• Educational Technology International
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• v.9 no.1
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• pp.79-96
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• 2008

The issue of connection between entities has a lengthy history in educational research, especially since it provides the necessary bridge between base and target in analogical transfer. Recently, the connection has been viewed through the application of technology to bridge between sequences in order to be cognitively useful. This study reports the effect of sequence type (AT vs. TA) and connection type (fading vs. popping) on the achievement and analogical transfer in a multimedia application. In the current research, 10th -grade and 11th -grade biology students in Korea were randomly assigned to five groups to test the effects of presentation sequence and entity connection type on analogical transfer. Consistent with previous studies, sequence type has a significant effect: analogical transfer performance was better when base representations were presented first followed by target representations rather than the reverse order. This is probably because presenting a familiar base first helps in understanding a less familiar target. However, no fully significant differences were found with the entity connection types (fading vs. popping) in analogical transfer. According to the Markman and Gentner's (2005) spatial model, analogy in a space is influenced only by the differences between concepts, not by distance in space. Thus connection types fail on the basis of this spatial model in analogical transfer test. The findings and their implications for sequence and connection research and practice are discussed. Leveraging on the analogical learning process, specific implications for scaffolding learning processes and the development of adaptive expertise are drawn.

• The Journal of the Acoustical Society of Korea
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• v.42 no.2
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• pp.94-101
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• 2023

A deep neural network composed of encoders and decoders, such as U-Net, used for speech enhancement, concatenates the encoder to the decoder through skip-connection. Skip-connection helps reconstruct the enhanced spectrum and complement the lost information. The features of the encoder and the decoder connected by the skip-connection are incompatible with each other. In this paper, for complex-valued spectrum based speech enhancement, Self-Attention (SA) method is applied to skip-connection to transform the feature of encoder to be compatible with the features of decoder. SA is a technique in which when generating an output sequence in a sequence-to-sequence tasks the weighted average of input is used to put attention on subsets of input, showing that noise can be effectively eliminated by being applied in speech enhancement. The three models using encoder and decoder features to apply SA to skip-connection are studied. As experimental results using TIMIT database, the proposed methods show improvements in all evaluation metrics compared to the Deep Complex U-Net (DCUNET) with skip-connection only.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5B
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• pp.465-475
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• 2004

Transport Control Protocol (TCP) has been implemented in software running on CPU in end systems, and the protocol processing has appeared as a new bottleneck due to advanced link technology. TCP processing is a critical issue in Storage Area Network (SAN) such as iSCSL, and the overall performance of the Storage Area Network heavily depends on speed of TCP processing. TCP Engine implemented in hardware reduces the load of CPU in end systems as well as accelerates the protocol processing, and hence high speed data processing is achieved. In this paper, we have proposed a hardware engine for TCP processing. TCP engine consists of three major block, TCP Connection block Rx TCP block and Tx TCP block TCP Connection block is responsible for managing TCP connection states. Rx TCP block is responsible for receive flow which receives packets from network and sends to CPU. Rx TCP performs header and data processing and sends header information to TCP connection block and Tx TCP block It also assembles out-of-ordered data to in-ordered before it transfers data to CPU. Tx TCP block is responsible for transmit flow which transfers data from CPU to network. Tx TCP performs retransmission for reliable data transfer and management of transmit window and sequence number. Various test-cases are used to verify the TCP functions. The TCP Engine is synthesized using 0.18 micron technology and results in 51K gates not including buffers for temporal data storage.

• Journal of Korean Elementary Science Education
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• v.27 no.4
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• pp.356-370
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• 2008

The study aims to explore sequence of earth science content in elementary school science curriculum in Korea and the U.S.. The analysis is focused on a) general content structure of earth science part; b) concept relationship between grades in the specific field of 'geology'; c) longitudinal connection of concepts and content in 'geology.' The findings are as follows. First, earth science curriculum content in Korea is structured according to sub-scientific disciplines centering on not science concepts but topics or inquiry activities whereas the U.S. curricular content is organized through integrative earth science topics with basic concepts and sub-concepts. Second, it is a common feature that basic concepts are interrelated to sub-concepts in all grades in both countries. However, basic concepts are scattered all over the grades, presented in a linear pattern in Korea while those are provided together in 3rd grade and repeated with extended concepts in a spiral structure in the U.S.. Last, it is not clear how concepts and content are longitudinally connected between grades in Korean curriculum. On the contrary, concepts and content in the U.S. curriculum have a strong longitudinal connection between grades with conceptual hierarchy. Such results indicate that Korean elementary school science curriculum would limit students' comprehensive understanding of science concepts through grades. The study suggests Korean science content should strengthen interrelationship among concepts as well as longitudinal connection between grades, in order to achieve the ultimate goal of science education, 'scientific literacy'.

