• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.74-80
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• 2005

It becomes necessary for engine manufactures to verify whether lots of engines on test bed during shop test are in compliance with NOx Technical Code for marine diesel engines more efficiently on the basis of engine group test concept which contains parent engine and member engines since all the engines are not needed to take NOx measurement. In addition, it becomes more obliged to consider parameters which affect NOx emission level and describe these parameters in NOx technical file as engine information and settings to define engine operation range with tolerance to make sure the engines are still in compliance with NOx emission limit on board after shop test. During preparation of engine group test for 4-stroke marine diesel engines, we evaluated NOx emission value under different engine operating conditions and found that there are certain parameters, for example, Charge air temperature and Max. cylinder pressure which have influence on NOx emission level. The NOx emission shall be satisfied with NOx technical code by means of controlling such parameters.

• Transactions of The Korea Fluid Power Systems Society
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• v.5 no.1
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• pp.6-12
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• 2008

ISO pneumatic cylinder reliability test requires air leakage measurement. Air cylinder has many parts and the leakage shall be measured before, during and after endurance test, and, the leakage should smaller than the specified value. The existing measurement method needs complex operation and the calibration of leak detector, and, has to separate the testing cylinder from endurance test device, which causes the change of contact condition of seal in the cylinder. Therefore, it is hard to evaluate the air leakage during endurance test, and guarantee the reliability of the conventional measurement method. In this paper, a new method for air leakage measurement using isothermal chamber, which does not requires calibration or temperature compensation, and, can measure air leakage accurately with quite simple operations, is proposed. As a result, reliability of air leakage measurement can be improved because the proposed method does not have to separate the testing cylinder from the endurance test device for air leakage measurement. The effectiveness of the proposed method is proved by error analysis of leak measurement from experimental result.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.257-264
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• 2015

This study is intended to provide navigator with specific information necessary to assist the avoidance of collision and the operation of ships to evaluate the maneuverability of dead weight tonnage 8,000 tons Oil/Chemical tanker. The actual maneuvering characteristics of ship can be adequately judged from the results of typical ship trials. Author carried out sea trials based full scale for turning test, Z" maneuvering test, man overboard rescue maneuver test, inertia stopping test. Consequently, $2^{st}$ Overshoot yaw angle of the semi balanced rudder and flap rudder in ${\pm}20^{\circ}$ zig-zag test showed $22.2^{\circ}$ and $18.0^{\circ}$, respectively. The maneuverability of the vessel was good in the flap rudder. The man overboard rescue maneuver maneuverability test was most favorable in the flap rudder and the full load condition. The results from tests could be compared directly with the standards of maneuverability of IMO and consequently the maneuvering qualities of the ship is full satisfied with its.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.44-52
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• 2007

Recently, oystershell wastes cause serious environmental problem and the need for the researches on the recycling of oystershell have been increased and various methods are already in operation. Field plate bearing tests and numerical analysis were performed to investigate the bearing capacity of oystershell filled geotextile gabion which utilized the waste oystershell at the coastal oyster farm site. The waste oystershell mixed soil specimens were prepared for the laboratory test and field test in terms of varying blending ratio of granite soil and oystershell. Based on the cyclic plate load test results, the spring constant, subgrade modulus of ground, and the reinforcing parameters were determined. The field plate load test results indicate that the bearing capacity of the soil ground with the oystershell mixed ratio of 20% is greater than that of the original ground. Two-dimensional numerical analysis was evaluated the expected deformation in the given conditions. Analysis results show a similar characteristics on bearing capacity with the results of the field plate load test. These findings suggest that the oystershells are very promising construction materials for landfill and earth embankment in coastal area.

• Journal of Korean Society for Quality Management
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• v.48 no.1
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• pp.215-225
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• 2020

Purpose: The purpose of this study was to show current states of domestic Precision Guided Missile(PGM) by analyzing Live-fire test results using general methods to get the Confidence Levels. Methods: Live-fire test results were used to get Confidence Levels of PGM. The Confidence Levels were derived by two general methods. The first method was Binomial distribution and second was convergence of Hypergeometric distribution and Bayes' rule. Results: The results of this study are as follows; The more Live-fire tests of PGM are performed, the higher Confidence Level of PGM will be estimated. And the number of Live-fire tests are related to a unit price of PGM. This results means that the increase of live-fire test, which is useful data for preparation and evaluation of Development Tests / Operation Tests for PGMs, is only way to enhance the Confidence Levels of each PGMs. Conclusion: This study shows the relationship between the Live-fire tests and Confidence Levels of PGMs and it will be used on Live-fire Test & Evaluation of PGMs for reference.

