• International journal of advanced smart convergence
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• v.10 no.4
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• pp.241-255
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• 2021

The human auricle is the first part to receive sound from the outside. In this part, the frequency range of human recognizable form is divided and organized. In this study, we propose modeling by applying a single sound source to the surface of the human auricle. This means that when the sound pressure of a low frequency (low frequency) sound enters the pinna, the impedance felt at the tip of a part of the non-linear surface of the pinna is mainly due to the tensile force at the end of the part of the non-linear surface of the pinna. By expressing the situation of moving at a very small speed, the characteristic impedance of the pinna was confirmed to be negative infinity, and it was also confirmed that the speed at the tip of a part of the non-linear surface of the pinna was 0 in the anti-resonance state. It was found that the wave propagation phenomenon that determines the characteristics of the filter is determined by how large the wavelength, kL, is compared to the length of the tip of a part of the non-straight surface of the pinna. Humans first receive sounds from outside through their ears. The auricle is non-linear and has a curved shape, and it is known that it analyzes frequencies while receiving external sounds. The human ear has an audible frequency range of 20Hz - 20,000Hz. Through the study, we applied the characteristics of the notch filter to hypothesize that the human audible frequency range is separated from the auricle, and applied filter theory to analyze it, and as a result, meaningful results were obtained. The curved part and the inner part of the auricle function as a trumpet, collecting sounds, and at the same time amplifying the weak sound of a specific band. The point was found and the shape of the envelope detected in the auricle was found. Selectivity for selecting sounds coming from the outside is the formula of the pinna that implements the function of Q. The function of distinguishing human-recognizable sound from the pinna from low to high through frequency analysis is performed in the pinna, and the 2-3kHz area, where human hearing threshold is the most sensitive, is also the acoustic impedance of the most recessed area of the pinna. It can be seen that starting from.

• Journal of Microbiology and Biotechnology
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• v.31 no.3
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• pp.380-386
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• 2021

The coronavirus disease 2019 (COVID-19) pandemic has become a public health emergency of global concern. In China, traditional Chinese medicine has been widely administered to COVID-19 patients without sufficient evidence. To evaluate the efficacy of Shenhuang Granule (SHG) for treating critically ill patients with COVID-19, we included in this study 118 patients who were admitted to the ICU of Tongji Hospital between January 28, 2020 and March 28, 2020. Among these patients, 33 (27.9%) received standard care plus SHG (treatment group) and 85 (72.1%) received standard care alone (control group). Enrolled patients had a median (IQR) age of 68 (57-75) years, and most (79 [67.1%]) were men. At end point of this study, 83 (70.3%) had died in ICU, 29 (24.5%) had been discharged from ICU, and 6 patients (5.2%) were still in ICU. Compared with control group, mortality was significantly lower in treatment group (45.4% vs. 80%, p < .001). Patients in treatment group were less likely to develop acute respiratory distress syndrome (ARDS) (12 [36.3%] vs. 54 [63.5%], p = 0.012) and cardiac injury (5 [15.1%] vs. 32 [37.6%], p = 0.026), and less likely to receive mechanical ventilation (22 [66.7%] vs. 72 [84.7%], p = 0.028) than those in control group. The median time from ICU admission to discharge was shorter in treatment group (32 [20-73] days vs. 76 [63-79] days, p = 0.0074). These findings suggest that SHG treatment as a complementary therapy might be effective for critically ill adults with COVID-19 and warrant further clinical trials.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.507-514
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• 2010

Peanut(Arachis hypogaea L.) is one of the major oilseed crops. The peanut oil consists of palmitic, oleic and linoleic acids, which are present at levels of 10%, 36-67% and 15-43%, respectively. High oleate mutant of peanut F435 contains 80% oleate and as little as 2% linoleate in seed oil. Previous study indicated that delta 12 fatty acid desaturase is a major enzyme controlling the oleate content in seeds of oilseed crops. F435 sequence alignment of their coding regions disclosed that an extra A(adenine) was inserted at the position +2,823 bp of delta 12 fatty acid desaturase gene. This study was to develop molecular marker (SNP marker) co-segregating with the high oleate trait. Chopyeong ${\times}$ F435 $F_2$ 41 population were investigated using molecular marker and fatty acid assay (NIR and gas chromatography). Finally, this marker segregates Chopyeong type 26 lines, heterotype 9 lines and F435 type 6 lines. These results in our study suggested that SNP marker conform fatty acid assay.

