• Nuclear Engineering and Technology
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• 제41권6호
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• pp.753-764
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• 2009

JAEA started the LSTF experiments in 1985 for the fourth stage of the ROSA Program (ROSA-IV) for the LWR thermal-hydraulic safety research to identify and investigate the thermal-hydraulic phenomena and to confirm the effectiveness of ECCS during small-break LOCAs and operational transients. The LSTF experiments are underway for the ROSA-V Program and the OECD/NEA ROSA Project that intends to resolve issues in thermal-hydraulic analyses relevant to LWR safety. Six types of the LSTF experiments have been done for both the system integral and separate-effect experiments among international members from 14 countries. Results of four experiments for the ROSA Project are briefly presented with analysis by a best-estimate (BE) code and a computational fluid dynamics (CFD) code to illustrate the capability of the LSTF and codes to simulate the thermal-hydraulic phenomena that may appear during SBLOCAs and transients. The thermal-hydraulic phenomena dealt with are coolant mixing and temperature stratification, water hammer up to high system pressure, natural circulation under high core power condition, and non-condensable gas effect during asymmetric SG depressurization as an AM action.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.799-804
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• 2001

Nonlinear normal mode (NNM) vibration, in a nonlinear dual mass Hamiltonian system, which has 6th order homogeneous polynomial as a nonlinear term, is studied in this paper. The existence, bifurcation, and the orbital stability of periodic motions are to be studied in the phase space. In order to find the analytic expression of the invariant curves in the Poincare Map, which is a mapping of a phase trajectory onto 2 dimensional surface in 4 dimensional phase space, Whittaker's Adelphic Integral, instead of the direct integration of the equations of motion or the Birkhotf-Gustavson (B-G) canonical transformation, is derived for small value of energy. It is revealed that the integral of motion by Adelphic Integral is essentially consistent with the one obtained from the B-G transformation method. The resulting expression of the invariant curves can be used for analyzing the behavior of NNM vibration in the Poincare Map.

• 한국식품영양학회지
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• 제12권4호
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• pp.387-396
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• 1999

Dog meat was begun to be edible by the Chinese, Japanese, the French, Belginan, German Philippines Vietnamese, North-Americans African-Indians Canadian-aborigines Alaskan aborigines including Kor-eans. According to the record, Korea has a long history to have eaten dog meat from the era of Sam-kug(three kingdoms BC 57∼AC 668) and so there are numerous languages proverbs, and customs re-lated to the dog meat. Over the long history there have been many records and recipes about the edib-leness of dog meat. But at present time only the way of cooking such as Bosintang(a soup) Suyuk(a boiled meat) Duruchighi(boiled meat added spice and slightly roasted) Muchim(boiled meat added by spice and mixed) Gaesoju(an extract) Jeongol(boiled meat mixed with spices vegetables and water on the pot) remains. Koreans eat dog meat following the traditional customs n the Boknal(hottest day in summer). Also the areas of Buyo. Sochon, Boryong adn Chongyang of Chungnam province and the ad-jacent areas like Kongju, Iksan, and Nonsan have customs to kill the dog and offer dog meat to the gue-sts in time of small or big occasions such as funeral ceremony Hoigap(anniversary of one's 60th birth-day) and one's birthday. This range of customs is expanding larger and larger. These areas are the cen-ter of past Baekche(BC 57∼AC 660). In spite of this it is unreasonable, and excessive action for foreig-ner to fine fault with the dog meat or Korean food culture.

• 품질경영학회지
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• 제47권3호
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• pp.417-424
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• 2019

Purpose: In this study, the goal is to analyze this case to prevent the same accidents when using one-shot rifle. Methods: Detailed analysis of damaged parts must first be made in order to determine the cause of the abnormal explosion. The cause of abnormal operation can be determined by analyzing the information of damaged components and the firing mechanism of the weapon step by step. Also we can refer to a statement of shooter, witness and accident scene situation. Based on this theory, cause of abnormal firing can be narrow down. Results: Fracture of pin for fixing firing and latch is cause of abnormal operation of firing. Conclusion: It is deemed that periodic inspection and fundamental improvement of the structure are required to prevent the same accident as this.

• 한국멀티미디어학회논문지
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• 제22권10호
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• pp.1199-1207
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• 2019

Video surveillance data, which is used for preemptive or post-emptive action against any event or accident, is required for monitoring the location, but is reducing the capacity of the image data by removing intervals for cost reduction and system persistence. Such a video surveillance system is fixed in a certain position and monitors the area only within a limited angle, or monitors only the fixed area without changing the angle. At this time, the video surveillance system that is monitored only within a limited angle shows that the variation object such as the floating population shows different status in the image, and the background of the image maintains a generally constant appearance. The static objects in the image do not need to be stored in all the images, unlike the dynamic objects that must be continuously shot, and occupy a storage space other than the necessary ones. In this paper, we propose a mechanism to analyze the image, store only the small size image for the fixed background, and store it as image data only for variable objects.

