• Journal of the Korean Solar Energy Society
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• v.29 no.2
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• pp.70-75
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• 2009

In this experiment, we did sampling 6 kinds of photovoltaic modules and analyzed the discrepancy of measurement results between l laboratory and 4 PV makers to have performance repeatability at Standard Test Condition(STC) condition. From the KIER's results, Korea's standard test laboratory, other laboratory showed -10% measurement variation. The causes came from correction of reference cell, test condition and the state of skill. Form the comparison test, we analyzed the problems. But three PV maker reduced measurement variation, other one PV maker and one test laboratory didn't improve the problems of correction of reference cell, test condition and the state of skill. Also, High Efficiency Module had a big discrepancy of -10.0$\sim$-6.2% among 3 laboratories which have a less than 10msec light pulse duration time. This made low spectrum response speed so the Fill Factor decreased maximum output power under 10msec light pulse duration time

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.1
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• pp.57-69
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• 2020

Purpose - This study examines what are the asset market fluctuations in Europe and how each economic variable affects major variables, and explore the dynamics of housing and stock market through Greece. The variables under consideration are balance on current account (BCA), index of stock (STOCK), gross domestic product (GDP), housing price indices (HOUSING), M3, real rate of interest (IR_REAL) and household credits (LOAN). We investigate the functional and causal relationships between housing and stock market. Research design, data, and methodology - Vector error correction model (VECM) is used to figure out the dynamic relationships among variables. This study also contains the augmented Dickey-Fuller unit root, cointegration, Granger causality test, and impulse response function and variance decomposition analysis by EViews 11.0. Results - The statistical tests show that all variables under consideration have one unit root and there is a longterm equilibrium relationship among variables for Greece. GDP, IR_REAL, M3, STOCK and LOAN can be considered as causal factors to affect real estate market, while GDP, LOAN, M3, BCA and HOUSING can bring direct effects to stock market in Greece. Conclusions - It can be judged that the policy that affects the lending policy of financial institutions may be more effective than the indirect variable such as monetary interest rate.

• Radiation Oncology Journal
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• v.36 no.3
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• pp.248-253
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• 2018

Radiation protection in the scrotum to reduce the risk of genetic effect in the future is very important. This study aimed to measure the scrotal dose outside the treatment fields by using the radio-photoluminescence glass dosimeter (RPLGD). The characteristics of RPLGD model GD-302M were studied. Scattered dose to scrotum was measured in one liposarcoma case with the prescribed dose of 60 Gy. RPLGDs were placed in three different locations: one RPLGD was positioned at the posterior area which closer to the scrotum, and the other two RPLGDs were placed between the penis and the scrotum. Three RPLGDs were employed in each location. The scattered doses were measured in every fraction during the whole course of treatment. The entire number of 100 RPLGDs showed the uniformity within ±2%. The signal from RPLGD demonstrated linear proportion to the radiation dose (r = 0.999). The relative energy response correction factor was 1.05. The average scrotal dose was 4.1 ± 0.9 cGy per fraction. The results presented a wide range since there was a high uncertainty during RPLGD placement. The total scrotal dose for the whole course of treatment was 101.9 cGy (1.7% of the prescribed dose). The RPLGD model GD-302M could be used to measure scattered dose after applying the relative energy correction factor.

• Journal of Korean Neurosurgical Society
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• v.67 no.2
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• pp.137-145
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• 2024

In adult spinal deformity (ASD) surgery, mechanical failure (MF) has been a significant concern for spine surgeons as well as patients. Despite earnest endeavors to prevent MF, the absence of a definitive consensus persists, owing to the intricate interplay of multifarious factors associated with this complication. Previous approaches centered around global spinal alignment have yielded limited success in entirely forestalling MF. These methodologies, albeit valuable, exhibited limitations by neglecting to encompass global balance and compensatory mechanisms within their purview. In response to this concern, an in-depth comprehension of global balance and compensatory mechanisms emerges as imperative. In this discourse, the center of gravity and the gravity line are gaining attention in recent investigations pertaining to global balance. This narrative review aims to provide an overview of the global balance and a comprehensive understanding of related concepts and knowledge. Moreover, it delves into the clinical ramifications of the contemporary optimal correction paradigm to furnish an encompassing understanding of global balance and the current optimal correction strategies within the context of ASD surgery. By doing so, it endeavors to furnish spine surgeons with a guiding compass, enriching their decision-making process as they navigate the intricate terrain of ASD surgical interventions.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.505-510
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• 2014