• Geomechanics and Engineering
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• v.17 no.4
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• pp.333-342
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• 2019

Geological dynamic hazards during coal mining can be caused by the failure of a composite system consisting of roof rock and coal layers, subject to different loading rates due to different advancing velocities in the working face. In this paper, the uniaxial compression test simulations on the composite rock-coal layers were performed using $PFC^{2D}$ software and especially the effects of loading rate on the stress-strain behavior, strength characteristics and crack nucleation, propagation and coalescence in a composite layer were analyzed. In addition, considering the composite layer, the mechanisms for the advanced bore decompression in coal to prevent the geological dynamic hazards at a rapid advancing velocity of working face were explored. The uniaxial compressive strength and peak strain are found to increase with the increase of loading rate. After post-peak point, the stress-strain curve shows a steep stepped drop at a low loading rate, while the stress-strain curve exhibits a slowly progressive decrease at a high loading rate. The cracking mainly occurs within coal, and no apparent cracking is observed for rock. While at a high loading rate, the rock near the bedding plane is damaged by rapid crack propagation in coal. The cracking pattern is not a single shear zone, but exhibits as two simultaneously propagating shear zones in a "X" shape. Following this, the coal breaks into many pieces and the fragment size and number increase with loading rate. Whereas a low loading rate promotes the development of tensile crack, the failure pattern shows a V-shaped hybrid shear and tensile failure. The shear failure becomes dominant with an increasing loading rate. Meanwhile, with the increase of loading rate, the width of the main shear failure zone increases. Moreover, the advanced bore decompression changes the physical property and energy accumulation conditions of the composite layer, which increases the strain energy dissipation, and the occurrence possibility of geological dynamic hazards is reduced at a rapid advancing velocity of working face.

• Journal of Environmental Impact Assessment
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• v.28 no.2
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• pp.141-151
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• 2019

Korea has passed the Act on the Integrated Control of Pollutant-Discharging Facilities in 2015, and the integrated environmental management under the BAT standard is underway. To summarize the nature of integrated environmental management, it is the regulation by the integration of the management of the multi-pollutant source and the technical standard of BATs. In general, in environmental economics, regulation-based on technical standards are known to be inefficient. This paper attempts to evaluate the efficiency of BAT standards from an economic point of view. A simple multi-pollutant model demonstrates that the inefficiency of the environmental tax with imperfect information in a single pollutant situation is amplified under multi-pollutant conditions. The simultaneous introduction of BAT and IPPC can be partially explained by this logic. It is also highlighted by the strengthening of BAT standards by EU, as a countermeasure to the potential deterioration of air quality caused by the change of effective environmental taxes accompanying the fuel and emission price changes.

• Design & Manufacturing
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• v.13 no.2
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• pp.30-36
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• 2019

Traditional cell culture(2-dimensional) is the method that provide a nutrient and environment on a flat surface to cultivate cells into a single layer. Since the cell characteristics of 2D culture method is different from the characteristics of the cells cultured in the body, attempts to cultivate the cells in an environment similar to the body environment are actively proceeding in the industry, academy, and research institutes. In this study, we will develop a technology to fabricate micro-structures capable of culturing cells on surfaces with various curvatures, surface shapes, and characteristics. In order to fabricate the hemispheric plastic structure(thickness $50{\mu}m$), plastic preform mold (hereinafter as "preform mold") corresponding to the hemisphere was first prepared by injection molding in order to fabricate a two - layer structure to be combined with a flat plastic film. Then, thermoplastic polymer dissolved in an organic solvent was solidified on a preform mold. As a preliminary study, we proposed injection molding conditions that can minimize X/Y/Z axis deflection value. The effects of the following conditions on the preform mold were analyzed through injection molding CAE, [(1) coolant inlet temperature, (2) injection time, (3) packing pressure, (4) volume-pressure (V/P). As a result, the injection molding process conditions (cooling water inlet temperature, injection time, holding pressure condition (V / P conversion point and holding pressure size)) which can minimize the deformation amount of the preform mold were derived through CAE without applying the experimental design method. Also, the derived injection molding process conditions were applied during actual injection molding and the degree of deformation of the formed preform mold was compared with the analysis results. It is expected that plastic film having various shapes in addition to hemispherical shape using the preform mold produced through this study will be useful for the molding preform molding technology and cast molding technology.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.39-44
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• 2019

