• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.546-551
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• 2023

In this study, a beam steering measurement system was developed to perform functions such as far-field beam steering and near-field beam focusing for TX/RX modes in the near file of the AESA radar. The beam steering measurement system consists of a spherical near-field scanner, an antenna positioner, a near-field controller, a network analyzer, a radar control system, a verification radar, a simulated radio, and an AESA radar. Using the developed system, the characteristics of TX/RX patterns before and after installation of radome to AESA radar were measured, and the beam pattern was analyzed through conversion to far field-after near-field measurement.The boresight error of the radar antenna device was measured, and it was confirmed that the main lobes were formed the same before and after the simulated radar dome was mounted.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.3
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• pp.326-333
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• 2003

In the measurement using DMA and CPC in series, there is some time delay for particles classified in DMA to detect in CPC. During this time, the DMA time-response changes due to the velocity profile of sampling tube and the diffusion of particles in the volume that exists between the DMA exit and the detector of ultra-fine CPC. This is called mixing effect. In the accelerated measurement methods like the TSI -SMPS, the size distribution is obtained from the correlation between the time-varying electrical potential of the DMA and the corresponding particle concentrations sampled in DMA. If the DMA time -response changes during this delay time, this can cause the error of a size distribution measured by this accelerated technique. The kernel function considering this mixing effect using the residence time distribution is proposed by Russell et al. In this study, we obtained a size distribution using this kernel to compare to the result obtained by the commercial accelerated measurement system, TSI -SMPS for verification and considered the errors that result from the mixing effect with the geometric mean diameters of originally sampled particles, using virtually calculated responses obtained with this kernel as input data.

• Journal of Korea Water Resources Association
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• v.37 no.2
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• pp.155-161
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• 2004

The purpose of this study is to verify LSPIV technique. Verification was made using moving cart with known velocity. The difference of velocity values obtained using these methods are within 5％, which means that LSPIV can be used in the field with reasonable accuracy After verification, LSPIV was applied to the river. The Neungwon stream and the Gonjiam stream, tributaries of the Kyungan stream, were selected as the test sites for application. The results of the test application were compared with those obtained by 3-D electromagnetic current meter and electron-wave surface velocity meter. Results show that the velocity values obtained using LSPIV coincide well with those obtained using conventional devices with maximum difference of 8％.

• Macromolecular Research
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• v.17 no.5
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• pp.339-345
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• 2009

The core/shell type structure of the highly crosslinked poly(glycidylmetharylate-co-divinylbenzene) microspheres prepared in the precipitation polymerization in acetonitrile was thoroughly verified by means of swelling, $^1H$ NMR, XPS, TEM and TGA measurements. In the XPS measurement, the higher the GMA content, the higher the oxygen content was observed, implying that the higher content of GMA is observed in the particle surface. The further verification of the core/shell structure of the poly(GMA-co-DVB) particles was carried out using $^1H$ NMR and TEM techniques, resulting in the poly(GMA-co-DVB) particles with the GMA rich-phase and DVB rich-phase. In overall, the poly(GMA-co-DVB) microspheres consist of a highly crosslinked DVB rich-phase in the core and slightly or non-crosslinked GMA rich-phase in the shell part due to the different reaction ratios between two monomers and self-crosslinking density of DVB.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.247-252
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• 2004

Developed shape awareness technology and vision technology for optical ten slant in this research and including external form state of lens for the performance verification developed so that can be good achieve badness finding. And, establish to existing reflex data because inputting surface badness degree of scratch's standard specification condition directly, and error designed to distinguish from product more than schedule error to badness product by normalcy product within schedule extent after calculate the error comparing actuality measurement reflex data md standard reflex data mutually. Developed system to smallest 1pixel unit though measuring is possible 1pixel as 3.7$\mu\textrm{m}$${\times}$3.7$\mu\textrm{m}$(0.1369${\times}$10/sub-1/$\textrm{mm}^2$) the accuracy to 10/sub-1/mm minutely measuring is possible performance verification and trust ability through an experiment prove.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.12 s.243
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• pp.1653-1659
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• 2005

In this study, the performance of a DPRMs is evaluated and the measurement precision for the pile driving is presented. The DPRMs is a visual-measurement system for the pile rebound and the penetration movement using a high speed line-scan camera. The DPRMs generates the measurement deviation. It is caused by the strong impact for the pile driving. To reduce it, the vibration signal analysis about the pile driving is performed. As a result, it is confirmed that the tilting frequency of a camera-tripod structure corresponding to excitation frequency range of the ground is under 40Hz. Through the structure modification, the camera-tripod structure is redesigned to the model being free itself from the excitation frequency range of the ground. By the verification testing about the improvement effects, it is inspected that the tilting and measurement deviation of the redesigned DPRMs are reduced.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.4
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• pp.693-700
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• 2002

