• The KSFM Journal of Fluid Machinery
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• v.18 no.1
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• pp.11-19
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• 2015

Recently, the cross flow turbines attract more attention for their good performance over a large operating regime at off design point. This study employs a very low head cross flow turbine, which has open inlet duct and has barely been studied before, to investigate the performance of the cross flow turbine with air suction from the rear part of the runner. Unlike conventional cross flow turbines, a draft tube is attached to the outlet of runner to improve the turbine performance. Water level and pressure in the draft tube are monitored to investigate the influence of air suction. Torque at local blade passage of three parts of runner is examined in detail under the conditions of different air suction. Consequently, it is found that with proper air suction in the runner chamber, the water level in the draft tube gradually drops to Stage 2 of the runner and the efficiency of the turbine can be raised by 10%. Overall, the effect of air-layer on the performance of the turbine is considerable.

• Journal of Veterinary Science
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• v.24 no.4
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• pp.60.1-60.8
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• 2023

Background: Accurate diagnosis of diseases in animals is crucial for their treatment, and imaging evaluations such as radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) are important tools for this purpose. However, a cross-sectional anatomical atlas of normal skeletal and internal organs of long-tailed gorals (Naemorhedus caudatus) has not yet been prepared for diagnosing their diseases. Objectives: The objective of this study was to create an anatomical atlas of gorals using CT and MRI, which are imaging techniques that have not been extensively studied in this type of wild animal in Korea. Methods: The researchers used CT and MRI to create an anatomical atlas of gorals, and selected 37 cross-sections from the head, thoracic, lumbar, and sacrum parts of gorals to produce an average cross-sectional anatomy atlas. Results: This study successfully created an anatomical atlas of gorals using CT and MRI. Conclusions: The atlas provides valuable information for the diagnosis of diseases in gorals, which can improve their treatment and welfare. The study highlights the importance of developing cross-sectional anatomical atlases of gorals to diagnose and treat their diseases effectively.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.1006-1009
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• 2017

We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the ${\alpha}-{\alpha}$ system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the ${\alpha}-{\alpha}$ and ${\alpha}-n$ systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

• Journal of the Korean Wood Science and Technology
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• v.41 no.2
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• pp.141-148
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• 2013

The goal of this study was to find the optimum lamina size from red pine (Pinus densiflora) and Japanese cedar (Cryptomeria japonica) logs for the cross laminated timber (CLT) production. From visual inspection of the logs from two species, red pine log showed a larger knot and warp compared to the Japanese cedar. Different cross-sectional sizes of lamina ($110mm{\times}30mm$, $110mm{\times}40mm$, $110mm{\times}50mm$, $50mm{\times}30mm$, $30mm{\times}30mm$) from two species were analyzed for yield and grade. Regardless of the species, the optimized cross sectional size for maximizing the yield was $110mm{\times}30mm$. In grading for the different size laminas from Japanese cedar and red pine, a higher percentage of the first and second grade was found from the $110mm{\times}30mm$ lamina cut.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.215-218
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• 2001

Finite element models are constructed using the commercial code ANSYS for two most representative types of ultrasonic transducers, cMUTs and piezoelectric transducers. Calculation result shows the origin and level of cross talk between array elements in each transducer type For reduction of the cross talk level, the effects of various structural variations are Investigated for each transducer type. The results say that proper design of the coupling isolation structures between the transducing elements can significantly reduce the cross talk in ultrasonic transducers.

• Asian Journal of Innovation and Policy
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• v.8 no.1
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• pp.73-96
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• 2019

This study suggests a new approach for identifying core robot tech-nologies based on technological cross-impact. Specifically, the approach applies data mining techniques and multi-criteria decision-making methods to the co-classification information of registered patents on the robots. First, a cross-impact matrix is constructed with the confidence values by applying association rule mining (ARM) to the co-classification information of patents. Analytic network process (ANP) is applied to the co-classification frequency matrix for deriving weights of each robot technology. Then, a technique for order performance by similarity to ideal solution (TOPSIS) is employed to the derived cross-impact matrix and weights for identifying core robot technologies from the overall cross-impact perspective. It is expected that the proposed approach could help robot technology managers to formulate strategy and policy for technology planning of robot area.

