• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3584-3602
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• 2022

NFV realizes flexible and rapid software deployment and management of network functions in the cloud network, and provides network services in the form of chained virtual network functions (VNFs). However, using VNFs to provide quality guaranteed services is still a challenge because of the inherent difficulty in intelligently scaling VNFs to handle traffic fluctuations. Most existing works scale VNFs with fixed-capacity instances, that is they take instances of the same size and determine a suitable deployment location without considering the cloud network resource distribution. This paper proposes a traffic forecasted assisted proactive VNF scaling approach, and it adopts the instance capacity adaptive to the node resource. We first model the VNF scaling as integer quadratic programming and then propose a proactive adaptive VNF scaling (PAVS) approach. The approach employs an efficient traffic forecasting method based on LSTM to predict the upcoming traffic demands. With the obtained traffic demands, we design a resource-aware new VNF instance deployment algorithm to scale out under-provisioning VNFs and a redundant VNF instance management mechanism to scale in over-provisioning VNFs. Trace-driven simulation demonstrates that our proposed approach can respond to traffic fluctuation in advance and reduce the total cost significantly.

• Wind and Structures
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• v.37 no.3
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• pp.245-254
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• 2023

In this paper, the wind-induced response of Jiayuguan wooden building (world cultural heritage) in Northwest China was studied. ANSYS finite element software was used to establish four kinds of building models under different working conditions and carry out modal analysis. The simulation results were compared with the field dynamic test results, obtaining the model which reflects the real vibration characteristics of the wooden tower. Time history data of fluctuating wind speed was obtained by MATLAB programming. Time domain method and ANSYS were used to analyze the wind-induced vibration response time history of Jiayuguan wooden building, obtaining the displacement time history curve of the structure. It was suggested that the wind-induced vibration coefficient of Jiayuguan wooden building is 1.76. Through analysis of the performance of the building under equivalent static wind load, the maximum displacement occurs in the three-story wall, gold column and the whole roof area, and the maximum displacement of the building is 5.39 cm. The ratio of the maximum stress value to the allowable value of wood tensile strength is 45 %. The research results can provide reference for the wind resistant design and protection of ancient buildings with similar structure to Jiayuguan wooden tower.

• Journal of Electrical Engineering and information Science
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• v.1 no.2
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• pp.1-8
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• 1996

This paper presents a text-driven discourse analysis system, called DPAS. DPAS constructs a discourse structure by weaving together clauses in the text by finding discourse relations between a clause and the clauses in a context. The basic processing model of DPAS is based on the stack based model of discourse analysis suggested by Grosz and Sidner. We extend the model with dynamic programming method to handle various discourse ambiguities effectively and efficiently. We develop the idea of a context space to keep all information of a context. DPAS parses a text by considering all possible discourse relations between a clause and a context. Since different discourse relations may result in different states of a context, DPAS maintains multiple context spaces for an ambiguous text. Since maintaining all interpretations until the whole text is processed requires too much computing resources, DPAS uses the idea of depth-limited search to limit the search space. If there is more than one discourse relation between an input clause and a context, DPAS constructs context spaces one context space for each discourse relation. Then, DPAS applies heuristics to choose the most desirable context space after it processes some more input clauses. Since the basic idea of DPAS is domain independent, although we used descriptive texts to demonstrate DPAS, we believe the idea of DPAS can be extended to understand other styles of texts.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.3
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• pp.158-167
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• 2017

Internet-based social and interactive video applications have become major constituents of the envisaged applications for next-generation multimedia networks. However, inherently dynamic network conditions, together with varying user expectations, pose many challenges for resource allocation mechanisms for such applications. Yet, in addition to addressing these challenges, service providers must also consider how to mitigate their operational costs (e.g., energy costs, equipment costs) while satisfying the end-user quality of service (QoS) expectations. This paper proposes a heuristic solution to the problem, where the energy incurred by the applications, and the monetary costs associated with the service infrastructure, are minimized while simultaneously maximizing the average end-user QoS. We evaluate the performance of the proposed solution in terms of serving probability, i.e., the likelihood of being able to allocate resources to groups of users, the computation time of the resource allocation process, and the adaptability and sensitivity to dynamic network conditions. The proposed method demonstrates improvements in serving probability of up to 27%, in comparison with greedy resource allocation schemes, and a several-orders-of-magnitude reduction in computation time, compared to the linear programming approach, which significantly reduces the service-interrupted user percentage when operating under variable network conditions.

