• Communications for Statistical Applications and Methods
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• v.20 no.4
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• pp.301-309
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• 2013

This paper predicts gross box office revenue for domestic films using the Korean film data from 2008-2011. We use three regression methods, Linear Regression, Random Forest and Gradient Boosting to predict the gross box office revenue. We only consider domestic films with a revenue size of at least KRW 500 million; relevant explanatory variables are chosen by data visualization and variable selection techniques. The key idea of analyzing this data is to construct the meaningful explanatory variables from the data sources available to the public. Some variables must be categorized to conduct more effective analysis and clustering methods are applied to achieve this task. We choose the best model based on performance in the test set and important explanatory variables are discussed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.2
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• pp.103-109
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• 2001

In this paper, the prestressing order of tendons is studied to minimize a bursting force of an anchorage. The bursting forces is a primary factor of anchorage failures. The forces of the anchorage depend on the prestressing order and size of the tendons, if a lot of tendons are introduced to the anchorage. Many studies have been made to analyze the bursting force of the anchorage. However, the studies have been limited to the bursting forces of the anchorage having one or two tendons. PSC box girder bridges usually have a lot of tendons. And the difference of the bursting forces lies in the prestressing order of the tendons. As a result of the lack of studies on the prestressing order for the bridges, the order depends on the designer's intuition and experiences. It may be stated that this study should be useful for determining the reasonable prestressing order of tendons for the PSC box girder bridges.

• Structural Engineering and Mechanics
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• v.35 no.5
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• pp.539-554
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• 2010

Light weight superstructure is beneficial for bridges in remote areas and in emergency erection. In such weight sensitive applications, combination of fibre reinforced plastics (FRP) as material and box-girders as a structural system have great scope. This combination offers various options to tailor structure and its elements but this flexibility poses greater challenge in optimum design. In this paper a procedure is derived for a generalised optimum design of FRP box-girder bridges, using genetic algorithms (GA). The formulation of the optimum design problem in the form of objective function and constraints is presented. Size, configuration and topology optimization are done simultaneously. A few optimum design studies are carried out to check the performance of the developed procedure and to get trends in the optimum design which will be helpful to the new designers.

• Earthquakes and Structures
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• v.17 no.5
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• pp.521-532
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• 2019

This paper describes the construction of a laminar box for simulating the earthquake response of soil and structures. The confinement of soil in the transverse direction does not rely on the laminar frame but is instead achieved by two acrylic glass walls. These walls allow the behaviour of soil during an earthquake to be directly observed in future study. The laminar box was used to study the response of soil with structure-footing-soil interaction (SFSI). A single degree-of-freedom (SDOF) structure and a rigid structure, both free standing on the soil, were utilised. The total mass and footing size of the SDOF and rigid structures were the same. The results show that SFSI considering the SDOF structure can affect the soil surface movements and acceleration of the soil at different depths. The acceleration developed at the footing of the SDOF structure is also different from the surface acceleration of free-field soil.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.163-174
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• 2023

Though box compression strength (BCS) is commonly used as a performance criterion for shipping containers, estimating BCS remains a challenge. In this study, artificial neural networks (ANN) are implemented as a new tool, with a focus on building up ANN architectures for BCS estimation. An Artificial Neural Network (ANN) model can be constructed by adjusting four modeling factors: hidden neuron numbers, epochs, number of modeling cycles, and number of data points. The four factors interact with each other to influence model accuracy and can be optimized by minimizing model's Mean Squared Error (MSE). Using both data from the literature and "synthetic" data based on the McKee equation, we find that model estimation accuracy remains limited due to the uncertainty in both the input parameters and the ANN process itself. The population size to build an ANN model has been identified based on different data sets. This study provides a methodology guide for future research exploring the applicability of ANN to address problems and answer questions in the corrugated industry.