Recently, the mechanical structures applied to many industrial products, especially in electronic products, appear to be miniaturized and complicated. This trend makes it difficult to analyze the stress distribution of those mechanical structures and generates new challenges for precise measurement of strain. In order to solve this measurement problem many optical measurement techniques have been suggested. Among those, the ESPI(Electronic Speckle Pattern Interferometry) has been considered as one of the most useful tools. But the shortage of recognition and difficulties of measurement have limited its industrial applications in spite of its excellent capabilities. Therefore in this study, not only the verification of the FEA result but the enhancement of industrial application of ESPI was tried by measuring the in-plane displacement of mechanical structure with ESPI, which is difficult to be measured with strain gauge.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4317-4328
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• 2023

To ensure the measuring accuracy of the wall temperature, the outer wall temperature measurement values by using three kinds of thermocouple welding methods were analyzed and evaluated in the paper, including single-point flush-mounted in the wall groove method, single-point insert-mounted in the wall groove, and outer surface direct welding method, based on the application of a tube-in-tube condensing heat exchanger. And the impacts of silver, tin, and thermal resistance adhesive as filling materials on wall temperature measurement were also investigated, and the results were compared to that obtained without filling materials. The results showed that the wall temperatures measured by the three welding methods were lower than the theoretically calculated value. And the wall temperature measured by the outer surface direct welding method was lowest under the same experimental conditions. The wall temperatures measured by single-point flush-mounted and insert-mounted in the wall groove methods were also affected by different welding filling materials. It was found that the greater the thermal resistance of filling materials, the smaller the heat loss. By analyzing the reasons for the low measured value of wall temperature, a new wall temperature measurement method was developed to improve the accuracy of the current measurement method. Meanwhile, the outer wall temperature measurement experiments of vertical and horizontal heat transfer tubes were carried out to validate and calibrate the improved outer wall temperature measurement method. The results showed that the average outer wall temperature deviation measured by the improved wall temperature measurement method ranged from - 0.82% to +2.29% for vertical tubes and - 4.75% to - 1.44% for horizontal tubes, and the improved measurement method had good measurement accuracy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.671-674
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• 2016

We cytogenetically analyzed a triploid King-Nupchi strain of the olive flounder Paralichthys olivaceus to define the simplest, most rapid, and most effective method of ploidy analysis in aquaculture farms. Female triploidy of the flounder King-Nupchi strain was induced by cold shock (3 min post-fertilization at 2-4℃ for 45 min). Triploid induction was confirmed by erythrocyte measurement (nuclear volume, 29.15±2.10 μm³); flow cytometry (2.14±0.03 pg/cell); chromosome count (3N=72); Ag-NOR banding; and silver staining. Silver staining of finned cells obtained using a solid tissue technique was the most effective method of ploidy verification.

• Korean Journal of Community Nutrition
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• v.8 no.3
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• pp.319-326
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• 2003

The purposes of this study were: a) to develop the a quality measurement tool for the contract-managed hospital foodservice, and b) to evaluate their performance with the developed quality measurement tool, and c) to verify the reliability and validity of the quality measurement tool. The developed quality measurement tool comprised two parts, which were foodservice management and medical nutrition care service. The foodservice management part was classified into six functional categories which were Menu, Procurement and Storage, Production and Distribution, Facility and Utility, Sanitation and Safety, and Management and Evaluation. The medical nutrition care service part indicated the medical nutrition care provided. Quality measurement tool had 91 standards and 324 indicators. The quality measurement tools were distributed to the hospital foodservice manager employed by the foodservice company. The 324 indicators were measured by foodservice manager on the 5-Likert-type scales, and then adapted to a 100 point scale. The SPSS Ver. 11.0 was used for statistical analysis. The categories whose scores were evaluated as being high were Procurement', General Sanitation', Personal sanitation' and Waste' and the categories whose scores were evaluated as being low were Diet Order Manual', Standard Recipe', Appropriateness (Facility and Utility)', Check (Facility and Utility)'and Information Management'. All the categories of medical nutrition service were evaluated as having seriously low scores. Therefore, it was necessary for the contract-managed hospital foodservice to improve its performance in the area of medical nutrition care service. For the verification of the developed quality measurement tool, the reliability obtained by calculating Cronbach's α was 0.8747, and the content validity was also proved by scrutiny of the modification of the Professional group's techniques. (Korean J Community Nutrition 8(3) : 319∼326, 2003)