강재를 대처할 수 있는 다양한 복합재료 중 CFRP (Carbon Fiber Reinforced Polymer)를 사용하여 인장 물성 실험을 실시한다. KS F ISO 10406 (콘크리트용 섬유강화 폴리며(FRP 보강재 - 시험방법) 에서 FRP의 측정길이는 지름 (D)의 40 배를 기준으로 제시되어진다. 그러나 25 mm 이상의 시험체는 양단 보강부를 포함하게 된다면 대략 2 m 이상으로 제작되어지게 되고 시험이 상당히 번거롭게 됨으 로써 시험법 개선을 위해서 측정 길이별로 설정하여 성능평가 후 비교분석 한다.
Abstract Purpose : The purpose of this study is to evaluate the differences and reliability of various methods for measuring Interpupillary Distance. Methods : The participants were 50 Cambodian adults (28.08±3.85 years old) without ocular disease and abnormal binocular vision. Far/near IPD was measured using Corneal reflection pupillometer, PD ruller and spotting, and calculated formula for fixation distance. Using each method, the pupil distance of both eyes was measured three times, respectively, and the average value was recorded. Results : The average value of the corneal reflection pupilometer in the distance was 63.08±3.42 mm, the average value of PD calculated formula was 62.97±3.41 mm, the average value of the PD ruler was 63.72±3.17 mm, and the average value of the spotting method was 63.89±3.15 mm. The average value of the corneal reflection pupilometer in the near was 59.85±3.23 mm, the average value of the calculated formula for fixation distance was 59.95±3.23 mm, the average value of PD ruler was 59.72±3.29 mm, and the average value spotting method was 59.47±3.23 mm. Comparison between various methods in the distance and near showed statistically significant differences (p<0.001). Conclusion : In the comparative analysis between each method, the corneal reflection pupillometer is considered to be the most accurate method, but since there is no significant difference from the average value of the Spotting method, the PD Ruler Viktorin method, and the calculated formula for fixation distance, whichever method is used, it is clinically acceptable. Therefore it is believed that each method is compatible with each other. Key words : Corneal reflection pupillometer, PD meter, PD ruler, Spotting
본 연구는 EMG(electromyography) 텍스타일 전극 개발을 목적으로 레이어 수의 디자인 및 원단을 다르게 하여 성능 및 신호 획득 안정성을 평가한다. 레이징 및 프레스 공정을 통하여 텍스타일 전극을 제조하며 Layer-0, Layer-1, Layer-2로 레이어 유무 및 수에 따른 결과를 분석했다. 이에 레이어 유무에 따라서는 근활성 측정에 영향을, 수가 많을수록 높은 성능이 나타남을 확인할 수 있었다. Layer-2 구조로 통일하여 5가지의 원단(네오프렌, 스판덱스 쿠션, 폴리에스테르 100%, 나일론 스판덱스, 광목 캔버스)으로 전극을 제조해 실험해 보았다. 성능적인 면에서, 원단의 중 량이 높은 나일론 스판덱스가 높은 성능을 보였으며, 스판쿠션 텍스타일 전극이 근활성도 수득에 높은 안정성을 보 였다. 이에 위 연구는 레이어에 따른 성능 연관성과 전극-피부사이의 닿는 면적 간의 관계 등을 고찰하여 슬리브 전체의 의복압을 늘리는 대신 특정 센서 측정 부위에만 높은 압력을 가함으로 차후 연구에서 레이어의 수 및 물성에 따른 전극의 공학적 설계 가능성을 제시한 의의가 있다.
One of the options for spent fuel dry storage systems is to store them in canisters using metal or concrete casks close to shore. The interaction between the austenitic stainless steel and the chloride atmosphere generated from the sea creates detrimental conditions leading to chloride induced stress corrosion cracking (CISCC) in the canister. The corrosion integrity of the canister in the concrete cask is very important because the canister is sealed and used for a long period of time. A canister made of austenitic stainless steel has several welding lines on the wall and lid, which are generated during the welding process and have high residual tensile stress. The interaction between the austenitic stainless steel and the chloride atmosphere generated from the sea creates detrimental conditions leading to chloride induced stress corrosion cracking (CISCC) in the canister. The corrosion integrity of the canister in the concrete cask is very important because the canister is sealed and used for a long period of time. In order to evaluate such soundness, an accelerated test capable of simulating the CISCC crack propagation phenomenon of the canister weld is required. In this study, a test device for performing the CISCC simulation test was constructed using the DCPD device. The direct current potential drop (DCPD) technique is a widely accepted method of monitoring crack initiation and growth in controlled laboratory tests. Total 10 types of test specimens with varying welds, base metal, salinity and stress were selected and a sealed chamber with DCPD test apparatus were designed and constructed to evaluate them. The chamber for CISCC simulation was manufactured as a sealed with a solution containing 10% MgCl2. A 1/2 CT specimen with precracked pre-cracks was loaded into the prepared container, and gauze was attached from the bottom for smooth delivery to the specimen to facilitate penetration of chloride. After the test, the measured DCPD data were correlated with Electron Back scattered Diffraction (EBSD) data.
