• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.401-409
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• 2021

This study aimed to estimate the photosynthetic capacity of tomato plants grown in a semi-closed greenhouse using temperature response models of plant photosynthesis by calculating the ribulose 1,5-bisphosphate carboxylase/oxygenase maximum carboxylation rate (V_cmax), maximum electron transport rate (J_max), thermal breakdown (high-temperature inhibition), and leaf respiration to predict the optimal conditions of the CO₂-controlled greenhouse, for maximizing the photosynthetic rate. Gas exchange measurements for the A-C_i curve response to CO₂ level with different light intensities {PAR (Photosynthetically Active Radiation) 200µmol·m^-2·s^-1 to 1500µmol·m^-2·s^-1} and leaf temperatures (20℃ to 35℃) were conducted with a portable infrared gas analyzer system. Arrhenius function, net CO₂ assimilation (A_n), thermal breakdown, and daylight leaf respiration (R_d) were also calculated using the modeling equation. Estimated J_max, A_n, Arrhenius function value, and thermal breakdown decreased in response to increased leaf temperature (> 30℃), and the optimum leaf temperature for the estimated J_max was 30℃. The CO₂ saturation point of the fifth leaf from the apical region was reached at 600ppm for 200 and 400µmol·m^-2·s^-1 of PAR, at 800ppm for 600 and 800µmol·m^-2·s^-1 of PAR, at 1000ppm for 1000µmol of PAR, and at 1500ppm for 1200 and 1500µmol·m^-2·s^-1 of PAR levels. The results suggest that the optimal conditions of CO₂ concentration can be determined, using the photosynthetic model equation, to improve the photosynthetic rates of fruit vegetables grown in greenhouses.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.3
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• pp.33-38
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• 2021

Recently, rollable and foldable displays are attracting great attention in the flexible display market due to their excellent form factor. To predict and prevent the mechanical failure of the display panels, it is essential to accurately understand the mechanical properties of brittle SiN_x thin films, which have been used as an insulating film in flexible displays. In this study, tensile properties of the ~130 nm- and ~320 nm-thick SiN_x thin films were successfully measured by coating a ~190 nm-thick organic nano-support-layer (PMMA, PS, P3HT) on the fragile SiN_x thin films and stretching the films as a bilayer state. Young's modulus values of the ~130 nm and ~320 nm SiN_x thin films fabricated through the controlled chamber pressure and deposition power (A: 1250 mTorr, 450 W/B: 1000 mTorr, 600 W/C: 750 mTorr, 700 W) were calculated as A: 76.6±3.5, B: 85.8±4.6, C: 117.4±6.5 GPa and A: 100.1±12.9, B: 117.9±9.7, C: 159.6 GPa, respectively. As a result, Young's modulus of ~320 nm SiN_x thin films fabricated through the same deposition condition increased compared to the ~130 nm SiN_x thin films. The tensile testing method using the organic nano-support-layer was effective in the precise measurement of the mechanical properties of the brittle thin films. The method developed in this study can contribute to the robust design of the rollable and foldable displays by enabling quantitative measurement of mechanical properties of fragile thin films for flexible displays.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.927-933
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• 2021

The purpose of this study was to compare and analyze the differences in scan time, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in the third lumbar vertebral region including the back fat, spinal cord, and cerebrospinal fluid using the mDixon, T2 TSE, and T2 spectral pre-saturation with inversion-recovery (SPIR) techniques. With the factors affecting the SNR fixed, the lumbar sagittal plane images of 30 adults were compared on mDixon, T2 TSE, and T2 SPIR imaging tests. The test times for mDixon, T2 TSE, and T2 SPIR were 115 seconds, 60 seconds, and 60 seconds, respectively. The mDixon T2 images showed higher SNR than the T2 TSE images at the third lumbar vertebral region (p<0.05), lower SNR in the back fat and cerebrospinal fluid (p<0.05) areas, and comparable SNR in the spinal cord (p>0.05). The CNR between the third lumbar vertebral area and back fat was higher in the mDixon T2 images, and the CNR of the cerebrospinal fluid and spinal cord images was higher in the T2 TSE images (p<0.05). The mDixon T2 FS images CNR was lower for the 3rd lumbar vertebral body region and back fat than the T2 SPIR images, and higher for the spinal cord and cerebrospinal fluid images (p<0.05). The CNR between the third lumbar body and back fat areas was higher in the mDixon T2 FS images (p<0.05), and there was no difference in the CNR in the images of the cerebrospinal fluid and the spinal cord (p>0.05). It is difficult to determine whether the mDixon technique is superior to the conventional T2 TSE and T2 SPIR techniques in terms of test time, SNR, and CNR. This study was confined to patients with simple lower back pain and was limited by controlled experimental conditions. Studies using clinically applied protocols are warranted in the future.