• Proceedings of the KOSOMBE Conference
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• v.1990 no.11
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• pp.99-102
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• 1990

Cross correlation method was newly applied for the calculation of latency of evoked otoacoustic emission. The latency was calculated from the main peak of cross correlation function, which is one of possible definition of latency. The output was also compared with those of conventional autocorrelation method. The results show that cross correlation method has better performance than that of conventional method.

• Archives of Plastic Surgery
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• v.35 no.3
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• pp.248-254
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• 2008

Purpose: Human acellular dermal matrix(ADM) is widely used in the treatment of congenital anomalies and soft tissue deficiencies. But it is rapidly degraded in the body and does not provide satisfactory results. There is a need to improve collagen fiber stability through various methods and ultimately regulate the speed of degradation. Methods: The ADMs were added with various cross-linking agents called glutaraldehyde, dimethyl 3,3'-dithiobispropionimidate to produce cross-linked acellular dermal matrices. 1,4-butanediol diglycidyl ether solution was applied with a pH of 4.5 and 9.0, respectively. The stability of cross-linked dermal matrix was observed by measuring the shrinkage temperature and the degradation rates. The cross- and non-cross linked dermis were placed in the rat abdomen and obtained after 8, 12 and 16 weeks. Results: The shrinkage temperature significantly increased and the degradation rate significantly decreased, compared to the control(p<0.05). All of cross-linked dermises were observed grossly in 16 weeks, but most of non-cross linked dermis were absorbed in 8 weeks. Histologically, the control group ADM was found to have been infiltrated with fibroblasts and most of dermal stroma were transformed into the host collagen fibers. However, infiltration of fibroblasts in the experiment was insignificant and the original collagen structure was intact. Conclusion: Collagen cross-linking increases the structural stability and decreases degradation of acellular dermis. Therefore, decrease in body absorption and increase in duration can be expected.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.36-44
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• 2005

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank in recent years. Efficiency of push pull hood system is affected by various parameters, such as cross draft, vessel shapes, size of tanks surface, liquid temperature, and so on. Among these, velocity of cross draft might be one of the most influencing factor for determining the ventilation efficiency. To take account of the effect of cross draft velocities over 0.38m/s, a flow adjustment of ${\pm}$20% should be considered into the push and +20% into the pull flow system Although there are many studies about the efficiency evaluation of push pull hood system based on CFDs(Computational Fluid Dynamics) and experiments, there have been no reports regarding the influence of velocities and direction of cross-draft on push-pull hood efficiency. This study was conducted to investigate the influence of cross draft direction and velocities on the capture efficiency of the push-pull ventilation system. Smoke visualization method was used along with mock-up of push-pull hood systems to verify the ventilation efficiency by experiments. When the cross-draft blew from the same origins of the push flows, the efficiency of the system was in it's high value, but it was decreased significantly when the cross-draft came from the opposite side of push flows Moreover, the efficiency of the system dramatically decreased when the cross-draft of open surface tank was faster than 0.4m/s.

• Journal of Aerospace System Engineering
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• v.18 no.1
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• pp.21-28
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• 2024

In this paper, two prediction models based on deep neural network that could predict cross-sectional stiffness of a rotor blade were proposed. Herein, we employed structural and material information of cross-section. In the case of a prediction model that used material properties as the input of the network, it was designed to predict the cross-sectional stiffness by considering elastic modulus of each cross-sectional member. In the case of the prediction model that used structural information as a network input, it was designed to predict the cross-sectional stiffness by considering the location and thickness of cross-sectional members as network input. Both prediction models based on a deep neural network were realized using data obtained by cross-sectional analysis with KSAC2D (Konkuk section analysis code - two-dimensional).