• Journal of Institute of Control, Robotics and Systems
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• v.7 no.12
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• pp.1036-1043
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• 2001

It is well-known that positioning accuracy can be improved by the use of carrier phase of GPS up to the centimeter level. In order to obtain good accuracy, we need to know integer ambiguity in the carrier phase accurately. In this paper, we propose a fast ambiguity determination method(FADM) which combines Kalman filtering and the search method, and show the improvement of the positioning performance by static and kinematic simulation compared with known methods such as Kalman filtering, LSAST (Least Squares Ambiguity Search Technique), ARCE(Ambiguity Resolution with Constratint Equation), LLL(Lenstra, Lenstra, and Lovasz) algorithms.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.361-371
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• 2013

Public domain defect data sets, such as NASA data sets which are available from the NASA MDP and PROMISE repositories, make it possible to compare the results of different defect prediction models by using the same data sets. This means that repeatable and general prediction models can be built. However, some recent studies have raised questions about the quality of two versions of NASA data set, and made new cleaned data sets by applying their data cleaning processes. We find that there are two ways in the NASA MDP versions to determine the defectiveness of a module, 0 or 1, and the two results are different in some cases. This serious problem, to our knowledge, has not been addressed in previous studies. To handle this ambiguity problem, we define two kinds of module defectiveness and two conditions that can be used to determine the ambiguous cases. We meticulously analyze 5 projects among the 13 NASA projects by using our ambiguity analysis method. The results show that JM1 and PC4 are the best projects with few ambiguous cases.

• Journal of Navigation and Port Research
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• v.39 no.1
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• pp.15-21
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• 2015

In high precision positioning systems based on GNSS, ambiguity resolution is an important procedure. Correct ambiguity leads to positioning results which have high precision between millimeters and centimeters. However, when the ambiguity is determined incorrectly, ensuring accuracy and precision of the positioning result is impossible. An ambiguity validation test is required to obtain correct ambiguity when ambiguity resolution is performed based on the ILS (Integer Least Squares), which shows the best performance in point of theory and experiment when compared with other methods such as IR (Integer Rounding) and IB (Integer Bootstrapping). Comparison between the candidates of the validation test is needed to judge ambiguity correctly, because ILS searches for candidates of integer ambiguity, unlike other methods which calculate only one integer ambiguity. We analyzed the experimental performance of ambiguity validation tests. R-ratio, F-ratio and W-ratio were adopted for analysis. The performance of validation tests was evaluated by classifying normal operation, detection, missed detection and false alarm. As a result, strengths and weaknesses of validation tests was showed to experimental. we concluded that validation tests must be selected according to environment.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.18-27
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• 2020

This study is to corroborate the relationship between organizational size and performance in the Korean government context. Hence, this study aims to advance research on the relationship between organization size and performance by considering mediating variable: organizational goal ambiguity, which helps understand how organizational size affects organizational goal ambiguity in government and the organizational goal ambiguity has an influence on organizational performance. Bases on theoretical review, we assume that there is the inverted U-shaped relationship between the number of employees and budget size and organizational performance. From the results of path analysis, it shows that organizational size in the Korean government has a negative correlation, "a linear relationship", with organizational performance. Budget size has mediating variables, but the number of employees not. We try to suggest implications on the relationship between organizational size and performance in terms of theoretical perspectives in the context of the Korean government.

• Journal of Family Resource Management and Policy Review
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• v.14 no.3
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• pp.165-181
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• 2010

The purpose of this study was to examine the mediating effects of role ambiguity on the relationship between self-efficacy and job satisfaction of visiting supervisors for multicultural families. The subjects were 243 visiting supervisors for multicultural families. The data were analyzed with SPSS Win 15.0 using Cronbach's ${\alpha}$, hierarchical multiple regression and path analysis. The findings showed that both self-efficacy and role ambiguity exerted a significant effect on the job satisfaction of visiting supervisors for multicultural families. Further, it is important to note that the effect of self-efficacy on job satisfaction was mediated by role ambiguity. The study discussed implications in terms of job satisfaction of visiting supervisors for multicultural families.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.95-102
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• 2005

