• Journal of computational fluids engineering
• /
• v.13 no.3
• /
• pp.14-20
• /
• 2008

In this investigation, flow patterns past two identical nearby spheres at Re=300 were numerically studied. We considered all possible arrangements of the two spheres in terms of the distance between the spheres and, the angle inclined with respect to the main flow direction. It turns out that significant changes in shedding characteristics are noticed depending on how the two spheres are positioned. Collecting all the numerical results obtained, we propose a diagram for flow pattern on the distance vs. angle plane. The perfect geometrical symmetry implied in the flow configuration allows one to use that diagram to identify flow patterns past two identical spheres arbitrarily positioned in physical space with respect to the main flow direction.

• The Korean Journal of Applied Statistics
• /
• v.29 no.4
• /
• pp.581-594
• /
• 2016

We introduce innovations state space exponential smoothing models (ISS-ESM) that can analyze time series with multiple seasonal patterns. Especially, in order to control complex structure existing in the multiple patterns, the model equations use a matrix consisting of seasonal updating parameters. It enables us to group the seasonal parameters according to their similarity. Because of the grouped parameters, we can accomplish the principle of parsimony. Further, the ISS-ESM can potentially accommodate any number of multiple seasonal patterns. The models are applied to predict electricity demand in Korea that is observed on hourly basis, and we compare their performance with that of the traditional exponential smoothing methods. It is observed that the ISS-ESM are superior to the traditional methods in terms of the prediction and the interpretability of seasonal patterns.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.10
• /
• pp.185-193
• /
• 2022

This study attempted to compare and analyze the commercially available multi-use patterns to develop mask patterns suitable for the face types of adult women. Through this, it was intended to provide necessary data to mask pattern development and products. As a results of comparing the dimensions and shapes of commercial multi-use mask patterns, there was a significant difference in dimensions even though it was a L-size mask manufactured for adults. As a result of the appearance evaluation of the virtual outfit, there were significant differences by design in the vertical of the center front line, the cover and space of the mask, the height of the nose, and the lower part of the mask. The side also showed significant differences in the covering of the side of the face, the space of the side, and the width and length of the string. As a result of the appearance evaluation, Mask 4 received the best evaluation. The shape of the mask pattern had a large dart in the lower part of the nose so that it can cover the three-dimensional shape of the face, but there was a difference in the degree and angle of the curve depending on the mask. Although the upper part of the mask, the lower part of the mask, and the cheek part are in close contact, the evaluation of the mask pattern, which has room in the nose and mouth, was high. It is thought that the mask pattern should be set according to the upper length, lower length, and nose height of the mask through analysis of the face shape and dimensions.

• The Journal of the Korea Contents Association
• /
• v.19 no.9
• /
• pp.280-292
• /
• 2019

This study was carried out for the Centum Shinsegae Department Store, to grasp the indoor rest space and furniture design status, this study analyzes the characteristics of visitors' use behavior centered on furniture. The purpose of this study is to provide basic data for commercial rest space design by understanding the characteristics of resting space in commercial space and whether the furniture can support the behavior of visitors. The research method is to carry out on-site inspection, including the location of the rest space on each floor, the type and design characteristics of the furniture design, and the characteristics and patterns of the users on each were analyzed. The results of the study are as follows. As a result of analyzing the rest space and furniture, the furniture is brown, it has been provided with various designs such as fan-shaped, arched bench, sofa, chair type, and comfortable colors of lightness ranging from light gray to black, and appropriately supported the most common usage patterns.However, in the case of Shinsegae Department Store, it is necessary to consider the safety and convenience of the vulnerable groups.

• Architectural research
• /
• v.14 no.2
• /
• pp.45-56
• /
• 2012

The high rate of urban crime is a main issue that needs to be dealt with in this high-tech society. With the rapid increase of urban crime, research has mainly focused on topics either on a global or a local scale, such as cities or communities and houses or buildings, without reliable observational data. This study makes the best use of the nationwide surveys carried out by Korean government agencies for the analysis of urban crime patterns and factors in major Korean cities. The aims of this research are threefold: understanding the relationship between urban crime patterns and socio-economic differences in cities, determining the effect of residence types on the urban crime patterns; and uncovering potential influential factors of a crime victim's individual characteristics. The statistical methods used for the analysis of social statistical data are as follows: simple regression, logistic regression, one-way ANOVA and post-hoc test. This research found that the patterns of urban crime rate in cities have a certain tendency toward the cities' socio-economic and geographical differences. The residence type is an influential factor showing a close relation to the crime rate. Personal issues, such as the types of occupation, education, marriage, etc., are directly relevant to victims of crime.