A lot of CANDU Spent Fuels (CSFs) have been stored in spent nuclear fuel pools and dry storage facilities. In accordance with the enhanced nuclear regulations, the initial characteristics of CSF should be inspected to ensure the integrity of CSF and the reliable operation of storage system before loading it into a cask for long-term dry storage. For the inspections, an initial characteristics measurement equipment was designed, which is used for Pool-Side Examination (PSE) in the spent fuel pool of the pressurized heavy water reactor nuclear power plant. Measurements using the equipment consist of non-contact inspections and contact inspections. The non-contact inspections do not affect CSF integrity, whereas the integrity of CSF can be reduced during the contact inspections under abnormal operating conditions because the probe of equipment may apply specific loads to the CSF. Therefore, the structural integrity evaluations of equipment and CSF are performed using Finite Element (FE) analyses for four combinations based on two abnormal conditions and two probe positions. The used abnormal conditions are the pressing load condition and the scratching load condition, and two probe positions are the center and bottom of the fuel rod in the longitudinal direction, respectively. In this evaluation, the bottoms of the fuel rod or CSF are defined as the regions facing the bottom surface of equipment. The analysis of the pressing load condition is performed by pressing the probe of the equipment in radial direction of the CSF fuel rod. That of the scratching load condition is carried out by applying a specific radial load to the CSF fuel rod using the probe and then applying the load to the surface of the fuel rod while moving axially along the surface. All combinations are analyzed considering geometric, boundary and material non-linearity under the dynamic load, which is dependent on the equipment operating velocity. The stresses of CSF and equipment components were obtained from these analyses. The maximum stress of each component was generated at the combination on the scratching load condition for the bottom position among the four combinations. The obtained maximum stresses are lower than the yield stress for each component material. Also, the CSF is not overturned due to the support plate of the equipment in all analyses. Therefore, the structural integrity and safety of the equipment and the CSF are maintained under abnormal operating conditions during the inspection using the initial characteristic measurement equipment.
본 연구에서는 광섬유를 이용한 탄소섬유복합재료(CFRP) 긴장재 개발을 목표로 다양한 성능실험을 수행하였다. 광섬 유 센서를 활용한 탄소섬유 긴장재의 계측성능은 부착된 변형률 게이지의 계측 값과 비교한 결과, 3.7% 이내로 동일한 계측을 하는 것으로 나타났고, 탄소섬유 긴장재 파단까지 계측이 가능하기 때문에, 센싱용 긴장재로 활용이 가능함을 확인하였다. 현장 적용을 위한 장기성능 실험결과, 릴렉세이션의 경우 저릴렉세이션 강연선 기준 값인 2.5%를 만족하였고 피로시험의 경우 도로 교설계기준을 준용하여 200만회 이후 인장성능의 변화가 없는 것을 확인되어, 탄소섬유 긴장재 뿐만 아니라 정착구도 장기성능 을 확보한 것으로 판단된다
Decommissioning plan of nuclear facilities require the radiological characterizations and the establishment of a decommissioning process that can ensure the safety and efficiency of the decommissioning workers. By utilizing the rapidly developed ICT technology, we have developed a technology that can acquire, analyze, and deliver information from the decommissioning work area to ensure the safety of decommissioning workers, optimize the decommissioning process, and actively respond to various decommissioning situations. The established a surveillance system that monitors nuclide inventory and radiation dose distribution at dismantling work area in real time and wireless transmits data for evaluation. Developed an evaluation program based on an evaluation model for optimizing the dismantling process by linking real-time measurement information. We developed a technology that can detect the location of dismantling workers in real time using stereovision cameras and artificial intelligence technology. The developed technology can be used for safety evaluation of dismantling workers and process optimization evaluation by linking the radionuclides inventory and dose distribution in dismantling work space of decommissioning nuclear power plant in the future.
