• Korean Journal of Occupational Health Nursing
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• v.9 no.2
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• pp.110-120
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• 2000

The purpose of this study was to examine which factors affected the job stress of workers in the manufacturing industry. The subjects were 128 workers in automobile component manufacturing companies located in Kyonggi-do province. Data were collected through self-reporting technique for 8 days, October 24-31, 2000. The instrument to test the work related truss was NIOSH's Work-related Stress Inventory revised by Korea Occupational Safety and Health Association(KOSHA) in 1999. The collected data were analysed with SAS. and frequency, percentage, mean value, standard deviation, t-test, ANOVA. Scheffe's post hoc test and Pearson's Correlation Coefficients. The major findings were as follows: 1. Mean job stress score for the job-related stress was $2.6{\pm}0.5$ on the basis of 5.0 points. Job stress was significantly different according to gender. The stress by role conflict showed higher score than the stress by role ambiguity. 2. Discretionary power(freedom to determine) of workers was scored $2.6{\pm}0.7$ on the basis of 5.0 points. And it was significantly different according to gender, duration of work and shift experience. 3. The work environment scored $2.2{\pm}0.3$ on the basis of 3.0 points and significant difference according to gender, age, marital status, type of employment, type of service, and shift work. 4. Role ambiguity showed significant negatively correlate with job control(r=-.32, P=.000) and decision making(r=-.31, P=.000). And decision making showed positively correlated with job control(r=.62, P=.000), and role conflict(r=.26, P=.003).

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.3
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• pp.199-207
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• 2003

In the study, the open area keeping a few visible satellites and the urban area covered with the high building, an electric pole were chosen far evaluation of accuracy of satellite positioning. First, suggest the validity of GPS/GLONASS, TS/RTK-GPS, and compared the accuracy with that of the classical surveying method. As a result, In static relative surveying, the difference of between the known cadastral supplementary control station and that of the acquired is 0.000∼.0006m in GPS alone, GPS/GLONASS, and In the RTK-GPS/TS, 0.010∼0.077m on the non-ambiguity fixed solutions in the urban area 0.008∼0.078m in the open area. it proved to be valid because it is within the allowed connecting errors, i.e 12cm on the baseline of loom in l/l,200 cadastral map.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.6
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• pp.589-594
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• 2015

In this paper, we described the Cramer-Rao Lower Bound (CLRB) performances of Time Difference of Arrival (TDOA) and Frequency Difference of Arrival (FDOA) methods when there are multiple emitters. The TDOA and FDOA values between two receivers can be simultaneously estimated by using the so-called Complex Ambiguity Function (CAF). In the case of multiple emitters, there exist Inter Symbol Interferences (ISIs) in the measurement data. Therefore, it is required to reduce the effect of ISI and provide a performance evaluation method of TDOA and FDOA estimations. In order to eliminate the ISIs, using of a filter bank before calculating CAF is proposed when the carrier frequencies of the emitters are different to one another. Angle of Arrival (AOA) or Received Signal Strength (RSS) methods before calculating CAF were proposed to reduce the ISIs when the carrier frequencies are the same. In order to evaluate the CRLB of TDOA and FDOA estimations, we employed the conditional probability distribution method and described the numerical comparison results.

• Journal of Satellite, Information and Communications
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• v.4 no.1
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• pp.21-27
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• 2009

In this paper, we introduce a simulation result of cross ambiguity function (CAF) using time difference of arrival and frequency difference of arrival. This method is generally used to find a geographical location of the unknown radio transmitter. If multiple signals with the same source information are arrived at a receiver via different paths, then they will have different time delays and Doppler shifts. We can estimate the CAF by using these characteristics, and estimate the location of the unknown transmitter. This paper introduces a technique to improve the estimation performance of CAF.