• 한국노년학
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• v.38 no.4
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• pp.1035-1055
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• 2018

The purpose of this study is to investigate the relationship between public care and family care. Public care for older adults began in 2008 with the implementation of the Long-Term Care insurance in South Korea. Although the expansion of public care has the purpose of reducing the care burden for the family, it is not easy to say whether the developments of public care system reduce the amount of family care for older family members. Theoretically, public care and family care are expected to have various relationships depending on the degree of the role and function(substitution, hierarchical compensatory, task specific, supplementation, complementarity). And literatures have showed inconsistent results depending on the country, data, and methods. In this study, we analyzed the relationship between two care types focusing on home care services for older persons. Analyses were based on data from the second(2008) to sixth(2016) waves of Korean Longitudinal Study of Ageing(KLoSA). To investigate elderly care dynamics in the households, we pooled the data for four changes between two periods(2008-2010, 2010-2012, 2012-2014, and 2014-2016). This study used an analytic sample of 262 older adults, who are aged 55 over and experienced public care at least one point of time. We used Fixed-Effects(FE) model to analyze the differences within the same individuals under the condition that time-invariant unobserved factors are controlled. This study distinguished the cases of entry into public care and other cases of exiting public care. The results showed that older people who are dependent on public care are less dependent on family care than before. In both entry and exit groups, negative relations were maintained, but in the entering stage of public care, the degree of negative relations was relatively small, whereas in the stage of maintaining or departing from public care, relatively negative relations were strong. At the beginning periods, even though public care increased, family care did not decrease significantly. On the other hand, at the time of ending public care and relying on family care, family care increased significantly. The results of this study show that the relationship between public care and family care is close to hierarchical compensatory model and varies according to the stage of caring transition. Also, it was found that the cases of transition from public care to family care have the biggest burden of elderly care than other groups.

• Anatomy & Biological Anthropology
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• v.31 no.4
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• pp.133-142
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• 2018

3D histology is a imaging system for the 3D structural information of cells or tissues. The synchrotron radiation propagation phase contrast micro-CT has been used in 3D imaging methods. However, the simple phase contrast micro-CT did not give sufficient micro-structural information when the specimen contains soft elements, as is the case with many biomedical tissue samples. The purpose of this study is to develop a new technique to enhance the phase contrast effect for soft tissue imaging. Experiments were performed at the imaging beam lines of Pohang Accelerator Laboratory (PAL). The biomedical tissue samples under frozen state was mounted on a computer-controlled precision stage and rotated in $0.18^{\circ}$ increments through $180^{\circ}$. An X-ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens(X5 or X20) before being captured with a digital CCD camera. 3-dimensional volume images of the specimen were obtained by applying a filtered back-projection algorithm to the projection images using a software package OCTOPUS. Surface reconstruction and volume segmentation and rendering were performed were performed using Amira software. In this study, We found that synchrotron phase contrast imaging of frozen tissue samples has higher contrast power for soft tissue than that of non-frozen samples. In conclusion, synchrotron radiation propagation phase contrast cryo-microCT imaging offers a promising tool for non-destructive high resolution 3D histology.

• International Area Studies Review
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• v.22 no.2
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• pp.163-186
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• 2018

The purpose of this study is to analyze the institutional conditions and problems for the transition to the North Korean economic system. As a research method, we first analyzed the legislative processes of 4th stage market reform policies (liberalization, privatization, privatization, and corporation) by major economic transition countries. And we found out the difference with North Korea. Based on this, it analyzed the process of institutionalization of North Korea's 4th stage economic reform policies (7.1 measures, comprehensive market policies, Currency reform, 6.28 policy). According to research, There are three important conditions that can not compare the changes of the North Korean market economy with those of the transition economies. First, the internal and external conditions and environment for the transition of the economic system and the role of the state and civil society are very different. Second, the means and objectives of the policy decision process and the implementation process are different. Third, it differs absolutely in terms of the nature and effectiveness of the nation's political and economic policies. Fourth, the priority, contents, and legislation process of economic policies for economic reform differ considerably from those of North Korea. Especially, when discussing the possibility of transition to the 'Chinese model', it is accompanied a considerable risk. It is because the purpose of market entry of control power in North Korea and their survival network are quite unique. In addition, China's domestic market size, population size, and type of control are quite different from North Korea. A necessary and sufficient condition for the transition of the North Korean economic system is the relaxation of physical control mechanisms and institutions in the market area. Next, it is necessary to make a legitimate institutionalization as well as an entire survey on the illegal ownership market. Based on this, it is necessary to gradually change the dependence of the domestic market on China to South Korea. In other words, this is a paradigm shift in the semi-controlled power exclusion, post-automation and domestic market.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.523-530
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• 2018