Background: The Natural killer cell activity measurement test of the ELISA method developed by company A could have many economic benefits in terms of cost and time compared to the existing 'cytotoxicity test method'. A portable incubator capable of culturing the specimen while moving was developed as a way to save test time and secure the stability of the specimen when transferring the specimen to the entrusted institution.
Objectives: This study investigated efficacy evaluation of NK cell activity measurement in a portable incubator.
Design: Experimental research.
Methods: 100 participants were selected to measure NK cell activity. The collected blood was placed in a general incubator and a portable incubator at the same time to start culturing, and the plasma was separated by centrifugation. The NK cell activity test was measured by enzyme immunometry.
Results: In the verification of the culturing performance of the developed portable incuvator, no significance was found between the general incuvator and the portable incuvator, and the same performance was maintained in culture.
Conclusion: Portable incubators have a great effect on shortening the test time and securing the stability of samples.
This study evaluates the ammonia (NH3) reduction effect of Bio-curtains (hereinafter referred to as curtains) utilized for odor control in pig farms based on the distance outside the curtain and the spraying condition. The curtain (total area: 37.9m3) was constructed with two layers of light-shielding screens stretched over a rectangular parallelepiped structure installed around a ventilation fan (630 mm) on the side wall of a pig barn where 48 finishing pigs were reared. The real-time NH3 concentration was measured by using a photoacoustic spectrometer. In the first part of this study, the NH3 measurement position for each side of the curtain was selected based on the lowest standard deviation among 4 to 8 initial sampling points on the surface of the curtain and utilized for both experiments of distance and spraying. In the experiment concerning the distance outside the curtain, ammonia concentration decreased by 17.45% at 2m compared to the distance at 5 cm and by 6.94% at 4m compared to 2m on average. In contrast, the NH3 reduction rate for each distance compared to the ventilation fan was the lowest at the 100% operating rate in which the exhausted NH3 concentration from the ventilation fan was low. At this time, the spraying mist on the inside of the curtain increased the NH3 reduction rate by 4.98 to 10.36% compared to the non-spraying condition. Consequently, the NH3 be reduced as distance outside the curtain increases due to the diffusion effect caused by the surrounding wind and the spraying mist on the inside curtain on the dissolution of NH3.
최근 3차원 영상 데이터 활용 기술이 주목받으며 레이저 스캐너, 깊이 카메라와 같은 장비를 활용하여 작물의 생육을 측정하려는 연구가 시도되고 있다. 작물의 생육 특성을 측정할 때 3차원 영상 데이터를 활용한다면 평면 데이터에서 측정하지 못한 구조와 형태 정보를 이용할 수 있는 장점이 있다. 본 연구에서는 콩의 생육 특성을 3차원 영상 데이터를 활용하여 추정하였다. 깊이 카메라를 이용하여 콩의 개화시(R1), 착협기(R3), 종실비대기(R5) 에 촬영하고 3차원 데이터로 개체의 초장과 엽면적을 추정하고 실측 값과 비교하였다. 초장 추정을 위해 평면에 투영된 개체의 무게 중심을 이용하여 원줄기의 x, y 좌표 위치를 지정하였는데 눈으로 보고 지정한 원줄기의 위치와 무게 중심 점의 x, y 좌표 위치는 높은 결정 계수를 보였다. 초장 추정의 경우 콩의 구조와 형태가 발달함에 따라 3차원 영상에서 지면으로부터 개체 상단 지점 간 거리를 이용하는 방법은 실측과 추정 값간 오차가 컸다. 엽면적 추정을 위해서 3차원 위치 값을 갖는 개체 표면 점들을 높이에 따라 분할하고 각 높이 구간의 면적을 계산하였다. 3차원 데이터 병합 과정에서 늘어난 점 개수로 인해 각 높이 구간에서 계산된 면적이 증가하였기 때문에 추정 값은 과대평가되었다. 향후 3차원 영상을 이용한 보다 정밀한 생육 조사를 위해서는 작물 고유의 생육변수 특성을 고려한 데이터 전처리 과정과 분석 방법 개발이 필요할 것으로 사료된다.