• Journal of the Korean GEO-environmental Society
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• v.12 no.8
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• pp.5-12
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• 2011

This study was performed to analyze the degree of rainfalls, the duration time of rainfalls, the inclination of slopes and other damage causes depending on the ground condition, when the landslide occurs by the rainfall. Based on that, a big and a small model soil box were compared to examine the features of landslides, which is ultimately for forecasting landslides. An artificial rainfall device was installed in the model box, and the large model box has a real-size slope in it. Also, various measures were fulfilled such as collapse forms, a pore pressure, an earth pressure and moisture contents in order to analyze the effect of the model box size on the landslide mechanism and to test the usability of a small model box as a material for landslide experiments.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.5
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• pp.751-763
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• 2022

With the recent increase in spending growth in the IoT sector worldwide, the importance of lightweight block ciphers to encrypt them is also increasing. The lightweight block cipher PIPO algorithm proposed in ICISC 2020 is an SPN-structured cipher using an unbalanced bridge structure. The white box attack model refers to a state in which an attacker may know the intermediate value of the encryption operation. As a technique to cope with this, Chow et al. proposed a white box implementation technique and applied it to DES and AES in 2002. In this paper, we propose a white box PIPO applying a white box implementation to a lightweight block cipher PIPO algorithm. In the white box PIPO, the size of the table decreased by about 5.8 times and the calculation time decreased by about 17 times compared to the white box AES proposed by Chow and others. In addition, white box PIPO was used for mobile security products, and experimental results for each test case according to the scope of application are presented.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.9
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• pp.710-715
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• 2016

Due to its simplicity and high reliability, the box-counting(BC) method is one of the most frequently used techniques to estimate the fractal dimensions of a binary image with a self-similarity property. The fractal calculation requires data sampling that determines the size of boxes to be sampled from the given image and directly affects the accuracy of the fractal dimension estimation. There are three non-overlapping regular grid methods: geometric-step method, arithmetic-step method and divisor-step method. These methods have some drawbacks when the image size M becomes large. This paper presents a BC algorithm for enhancing the accuracy of the fractal dimension estimation based on a new sampling method. Instead of using the geometric-step method, the new sampling method, called the coverage ratio-step method, selects the number of steps according to the coverage ratio. A set of experiments using well-known fractal images showed that the proposed method outperforms the existing BC method and the triangular BC method.

• Journal of Information Technology Applications and Management
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• v.18 no.1
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• pp.125-141
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• 2011

As the sales volume of online shops increases, the job burden in the back-offices of the online shops also increases. Order picking is the most labor-intensive operation among the jobs in a back-office and mid-size pure click online shops are experiencing the time delay and complexity in order picking nowadays while fulfilling their customers' orders. Those warehouses of the mid-size shops are based on manual systems, and as order pickings are repeated, the warehouses get a mess and lots of products in those warehouses are getting missing, which results in severe delay in order picking. To overcome this kind of problem in online clothing shops, we research a methodology to locate warehousing products. When products arrive at a warehouse, they are packed into a box and located on a rack in the warehouse. At this point, the operator should determine the box to be put in and the location on the rack for the box to be put on. This problem could be formulated as an Integer Programming model, but the branch-and bound algorithm to solve the IP model requires enormous computation, and sometimes it is even impossible to get a solution in a proper time. So, we relaxed the problem, developed a set of heuristics as a methodology to get a semi-optimum in an acceptable time, and proved by an experiment that the solutions by our methodology are satisfactory and acceptable by field managers.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.133-134
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• 2023

In general, all buildings are equipped with various types of handles for opening and closing the door, and unlike wooden doors, steel doors such as fire doors are equipped with a box-shaped door lock box frame surrounding the outside of the door lock to protect the door lock, which is called a cylinder protection cover. These cylinder protection covers have various types and types of fastening structures, and the cylinder protection covers on the market are molded in factories and standardized according to the size and shape of the door lock, requiring various types of cylinder protection covers. Accordingly, a variable cylinder protection cover with a simple prefabricated structure that can fundamentally solve these problems can be used as one cylinder protection cover regardless of the type, shape, and size of the door lock.