• Structural Engineering and Mechanics
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• v.3 no.2
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• pp.107-120
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• 1995

A soil-structure interaction formulation is used here which is based on consideration of the dynamics of the structure with a free, rather than a fixed, base. This approach is shown to give a quite simple procedure for coupling the dynamic characteristics of the structure to those of the foundation and soil in order to obtain a matrix formulation for the complete system. In fixed-base studies it is common to presume that each natural mode of the structure has a given fraction of critical damping, and since the interaction formulation uses a free-base model, it seems natural for this situation to assign the equal modal damping values to free-base modes. It is shown, though, that this gives a structural model which is significantly different than the one having equal modal damping in the fixed-base modes. In particular, it is found that the damping matrix resulting in equal modal damping values for free-based modes will give a very significantly smaller damping value for the fundamental distortional mode of the fixed-base structure. Ignoring this fact could lead one to attribute dynamic effects to interaction which are actually due to the choice of damping.

• The Transactions of the Korea Information Processing Society
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• v.7 no.10
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• pp.3075-3085
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• 2000

According to distributed, large-caled environment of software development and operation, the elicitation and specivication of correct and complete requrement is the most important factor for the system. In addition contiuous and dramatic systerm canging requests in cooperative environment with internet require more efficient, requirement management. In this paper we detine the specification architecture and techruques for requrements, so that we improve the efficiency ofnatural language-based requirement speciticationand management in a cooperatie work environment. Also, we propose a software requirement engineering process model and environment based on requirements in a CSC@(Computer Supported Cjooperative Work) environment, therefore transfer them into analysis phase.

• Advances in aircraft and spacecraft science
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• v.7 no.3
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• pp.251-269
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• 2020

Euclid is an optical/near-infrared survey mission of the European Space Agency (ESA) to investigate the nature of dark energy, dark matter and gravity by observing the geometry of the Universe and the formation of structures over cosmological timescales. The Euclid spacecraft mechanical architecture comprises the Payload Module (PLM) and the Service Module (SVM) connected by an interface structure designed to maximize thermal and mechanical decoupling. This paper shortly illustrates the mechanical system of the spacecraft and the mechanical verification philosophy which is based on the Structural and Thermal Model (STM), built at flight standard for structure and thermal qualification and the Proto Flight Model (PFM), used to complete the qualification programme. It will be submitted to a proto-flight test approach and it will be suitable for launch and flight operations. Within the overall verification approach crucial mechanical tests have been successfully performed (2018) on the SVM platform and on the sunshield (SSH) subsystem: the SVM platform static test, the SSH structure modal survey test and the SSH sine vibration qualification test. The paper reports the objectives and the main results of these tests.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.1
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• pp.211-232
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• 2024

In this paper, we consider the resource allocation and offloading decisions of device-to-device (D2D) cooperative UAV-assisted mobile edge computing (MEC) system, where the device with task request is served by unmanned aerial vehicle (UAV) equipped with MEC server and D2D device with idle resources. On the one hand, to ensure the fairness of time-delay sensitive devices, when UAV computing resources are relatively sufficient, an optimization model is established to minimize the maximum delay of device computing tasks. The original non-convex objective problem is decomposed into two subproblems, and the suboptimal solution of the optimization problem is obtained by alternate iteration of two subproblems. On the other hand, when the device only needs to complete the task within a tolerable delay, we consider the offloading priorities of task to minimize UAV computing resources. Then we build the model of joint offloading decision and power allocation optimization. Through theoretical analysis based on KKT conditions, we elicit the relationship between the amount of computing task data and the optimal resource allocation. The simulation results show that the D2D cooperation scheme proposed in this paper is effective in reducing the completion delay of computing tasks and saving UAV computing resources.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.4
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• pp.769-781
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• 1997

The purpose of this research is to show how to use the patternist's CAD system in order to make design patterns efficiantly. Using the PAD System Technologies company's PAD System Module, which is very officiant in designing patterns, the basic pattern or design pattern can be designed and applyed to the Sample Module, thus, then it could manufacture, retouch or choose a model, making it posible to go to the next level which is seam patterns for industrial use. By understanding the change of the design that is chosen through the design pattern making and Sample Module process', this study is presentated a plan on how to utilize the patternist's working adaption ability by the CAD system, and also considered the problems in using it. Ability of Design Confrontation of CAD System: 1) The result of an operation can be saved and retouched. On a saved list the patterns can be chosen and changed, thus, making it posible to complete a design very quickly. 2) When sewing every designed pattern in Sample Module, the model can be operated merely by selecting each sewing position, thus creating the same effect of a designer's muslin sample process in a much lesser time. Point at issue in the utilization CAD system: 1) When combining two darts into one place the amounts of darts that are already these have to be erasers, and then, the two darts points are moved that place, thus, containing them, which is very conplicated. 2) When making a gathering, because system can only be recognized in a opend line, the pattern should be separated in order to put a gathering inside a pattern. 3) In order to readjust the amounte of dart. The dart is erased first and then made new dart again. 4) When making tucks in a Sample Module, the form that gets narrow towards the pivot point can not be recognized so the sewing lines of the tucks is adjusted into parallel lines. 5) The Sample Module 3D operation can not attach the bodice to the shirts, instead they become fixed into each other. In the case of shoulder line tucks the amounts of pleats can not be expanded draperary naturally, thus, making it hard to showing the silhouette accurately. If these problems are solved, especially if the silhouette of a model can be created to have natural drapery in the 3D Module, models can be shown on the screen in possible to compare and examine even a change of a detail, by designing this 3D Module Production sample process will be more effective, thus, making the CAD system more useful in sewing design process.