• The Journal of Information Technology
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• v.3 no.3
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• pp.27-37
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• 2000

Although an insurance criterion for reliance is unified, the difference in evaluation mechanism in every country is already ambiguity. In other words, the aspect of objectivity would be a little because it is true that the vulnerability evaluation include evaluator, scenario and tools (TSVES) applying in test, depth and scope of evaluation. But evaluation results can be difference in accordance with each evaluation elements. By using TSVES to evaluating network security vulnerability, first, we expected the evaluation results is impartiality, objectivity, repeatability, reproducibility, appropriateness and soundness of results. Second, it could be transferred manual ways into automation ways, and then expected easiness and safety of extension and modification in a quality of products as well as a dramatical reduction of waste of time and energy.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.81-86
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• 2003

As the utility value of GPS in surveying field is on the increase after the conversion into the world geodetic system, it is attracting the interest of many people involved in the application of GPS. In this study an algorithm was established settling ambiguity through LAMBDA techniques and the baseline processing program was developed for L1/L2 carrier phase using visual c++ 6.0, which is an object-oriented language. And the developed program proved that it maintained a difference of less than 3mm over the short baseline of 1.5m or shorter when compared with other commercialized programs.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.91-96
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• 2003

In static relative surveying, the difference of between the known cadastral supplementary control station and that of the acquired is 0.000∼0.0006m in GPS alone, GPS/GLONASS, and In the RTK-GPS/TS, 0.010∼0.077m on the non-ambiguity fixed solutions in the urban area, 0.008∼0.078m in the open area. it proved to be valid because it is within the allowed connecting errors, i.e 12cm on the baseline of l00m in 1/1,200 cadastral map.

• Language and Information
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• v.4 no.2
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• pp.107-124
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• 2000

This paper reports the syntactic distribution of amu-N-to/-ilato/-ina phrase, which are representative polarity sensitive items. (PSIs) in Korean, and ac- counts for their semantic characteristics in therms of "arbitrary choice quantification" and "concession" In the first section, we extensively illustrate the distributional behaviour of the PSIs in various costructions and roughly generalize the distribu- tion in terms of "(anti/non-) verdicality" Section 2 claims amu denotes an arbi- trary choice quantifier and the particles -to/-ilato/-ina as "concessive" markers, so the compounds denote a special element in a pragmatic scale determined by con- text/situation, Section 3. based on the pragmatics of scalar implicature, accounts for the apparent ambiguity of PSIs between "universal"and "existential"readings and further characterizes the difference among the concessive markers -to/-ilato/-ina in terms of "quantity/ quality scale."rkers -to/-ilato/-ina in terms of "quantity/ quality scale."

• Journal of Korean Library and Information Science Society
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• v.30 no.4
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• pp.163-181
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• 1999

The purpose of this study is to confirm what the stress factors are in performing their jobs among librarians in Public libraries. The study further investigates to figure out the difference of the degree in cognition of job stress according to demographic characteristics of individuals and the impacts of the stress factors on job satisfaction. A survey was conducted for the study sending questionaires to 113 librarians working in 14 Public libraries in Pusan. The results of the study are followings: 1) Females experience higher job stress than males. 2) The younger the age, the higher the job stress. Also, the shorter the year at work, the higher the job stress. 3) The lower the license class, the higher the job stress. Also, singles than married have higher job stress. 4) In the impacts of stress factors on job satisfaction, role conflict is the most powerful factor, and then role overload, career development, role underload, role ambiguity and interpersonal relation, each in order.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.319-320
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• 2008

In this paper, we propose a new frequency offset estimation algorithm for DBO-CSS which is a standard for wireless personal area network (WPAN). In DBO-CSS, there can be several integer multiples of $2{\pi}$ in the phase rotation caused by the frequency offset because of the long time difference between the samples of differential relation and the high permissible frequency offset of the crystal oscillators between the transmitter and the receiver. In this paper, we propose an estimation algorithm by using the relationships of each sub-chirp signals to find the integer part without phase ambiguity.