• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11C
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• pp.1098-1105
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• 2009

In this paper, we propose an asynchronous UWB (Ultra Wide Band) Positioning scheme that can provide precise positioning performance with low complexity and low power consumption. We also present the residual test to improve the positioning performance in multipath channels having heavy NLoS (Non-Line of Sight) components. As compared to conventional ToA (Time of Arrival) positioning scheme that requires round-trip transmissions as many as the number of beacons, the proposed UWB positioning scheme effectively decrease power consumption and processing delay since a single round-trip transmission is only required. Also, as compared to conventional TDoA (Time Difference of Arrival) positioning scheme requiring precise synchronization among the beacons, asynchronous nature of the proposed scheme achieves very low system complexity. Through simulations in LoS (Line of Sight) channel models, we observe that the proposed scheme requires low system complexity, low power consumption, while providing positioning performance of almost the same accuracy as the conventional ToA and TDoA positioning schemes. In addition, the proposed scheme by employing the residual test achieves accurate positioning performance even in multipath channels having heavy NLoS components.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.35-47
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• 2020

Box-office prediction is important to movie stakeholders. It is necessary to accurately predict box-office and select important variables. In this paper, we propose a multivariate time series classification and important variable selection method to improve accuracy of predicting the box-office. As a research method, we collected daily data from KOBIS and NAVER for South Korean movies, selected important variables using Random Forest and predicted multivariate time series using Deep Learning. Based on the Korean screen quota system, Deep Learning was used to compare the accuracy of box-office predictions on the 73^rd day from movie release with the important variables and entire variables, and the results was tested whether they are statistically significant. As a Deep Learning model, Multi-Layer Perceptron, Fully Convolutional Neural Networks, and Residual Network were used. Among the Deep Learning models, the model using important variables and Residual Network had the highest prediction accuracy at 93%.

• Journal of the Korean GEO-environmental Society
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• v.15 no.8
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• pp.13-21
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• 2014

The Plastic Board Drain is used to improve soft soils deposited in container terminal area at a port. This paper describes settlement behavior of soft ground in this area from PBD installation to the time of operating facilities. Previous researches focused on soil improvement effect of PBD, that is, the settlement occurred during ground improvement period. The residual settlement occurred during operating the facility is very important from the maintenance and management point of view. However, the study of this residual settlement has been rarely conducted. In this study, by analyzing the measured settlement data obtained from the container terminal area at the port, it was verified that the residual settlement induced during operating facilities occurred in a layer with PBD improvement. In addition, by comparison the settlement predicted by a numerical analysis with the settlement measured in the field, it was confirmed that the actual settlement is in the range of predicted settlement.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.1
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• pp.79-83
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• 2010

The conventional welding technique such as shield metal arc welding has been mostly applied to the piping system of the nuclear power plants. It is well known that this welding technique causes the overheating and welding defects due to the large groove angle of weld. On the other hand, the narrow gap welding(NGW) technique has many merits, for instance, the reduction of welding time, the shrinkage of weld and the small deformation of the weld due to the small groove angle and welding bead width comparing with the conventional welds. These characteristics of NGW affect the deformation behavior and the distribution of welding residual stress of NGW, thus it is believed that the residual stress results obtained from conventional welding procedure may not be applied to structural integrity evaluation of NGW. In this paper, the welding residual stress of NGW was predicted using the nonlinear finite element analysis to simulate the thermal and mechanical effects of the NGW. The present results can be used as the important information to perform the flaw evaluation and to improve the weld procedure of NGW.

• Journal of Food Hygiene and Safety
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• v.9 no.1
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• pp.1-13
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• 1994

A Simultaneous determination method was improved for the determination and confirmation of zeranol, zearalenone, as well as their isomers and metabolites, in beef. The analytes were extracted from tissue by CH3CN, hydrolyzed enzymatically(for glucuronide conjugates), cleaned up by a strong basic anion exchange resin combined with a liquid/liquid partitioning, derivatized using MSTFA and confirmed, quantified by GC/MS/SIM with a internal standard, zearalane. The results were as follows : (1) all the estrogens were separated on the GC/MS chromatogram under the extraction method and the chromatographic conditions improved, the retention times of zearalane-TMS2, zearalanone-TMS2, zearalenone-TMS2, zeranol-TMS3, taleranol-TMS3, and $\alpha$-zearalenol-TMS3, $\beta$-zearalenol-TMS3, were 18.49, 19.44, 19.63, 19.71, 19.79 and 19.99, 20.08 minutes, respectively. (2) The calibration curves of residual zeranol, zearalenone and their metabolites showed constantly linear(r=0.99) in the range of 5~20 ng. The minimum detection concentration of residual zeranol, zearalenone and their metabolites was 1 ppb. (3) The total average recovery of residual zeranol, zearalenone and their metabolites from spiked beef was 60.2%(CV=29.7%) at the 1 ppb and 63.5%(CV=26.5) at the 2 ppb, 72.9%(CV=18.2%) at the 4 ppb. (4) The preservation method for 6 estrogens was improved for the fast running time(21 min) and MSTFA was utilized for derivatizing 6 estrogens for improvement of recovery, for good resolution, for characteristic mass spectra unlike Jose's method and Tina's method. The utilization of zearalane as internal standard showed good quantification result for zeranol, zearalenone, as well as their isomers and metabolites, in beef.