• Earthquakes and Structures
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• 제9권2호
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• pp.281-303
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• 2015

The effects of infill panels on the response of r.c. frames subjected to seismic action are widely recognized. Numerous experimental investigations were effected and several analytical models were developed on this subject. This work, which is part of a larger project dealing with specific materials and structures commonly used in Italy, discusses experimental tests on masonry and samples of bare and infilled portals. The experimental activity includes tests on elemental materials, and 12 wall samples. Finally, three one-bay one-story reinforced concrete frames, designed according to the outdated Italian technical code D.M. 1996 without seismic details, were tested (bare and infilled) under constant vertical and cyclic lateral load. The first cracks observed on the framed walls occurred at a drift of about 0.3%, reaching its maximum capacity at a drift of 0.5% while retaining its capacity up to a drift of 0.6%. Infill contributed to both the stiffness and strength of the bare reinforced concrete frame at small drifts thus improving overall system behavior. In addition to the experimental activities, previously mentioned, the recalibration of a model proposed by Comberscue (1996) was evaluated. The accuracy of an OpenSees non linear fiber based model of the prototype tested, including a strut element was verified through a comparison with the final experimental results. This work has been partially supported by research grant DPC-ReLUIS 2014.

• Steel and Composite Structures
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• 제23권4호
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• pp.385-397
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• 2017

Currently, CFRP (Carbon Fiber Reinforced Polymer) plate bonding is used quite extensively as a strengthening method. In this technique, a composite CFRP plate or sheet of relatively small thickness is bonded with an adhesion material to steel or concrete structure in order to improve its structural behavior and strength. The sheets or plates do not require much space and give a composite action between the adherents. In this study, the rotation capacity of CFRP-strengthened cold-formed steel (CFS) beams has been evaluated through numerical investigation. Studies on different structural levels have been performed. At the beam level, C-section has been adopted with different values of profile thickness, web height, and flange width. At the connection level, a web bolted moment resistant type of connection using through plate has been adopted. In web-bolted connections without CFRP strengthening, premature web buckling results in early loss of strength. Hence, CFRP sheets and plates with different mechanical properties and geometric configurations have been examined to delay web and flange buckling and to produce relatively high moment strength and rotation capacity. The numerical results reveal that CFRP strengthening may increase strength, initial stiffness, and rotation capacity when compared with the case without strengthening.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.2866-2877
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• 2021

The complex coupling relationship between liquid sodium and concrete materials affects both the sodium fire characteristics and concrete properties through heat and chemical erosion. In this study, experiments on direct and indirect (separated by a steel plate) contact of the columnar sodium fire with the concrete surface were performed. It was found that the combustion efficiency of liquid sodium in direct contact with concrete was significantly enhanced and accompanied by intermittent explosions and splashing of small concrete fragments. The sodium fire on the surface of the concrete considerably increased the internal temperature, pore size, and distribution density of the concrete. In addition, the depth of influence on the loosening of the concrete structure was also greatly extended. The contact of liquid sodium with the concrete substantially affected its permeability resistance. The water absorption of the concrete surface was increased by more than 70% when liquid sodium directly impacted the bare concrete surface. However, the change in water absorption in the centre of the concrete was primarily affected by the duration of the external heat.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권8호
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• pp.2993-3010
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• 2021

The job shop scheduling problem (JSSP) plays a critical role in smart manufacturing, an effective JSSP scheduler could save time cost and increase productivity. Conventional methods are very time-consumption and cannot deal with complicated JSSP instances as it uses one optimal algorithm to solve JSSP. This paper proposes an effective scheduler based on deep learning technology named self-supervised long-short term memory (SS-LSTM) to handle complex JSSP accurately. First, using the optimal method to generate sufficient training samples in small-scale JSSP. SS-LSTM is then applied to extract rich feature representations from generated training samples and decide the next action. In the proposed SS-LSTM, two channels are employed to reflect the full production statues. Specifically, the detailed-level channel records 18 detailed product information while the system-level channel reflects the type of whole system states identified by the k-means algorithm. Moreover, adopting a self-supervised mechanism with LSTM autoencoder to keep high feature extraction capacity simultaneously ensuring the reliable feature representative ability. The authors implemented, trained, and compared the proposed method with the other leading learning-based methods on some complicated JSSP instances. The experimental results have confirmed the effectiveness and priority of the proposed method for solving complex JSSP instances in terms of make-span.

• Structural Engineering and Mechanics
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• 제69권6호
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• pp.677-691
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• 2019

In recent years, interest is growing in the engineering community on the experimental assessment and the theoretical prediction of the out-of-plane (OOP) seismic response of unreinforced masonry (URM) infills, which are widespread in Reinforced Concrete (RC) buildings in Europe and in the Mediterranean area. In the literature, some mechanical-based models for the prediction of the entire OOP force-displacement response have been formulated and proposed. However, the small number of experimental tests currently available has not allowed, up to current times, a robust and reliable evaluation of the predictive capacity of such response models. To enrich the currently available experimental database, six pure OOP tests on URM infills in RC frames were carried out at the Department of Structures for Engineering and Architecture of the University of Naples Federico II. Test specimens were built with the same materials and were different only for the thickness of the infill walls and for the number of their edges mortared to the confining elements of the RC frames. In this paper, the results of these experimental tests are briefly recalled. The main aim of this study is comparing the experimental response of test specimens with the prediction of mechanical models presented in the literature, in order to assess their effectiveness and contribute to the definition of a robust and reliable model for the evaluation of the OOP seismic response of URM infill walls.