Surface contaminants may attach to surfaces or objects in the radiation controlled area to cause radiation exposure, or spread out to the general environment by person and object exiting the radiation workplace. Accordingly, in radiological safety control, surface contamination monitoring is one of the important factors in workplace monitoring. When obtaining the measurement results for the monitoring, the results are accompanied by uncertainty since measurements contain numerous errors. Accordingly, the International Organization for Standardization (ISO) has published the ISO 7503 series which is comprehensive and detailed guidelines on the measurement and evaluation of surface contamination. ISO 7503-3 especially presents a mathematical model for the contamination measurement and provide calculation guidelines on measurement uncertainty evaluation, decision threshold and detection limit. This paper is focused on reevaluating and comparing the surface contamination monitoring method applied to radiation safety management practice and its results based on the measurement and evaluation method set by the International Organization for Standardization. The evaluation was performed in accordance with ISO 7503, and the current reporting method for measurement results was compared with the method recommended in ISO 11929 publication.
The Republic of Korea is implementing safeguards for domestic nuclear facilities through cooperation with the IAEA. But it is not to evaluate the material balance for the material unaccounted for, MUF in the bulk handling facility. Although the development of a material balance evaluation program is underway, there are no related regulations. The State Regulatory Authority, SRA is performing material balance evaluation, MBE on the facility based on the design information and material balance results of the facility. However, it is not possible to directly derive measurement uncertainty for the facility’s measurement equipment, which is an important variable of MBE. To solve this problem, it is trying to derive a method suitable for the domestic environment by investigating the some measurement uncertainty estimation methods and analyzing characteristics of them. In this study, the traditional measurement uncertainty estimation method, GUM method and GUM-S1 method were studied and the advantages and disadvantages were analyzed. Due to the problems mentioned above, the uncertainty quantification technique currently being used cannot be applied to the evaluation of the domestic material balance. Therefore, we are tying to apply them to the evaluation the domestic material balance through the above three methods or a combination of them appropriately. Through this continuing study, it is expected that it will be possible to present a plan to derive measurement uncertainty optimized for the domestic MBE environment.
Failure to comply with the performance test requirements for the centrifugal pumps at power plants often results in performance dissatisfaction as a result of field tests. This study proposed a method of reducing the uncertainty of the field test results by evaluating the systematic error in the measurement system caused by failure to follow the test requirements using the computational fluid dynamics(CFD) technique. As a result of the evaluation of the systematic error and reflecting it in the performance test data, it was confirmed that the error occurred at a constant rate with respect to the flowrate and that the pump, which showed a difference in performance actually had the same performance.
Due to the Fukushima nuclear accident, a large amount of radioactive material was released into the atmosphere, and consequently, it spread over a wide area and was deposited into the soil. As a result of this, a wide area of radioactive contamination site was created. Due to the contaminated site, the need for research on various exploration platforms for efficient situation management and field response is being emphasized. Backpack-type radiation survey & monitoring equipment is useful for creating a contamination maps containing information such as Dose Rate, Radionuclide, Activity Concentration accompanied by spatial analysis when performing a Scan Survey that moves with a backpack on a wide area site. contamination maps are based on accurate radiological characteristic information. However, there is a problem in that the accuracy of the evaluation results is lowered due to changes in environment conditions or the variability of the dose rate and counting rate during scan survey. This problem should be solved by applying the influence of each variable to the underlying data. However, prior to this, it is most important to prepare the base underlying first. And this can be obtained through evaluation of detection performance through static survey. Therefore, in this study, the change in detection efficiency for the measurement height and radius of the backpack-type radiation survey & monitoring equipment based on the 3"×3" NaI(Ti) detector was evaluated. First, the height of the source and Backpack-type radiation survey & monitoring equipment was evaluated from 0 cm to 1 m, which is the height of the soil and detector when an adult male wears a backpack. The experiment was conducted using the 137Cs (383 kBq) point source, which is a nuclide mainly detected at the contaminated site. The measurement time was measured five times per one minute, considering that it was backpack-type equipment and a future scan survey. In addition, in order to evaluate the detection radius, the measurement was performed by changing the measurement distance up to 5 m at intervals of 50 cm. As a result of evaluating the detection performance of the backpack-type radiation surveys & monitoring equipment, it was confirmed that increasing the detection height and radius reduces the count rate in the form of an exponential function. In addition, it was confirmed that the detected radius varies depending on the height. Based on these results, we plan to conduct additional research to understand the scan survey and its sensitivity to various factors. Through this, the company plans to develop various models for exploring the site by improving the accuracy of backpack-type radiation surveys & monitoring equipment.