• Korean Journal of Social Welfare
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• v.43
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• pp.76-105
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• 2000

In the last two decades, the welfare states have undergone the changes of restructuring towards two ways. One is a restructuring of workfare and the other is a restructuring of the gender model of welfare state. In Korea, the workfare is reflecting on the DJ Welfarism 'Productive Welfare', but the gender model has a little effect on the public policies. By the way, It is imported that has the gender perspective in approaching the self-supporting program in the public assistance representing of the DJ Welfarism. Because almost 60% of the beneficiaries of the program are women. The Gender-mainstreaming strategy criticizes for the laws, the public policies, the public programs that considered gender-neutral or gender-blinded, and then complete the equality between women and men through the modification or development of those. The approach of Gender-mainstreaming is very important strategy for not only women who are self-reliance recipient but also successful settlement of self-supporting program. Nowadays that program is not execute yet. Then we hardly have information about recipients and the results that expected from that. At this point of gender-mainstreaming, this report suggest the strategy to development and settlement of the self-supporting program in the basics of analysis for the low-income unemployed and the government policy response to unemployment. For the gender models of the self-supporting program, the most important thing is throwing the male breadwinner model and adoption the dural-earner model (the gender model) about that program. Then we must produce gender-statistics data, develop programs for public work, job replacement, job training, evaluating system, etc. with gender perspective.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.2 no.2
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• pp.63-81
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• 2008

WiMAX has been introduced as a competitive alternative for metropolitan broadband wireless access technologies. It is connection oriented and it can provide very high data rates, large service coverage, and flexible quality of services (QoS). Due to the large number of connections and flexible QoS supported by WiMAX, the uplink access in WiMAX networks is very challenging since the medium access control (MAC) protocol must efficiently manage the bandwidth and related channel allocations. In this paper, we propose and investigate a cost-effective WiMAX bandwidth management scheme, named the WiMAX partial sharing scheme (WPSS), in order to provide good QoS while achieving better bandwidth utilization and network throughput. The proposed bandwidth management scheme is compared with a simple but inefficient scheme, named the WiMAX complete sharing scheme (WCPS). A maximum entropy (ME) based analytical model (MEAM) is proposed for the performance evaluation of the two bandwidth management schemes. The reason for using MEAM for the performance evaluation is that MEAM can efficiently model a large-scale system in which the number of stations or connections is generally very high, while the traditional simulation and analytical (e.g., Markov models) approaches cannot perform well due to the high computation complexity. We model the bandwidth management scheme as a queuing network model (QNM) that consists of interacting multiclass queues for different service classes. Closed form expressions for the state and blocking probability distributions are derived for those schemes. Simulation results verify the MEAM numerical results and show that WPSS can significantly improve the network’s performance compared to WCPS.

• Journal of International Society for Simulation Surgery
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• v.2 no.1
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• pp.13-16
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• 2015

Purpose We conducted a study on the reconstruction of the head's shape in 3D using the ToF depth sensor. A time-of-flight camera (ToF camera) is a range imaging camera system that resolves distance based on the known speed of light, measuring the time-of-flight of a light signal between the camera and the subject for each point of the image. The above method is the safest way of measuring the head shape of plagiocephaly patients in 3D. The texture, appearance and size of the head were reconstructed from the measured data and we used the SDF method for a precise reconstruction. Materials and Methods To generate a precise model, mesh was generated by using Marching cube and SDF. Results The ground truth was determined by measuring 10 people of experiment participants for 3 times repetitively and the created 3D model of the same part from this experiment was measured as well. Measurement of actual head circumference and the reconstructed model were made according to the layer 3 standard and measurement errors were also calculated. As a result, we were able to gain exact results with an average error of 0.9 cm, standard deviation of 0.9, min: 0.2 and max: 1.4. Conclusion The suggested method was able to complete the 3D model by minimizing errors. This model is very effective in terms of quantitative and objective evaluation. However, measurement range somewhat lacks 3D information for the manufacture of protective helmets, as measurements were made according to the layer 3 standard. As a result, measurement range will need to be widened to facilitate production of more precise and perfectively protective helmets by conducting scans on all head circumferences in the future.

• Journal of Korea Multimedia Society
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• v.5 no.3
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• pp.290-297
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• 2002

The appearance of web technology has accelerated the role of the application of multimedia technology, computer communication technology and multimedia application contents. Recently WBI model which is based on web has been proposed in the part of the new activity model of teaching-teaming. How to learn and evaluate is required to consider individual learner's learning level. And it is recognized that the needs of the efficient and automated education agents in the web-based instruction is increased But many education systems that had been studied recently did not service fluently the courses which learners had been wanting and could not provide the way for the learners to study the learning weakness which is observed in the continuous feedback of the course. In this paper we propose design of multi-module system for course scheduling of learner-oriented using weakness analysis algorithm. First proposed system monitors learner's behaviors constantly, evaluates them, and calculates his accomplishment and weakness. From this weakness the multi-agent prepares the learner a suitable course environment to strengthen his weakness. Then the learner achieves an active and complete teaming from the repeated and suitable course.

• The KIPS Transactions:PartB
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• v.8B no.6
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• pp.595-600
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• 2001

Recently, WBI model which is based on web has been proposed in the part of the new activity model of teaching-learning. The demand for the customized coursewares which is required from the learners is increased, the needs of the efficient and automated education agents in the web-based instruction are recognized. But many education systems that had been studied recently did not service fluently the courses which learners had been wanting and could not provide the way for the learners to study the learning weakness which is observed in the continuous feedback of the course. In this paper we propose design of multi-agent system for course scheduling of learner-oriented using weakness analysis algorithm. First, proposed system monitors learner's behaviors constantly, evaluates them, and calculates his accomplishment. From this accomplishment, the multi-agent schedules the suitable course for the learner. The learner achieves an active and complete learning from the repeated and suitable course.