Radiation safety management is being considered very important since radioactive isotopes such as Co-60 and Ir-192 are widely used in fields such as non-destructive test(NDT). In this study, the applicability of Mercury(II) Iodide($HgI_2$) source for tracing system was evaluated. To make sure the unit cell sensor's reliability, we evaluated the electrical properties of the sensor made with $HgI_2$, and then position dependence of the sensor was analyzed and compared with the dose distribution from the planning system. As a result of the evaluation, high reliability of the sensor was shown through the linearity of R-sq > 0.990 and reproducibility of CV < 0.015. In the position dependence evaluation, the maximum value was measured at the isocenter of the sensor and gradually decreased according to the distance. However, the dose distribution data from the planning system was turned out that has difference with that of the sensor up to 30%. This seems to come from the difference between single-point measuring based planning system and area measuring based sensor.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.2
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• pp.309-316
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• 2019

In this paper, a low-jitter delay-locked loop that compensates for local clock skew is presented. The proposed DLL consists of a phase splitter, a phase detector(PD), a charge pump, a bias generator, a voltage-controlled delay line(VCDL), and a level converter. The VCDL uses self-biased delay cells using current mode logic(CML) to have insensitive characteristics to temperature and supply noises. The phase splitter generates two reference clocks which are used as the differential inputs of the VCDL. The PD uses the only single clock from the phase splitter because the PD in the proposed circuit uses CMOS logic that consumes less power compared to CML. Therefore, the output of the VCDL is also converted to the rail-to-rail signal by the level converter for the PD as well as the local clock distribution circuit. The proposed circuit has been designed with a $0.13-{\mu}m$ CMOS process. A global CLK with a frequency of 1-GHz is externally applied to the circuit. As a result, after about 19 cycles, the proposed DLL is locked at a point that the control voltage is 597.83mV with the jitter of 1.05ps.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.363-373
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• 2018

In today's diversified society, it is hard to know which building style represents the architectural style of the time. The simplicity found in monolithic-style buildings forms a symmetrical point with fairly complex structure, and its value can be acknowledged. This study analyzes buildings made of insulating lightweight aggregate concrete in the early 21st century, defines the concept of monolithic expression, and examines how these characteristics are expressed in the space, forms, and structural methods in construction. Unlike a multi-layered exterior wall system, which features multiple layers composed of a variety of materials, the exterior walls built with insulating lightweight aggregate concrete comes in a lump form with a mold form that is tightly filled with concrete as a single material and is monolithic. This is attributed to the creation of spaces characterized by the homogeneity of inner and outer spaces with the use of the same material, continuity of the surface as solidity, spatial characteristics of the stereotomic construction, expression of materiality with the use of exposed concrete, and the contrast of the lump and the space. This not only reveals formal characteristics that expose a discourse about monolithic architecture in contemporary architecture but also provide an opportunity to extend the range of discussion to structures and materials and even to their effects on space.

• Journal of Korea Water Resources Association
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• v.54 no.5
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• pp.301-309
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• 2021

In this study, we tried to improve the performance of the existing U-net-based deep learning rainfall prediction model, which can weaken the meaning of time series order. For this, ConvLSTM2D U-Net structure model considering temporal consistency of data was applied, and we evaluated accuracy of the ConvLSTM2D U-Net model using a RainNet model and an extrapolation-based advection model. In addition, we tried to improve the uncertainty in the model training process by performing learning not only with a single model but also with 10 ensemble models. The trained neural network rainfall prediction model was optimized to generate 10-minute advance prediction data using four consecutive data of the past 30 minutes from the present. The results of deep learning rainfall prediction models are difficult to identify schematically distinct differences, but with ConvLSTM2D U-Net, the magnitude of the prediction error is the smallest and the location of rainfall is relatively accurate. In particular, the ensemble ConvLSTM2D U-Net showed high CSI, low MAE, and a narrow error range, and predicted rainfall more accurately and stable prediction performance than other models. However, the prediction performance for a specific point was very low compared to the prediction performance for the entire area, and the deep learning rainfall prediction model also had limitations. Through this study, it was confirmed that the ConvLSTM2D U-Net neural network structure to account for the change of time could increase the prediction accuracy, but there is still a limitation of the convolution deep neural network model due to spatial smoothing in the strong rainfall region or detailed rainfall prediction.