• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.13 no.2
• /
• pp.245-256
• /
• 2000

A moment-curvature relationship to simulate the behavior of reinforced concrete beam under cyclic loading is introduced. Unlike previous moment-curvature models and the layered section approach, the proposed model takes into consideration the bond-slip effect by using monotonic moment-curvature relationship constructed on the basis of the bond-slip relation and corresponding equilibrium equation at each nodal point. In addition, the use of curved unloading and reloading branches inferred from the stress-strain relation of steel gives more exact numerical result. The advantages of the proposed model, comparing to layered section approach, may be on the reduction in calculation time and memory space in case of its application to large structures. The modification of the moment-curvature relation to reflect the fixed-end rotation and pinching effect is also introduced. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed model.

• Journal of the Korea Society of Computer and Information
• /
• v.5 no.2
• /
• pp.30-36
• /
• 2000

The hidden node plays a role of the functional units that classifies the features of input pattern in the given question. Therefore, a neural network that consists of the number of a suitable optimum hidden node has be on the rise as a factor that has an important effect upon a result. However there is a problem that decides the number of hidden nodes based on back-propagation learning algorithm. If the number of hidden nodes is designated very small perfect learning is not done because the input pattern given cannot be classified enough. On the other hand, if designated a lot, overfitting occurs due to the unnecessary execution of operation and extravagance of memory point. So, the recognition rate is been law and the generality is fallen. Therefore, this paper suggests a method that decides the number of neural network node with feature information consisted of the parameter of learning algorithm. It excludes a node in the Pruning target, that has a maximum value among the feature value obtained and compares the average of the rest of hidden node feature value with the feature value of each hidden node, and then would like to improve the learning speed of neural network deciding the optimum structure of the multi-layer neural network as pruning the hidden node that has the feature value smaller than the average.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.30 no.5
• /
• pp.389-396
• /
• 2017

Peridynamics has been widely used in the dynamic fracture analysis of brittle materials. Recently, various crack patterns(compact region, floret, Hertz-type crack, etc.) of multilayered glass structures in experiments(Bless et al. 2010) were implemented with a bond-based peridynamic simulation(Bobaru et al.. 2012). The actual glass layers are bound with thin elastic interlayer material while the interlayer is missing from the peridynamic model used in the previous numerical study. In this study, the peridynamic interlayer modeling for the multilayered structures is proposed. It requires enormous computational time and memory to explicitly model very thin interlayer materials. Instead of explicit modeling, fictitious peridynamic particles are introduced for modeling interlayer materials. The computational efficiency and accuracy of the proposed peridynamic interlayer model are verified through numerical tests. Furthermore, preventing penetration scheme based on short-range interaction force is employed for the multilayered structure under compression and verified through parametric tests.

• Journal of Korean Society for Geospatial Information Science
• /
• v.18 no.4
• /
• pp.21-30
• /
• 2010

In this paper, the parallel distributed rainfall runoff model(K-DRUM) using MPI(Message Passing Interface) technique was developed to solve the problem of calculation time as it is one of the demerits of the distributed model for performing physical and complicated numerical calculations for large scale watersheds. The K-DRUM model which is based on GIS can simulate temporal and spatial distribution of surface flow and sub-surface flow during flood period, and input parameters of ASCII format as pre-process can be extracted using ArcView. The comparison studies were performed with various domain divisions in Namgang Dam watershed in case of typoon 'Ewiniar' at 2006. The numerical simulation using the cluster system was performed to check a parallelization effectiveness increasing the domain divisions from 1 to 25. As a result, the computer memory size reduced and the calculation time was decreased with increase of divided domains. And also, the tool was suggested in order to decreasing the discharge error on each domain connections. The result shows that the calculation and communication times in each domain have to repeats three times at each time steps in order to minimization of discharge error.