Normalized Difference Vegetation Index (NDVI) is a major indicator for monitoring climate change and detecting vegetation coverage. In order to retrieve NDVI, it is preprocessed using cloud masking and atmospheric correction. However, the preprocessed NDVI still has abnormally low values known as noise which appears in the long-term time series due to rainfall, snow and incomplete cloud masking. An existing method of using polynomial regression has some problems such as overestimation and noise detectability. Thereby, this study suggests a simple method using amoving average approach for correcting NDVI noises using SPOT/VEGETATION S10 Product. The results of the moving average method were compared with those of the polynomial regression. The results showed that the moving average method is better than the former approach in correcting NDVI noise.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.3
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• pp.292-305
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• 2013

This study reported present state of clothing technical designers' work duties and working conditions, so as to suggest effective ways to develop professional training methods for them. Technical designers working for vendors and agents were surveyed as they represent the majority of technical designers in Korean clothing industries. Survey participants were 62 technical designers working for 6 clothing vendors and 2 clothing agents, and the survey closely inspected their work qualifications, duties and responsibilities, working conditions and training conditions. Survey was conducted from June $27^{th}$ to July $17^{th}$, 2012. The questionnaire examined frequency analysis and multiple response analysis using SPSS 19.0 Windows after investigating documents and work fields through personal experiences and interviews from technical designers for data collection and analysis. A chi-square test analyzed the preferred type of fitting for technical designers of vendors and agents. The results showed that 32.3% of those surveyed have more than 7 years of work experience and the highest level of education is predominantly a bachelor's degree (57 people, 91.9%). Among the work responsibilities, respondents did sample measuring more than four times a day. Also, the results showed that technical designers needed to qualify: first 'Fitting Technic', second 'Pattern Correction Capability', and third 'English Skills to Communicate with Buyers'; subsequently, education on several technics (such as measuring, grading, and fitting) were required for the job. Current technical designers answered that they need more various work-related education. However, the analyzed results showed that pre work-related training was insufficient. The data shows that technical designers require re-education in 'Pattern Correction Method' (61.3%) and 'Sewing Education' (64.5%).

• Journal of Ocean Engineering and Technology
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• v.29 no.3
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• pp.217-223
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• 2015

In order to predict the motions of a planing hull in waves, it is necessary to accurately estimate the force components acting on the hull such as the hydrodynamic force, buoyancy, and friction, as well as the wave exciting force. In particular, based on strip theory, hydrodynamic forces can be estimated by the summation of the forces acting on each cross-section of the hull. A non-linear strip method for planing hulls was mathematically developed by Zarnick, and his formula has been used to predict the vertical motions of prismatic planing hulls in regular waves. In this study, several improvements were added to Zarnick's formula to predict the vertical motions of warped planing hulls. Based on calm water model test results, the buoyancy force and moment correction coefficients were modified. Further improvements were made in the pile-up correction. Pile-up correction factors were changed according to variations of the deadrise angles using the results found in previous research. Using the same hull form, captive model tests were carried out in other recent research, and the results were compared with the present calculation results. The comparison showed reasonably good agreements between the model tests and present calculations.