Purpose : The purpose of this study was to investigate the difference in the dynamic visual acuity between (DVA) the distance and near and the effect of change of accommodative stimulus on the dynamic visual acuity by the addition of the plus lens. Methods : The study involved 40 male and female adults ($22.84{\pm}2.43$ years old) with over 1.0 of visual acuity and without systemic disease or ocular disease. We compared the distance and near DVA and the change of DVA induced by the addition of the plus lens(+0.50D, +1.00D, +1.50D). Results : The distance DVA and near DVA are $78.86{\pm}19.46deg/sec$ and $76.90{\pm}18.05deg/sec$ respectively. The distance DVA was slightly higher(p=0.04). The higher the distance DVA, the higher the positive correlation with the near DVA and distance DVA, and distance DVA was higher in those who had higher the near DVA(r=0.95, p=0.00, Fig. 4). The near DVA according to the change of accommodative stimulus was $75.95{\pm}18.85deg/sec$ in full correction and the near DVA with +0.50D spherical power was $76.95{\pm}16.45$ but there was no statistically significant differences(p>0.05). However, the near DVA with +1.00D spherical power was $79.02{\pm}13.51deg/sec$ and it was slightly higher. Also, the near DVA with +1.50D spherical power was $84.28{\pm}18.96deg/sec$, there and it was statistically significant difference(p<0.05). Conclusion : There is no difference between distance and near DVA, but near DVA is also excellent if distance DVA is good. The DVA increases as added a plus lens for controlled accommodative stimulation changes.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.367-408
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• 2018

This study examines the features of globalization process in GM and Hyundai Motors, especially in the expansion into China auto market, through a joint venture(hereafter JV) research center. Due to the large scale market in China and the 50:50 JV, the two companies had to respond in some way to the Chinese government's request for localization of research and development functions, and their response affected the role of the JV research center. Even though the improvement in technological capability expected from the JV by the Chinese side did not appear well in the early stage in both JV, but relatively the Shanghai GM JV research center had a technological progress compared to the Beijing Hyundai JV research center. This paper explains the differences in the technical capabilities of the two JV research center, despite the same type of JV, as the difference between the status of the Chinese partner and the global strategy of the parent company. SAIC, a Chinese partner in Shanghai GM as a top-tier company, not only has been strongly demanding technology transfer from GM since the beginning of the JV, but has also made efforts to improve its own technical capabilities. Meanwhile, BAIC, a Chines partner in Beijing Hyundai as a mid-tier company, has not been strongly demanding technology transfer and lacked its own research base. Regarding the parent company's global strategy, although both companies controlled the core areas of research and development by their parent companies, GM actively considered using the Chinese RV to develop Chinese and emerging country vehicles. On the other hand, Hyundai Motors responded to the localization demand of the Chinese government while paying more attention to preventing technology leakage through its independent research center in China. The above discussion shows that the process of globalization of a company is a political process in which the global strategy of the parent company and the demands of the stakeholders surrounding the subsidiary are collided and compromised, rather than a process in which the harmony and cooperation between the parent company and its subsidiaries are smoothly achieved as the parent company's policies are unilaterally implemented.

• Cross-Cultural Studies
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• v.52
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• pp.277-312
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• 2018