For the peaceful use of nuclear energy, the international community has devoted itself to fulfilling its obligations under the Safeguards Agreement with IAEA. In this regard, uranium in a radioactive waste drum should be analyzed and reported in terms of mass and 235U enrichment. In order to characterize radioactive wastes, gamma spectroscopy techniques can be effectively applied. In the case of high-resolution gamma spectroscopy, because an HPGe detector can provide excellent energy resolution, it can be applied to analyze a mixture having a complicated isotopic composition. However, other substances such as wood, concrete, and ash are mixed in radioactive waste with various form factors; hence, the efficiency calibration is difficult. On the other hand, In Situ Object Counting System (ISOCS) has a capability of efficiency calibration without standard materials, making it possible to analyze complex radioactive wastes. In this study, the analysis procedure with the ISOCS was optimized for quantification of radioactive waste. To this end, a standard radioactive waste drum at KEPCO NF and low-level radioactive waste drums at Korea Radioactive Waste Agency (KORAD) were measured. The performance of the ISOCS was then evaluated by Monte Carlo simulations, Multi-Group Analysis for Uranium (MGAU) code, and destructive analysis. As a result, the ISOCS showed good performance in the quantification of uranium for a drum with the homogenized simple geometry and long measurement time. It is confirmed that the ISOCS gamma spectroscopy technique could be used for control and accountancy of nuclear materials contained in a radioactive waste drum.
With the advancement of industrialization, modern industry had sophisticated technology, and manufacturers also demanded high-precision measurement accuracy. Improving the quality level by increasing the reliability of measurement results as well as accurate measurement is a key issue to increase the competitiveness of today's manufacturing industry. In general, measurement results depend on tolerances in the industrial field, and it may be difficult to guarantee the reliability of the data in the case of an industry that deals with precision parts. Currently, measurement uncertainty is mainly applied to the calibration and test fields of instruments. This study is aim to apply measurement uncertainty as a way to improve the accurate analysis and reliability of measurement results in the industrial field. For this, precision parts connected by shaft and hole were selected among geometric elements, and roundness and cylindricity were measured using a roundness measuring instrument and CMM. And, taking into account the environment in which these measurements were made, factors affecting the measurement results were derived, and a mathematical model was established to calculate the measurement uncertainty. Applying uncertainty in the field in this way is expected to improve the level of quality and accurate analysis of measurement results.
PURPOSES : The purpose of this study is to suggest a thermal expansion coefficient measurement method using an embedded strain transducer (EST) and vibrating wire gauge (VWG), as well as to evaluate the reliability of the proposed methods by comparing them with the AASHTO T 336-10 standard method.
METHODS : To apply the AASHTO 336-10 test method, which is the criterion for reliability evaluation, a reference specimen using stainless steel (sus304) is manufactured, and a thermal expansion coefficient of 17.308με/°C is obtained based on ISO regulations. Using the reference specimen, the correction factor of the thermal expansion coefficient measurement equipment is measured to be 2.93με/°C, and using this value, the thermal expansion coefficient of the mortar specimen containing the embedded gauges is measured accurately. The reliability of the proposed experimental method is evaluated by measuring the thermal expansion coefficient of the embedded gauge with temperature compensation and then comparing it with that of the reference specimen.
RESULTS : The coefficient of thermal expansion of the mortar specimen is measured to be 12.423με/°C based on AASHTO 336-10, 11.963με/°C using the EST method, and 12.522με/°C using the VWG method. Based on the results obtained using the AASHTO method, the embedded gauges show a difference of 1%~3% in terms of the average results, as well as a difference in the standard deviation of 0.059~0.186. Therefore, our level of confidence in the thermal expansion coefficient experiment using the embedded gauges is high.
CONCLUSIONS : When using the AASHTO 336-10 test method, the thermal expansion coefficient should be obtained by measuring the length change of the specimen; however, some engineering judgment of the experimenter is required when the measurement values fluctuate during the temperature stabilization period. In the thermal expansion coefficient test using embedded gauges (EST and VWG), temperature compensation must be performed. Furthermore, it is assumed that the temperature difference between the water tank and test specimen does not significantly affect the thermal expansion coefficient measurement because the important point is not the actual temperature value but the temperature gradient. For reliability evaluation, a statistical significance review of the strain distribution by measurement method is performed via a T-test comparing with the AASHTO test result (12.423με/°C) and the reliability level for each measurement method remains confidential.