• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.106-114
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• 2015

Despite a series of various developments in underwater acoustic sensor networks, there are still occasions of loss of connection over the network. Because sufficient amounts of drawbacks causing disconnections posed particularly in the middle of connection over the network emerge in the ocean environment, there is a need of new testing mechanism for underwater acoustic networks. In this paper, we proposed to investigate the most vital parts of the network deployment whether they function well in order, without any failure so as to identify where exactly communication process problems and failures are. We introduce step-wised out-test mechanism for UWASNS and accomplished the mechanism by implementing experiments and rigorously checked all the underwater devices utilizing out-test function. Experimental results and out-test function are evinced by implementing, in order to explain our system and conclude with possible future improvements.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.77-86
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• 2002

The purposes of this research which was conducted by surveying lost/added unit hours reports, unit hour demand analysis worksheets from prehospital care reports of two squads in Kyonggi Provincial Fire and Disaster Headquarters for 20 weeks (January 1, 2002 - May 20, 2002) are to get Unit Hour Utilizations. Call Demands such as Unit Hour Demand, Simple Average Demand, High Average Demand, Peak Average Demand, the High Actual Demand. The conclusions from this analysis were summarized as follows: (1) By revealing Unit Hour Produced 3223.9, Call Volume 964, Unit Hour Utilization 0.299 at the Squad A and Unit Hour Produced 3328.4, Call Volume 901, Unit Hour Utilization 0.271 at the Squad B induced Korean Squads to chance identification, definition, direction of Unit Hour Utilization. (2) By revealing Simple Average Demand 7.4 on Monday Tuesday, High Average Demand 9.6 on Tuesday Friday. Peak Average Demand 11.5 on Tuesday, the High Actual Demand 12 on Tuesday Wednesday at the Squad A and Simple Average Demand 6.8 on Sunday, High Average Demand 10.4 on Monday, Peak Average Demand 11.5 on Monday, the High Actual Demand 13 on Monday at the Squad B enabled Korean Squads to utilize System Status Management. (3) The Maximum Calls per Unit Hour were 115 for 23:00~23:59, the Minimum Calls per Unit Hour were 46 for 05:00~05:49 in two squads. The Maximum Calls per Unit Hour were 7.4 on Tuesday Saturday, the Minimum Calls per Unit Hour were 6.1 on Thursday at the Squad A. The Maximum Calls per Unit Hour were 7.3 on Monday Saturday, the Minimum Calls per Unit Hour were 5.6 on Thursday at the Squad B. (4) Analyzing demand for EMTs in the optimum emergency medical service of Korea, we have been able to utilize this Unit Hour Utilization in company with the established estimation methods such as international comparisons or the number of ambulances for scientific reasonable estimation. (5) These Call Demands which were limited to the demand time in this study will make us expect some following studies including demand time, demand time, demand map for Strategic Deployment.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.19-26
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• 2020

This paper analyses the feasibility of using implantable antennas to detect and monitor tumors. We analyze this setting according to the wireless propagation loss and signal fading produced by human bodies and their environment in an indoor scenario. The study is based on the ITU-R propagation recommendations and prediction models for the planning of indoor radio communication systems and radio local area networks in the frequency range of 300 MHz to 100 GHz. We conduct primary estimations on 915 MHz and 2.4 GHz operating frequencies. The path loss presented in most short-range wireless implant devices does not take into account the human body as a channel itself, which causes additional losses to wireless designs. In this paper, we examine the propagation through the human body, including losses taken from bones, muscles, fat, and clothes, which results in a more accurate characterization and estimation of the channel. The results obtained from our simulation indicates a variation of the return loss of the spiral antenna when a tumor is located near the implant. This knowledge can be applied in medical detection, and monitoring of early tumors, by analyzing the electromagnetic field behavior of the implant. The tumor was modeled under CST Microwave Studio, using Wisconsin Diagnosis Breast Cancer Dataset. Features like the radius, texture, perimeter, area, and smoothness of the tumor are included along with their label data to determine whether the external shape has malignant or benign physiognomies. An explanation of the feasibility of the system deployment and technical recommendations to avoid interference is also described.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.140-152
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• 2016

It is very important for the competitiveness and sustainable management of enterprises that the rapid changes in the managerial environments quickly and accurately are responded. For example, the large-scale investment accompanied by bad alternatives in accordance with misunderstanding of the managerial environments yields the huge cost and effort to modify and improve. In firm management, the quality of products and the productivity are influenced by changes of the endogenous factors yielded in manufacturing process and the exogenous factors as market, etc. These changes include not only changes in 4M (man, machine, material, method) but also those in the market, competitors, and technologies in the process of commodification, i.e., first, such disturbances make dispersion of the process big and odd. By Shewhart chart it can be checked that the process monitored is control-in or out. Business administration executes activities for input stabilization by monitoring changes in 4Ms, comparing with the standards, and taking measures for any abnormality. Second, TRM (technology road map) is to prospect product deployment and technological trend by predicting technologies in the competitive environment as the market, and to suggest the future directions of business. So, TRM must be modified and improved according to DR (design review) stages and changes in mass-production like input material change. Therefore, a role of TRM in input stabilization for reducing cost and man-hour is important. This study purposed to suggest that the environment changes are classified into endogenous factors and exogenous factors in production process, and then, quality and productivity should be stabilized efficiently through connection between TRM and input stabilization, and to prove that it is more effective for the display industry to connect TRM with input stabilization rather than to use TRM separately.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.139-148
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• 2012