• Nuclear Engineering and Technology
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• v.47 no.7
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• pp.939-944
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• 2015

The calibration methods of neutron-measuring devices such as the neutron survey meter have advantages and disadvantages. To compare the calibration factors obtained by the shadow cone method and semi-empirical method, 10 neutron survey meters of five different types were used in this study. This experiment was performed at the Korea Atomic Energy Research Institute (KAERI; Daejeon, South Korea), and the calibration neutron fields were constructed using a $^{252}Californium$ ($^{252}Cf$) neutron source, which was positioned in the center of the neutron irradiation room. The neutron spectra of the calibration neutron fields were measured by a europium-activated lithium iodide scintillator in combination with KAERI's Bonner sphere system. When the shadow cone method was used, 10 single moderator-based survey meters exhibited a smaller calibration factor by as much as 3.1-9.3% than that of the semi-empirical method. This finding indicates that neutron survey meters underestimated the scattered neutrons and attenuated neutrons (i.e., the total scatter corrections). This underestimation of the calibration factor was attributed to the fact that single moderator-based survey meters have an under-ambient dose equivalent response in the thermal or thermal-dominant neutron field. As a result, when the shadow cone method is used for a single moderator-based survey meter, an additional correction and the International Organization for Standardization standard 8529-2 for room-scattered neutrons should be considered.

• Progress in Medical Physics
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• v.31 no.4
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• pp.135-144
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• 2020

Purpose: Gafchromic films for proton dosimetry are dependent on linear energy transfers (LETs), resulting in dose underestimation for high LETs. Despite efforts to resolve this problem for single-energy beams, there remains a need to do so for multi-energy beams. Here, a bimolecular reaction model was applied to correct the under-response of spread-out Bragg peaks (SOBPs). Methods: For depth-dose measurements, a Gafchromic EBT3 film was positioned in water perpendicular to the ground. The gantry was rotated at 15° to avoid disturbances in the beam path. A set of films was exposed to a uniformly scanned 112-MeV pristine proton beam with six different dose intensities, ranging from 0.373 to 4.865 Gy, at a 2-cm depth. Another set of films was irradiated with SOBPs with maximum energies of 110, 150, and 190 MeV having modulation widths of 5.39, 4.27, and 5.34 cm, respectively. The correction function was obtained using 150.8-MeV SOBP data. The LET of the SOBP was then analytically calculated. Finally, the model was validated for a uniform cubic dose distribution and compared with multilayered ionization chamber data. Results: The dose error in the plateau region was within 4% when normalized with the maximum dose. The discrepancy of the range was <1 mm for all measured energies. The highest errors occurred at 70 MeV owing to the steep gradient with the narrowest Bragg peak. Conclusions: With bimolecular model-based correction, an EBT3 film can be used to accurately verify the depth dose of scanned proton beams and could potentially be used to evaluate the depth-dose distribution for patient plans.

• The Journal of Industrial Distribution & Business
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• v.9 no.5
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• pp.63-72
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• 2018

Purpose - This work analyzes, in detail, the specification of vector error correction model (VECM) and thus examines the relationships and impact among seven economic variables for USA - balance on current account (BCA), index of stock (STOCK), gross domestic product (GDP), housing price indices (HOUSING), a measure of the money supply that includes total currency as well as large time deposits, institutional money market funds, short-term repurchase agreements and other larger liquid assets (M3), real rate of interest (IR_REAL) and household credits (LOAN). In particular, we search for the main explanatory variables that have an effect on stock and real estate market, respectively and investigate the causal and dynamic associations between them. Research design, data, and methodology - We perform the time series vector error correction model to infer the dynamic relationships among seven variables above. This work employs the conventional augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) unit root techniques to test for stationarity among seven variables under consideration, and Johansen cointegration test to specify the order or the number of cointegration relationship. Granger causality test is exploited to inspect for causal relationship and, at the same time, impulse response function and variance decomposition analysis are checked for both short-run and long-run association among the seven variables by EViews 9.0. The underlying model was analyzed by using 108 realizations from Q1 1990 to Q4 2016 for USA. Results - The results show that all the seven variables for USA have one unit root and they are cointegrated with at most five and three cointegrating equation for USA. The vector error correction model expresses a long-run relationship among variables. Both IR_REAL and M3 may influence real estate market, and GDP does stock market in USA. On the other hand, GDP, IR_REAL, M3, STOCK and LOAN may be considered as causal factors to affect real estate market. Conclusions - The findings indicate that both stock market and real estate market can be modelled as vector error correction specification for USA. In addition, we can detect causal relationships among variables and compare dynamic differences between countries in terms of stock market and real estate market.