• Journal of the Korean Wood Science and Technology
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• v.12 no.2
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• pp.10-19
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• 1984

The $3{\times}3{\times}30$ ($cm^3$) sized lumbers of Populus alba-grandulosa L. were treated with four fire-retardant solutions of ammonium sulfate, monoammonium phosphate, diammonium phosphate and aluminium chloride for 1, 15, 30, and 60 minutes and 1, 3, and 7 days. Thereafter they were air-dried and burned at high temperature about $1,800^{\circ}C$ and for short time of five minutes. This study estimated the relationship between absorbed chemical amounts and rate of weight loss or residual bending strength of these burned lumbers. The results were as follows: 1) In absorption amount of fire-retardant chemicals, diammonium phosphate showed the largest, aluminium chloride the smallest, but monoammonium phosphate and ammonium sulfate showed similar level. 2) The absorption amount of chemicals was decreased with the increase of specific gravity in the same species except aluminium chloride. 3) The rate of weight loss was decreased as the absorption amount of chemicals increased, especially monoammonium phosphate was most effective. 4) The MOR value of the residual bending strength was increased as the absorption amount of chemicals increased and especially monoammonium phosphate showed the most efficient effect. 5) Aluminium chloride showed more striking increase of MOR value of residual bending strength with the increase of absorption amount than any other chemical, therefore its MOR value was similar to the maximum MOR value of the most effective monoammonium phosphate. 6) The correlation between weight loss and MOR value of the residual bending strength was negative and aluminium chloride showed the most striking negative relation, but the others showed similar trends. 7) The correlation between work to proportional limit and absorption amount of chemicals was positive and the degree of increase in work to proportional limit was most in aluminium chloride, and the next, in monoammonium phosphate and diammonium phosphate in turn. 8) The correlation between work to maximum load and absorption amount of chemicals showed positive and diammonium phosphate revealed the best result and aluminium chloride showed better results than other two chemicals.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.1-7
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• 2008

A study of new materials that are light-weight, high in strength has become vital to the machinery of auto industries. But then, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on by adopting residual stress. And Influence of corrosive condition for corrosion fatigue crack was investigated, after immersing in 3.5%NaCl, $10%HNO_3$+3.5%HF, $6%FeCl_3$. The immersion period was performed for 365days. The compressive residual stress was imposed on the surface according to each shot velocity based on shot peening, which is the method of improving fatigue life and strength. Fatigue life shows more improvement in the shot peened material than in the un peened material in corrosion conditions. The threshold stress intensity factor range was decreased in corrosion environments over ambient. Compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation. The fatigue crack growth rate of the Shot-peened material was lower than that of the un peened material. Also m, fatigue crack growth exponent and number of cycle of the shot peened material was higher than that of the un peened material. That is concluded from effect of da/dN.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.2
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• pp.114-125
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• 2020

In order to understand the currents around Hampyung Bay and Haeje Peninsula, 2D numerical simulations for tidal currents and tide-induced residual currents were carried out. Dominant semidiurnal tidal currents have reversing form and flow NNE-SSW from northern Haeje Peninsula to Songi Island, E-S at northern Haeje Peninsula and NNW-SSE in Hampyung Bay. In flood, a part of currents from Imja Island~Nakwhol Island flow along the main stream flowing northeast at offshore region and the rest flow into Hampyung Bay flowing east along the northern coast of Haeje Peninsula. In ebb, currents from Hampyung Bay flow west along the northern coast of Haeje Peninsula and run together with the main stream flowing southeast at offshore region. The currents create an anticyclonic circulation in flood and a cyclonic circulation in ebb around Haeje Peninsula including Hampyung Bay. Tidal currents are accumulated on Doripo which located at the entrance of Hampyung Bay and show high current velocities. Tidal currents and tide induced residual currents are weak at the inside of Hampyung Bay which has narrow entrance, shallow water depth and wide intertidal zone. An anticyclonic eddy is formed around Gaksi Island as a result of tide induced residual currents. In northern coast of Haeje Peninsula, slow constant currents flow east. It is expected that a gradual change of sediment and an increase of flushing time for suspended materials are carried by tidal currents occurring in Hampyung Bay.

• Food Science and Preservation
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• v.10 no.2
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• pp.236-240
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• 2003

This study was carried out to obtain fundamental data when developing new colostrum component fortified milk products. Residual immunoglobulin G (IgG) activities of both IgG fortified milk products under different pasteurization conditions and colostrum fortified milk powder products under different dissolving temperatures were measured. In the study, residual IgG activities of raw milk and IgG (50 mg and 250 mg) fortified milk products were sharply reduced upon increasing the temperature of heat treatment. After the low temperature long time (LTLT) treatment residual IgG activities of raw milk, IgG 50 mg and 250 mg fortified milk products decreased to 79%, 30％ and 21.6%, as compared to those before heat treatment respectively. However, almost no residual IgG activities were detected when IgG fortified milk was heated at 95$^{\circ}C$ for 15 sec. There was no significant change in the residual IgG activities of IgG fortified milk powder products upon different dissolving temperatures (30$^{\circ}C$, 40$^{\circ}C$, 50$^{\circ}C$ and 60$^{\circ}C$).

• Geophysics and Geophysical Exploration
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• v.22 no.2
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• pp.80-87
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• 2019

In this paper, we propose a method to apply the polynomial fitting for regional-residual separation of microgravity data based on the characteristics of gravity anomaly without a prior information. Since the microgravity survey is usually carried out in small regions, it is common to approximate regional anomaly by the first-order polynomial plane. However, if the regional anomaly patterns are difficult to be approximated to a first-order plane, the complete gravity anomaly is divided into small zones enough to approximate first-order plane by means of Parasnis density estimation method. The regional-residual separation is then applied on the splitted zones individually. When the gravity anomalies can be splitted spatially, we showed that the residual anomalies can be more effectively extracted based on the regional geological structures by regional anomaly separation from each of the divided regions, rather than applying the entire data set at one time.