• Korean Journal of Mathematics
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• v.23 no.3
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• pp.371-377
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• 2015

In this note, we consider a generalized Fibonacci sequence {$q_n$}. Then give a connection between the sequence {$q_n$} and the Chebyshev polynomials of the second kind $U_n(x)$. With the aid of factorization of Chebyshev polynomials of the second kind $U_n(x)$, we derive the complex factorizations of the sequence {$q_n$}.

• International Journal of High-Rise Buildings
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• v.11 no.3
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• pp.189-196
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• 2022

The practical difficulties of construction will impose many restrictions on the structural design, and the construction method can also provide unexpected ideas for solving design problems. Through the discussion of three issues closely related to construction in the structural design of Wuhan Center, this paper illustrates the importance of in-depth consideration of the construction situations in the structural design stage. The topics of "Connection between Embedded Steel Plates in Steel Plate Composite Shear Wall" and "Connection Joint between Outrigger Truss and Core Wall" are about how to facilitate on-site construction by simplifying and optimizing detail design. The topic of "Adjusting Internal Force Distribution by Optimizing Construction Sequence" is about how to make the construction process a tool for structural design.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1241-1250
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• 2018

Parallel three-phase voltage source inverters in a direct connection configuration are widely used to increase system power ratings. A zero-sequence circulating current can be generated according to the switching method; however, the zero-sequence circulating current not only distorts current, but also reduces the system reliability and efficiency. In this paper, a model predictive control scheme is proposed for parallel inverters to drive an interior permanent magnet synchronous motor with zero-sequence circulating current suppression. The voltage vector of the parallel inverters is derived to predict and control the torque and stator flux components. In addition, the zero-sequence circulating current is suppressed by designing the cost function without an additional current sensor and high-impedance inductor. Simulation and experimental results are presented to verify the proposed control scheme.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.4
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• pp.169-174
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• 2002

The magnitude and phase of the compensating voltage in Dynamic Voltage Restorer (DVR) system depend on the voltage sag in the phases affected by the fault and on the influence of the zero sequence components. If the delta connection of the transformer is used, the zero sequence components do not appear on the load side. But nowadays, Y connected transformers with grounded neutral, that is 3-phase 4-wire system, are usually used. Therefore the zero-sequence components are occurred during faults. The zero-sequence components result in the high insulation costs and the asymmetry of the phase and magnitude of the terminal voltages. In this paper 3 phase 4 wire distribution system and 3 phase 3 wire system are analyzed and characteristics of voltage sag are presented. And this paper proposes the method that can mitigate the zero-sequence under the unbalance faults causing voltage sage and phase angle iumps.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.3
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• pp.155-163
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• 2007

In Ad Hoc Networks, a connection breaks due to the irregular movement of mobile nodes and the inherent characteristics of the wireless medium such as the interference and the multi-path fading. AODV, a typical on-demand routing protocol in Ad Hoc networks, uses Destination sequence numbering for loop-free, but it may cause RREQ broadcast storm problem. This paper proposes AODV_ods that does not need destination sequence number, in routing message and routing table without routing loop. To show the effectiveness of the proposed scheme, we performed extensive simulation with NS-2. The simulation results show that the proposed ADOV_ods efficiently uses wireless bandwidth compare to the original AODV. Finally AODV ods reduces the routing overhead, end to end delay and increases the overall packet delivery ratio.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.155-162
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• 2006

Space is integrated or segment with organic formation by circulation path. It estimates important problem to grasp as factor that promote movement of visitor and space organization without grasping circulation as connection relation about simple space function from these viewpoint, is a thing which this study does not cause confusion to visitor's circulation path through data that analyze form of space connection and visitor's circulation path as quantitative in museum space and layout form that access by easy each unit exhibition grasps what it is. This study does factor grasping for guideline and inspection circulation path of layout by purpose in exhibition space on the basis of analytical result that grasps connection form between exhibition area that grasp laying stress on visitor's movement and appears in space through follow-up survey for circulation path of museum exhibition area. Space connection form that is expose by sequence of investigation and analysis(II) estimates on constituent affecting to visitor's circulation, and these do not speak for all space connection forms at the museum, but may systematize typology about connection form of unit spaces to utilize by indicator pointer of space planning if continue study to various spatial sphere more than hereafter. Unit exhibition area, divide connection form of space by grid and tree and laying stress on this quantitative data by spectator follow-up survey comparison and Estimate that space connection form provides partial basis of judgement for supposition that can promote direction and circulation path about visitor's movement if summarize result of investigation and analysis (III).