• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.469-470
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• 2008

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2907-2909
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• 2000

This paper proposes a force reflecting and compliant control scheme for the heavy-duty power manipulators with high ratio gear reducers at its joints. From the experimental results. it can be seen that the proposed scheme has an excellent compliant force control performance.

• The KSFM Journal of Fluid Machinery
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• v.17 no.4
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• pp.70-75
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• 2014

In this paper a analysis method is presented to obtain the steady state dynamic response from the finite element based equations of a rotor-bearing system with initial deflection. The method has been applied to analyze the dynamic response of the two-shaft rotor-bearing system with rigid coupling offset in a heavy duty gas turbine-generator. Bumps in the dynamic response of each rotor system have been observed at each critical speed due to the effect of initial deflection for rigid coupling offset. And, the dynamic responses have been shown to reduce for operating condition changes from cold to hot.

• Fashion & Textile Research Journal
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• v.9 no.6
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• pp.671-678
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• 2007

Formulations of compact and supercompact heavy-duty detergents, which are being used widely around the world, differ from those of conventional heavy-duty detergents. Significant differences in composition exist between the compact detergents and the conventional detergents. The compact detergents have a higher content of surfactants, oxygen bleach and enzymes than the conventional detergents. We have studied to find the most effective washing conditions of artificially soiled cloths with a commercial, supercompact, heavy-duty detergent and a drum type washing machine which is becoming the preferred type in Korea. Moreover, we have studied the washing performance with an impeller type washing machine, which has heretofore been the most popular type in East Asia. With the drum-type washing machine, washing performances improved as the washing temperatures went up and the washing times were lengthened. Though the rate of soil removal with a double recommended dosage was higher than with the recommended amount at $20^{\circ}C$, the effects of the higher dosage decreased as the washing temperatures increased. Finally, the washing performances with the two different dosages were the same at $60^{\circ}C$. The washing performances at $40^{\circ}C$ with the recommended dosage for 90 minutes were the same as with the double recommended dosage for 45 minutes. The soil removal efficiencies with the impeller-type washing machine were much lower than those of the drum-type washing machine. The reasons for this were the higher bath ratio that led to the lower concentration of wash liquor, the shorter washing time, and the lower washing temperature.

• Journal of the Korean Institute of Gas
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• v.15 no.1
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• pp.9-14
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• 2011

Heavy duty diesel engine has relatively small portion of whole vehicles due to long drive distance and large engine displacement, but largely influences atmosphere environment. City buses changed to CNG (Compressed Natural Gas) bus with Korea-Japan Worldcup. Heavy duty truck and intercity bus, however, were impossible to use CNG because those kinds of vehicles had long drive distance and CNG station was installed mainly at the around of the bus garage of city. Insulation container storing the natural gas as a liquid makes heavy duty truck and intercity bus possible to use the natural gas. Drive using diesel is possible where is hard to recharge the gas. With LNG (Liquefied Natural Gas), the dependence on oil is largely decreased, PM (Particulate Matter) and NOx which is chronic disadvantage of diesel is remarkably reduced and finally $CO_2$, the representative green house gas, is reduced over 10%.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.3
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• pp.73-82
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• 2011

Most of countries start to restrict the emission gases of vehicles especially CO2 because of the global warming. Many vehicle companies including Toyota have launched various HEVs to satisfy the restriction laws and to improve the vehicle's efficiency. However, development for heavy-duty hybrid system is not plentiful rather than the passenger car. In this study, we choose the optimal size of engine, motor and battery for heavy-duty hybrid systems using dynamic programming. Also we analyze the correlation of the system's cost and efficiency because the added cost of vehicle to make the hybrid system is very important factor for the manufacturing companies. Finally, this study suggests a method to choose the appropriate system components size considering its performance and the cost. With this method, it is possible to select the component size for various systems.

• Journal of the Korean Institute of Gas
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• v.15 no.2
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• pp.15-20
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• 2011

Although CNG is able to meet the current emission standards, it is expected to be impossible to satisfy the requirements of the next EURO-6 emission regulation without an additional after-treatment device. Hydrogen is known to be a gaseous fuel which features the wide flammability limit and the fast reactivity. A certain amount of hydrogen addition to CNG is able to extend the lean combustion range and produce lesser amounts of harmful emissions. In this research, the combustion and emission characteristics of HCNG(mixture of Hydrogen and CNG) fuel were experimented in an 11-liter heavy duty lean burn engine varying hydrogen contents, air-to-fuel ratio and spark timing. The optimization of this HCNG engine for a city bus was performed through the evaluations of oxidation catalyst characteristics.

• Journal of Korean Society of Steel Construction
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• v.15 no.6 s.67
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• pp.649-660
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• 2003

The paper presents an evaluation of the tensile strength of the expansion anchor that can cause failure in the concrete based on the design of the anchorage. Tests of the heavy-duty anchor and the wedge anchor that are domestically manufactured and installed in plain concrete members are conducted to probe the effects of the embedded depth, concrete strength, and anchors spacing. The design of post-installed steel anchors is presented using the Concrete Capacity Design (CCD) approach. The CCD method is applied to predict the concrete failure load of the expansion anchor in plain concrete under monotonic loading for important applications. The concrete tension capacity of the fastenings with heavy-duty anchors and wedge anchors in plain concrete predicted using the CCD method is compared with the test results. For the CCD method, a normalization coefficient of 9.94 is appropriale for the nominal concrete breakout strength of an anchor or a group of wedge anchors in tension. On the other hand, a normalization coefficient of 11.50 is appropriate for the nominal concrete breakout strength of an anchor or a group of heavy-duty anchors in tension.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.1
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• pp.211-220
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• 2004

This paper presents the evaluation of pullout strengths of expansion anchors and wedge anchors that can cause a failure of the concrete on the basis of the design for anchorage. Tests are conducted for heavy-duty anchors and wedge anchors domestically manufactured and to be installed in plain concrete member. The mainly testing parameters reflected the effects of edge distance. Design of post-installed steel anchors is presented by the Concrete Capacity Design(CCD) in European Organization for Technical Approval. This approach is compared to the well-known provisions, ACI 349-90 specification. The use of both methods to predict the concrete failure load of expansion anchor in uncracked concrete under monotonic loading for important applications is compared. In this study, the concrete tension capacity of fastenings with Heavy-duty Anchors and Wedge Anchors in plain concrete predicted by ACI 349-90 and the Concrete Capacity Design method has been compared with the results of tests.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.537-548
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• 2022

It is important to design the pavement thickness considering heavy-duty traffic loads, which can cause excessive stress and strain in the pavement. Port-rear roads and industrial roads have many problems due to early stress in pavement because these have a higher ratio of heavy loads than general roads such as national roads and expressways. Internationally, composite pavement has been widely applied in pavement designs in heavy-duty areas. Composite pavement is established as an economic pavement type that can increase the design life by nearly double compared to that of existing pavement while also decreasing maintenance and user costs. This study suggests a thickness design method for composite pavement using roller-compacted concrete as a base material to ensure long-term serviceability in heavy-duty areas such as port-rear roads and industrial roads. A three-dimensional finite element analysis was conducted to investigate the mechanical behavior and the long-term pavement performance ultimately to suggest a thickness design method that considers changes in the material properties of the roller-compacted concrete (RCC) base layer. In addition, this study presents a user-friendly catalog design method for RCC-base composite pavement considering the concept of linear damage accumulation for each container trailer depending on the season.