• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.16-25
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• 2000

The influence of four process parameters of soft nip calendering including calendering pressure, temperature, moisture content and nip residence time on bulk, smoothness and tensile strength of newsprints has been investigated. In addition, the effect of basis weights on calendering responses has been examined. Bulk of newsprints decreased and smoothness increased with the increase of the calendering pressure, temperature, moisture content of the sheets and nip residence time. Improvement in tensile strength was observed when low calendering pressure and high temperature of heat-ing roll were employed. Tensile strength of the newsprint, however, decreased abruptly when the calendering temperature and pressure increased above certain levels due to the rupture of sheet structure, which has been verified by SEM. SEM micrographs also showed that it would be possible to maintain the inner bulk while densifying the fibers on the outer surface of newsprint by adjusting the soft nip calendering variables properly.

• Journal of Industrial Technology
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• v.24 no.A
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• pp.23-28
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• 2004

Seat is one of the most important part of an automobile for passenger's safety especially when an accident happens. A recliner is a part of the seat assembly, having the function of adjusting the back-plate angle of a seat. Recently, many kinds of vehicles have adopted the round recliner module rather than the conventional types of recliners because of its broad compatibility and structural simplicity. In this study a two-dimensional finite element strength analysis has been performed using a commercial code ABAQUS/Standard for the purpose of developing a new round recliner model. The loading condition for the analysis is the same as the FMVSS 301 regulation. The finite element result for the round recliner has been compared with that for the conventional type.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1663-1668
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• 2010

The terms of track is a train-only line for a train service, in premises of station of a station, that the unit over the track for turnout the track from one track to another track, which it changes the course from the main track that is used for operating a train to the side track, is called a turnout The stick strength of tongue rail is adjusting uniform pressure on the both sides, the adhesion strength between a basic rail and tongue rail has to maintain over 100kg of power value to open over 1mm the ends. This study suggested developing a measuring instrument that can measure a basic rail and the stick strength of a movable rail in according with a switch, such as a switch point, and a performance test. This study ties to be helped that it improves measuring usability for the maintainers through improving quality in a stick measuring instrument, that it solves a technique in the site difficulties through improving a measuring instrument, with reducing the obstacles and expenses.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.309-312
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• 2004

The hydraulic structure of the hydroelectric power plant such as aqueduct tunnels and the drainage canal became old. Therefore, because the concrete surface of the aqueduct tunnel has received severe damage by wear-out and the crack etc the repair is demanded. This research examined the applicability of the repair mortar which mixed the fly ash and an artificial aggregate by using the very high early strength cement. As a result, good Quality repair mortar which satisfied the demand performance more than self-flow 270mm and compressive strength $50N/mm^2$ (age of 28days) adjusting of water cement ratio by using the MTX cement be able to be manufactured.

• KIEAE Journal
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• v.7 no.6
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• pp.119-126
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• 2007

In the field of composite structures, the use of carbon tube for the confinement of concrete has been arisen since 1990's. However, experimental and analytical studies were limited to those of reinforced concrete and concrete filled steel tube. The carbon tube provides excellent confinement capabilities for concrete cores, enhancing compressive strength and ductility of concrete significantly. The carbon tube has high tensile strength, light weight, corrosion immunity and high fatigue strength properties. Since carbon fiber is an anisotropic material, carbon tube could be optimized by adjusting the fiber orientation, thickness and the number of different layers. In this study, both experimental and analytical studies of axial and lateral behavior of full-scale CFCT (Concrete Filled Carbon Tube) columns subjected to monotonic axial load were carried out using Drucker-Prager theory. And, based on comparison results between experiment results and analytical results, k factor estimation was proposed for effective analysis.

• Journal of Drive and Control
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• v.19 no.3
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• pp.1-8
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• 2022

In this paper, the design of automatic impact force control mechanism of hydraulic breaker was studied. The control mechanism uses the change of piston upper chamber pressure, when the hydraulic breaker impacts various strength rock. The piston stroke is controlled by rock strength sensing valve, piston stroke switching valve, and piston control valve. It is imperative to denote the area of each valve section, the spring constant of the spring. It provides convenience to users by automatically adjusting the appropriate striking force, according to the strength of the rock. Additionally, by increasing work productivity, it can contribute to reducing greenhouse gas emissions due to fuel efficiency reduction.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.255-256
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• 2022

As part of a study to alleviate problems caused by cracks in concrete structures, this study compares and analyzes the fluidity and strength characteristics of mortars used by adjusting the mixing ratio of two types of PCC(Powder Compacted Capsule) manufactured by different methods.

• 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 Family Resource Management and Policy Review
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• v.17 no.3
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• pp.1-17
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• 2013

This study focused on adolescents who are studying in middle schools of the Gyeongnam region, aims to provide methods for improving school adjustment among adolescents through the enhancement of family strength. It will examine the effect of family strength on adolescents' school adjustment verify the mediating effect of social support in the influential relationships of school adjustment. The summarizations, obtained in this study are as follows: First, an analysis of the results of the effect of family strength on social support demonstrated that family strength had a positive effect on social support. That is, as family strength was higher, social support increased. Second, an analysis of the results of the effect of family strength on school adjustment show that family strength would have a direct effect on school adjustment, which is positive. Where family strength was higher, school adjustment of adolescents was also higher. Third, the results of the effect of social support on school adjustment when controlling family strength demonstrate that social support would have a positive effect on school adjustment, however, family strength did not predict school adjustment. Therefore, the complete mediating effect of social support in the relationship between family strength and school adjustment was identified. In conclusion, it was identified that family strength had an indirect effect on school adjustment, but not a direct effect. Therefore, it is indicated that indirect intervention through the social support system as well as direct intervention for the improvement of adolescents' school adjustment is required. In addition, it was confirmed that family strength and social support would be more important variables than control variables, which reflect the characteristics of adolescents and family in terms of school adjustment. Therefore, the recognition that the responsibility in adjusting to school is the common role of families, schools, and community going beyond the individual responsibility of adolescents is needed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.1
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• pp.59-65
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• 2017

A seat track product is a car seat part that provides a base for vehicle seats. An ultra-high strength steel sheet is used to reduce the weight of vehicle body parts. However, the formability of an ultra-high strength steel sheet is poor because of its very low elongation and very high elastic deformation. For this reason, a new forming technology of an ultra-high strength steel sheet is required. The influence of spring-back of seat track parts on the shape freeze in forming processes was investigated to be solved by adjusting the appropriate tool design such as minus clearance between punch and die, and punch angle. This paper describes how to apply the spring-back prevention technique for improving shape freeze by using the ultra-high strength steel sheet with 980MPa to develop lightweight seat tract parts.