PURPOSES : The accuracy of travel time information is a key measure of effectiveness and reliability of advanced traveler information systems. This study aims at investigating drivers' perception on the acceptable level of information accuracy and their corresponding valuations. METHODS : A questionnaire survey was executed for collecting driver perception data to capture the expectation level of travel time information provided and their willingness to pay for the information. A Tobit model was adopted for exploring the relationship among the acceptable level, driver socioeconomic characteristics and travel attributes. Since drivers' willingness to pay for accurate travel time information can be different according to their travel lengths, a piecewise linear regression model was developed to capture the sensitivity of values of travel time information to travel length. RESULTS : The analysis results suggest that trip purpose and travel time are two dominant factors to determine drivers' acceptable level of travel time information. For business and short trips, drivers want more accurate information than for non-business and long trips. Drivers' willingness to pay for travel time information also varies depending on their incomes, trip purposes and travel lengths. The results also show that drivers' valuation of travel time information provided is sensitive to their travel length. For longer trips, drivers are less sensitive to travel time information and then put less value on the information provided. CONCLUSIONS : Censored nonlinear regression models are developed to estimate drivers' acceptable accuracy for travel time information and their valuation using questionnaire survey data. The findings on drivers perception to the required accuracy of travel time information and their corresponding willingness to pay can be used in the design and deployment of advanced traveler information system to improve its effectiveness and usefulness through high compliance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.1
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• pp.47-52
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• 2008

The visual implementation of 3-dimensional national environment is focused by the requirement and importance in the fields such as, urban planing, telecommunication facility deployment plan, railway construction, construction engineering, spatial city development, safety and disaster prevention engineering. The currently used DEM system based on the 2-D digital maps and contour lines has limitation in implementation in reproducing the 3-D spatial city. Currently, the LiDAR data which combines the laser and GPS skill has been introduced to obtain high resolution accuracy in the altitude measurement in the advanced country. In this paper, we first introduce the LiDAR based researches in advanced foreign countries, then we propose the data generation scheme and an solution algorithm for the optimal management of our 3-D spatial u-City construction. For this purpose, LiDAR based height data transformed to DEM, and the realtime unification of the vector via digital image mapping and raster via exactness evaluation is transformed to make it possible to trace the model of generated 3-dimensional model with long distance for 3D u-city model generation.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.1
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• pp.105-115
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• 2008

The organization for satellite operation team is mainly based on the number of satellites to be controlled, operator's workload of payload operation support and the degree of automation of the operation system. Although the structure and its functionality of satellite operation organization are a little different according to the complexity of the operation, most satellite control centers have adapted the similar architecture for single or multiple satellite support. KARI Satellite Operation Center(KSOC) has started its simple mission operations since the launch of KOMPSAT-1(21st Dec. 1999) and has been evolving into multiple mission operations for various satellites such as KOMPSAT-2, KOMPSAT-3, KOMPSAT-5 and COMS(Communication Ocean Meteorological Satellite). This paper presents the appropriate direction of future deployment for KSOC by comparing the current status with the recommendation of the advanced satellite operation organization and analyzing their experiences in order to propose the better solution for efficient and safe satellite operations.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.617-625
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• 2013

Along with and <1Q84> Murakami Haruki sees through human nature that fades away with time in his latest work with 'color and memory'. This is the type of character or story to read with the deployment of instrument. Costume of characters conceived in the expansion of the body, the inner expression of personal notes. To others what you want to look, how they formed on the body, with a range of social, if you are claiming a statement. To form the body by forming self-practice is that there becomes. This paper the inside of the characters and the apparent strong interest in the set, costume characters, especially characters were recognized as representing the device of novel. Work directly in the results, or is described as a symbolic system of the body and clothing that embodies the meaning of the symbol you want to the structure of the exchange.

• Journal of Advanced Navigation Technology
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• v.23 no.6
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• pp.589-596
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• 2019

With the proliferation of intelligent transportation system (ITS) with dedicated short-range communication (DSRC) deployment, there are various applications requiring different throughput and reliability performance. To meet the enhanced throughput requirements in newly generated applications, IEEE 802.11bd is proposed to standardize for support of enhanced throughput and latency, preserving the fairness with previously deployed WLAN V2X devices. One of the main features of IEEE 802.11 bd is 20 MHz transmission to support the high data rate. In this paper, the primary channel selection method is proposed to guarantee the fairness with frame transmissions with 10 MHz bandwith including communications in WLAN V2X devices deployed with IEEE 802.11p. Simulation shows that the proposed channel access method for 20 MHz transmission with primary selection preserves the fairness without the change of channel access method in wide-band transmission.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.1
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• pp.51-61
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• 2011

A smartphone is a mobile phone that offers more advanced computing ability and connectivity than a contemporary basic feature phone. Unlike feature phone, a smartphone allows the user to install and run more advanced applications based on a specific platform. Smartphones run complete operating system software providing a platform for application developers. A smartphone will become the default computing method for many point activities in the not-too-distant future, such as e-mail, online shopping, gaming, and even video entertainment. For smartphone that contains sensitive information and access the Internet, security is a major issue. In the 1980s, security issues were hardly noticed; however, security is a major issue for users today, which includes smart phones. Because security is much more difficult to address once deployment and implementation are underway, it should be considered from the beginning. Recently our government recognized the importance of smartphone security and published several safety tips for using the smartphone. However, theses tips are user-oriented measures. Maintaining the security of a smartphone involves the active participation of the user. Although it is a important users understand and take full advantage of the facilities afforded by smarphone, it is more important developers distribute the secure smartphone application through the market. In this paper we describe some scenarios in which user is invaded his/her privacy by smartphone stolen, lost, misplaced or infected with virus. Then we suggest the security considerations for securing smartphone applications in respect with developers. We also suggest the methods applying domestic encryption algorithms such as SEED, HIGHT and ARIA in developing secure applications. This suggested security considerations may be used by developers as well as users (especially organizations) interested in enhancing security to related security incidents for current and future use of smartphones.