• Journal of the Economic Geographical Society of Korea
• /
• v.15 no.1
• /
• pp.26-41
• /
• 2012

This study investigates the time-space characteristics of intra-urban passenger flows in the Metropolitan Seoul area. In particular, we analyze the relationships between transit ridership and land use through the use of the subway passenger flow data obtained from the transit transaction databases. For this purpose, the strength of each subway station, i.e., the number of total in-coming and out-going passengers at each station, in the morning, afternoon, and evening, is calculated and visualized, which reflects urban land use patterns. Then the subway stations are classified into four groups via a hierarchical analysis of the in-coming and out-going passenger flows at 353 stations. Each group appears to have characteristic properties according to the region, e.g., residential areas and central business districts. This has been confirmed by the analysis which probes explicitly the relationship between the local socio-economic variables and station groups. This analysis, disclosing the inter-relationship between the subway network and urban land use, may be useful at various stages in urban as well as transportation planning, and provides analytical tools for a wide spectrum of applications ranging from impact evaluation to decision-making and planning support.

• Journal of Korean Library and Information Science Society
• /
• v.36 no.4
• /
• pp.177-198
• /
• 2005

The objective of this paper is to obtain the knowledge for spatial Planning of children's library which serves various users. The study method is to observes the children and their parents' space use according to the age step of children in public library, and analyzes it in the relation with the classified 4-types of children's section. Five characteristics were identified. First, children area was influenced by library location and user's characteristics. Second, children area was used various aged group with children. Third, there were different use patterns based upon age. Fourth, various reading space was needed through areas. And, last the behavior and the characteristics of area and furnishings were described.

• Journal of the Korean housing association
• /
• v.27 no.6
• /
• pp.105-112
• /
• 2016

Although smart homes have been much developed in China, smart homes has been mainly towards the adoption of new technologies. There is little development of smart homes to consider and meet residents' needs in China. This study investigated residents' living in apartments in China using a questionnaire to identify their demands on smart homes. Through the survey, this study analyzed residents' space use patterns, daily living patterns etc. according to their ages. The results implied that there are significant differences in the use of spaces and demands on daily living within apartments. The results of this study should be considered for the development of smart homes in future. For example, it might be easier for people in the 20's to adopt Internet of Things (IoT) and environmental control systems compared to other age groups because most of them in the 20's use smart phones effectively without difficulties. In case of people in their 50's who stay home more times for taking a rest and eating meals compared to other age groups, smart technologies should be applied to support their health care and works in housings. This research emphasizing residents' experiences could be basis for the development of smart homes in China.

• Nuclear Engineering and Technology
• /
• v.25 no.2
• /
• pp.193-203
• /
• 1993

A new heuristic method for loading pattern search has been developed to overcome short-comings of the algorithmic approach. To reduce the size of vast solution space, general shuffling rules, a regionwise shuffling method, and a pattern grouping method were introduced. The entropy theory was applied to classify possible loading patterns into groups with similarity between them. The pattern search program was implemented with use of the PROLOG language. A two-group nodal code MEDIUM-2D was used for analysis of power distribution in the core. The above mentioned methodology has been tested to show effectiveness in reducing of solution space down to a few hundred pattern groups. Burnable poison rods were then arranged in each pattern group in accordance with burnable poison distribution rules, which led to further reduction of the solution space to several scores of acceptable pattern groups. The method of maximizing cycle length(MCL) and minimizing power-peaking factor(MPF) were applied to search for specific useful loading patterns from the acceptable pattern groups. Thus, several specific loading patterns that have low power-peaking factor and large cycle length were successfully searched from the selected pattern groups.

• Smart Media Journal
• /
• v.10 no.3
• /
• pp.9-22
• /
• 2021

Basically, machine learning models use input data to produce results. Sometimes, the input data is too complicated for the models to learn useful patterns. Therefore, feature engineering is a crucial data preprocessing step for constructing a proper feature set to improve the performance of such models. One of the most efficient methods for automating feature engineering is the autoencoder, which transforms the data from its original space into a latent space. However certain factors, including the datasets, the machine learning models, and the number of dimensions of the latent space (denoted by k), should be carefully considered when using the autoencoder. In this study, we design a framework to compare two data preprocessing approaches: with and without autoencoder and to observe the impact of these factors on autoencoder. We then conduct experiments using autoencoders with classifiers on popular datasets. The empirical results provide a perspective regarding the best suited autoencoder for these factors.