• The KIPS Transactions:PartD
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• v.16D no.1
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• pp.83-92
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• 2009

Complicated business logic makes program complexity more complicated. It's inevitable that the program must undergo reengineering processes all the way of in its lifetime. Hot spot analysis that has diverse purposes is getting an important question more and more. As a rule, reengineering process is done by UML model-based approach to analyze the legacy system. The smallest fragment of targets to be analysed is unit, that is function or class. Today's software development is to deal with huge change of software product and huge class including heavy quantity of LOC(Lines Of Code). However, analysis of unit is not precise approach process for reliable reengineering consequence. In this paper, we propose very precise hot spot analysis approach using Aspect-Oriented Programming languages, such as AspectJ. Typically the consistency between UML and source is needed code to redefine the modified library or framework boundaries. But reengineering approach using AOP doesn't need to analyze UML and source code. This approach makes dynamic event log data that contains detailed program interaction information. This dynamic event log data makes it possible to analyze hot spot.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.1
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• pp.29-37
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• 1989

This paper presents an application of the extended DP matching method to the on-line recognition of cursive Hangeul (Korean characters). We decrease the number of matching's objects by performing rough classification matching which makes the best use of features in the first and the last segment of Hangeul. By adding the extraction function of the basic character patterns to DP matching method, we try to calculate precisely the difference among Hangeul. The extraction of the basic character patterns is done by examining the features of segments in character. Applying the extended DP matching method to the on-line recognition of cursive Hangeul, absorption of writing motion and stable separation of strokes can be performed with flexibility.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.12
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• pp.637-644
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• 2004

This paper proposes an expert system with the knowledge learning capability which can enhance the safety and effectiveness of substation operation in the automated substation as well as existing substation by inferring multiple events such as main transformer fault, busbar fault and main transformer work schedule under multiple inference mode and multiple objective mode and by considering totally the switch status and the main transformer operating constraints. Especially inference mode includes the local minimum tree search method and pattern recognition method to enhance the performance of real-time bus reconfiguration strategy. The inference engine of the expert system consists of intuitive inferencing part and logical inferencing part. The intuitive inferencing part offers the control strategy corresponding to the event which is most similar to the real event by searching based on a minimum distance classification method of pattern recognition methods. On the other hand, logical inferencing part makes real-time control strategy using real-time mode(best-first search method) when the intuitive inferencing is failed. Also, it builds up a knowledge base or appends a new knowledge to the knowledge base using pattern learning function. The expert system has main transformer fault, main transformer maintenance work and bus fault processing function. It is implemented as computer language, Visual C++ which has a dynamic programming function for implementing of inference engine and a MFC function for implementing of MMI. Finally, it's accuracy and effectiveness is proved by several event simulation works for a typical substation.

• Water for future
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• v.18 no.2
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• pp.163-174
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• 1985

This study aims at the development of a technique for the optimal water allocation by applying Dynamic Programming Model for the effective usage and rational allocation of water resources, in case of which limited water resources in river basin should be used in several stages. In analytical procedure the possible allocable area was firstly zoned into the four areas: Pohang area ($C_1$), Yeungcheon area ($C_2$), Gyeungsan area ($C_3$), Daegu area ($C_4$), which are located between the Yeongcheon dam and the confluence of the lower Kumho river and the main course of the Nakdong river. Secondly, a return function was determined on the basis of the correlation between the GRP in each area and the amount of water used to it. A DP Model, finally, was applied to the allocation of the water resources according to both their usage and the areas. As a result, the fact has been found that when allocating by the area, $C_1$ could be possibly supplied only with the water resources avaiable from the Yeungchon dam, and the maximum units supplied to $C_1$ should be 240 units ($1unit=10^3㎥$ per day), beyond which we ought to develop an alternative water resources. Also, the return from the allocation by the usage exceeded the one from it by the area. At the same time it was more profitable to limit the water supply to $C_1$ into 217 units. In the allocation by the area 240 units and 80 units, if only the water resources available from the Yeungcheon dam used, and 360 units and 80 units if the Doil dam used additionally, could be supplied to $C_1$ and the lower region respectively. In the allocation by the usage 103 units for industrial water with 33 units for both domestic and commercial water and 183 units, if only the water resources available from the Yeungcheon dam used, and 103 units with 33 units and 304 units, if the Doil dam taken into consideration additionally, could be supplied to $C_1$ and the lower region respectively. Therefore, much more water could be allocated to the region of lower Kumho river if the method of water allocation by the usage.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.34-43
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• 2012

Determining the similarity between two strings can be applied various area such as information retrieval, spell checker and spam filtering. Similarity calculation between Korean strings based on dynamic programming methods firstly requires a definition of the similarity between phonemes. However, existing methods have a limitation that they use manually set similarity scores. In this paper, we propose a method to automatically calculate inter-phoneme similarity from a given set of variant words using a PAM-like probabilistic model. Our proposed method first finds the pairs of similar words from a given word set, and derives derivation rules from text alignment results among the similar word pairs. Then, similarity scores are calculated from the frequencies of variations between different phonemes. As an experimental result, we show an improvement of 10.1%~14.1% and 8.1%~11.8% in terms of sensitivity compared with the simple match-mismatch scoring scheme and the manually set inter-phoneme similarity scheme, respectively, with a specificity of 77.2%~80.4%.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.121-125
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• 2007

This paper proposes automatic generation method of proxy client code to automation of web service selection process through a monitoring agent. The technique of this paper help service consumer to provide source code of proxy client as it bring an attribute value of specific element of WSDL document using template rule. Namely, a XSLT script file provide code frame of dynamic invocation interface model. The automatic code generation technique need to solving starvation status of selection architecture. It is required to creating request HTTP message for every service on the result of search. The created proxy client program code generate dummy message about services. The proposed client code generation method show us a possibility of application in the automatic generation programming domain.