• The Journal of the Korea Contents Association
• /
• v.18 no.1
• /
• pp.289-304
• /
• 2018

The fandom phenomenon of political emotion originated from ideological conflicts between the conservative and the progressive amplifies social conflicts in South Korea in interpreting and accepting films as culture media. The purpose of this paper is to examine why the structure of political consciousness in South Korea is fandomized, what is the acceptance of cinema at the center of the controversy of political ideology, and what is the desirable attitude of film reception. I conducted a discourse analysis that closely examined the debates and articles on the internet regarding ,(2013) and ,(2014) which were controversial in terms of conservatism and progressivism. As a result, First, while Korean society has not constituted a consensus on modern and contemporary history, it has easily led the acceptance of cinema to the controversy surrounding the political ideology. Second, the failure of constructing consensual memories of modern and contemporary history has made the conservative and the progressive not acknowledge the other's achievements. Third, film interpretation and meaning production are ultimately the roles of the audience, and on interpretation, diversity should be respected but conformity would be rejected. Film acceptance and interpretation should focus on rational awareness of social reality and would reflect on the social ideal objectively.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.49 no.1
• /
• pp.19-30
• /
• 2012

For digital data compression, the quantization is the main part of the lossy source coding. In order to improve the performance of quantization, the vector quantizer(VQ) can be employed. The encoding complexity, however, exponentially increases as the vector dimension or bit rate gets large. Much research has been conducted to alleviate such problems of VQ. Especially for high bit rates, a constrained VQ, which is called the sample-adaptive product quantizer(SAPQ), has been proposed for reducing the hugh encoding complexity of regular VQs. SAPQ has very similar structure as to the product VQ(PQ). However, the quantizer performance can be better than the PQ case. Further, the encoding complexity and the memory requirement for the codebooks are lower than the regular full-search VQ case. Among SAPQs, 1-SAPQ has a simple quantizer structure, where each product codebook is symmetric with respect to the diagonal line in the underlying vector space. It is known that 1-SAPQ shows a good performance for i.i.d. sources. In this paper, a study on designing 1-SAPQ for the first-order Markov process. For an efficient design of 1-SAPQ, an algorithm for the initial codebook is proposed, and through the numerical analysis it is shown that 1-SAPQ shows better quantizer distortion than the VQ case, of which encoding complexity is similar to that of 1-SAPQ, and shows distortions, which are close to that of the DPCM(differential pulse coded modulation) scheme with the Lloyd-Max quantizer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.477-477
• /
• 2008

For more than three decades, the gate dielectrics in CMOS devices are $SiO_2$ because of its blocking properties of current in insulated gate FET channels. As the dimensions of feature size have been scaled down (width and the thickness is reduced down to 50 urn and 2 urn or less), gate leakage current is increased and reliability of $SiO_2$ is reduced. Many metal oxides such as $TiO_2$, $Ta_2O_4$, $SrTiO_3$, $Al_2O_3$, $HfO_2$ and $ZrO_2$ have been challenged for memory devices. These materials posses relatively high dielectric constant, but $HfO_2$ and $Al_2O_3$ did not provide sufficient advantages over $SiO_2$ or $Si_3N_4$ because of reaction with Si substrate. Recently, $HfO_2$ have been attracted attention because Hf forms the most stable oxide with the highest heat of formation. In addition, Hf can reduce the native oxide layer by creating $HfO_2$. However, new gate oxide candidates must satisfy a standard CMOS process. In order to fabricate high density memories with small feature size, the plasma etch process should be developed by well understanding and optimizing plasma behaviors. Therefore, it is necessary that the etch behavior of $HfO_2$ and plasma parameters are systematically investigated as functions of process parameters including gas mixing ratio, rf power, pressure and temperature to determine the mechanism of plasma induced damage. However, there is few studies on the the etch mechanism and the surface reactions in $BCl_3$ based plasma to etch $HfO_2$ thin films. In this work, the samples of $HfO_2$ were prepared on Si wafer with using atomic layer deposition. In our previous work, the maximum etch rate of $BCl_3$/Ar were obtained 20% $BCl_3$/ 80% Ar. Over 20% $BCl_3$ addition, the etch rate of $HfO_2$ decreased. The etching rate of $HfO_2$ and selectivity of $HfO_2$ to Si were investigated with using in inductively coupled plasma etching system (ICP) and $BCl_3/Cl_2$/Ar plasma. The change of volume densities of radical and atoms were monitored with using optical emission spectroscopy analysis (OES). The variations of components of etched surfaces for $HfO_2$ was investigated with using x-ray photo electron spectroscopy (XPS). In order to investigate the accumulation of etch by products during etch process, the exposed surface of $HfO_2$ in $BCl_3/Cl_2$/Ar plasma was compared with surface of as-doped $HfO_2$ and all the surfaces of samples were examined with field emission scanning electron microscopy and atomic force microscope (AFM).

