• Journal of Institute of Control, Robotics and Systems
• /
• v.19 no.8
• /
• pp.682-687
• /
• 2013

Navigation is a crucial capability for all types of manned or unmanned vehicles. However, vehicle navigation in underwater environments still remains a challenging problem since GPS signals for position fixes are not available in the water. Terrain-referenced underwater navigation is an alternative navigation technique that utilizes geometric information of the subsea terrain to correct drift errors due to dead-reckoning or inertial navigation. Terrain-referenced navigation requires the description of an undulating terrain surface as a mathematical function or table, which often leads to a highly nonlinear estimation problem. Recently, PFs (Particle Filters), which do not require any restrictive assumptions about the system dynamics and uncertainty distributions, have been widely used for nonlinear filtering applications. However, PF has considerable computational requirements which used to limit its applicability to problems of relatively low state dimensions. This study proposes the use of a Rao-Blackwellized particle filter that is computationally more efficient than the standard PF for terrain-referenced underwater navigation involving a moderate number of states, and its performance is compared with that of the extended Kalman filter algorithm. The validity and feasibility of the proposed algorithm is demonstrated through numerical simulations.

• English Language & Literature Teaching
• /
• no.6
• /
• pp.199-217
• /
• 2000

Relative pronoun that is one of the important relative pronouns but we have an impression that its scope of use has been somewhat narrowed. In the light of history of relative pronouns relative pronoun toot has the longest history of all relative pronouns and it was widely used even in Middle English and early Modem English. On The other hand, we can see that the relative use of that has been gradually weakened as the relative pronouns who and which has expanded their scope of use. It is quite natural that the scope of use of toot as a relative pronoun has been narrowed as who is mainly used in referring to person and which is mainly used in referring to things. And we can note that that is used only in restrictive clauses, not in nonrestrictive clauses, for that has a strong characteristics of relative conjunction in comparing with who and which. That as a relative pronoun still has its own weight because it can take an antecedent referring to person and thing. In particular, it is general tendency that who is used more frequently than that in the case of referring that it is not adequate for that to refer to things. In contrast, who has an advantage over that because the former originally refers only to person.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.1
• /
• pp.38-46
• /
• 2011

The OPRoS (Open Platform for Robotic Service) framework provides uniform operating environment for service robots. As an OPRoS-based service robot has to support real-time as well as non-real-time applications, application of Windows NT kernel based operating system can be restrictive. On the other hand, various benefits such as rich library and device support and abundant developer pool can be enjoyed when service robots are built on Windows NT. The paper presents a user-mode component scheduler of OPRoS, which can provide near real-time scheduling service on Windows NT based on the restricted real-time features of Windows NT kernel. The component scheduler thread with the highest real-time priority in Windows NT system acquires CPU control. And then the component scheduler suspends and resumes each periodic component executors based on its priority and precedence dependency so that the component executors are scheduled in the preemptive manner. We show experiment analysis on the performance limitations of the proposed scheduling technique. The analysis and experimental results show that the proposed scheduler guarantees highly reliable timing down to the resolution of 10ms.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.9
• /
• pp.57-64
• /
• 2017

CCSDS Standard is widely used in the international space telecommunication area. But standard recommendation of CCSDS is not restrictive, so, we can select an appropriate encryption protocol among the layer. For synchronization, encryption sync is attached in the beginning of the encrypted data. In the exceptional environmental condition, although the receiver can not decrypt the normal data, the sender have no conception of that situation. In this paper, we propose a two-stage SES alarmed link encryption synchronization method having optimized threshold value necessary to decide whether the receiver has a correct decryption or not. first, through the experiment of mutual relations between error rate and encryption synchronization detection error, we can predict worst communication environment for the selected encryption synchronization pattern. second, through the experiment for finding what number of consecutive frame synchronization error is an appropriate reference value and analysis of that experiment, we suggest an optimized threshold value for resynchronization request. lastly, through the output images we can predict the probability error that should be guaranteed by channel coder.

• Journal of the Korea Society of Computer and Information
• /
• v.10 no.6 s.38
• /
• pp.299-308
• /
• 2005

Recently, the standardization and computerization of franchise management have been necessitated from the specialization of industrial areas and the diversification of customer requirements. The existing ERP(Enterprise Resource Planning) systems are commercially used, but usually are restrictive solutions about manufactured goods and inventory management. etc. In this Paper, we propose an effective franchise management system Franchiser X1(FX1), which is a total component-based franchise management system for effectively supporting franchise management works, including the recruit of franchisees, the management of franchisees, consulting, education and A/S, bill collecting, and so on.