First-order cybernetics during the 1940s and 1950s aimed for control of an observed system, while second-order cybernetics during the mid-1970s aspired to address the mechanism of an observing system. The former pursues an objective, subjectless, approach to a system, whereas the latter prefers a subjective, personal approach to a system. Second-order observation must be noted since a human observer is a living system that has its unique cognition. Maturana and Varela place the autopoiesis of this biological system at the core of second-order cybernetics. They contend that an autpoietic system maintains, transforms and produces itself. Technoscientific recreation of biological autopoiesis opens up to a new step in cybernetics: what I describe as third-order cybernetics. The formation of technoscientific autopoiesis overlaps with the Fourth Industrial Revolution or what Erik Brynjolfsson and Andrew McAfee call the Second Machine Age. It leads to a radical shift from human centrism to posthumanity whereby humanity is mechanized, and machinery is biologized. In two versions of the novel Demon Seed, American novelist Dean Koontz explores the significance of technoscientific autopoiesis. The 1973 version dramatizes two kinds of observers: the technophobic human observer and the technology-friendly machine observer Proteus. As the story concludes, the former dominates the latter with the result that an anthropocentric position still works. The 1997 version, however, reveals the victory of the techno-friendly narrator Proteus over the anthropocentric narrator. Losing his narrational position, the technophobic human narrator of the story disappears. In the 1997 version, Proteus becomes the subject of desire in luring divorcee Susan. He longs to flaunt his male egomaniac. His achievement of male identity is a sign of technological autopoiesis characteristic of third-order cybernetics. To display self-producing capabilities integral to the autonomy of machinery, Koontz's novel demonstrates that Proteus manipulates Susan's egg to produce a human-machine mixture. Koontz's demon child, problematically enough, implicates the future of eugenics in an era of technological autopoiesis. Proteus creates a crossbreed of humanity and machinery to engineer a perfect body and mind. He fixes incurable or intractable diseases through genetic modifications. Proteus transfers a vast amount of digital information to his offspring's brain, which enables the demon child to achieve state-of-the-art intelligence. His technological editing of human genes and consciousness leads to digital standardization through unanimous spread of the best qualities of humanity. He gathers distinguished human genes and mental status much like collecting luxury brands. Accordingly, Proteus's child-making project ultimately moves towards technologically-controlled eugenics. Pointedly, it disturbs the classical ideal of liberal humanism celebrating a human being as the master of his or her nature.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.603-617
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• 2018

This study surveyed the diversity and community characteristics of benthic macroinvertebrates and freshwater fish, which are the main animal classifications in a hydro ecosystem, from May to September 2017 in the western plains of the Demilitarized Zone (DMZ). The results showed a total of 125 species of benthic macroinvertebrates belonging to 66 families, 19 orders, and four phyla in the streams and wetlands. Among benthic macroinvertebrates, Coleoptera (27 spp.: 21.60%) was the largest group in terms of species richness followed by Odonata (26 spp.: 20.80%), non-Insecta (22 spp.: 17.60%), and Hemiptera (11 spp.: 8.80%) occupying in the lentic area. Of the feeding function groups (FFGs), predators (51 spp.: 56.67%) showed a relatively larger presence, indicating the dominance of hygrophilous invertebrates that usually inhabit the freshwater wetlands or ponds. Of the habitat oriented groups (HOGs), climbers (33 spp.: 24.44%) and burrowers (17 spp.: 12.59%) were the dominant groups. This observation is typical in a slow flowing habitat and can lead to the disturbance of the ecosystem due to cannibalism among predators. Cannibalism can be caused by stress induced by various population and environmental factors. For the ecosystem services benchmark (ESB) value, site 13 appeared to be the highest with 82 marks while other sites showed relatively lower rates and indices (III water quality class with ${\alpha}$-mesosaprobic). The analysis result of stability factors showed that almost all sites were evaluated to be the I characteristic group with high resilience and resistance or the III characteristic group that was sensitive to environmental disturbance and formed uneven and unstable communities. Of the freshwater fishes, 46 species (3,405 individuals) belonging to 39 families and 18 orders were identified in all the investigated sites. Among them, Cyprinidae (30 spp.: 65.2%) was the largest group, and Zacco koreanus was identified as the dominant species (728 individuals, 21.4%). The survey of freshwater fish communities found both stable communities (sites 7 and 13) with low dominant index (0.39) and high diversity index (2.29) and unstable communities (sites 2, 3, 8, and 10) in opposite tendency. This survey found five Korean endemic species, 17 species belonging to the export controlled species, two endangered species level II (Lethocerus deyrollei and Cybister chinensis), and rare species (Dytiscus marginalis czerskii) among benthic macroinvertebrates. The survey also found an invasive species, Ampullarius insularus, which was distributed throughout the whole area and thus can continuously disturb the ecosystem in the western plain area in the DMZ. Of freshwater fish, one natural monument (Hemibarbus mylodon) and three endangered species level II (Acheilognathus signifer, Gobiobotia macrocephalus, and G. brevibarba) were observed. The survey also found four introduced species (Pomacea canaliculate, Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides) in the western DMZ area, indicating the need for the protection and conservation measures.