• Korean Institute of Interior Design Journal
• /
• v.26 no.6
• /
• pp.210-221
• /
• 2017

First, we can define how our body perceives the external world and embodies its senses through the philosopher Merleau - Ponty. These philosophical orientations of Merleau-Ponty also appear to urban theorists such as Jane Jacobs, Gordon Cullen, and Juhani Pallasmaa. In other words, after the Second World War, people began to pay attention to human emotions and perceptions while opposing human rational thinking. Especially, they reject the abstract space of modernism and explore the everyday city space where the local character of the area lives. This place is a space where the collective memory of the group is shared over several generations. So, in this space, people's active perceptual system works actively. In the sense of this continuity of time, their ideas intersect with the concept of urban. Specifically, Jacobs criticizes massive development and proposes the development of a small block-based city with a commonality of old and new. In addition, we argue that urban space can be a visually interesting object through the continuous visual concept of urban theorist Cullen. In particular, he rediscovers the value of traditional urban space through visual experience between architecture and urban facilities. Finally, the architectural city theorist, Pallasmaa., criticizes the visual centrality of modern cities and thinks about the value of multidisciplinary space that can be experienced in architecture. This study examines the space of reproduction in detail on the perspective of the body philosophy and urban theorists. In other words, the play space inherits the natural city time, so when our body experiences this play space, we can actively sense and perceive the various senses. So we can invoke the active external actions of our bodies. Through the analysis of the size of the reconstruction space of the architectural city, various types of body senses and responses can be. Yoon Dongju Literary Museum, which renovated the old water tank of the city, can recognize the unfamiliar sense of body in everyday life through the traces and smells of water in the past and the restrained visuality. In addition, Seonyudo Park, which regenerates the waste water purification plant, can experience a phenomenal phenomenon through water space, old concrete and traces of steel. Finally, with the most recently played Seoul Road 7017 can experience interesting urban spaces in terms of a variety of plants, a human scale space creating movement, and a continuous visual.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.519-522
• /
• 2017

In this paper, we propose an algorithm for an alternative method using the clustering algorithm in a system that needs classification to extract individual user context information. In the conventional user classification system, the user has to input his own information. In this paper, we will research and develop a system applying a clustering algorithm which can extract user 's perceived information applying the improved algorithm for user management base. Generally, the algorithm that distinguishes users with the same data makes sure that recorded information matches the newly entered information, and then responds accordingly. However, it is troublesome to manually input information of the new user. Therefore, in this paper, we propose a method to distinguish users by using the clustering algorithm based on the analyzed data from the working memory in the accumulated system without directly inputting the user information. The study shows that the management method applied to the applied algorithm is more adaptive in environments where the number of people is different from that of the existing system (as a subjective observer test method).

• Journal of Environmental Health Sciences
• /
• v.35 no.6
• /
• pp.468-477
• /
• 2009

To evaluate the current indoor air quality condition of private academic facilities in Korea and investigate its association with subjective symptoms of student residing at the same academic facilities, air quality monitoring was carried out in total of 20 academic facilities located in Seoul, Daejon and Chungnam from the beginning of January to the end of April, 2009. To assess the air quality condition of academic facilities, 6 air pollutants with temperature and humidity were measured simultaneously inside and outside of academic facilities. The rate of exceeding the Indoor Air Quality (IAQ) guideline concentrations in 6 air pollutants were 5%, 85%, 15%, 5%, 10% and 30% for CO, $CO_2$, PM10, HCHO, TVOCs and TBC, respectively. A questionnaire on 16 subjective symptoms related to indoor air quality was given to 342 students who studied at the 20 academic facilities. The most frequent symptom of students was 'I feel easily tired or sleepy', and this was followed by 'I feel muscular pain or stiffness on shoulder, back and neck'. The association of net difference (subjective symptoms at the academic facility - subjective symptoms of the usual situation) with air pollutants was analyzed using spearman rank correlation. In logistic analysis using proportional odds method, the students whose indoor air concentration of HCHO was ${\geq}60{\mu}g/m^3$ hadsignificant odds of having more subjective symptoms of 'My eyes are dry or feel irritated or itching' (OR=5.026: CI=1.587-15.911), 'I feel easily tired or sleepy' (OR=2.956: CI=1.072-8.152), 'I lose my concentration and I feel my memory is falling' (OR=7.745: CI=1.938-30.955) and 'I feel dizzy' (OR=4.424: CI=1.292-15.149) than those of <$60{\mu}g/m^3$.