The purpose of this study was to analyze the ambiguity of the boundary through the composition of section. The building means the compose of the inside space by physical shell. Inside space that has boundary factors like floor, wall, roof and column is surrounded outside space. The factors which compose the boundary was expressed by architects as various analysis, but it has changed as changing of paradigm and information revolution. The inside space and outside space were connected through the system arrangement, so various space could construct by an aspect of relation. The history of architecture was written as the establishment of in-out space by architectural boundary factors, but the space could not divide definitely, composed complex structure, could experience various recognition. The existing study which is focused on Ambiguity of the Boundary is just focused on contemporary architecture. Ambiguity of the Boundary is developed by using glass. The transparency of glass removed the boundary of space, so it can be created free wall, continuity of view. It was Influenced the boundary of the sight and changed the expression of boundary between the space. This study is to analyze the change of boundary awareness and find the ambiguity of boundary in the section.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.146-146
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• 2000

This paper presents field test results of the GPS precise positioning using carrier phase observable. The Least-squares AMBiguity Decorrelation Adjustment(LAMBDA) method is implemented to resolve integer ambiguity problem for two epoch Ll carrier phase measurement data. Field test results show that the GPS precise positioning of cm-level accuracy is obtainable with conventional low cost, single frequency C/A code GPS receivers.

• Management & Information Systems Review
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• v.19
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• pp.171-197
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• 2006

The purpose of this study is to analyze how the task group functioning and need styles have influence on role conflict and role ambiguity as the employee's personality engaged in the service industry such as a hotel. This study uses the hierarchical regression analysis method. Data were collected by the survey method from employees engaged in the service industry such as a hotel located Seoul, the Province of Gyeonggi, and the Province of Gangwon. The study result shows that to the employees in the type A and type X styles, the task group functioning and need styles are not significantly related to the role conflict. But to the employees in the type B style, the task group functioning and need styles are significantly related to the role conflict. And the result shows that to the employees in the type B style, the lower the faith in peers and management, the more the role conflict occur. On the other hand, the study result shows that to the employees in the type A styles, the task group functioning is significantly related to the role ambiguity. And to the employees in the type B style, the higher the faith in peers and management, the more the role ambiguity occur. On the contrary, to the employees in the type X style, need styles are significantly related to the role ambiguity. But to the employees in the type X style, the higher the need for achievement, the more the role ambiguity occur. On the other hand, the study result shows that to the employees in the type B styles, the task group functioning and need styles are significantly related to the role ambiguity. And to the employees in the type B style, the higher the need for achievement, the more the role ambiguity occur or the lower the confidence in peers and management, the more the role ambiguity occur. Although this study provides several managerial implications, this study has some limitations. Specifically data were collected from only the hotel industry in Seoul, the Province of Gyeonggi, and the Province of Gangwon. In spite of the limitations, the study results could be used valuably in case of the personnel managers which manage the employees under the conflict situations.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.114.1-114
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• 2001

GPS Receiver gives pseudorange Doppler and integrated carrier phase for measurements to compute navigation information. Thought the integrated carrier phase can be transfer to the equal domain as pseudorange by multiplying the wave length of the received signal, in order to get position information from the carrier phase measurements the integer ambiguity should be resolved. And differencing technique is generally used to eliminate the common error terms of the integrated carrier phase measurements between robber and server. In short baseline double-differencing operation has effect on elimination the common biases for both stations and thus ambiguity resolution are to be reliable. But the baseline increases, the integer ambiguity resolution is hardly, due to the correlated common error is increase ...

• Journal of electromagnetic engineering and science
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• v.13 no.4
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• pp.251-258
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• 2013

A procedure for antenna parameter selections is proposed that considers the relationships between synthetic aperture radar performance and the antenna parameters of a parabola-type reflector antenna with a central flat dish. The effects of a central dish designed for weight reduction on the antenna beam pattern are also quantitatively analyzed using commercially available software based on the physical optics algorithm. The results of the theoretical analysis and simulation predict that a larger size of the central dish results in an increase in the sidelobe level, which is the reason for the increase in two important ambiguities, such as range ambiguity ratio (RAR) and azimuth ambiguity ratio (AAR). The dependence of RAR and AAR on Pulse repetition frequency is also analyzed and discussed.