a good relationship with sea surface temperature which reflects ENSO variability.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.9
• /
• pp.841-849
• /
• 2008

Natural disaster such as inundation due to the typhoon induced storm-surge has inflicted severe losses on the coastal area. The problem of global warming and sea surface rising has issued and thus influences the increase of frequency and potential power of storm-surge. What we can do is to make intelligent effort to predict and prevent the losses through the early warning and prevention activity from the accurate prediction and forecasting about the time-varying storm-surge height and its arriving time resulted from the numerical simulation with sea observations. In this paper, we developed the web service based GIS-Enabled storm-surge visualization system to predict and prevent the storm-surge disasters. Moreover. for more accurate topography around coastal area and fine-grid storm-surge numerical model, we have accomplished GIS-based coastal mapping through LiDAR measurement.

• Journal of Multimedia Information System
• /
• v.1 no.2
• /
• pp.101-110
• /
• 2014

The purpose of this research is to extend Ad-hoc network system lifetime with the proposed routing protocol which has considered hop lifetimes of the nodes while guaranteeing QoS in the establishment process of Ad-hoc network communication paths. Based on another power aware routing system that proposed in the advanced research [1], we are proposing an alternative power aware routing system in which nodes' hop lifetimes are compared in order to extend the lifetime of an Ad-hoc network system and delay factors have been considered for the assurance of QoS. The research of the routing protocol in this paper, which aims to maximize the system survival time considering power consumption status during the path searching in MANET and pursues the mechanism that controls hop delays for the same reason, can be applied to the study of WSN. The study concerning such phenomena is essential so that the proposed protocol has been simulated and verified with NS-2 in Linux system focusing on the lifetimes of the hops of the nodes. Commercialization of smart devices and arrival of the ubiquitous age has brought about the world where all the people and things are connected with networks. Since the proposed power aware method and the hop delay control mechanism used to find the adequate communication paths in MANET which mainly uses batteries or in WSN, they can largely contribute to the lifetime extension of the network system by reducing power consumptions when utilized for the communications attempts among soldiers during military operation, disaster areas, temporary events or exhibitions, mobile phone shadow areas, home networks, in-between vehicle communications and sense networks, etc. This paper presents the definitions and some advantages regarding the proposed outing protocol that sustain and extend the lifetime of the networks.

• KCID journal
• /
• v.18 no.2
• /
• pp.87-100
• /
• 2011

This study is to delineate the watershed hydrological parameters such as area, slope, rain gauge weight, NRCS-CN and time of concentration (Tc) by using the Geographic Information Sytem (GIS) technique, and estimation of design flood for an ungauged watershed. Especially, we attempted to determine the Tc of ungauged watershed and develop simple program using the cell-based algorithm to calculates upstream or downstream flow time along a flow path for each cell. For a $19km^2$ watershed of tributary of Nakdong river (Seupmoon), the parameters including flow direction, flow accumulation, watershed boundary, stream network and Tc map were extracted from 30m Agreeburn DEM (Digital Elevation Model) and landcover map. And NRCS-CN was extracted from 30m landcover map and soil map. Design rainfall estimation for two rainfall gauge which are Sunsan and Jangcheon using FARD2006 that developed by National Institute for Disaster Prevention (NIDP). Using the parameters as input data of HEC-l model, the design flood was estimated by applying Clark unit hydrograph method. The results showed that the design flood of 50 year frequency of this study was $8m^3/sec$ less than that of the previous fundamental plan in 1994. The value difference came from the different application of watershed parameter, different rainfall distribution (Huff quartile vs. Mononobe) and critical durations. We could infer that the GIS-based parameter preparation is more reasonable than the previous hand-made extraction of watershed parameters.

• Journal of Advanced Navigation Technology
• /
• v.16 no.4
• /
• pp.697-702
• /
• 2012

With an elevator supply and demand increases, It has been enlarged various requirements for the safety of the elevator. Elevator safety requirements can be the ability to respond to emergencies quickly. Recently, QR code was attached to all elevator for the elevator safety and it is established by law for the Elevator rescue work. And also the elevator system is seeking to utilize more secure elevator with mandatory installation of CCTV and direct call devices. However, CCTV and direct call service is operating on an individual method and it has not been proposed integrated model. In this paper, we propose the safety elevator integration model with CCTV, direct call service and remote control based on smart phone. Using the proposed model, we can be improved the efficiency of maintenance and ability of prompt action in the event of a disaster.