• Journal of Korea Society of Industrial Information Systems
• /
• v.12 no.1
• /
• pp.54-60
• /
• 2007

The Digital Multimedia Broadcasting(DMB) system is developed to offer high quality multimedia content to the mobile environment. The system adopts the MPEG-4 standard for the main video, audio and other media format. For providing interactive contents, it also adopts the MPEG-4 scene description that refers to the spatio-temporal specifications and behaviors of individual objects. With more interactive contents, the scene description also needs higher bitrate. However, the bandwidth for allocating meta data, such as scene description is restrictive in the mobile environment. On one hand, the DMB terminal renders each media stream according to the scene description. Thus the binary format for scene(BIFS) stream corresponding to the scene description should be decoded and parsed in advance when presenting media data. With this reasoning, the transmission delay of the BIFS stream would cause the delay in transmitting whole audio-visual scene presentations, although the audio or video streams are encoded in very low bitrate. This paper presents the effective optimization technique in adapting the BIFS stream into the expected bitrate without any waste in bandwidth and avoiding transmission delays inthe initial scene description for interactive DMB content.

• Korean Journal of Child Studies
• /
• v.36 no.3
• /
• pp.175-194
• /
• 2015

The purpose of this preliminary study was to investigate the validity of the 'Attachment Q-set' as a measuring tool for 5 years attachment stability. The subjects comprised 18 boys and 15 girls aged 5 in a daycare center in G city, in Kyongnam. The instruments used in this study were 'Attachment Q-set', ASCT, and IPPA-R. Based on experts' rating, the Q-set was modified, reducing it from 90 to 75 items, and used a Likert 5-points scale. ASCT scores as well as types were compared with the scores of the Q-set and IPPA-R. The attachment type was classified into either secure or insecure. The IPPA-R score of the secure infants was significantly higher than the insecure, and correlated with the ASCT score. However, there was no significant correlation between the Q-set score with the attachment types or the ASCT scores. The Q-set scores were partially correlated with the IPPA-R. This results were discussed in terms of the Q-set's invalidity for rating attachment levels of 5 years as well as the limitations imposed by the subjects' restrictive numbers.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2000.03a
• /
• pp.65-84
• /
• 2000

Europe and US which have more restrictive regulations than Korea about the noise and vibration during construction are using Auger-cast Pile to reduce the problem relating with noise and vibration. However Auger-cast Pile has problems like difficult quality control and low bearing capacity. In Europe, Displacement in-situ concrete Pile has been used to sove that problems since 1990s, and Korea has performed the test construction in 1997 and it has been used as the real structural foundation since 1998. Test and real construction results verified that the allowable capacity of the pile(diameter = 410mm) is between 70 and 100ton. Though De Beer & Van Imps design method utilizing CPT result is used to calculate the bearing capacity of the Displacement in-situ Pile, Korea is dependant upon the SPT as the sounding test, so design method utilizing SPT result is necessary to promote the application of the pile. To find out reasonable design method using SPT result, rearing capacity of the pile constructed in sand and clay in Korea was calculated using Meyerhof, SPT-CPT translation method, Nordlund, Douglas and DM-7 method, and the calculation results were compared to the load test result. Analysis result shows that SPT-CPT translation method is more reliable than others and economical design can be possible because it considers efficiently the friction capacity of Displacement in-situ Pile.

• The Journal of Fisheries Business Administration
• /
• v.47 no.4
• /
• pp.15-30
• /
• 2016

Changes in marketing environment have made it feasible for functions and roles of marketing subjects who participated in marketing routes to be changed. However, there has not been a study to prove it or to deal with newly required functions. Hereupon, this study has specifically investigated and analyzed marketing functions and performance on marketing associates for seafood in Busan in order to identify how marketing functions influenced on marketing performance. Marketing function might differently influence on the performance depending on the difference of business type. Results of verifying the hypothesis are as follows. As for variables that influenced on wholesaler groups, marketing, product development+investment, information-sharing, and trade functions turned out to be influential. Among wholesaler groups, marketing, sorting, collection, market frontier+product development, integral distribution, information-sharing, and finance functions turned out to be influential. In addition to these basic results, another difference industries, restrictive range of activities, the differences in handling goods, such as by correspondence of the results to changes in the distribution environment, from the results of the present study it is possible to guess.

• Journal of Families and Better Life
• /
• v.23 no.5 s.77
• /
• pp.181-190
• /
• 2005

The purpose of this study was to investigate the characteristics of leisure behavior of the five-day workweek company employees for developing leisure facilities in residential environment. The questionnaire survey was used. The subjects of questionnaire survey were 247 staffs of 4 banks. The questionnaire consisted of leisure time, the cost of leisure, consciousness of leisure, actual condition and need of leisure activities and spaces, leisure satisfaction and limitation on leisure. Frequency, percentage, and mean, correlation, $x^2-test$, and factor analysis were used for data analysis. The major results were as follows. 1) Leisure is necessary to strengthen the unity of family and cultivate the sentiment. 2) The degree of satisfaction of leisure facilities was lower than neutral. The satisfaction of leisure facilities related with cost, time of leisure, information of leisure facilities and program, and leisure environment. 3) Present leisure behavioral characteristics were restrictive and passive. However, the subjects showed hopes to increase their leisure activities and to engage in diverse forms of leisure in the future. Also, they showed an increased desired ratios in participating in each leisure activities. 4) In terms of location, they needed leisure facilities which was closer to their house.