• Journal of the Korean Society of Propulsion Engineers
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• v.7 no.3
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• pp.53-60
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• 2003

A test stand was developed to measure static performance of a reciprocating engine on the ground, related to the small aircraft being developed by KARI. The test stand consists of an apparatus to install and operate a pusher-type propulsion system and a data acquisition system to process many performance parameters including engine torque and propeller thrust as well as monitoring of the engine operations. First, the performance data from the basic operation tests were compared with the original engine data so the capacity of the test stand was verified. Engine performance tests were carried out with various test conditions through three stages, and it was measured and analyzed that the manifold pressure, the torque, and the back pressure of the engine, and the static thrust of the propeller.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.339-342
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• 2010

Doosan Heavy Industries & Construction Co., Ltd. constructed a gas turbine engine test cell to verify operating characteristics and design parameters of 5MW class gas turbine engine for power generation under developing. Engine test cell was designed to satisfy critical requirements to scrutinize all performance parameters of the engine with safe and reliability in accordance with design specification. As the test cell developed can effectively reproduce engine operation conditions covering from start-up to maximum power condition, it can be utilized to make a continuing design improvement of the engine based on practical test data at full stretch. Moreover, it is expected to be serviceable to develop derivative engines and be utilized to put them into serial production and contribute to a competitiveness reenforcement as a gas turbine engine manufacturer.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.2 s.257
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• pp.253-259
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• 2007

A new material tester has been developed to measure mechanical properties of thin film specimens at high temperature. It is useful for observing oxide film growth or local deformation on the surface, and for measuring creep strength. Main characteristics of the tester is as follows; First, high temperature is achieved by Joule heating generated by electricity passing through the specimen, which does not need to enclose the specimen by a furnace or a heating chamber. The exposed specimen enables one to observe the surface during the test. Because the overall size of the test rig is compact, the whole test rig can be placed in a chamber for environmental controlled tests. The loading device is from a level scales. Not only static load with fixed counter weight, but also variable load by moving counter weight controlled remotely can be applied for an ordinary creep test and creep-fatigue test, respectively. The detail of the construction, operation principle, and the specification are described. And also, an example of test result obtained using the creep tester is presented.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2731-2738
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• 2015

The importance of disaster observation facilities and system are increasing around the world in order to predict and prevent water disasters, which cause serious damage to life and property. A performance test center was built to stabilize performance, compatibility, and reliability of devices, and to verify new S/W. The aim of this study is to make a guideline to build standard verifying system for hydrological observation devices by building the performance test center. In addition, efficiency of management and operation of hydrological devices can be enhanced through device analysis, maintenance, database building, and grade certificate publishment after the device test.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.776-792
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• 2021

Conventional integral effect test facilities were constructed to enable the precise observation of thermal-hydraulic phenomena and reactor behaviors under postulated accident conditions to prove reactor safety. Although these facilities improved the understanding of thermal-hydraulic phenomena and reactor safety, applications of new technologies and their performance tests have been limited owing to the cost and large scale of the facilities. Various nuclear technologies converging 4th industrial revolution technologies such as artificial intelligence, drone, and 3D printing, are being developed to improve plant management strategies. Additionally, new conceptual passive safety systems are being developed to enhance reactor safety. A new integral effect test facility having a noticeable scaling ratio, i.e., the (UNIST reactor innovation loop (URI-LO), is designed and constructed to improve the technical quality of these technologies by performance and feasibility tests. In particular, the URI-LO, which is constructed using a transparent material, enables better visualization and provides physical insights on multidimensional phenomena inside the reactor system. The facility design based on three-level approach is qualitatively validated with preliminary analyses, and its functionality as a test facility is confirmed through a series of experiments. The design feature, design validation, functionality test, and future utilization of the URI-LO are introduced.