• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.253-258
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• 2006

LDD175(4-choloro-7-trifluoromethyl-10H-benzo[4,5]furo[3,2-b]indole-l-carboxylic acid) is one of benzofuroindole derivatives that act as a potent $BK_{Ca}$ channel openers. In the process of testing LDD175 as a new drug candidate, an acute toxicity study was carried out in mice. The mice were administered LDD175 intraperitoneally at dose of 0.2, 1, 10, 50, 100, 200, 400, 800mg/kg and orally at dose of 10, 100, 400, 800mg/kg body weight. After administering LDD175, the vital organs such as the liver, kidney and spleen were carefully observed for any significant pathological features or differences from the norm over a l4-day period. LDD175 did not induce any short-term toxicity at doses less than 100mg/kg. A $LD_{50}$ of LDD175 was 2493mg/kg in male mice and 4908mg/kg in female mice. Weight reduction was observed at a dose of 800mg/kg in male, and 400 and 800mg/kg in female. The kidney weight decreased in females after an intraperitoneal injection of LDD175 high dose(>400mg/kg, i.p.), and the spleen weight increased in the male(800mg/kg, i.p.) and female(400mg/kg, i.p.) mice. Inspite of the change in organ weights, there were neither histopathological changes nor any gross morphological abnormalities detected in any organ. LDD175 did not produce significant changes in the general behavior at doses of <200mg/kg, but decreased locomotor activity was observed at an intraperitoneal dose of 400mg/kg. Its effects on the locomotor activity and activity on the rotarod were tested and compared with the effects of diazepam 5mg/kg. The decrement in the locomotor activity and the activity on the rotarod induced by LDD175 was less serious than it by diazepam.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.647-654
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• 2016

In the defense industry, national security takes priority over economic sense and this has translated into high cost and long-term research and development. However, the exponential growth of technology and rapid changes in the security situation in recent years have resulted in a call for the development of systems at a low cost within a short period of time. In order to implement a modularization strategy in the field of defense, the introduction of line replaceable units in OO systems needs to be prioritized. This study selects six criteria following a literature review and prioritizes 11 modules for OO systems using the project evaluation method, Grey Relational Analysis (GRA). Based on the GRA results, the grey relational grades were derived as 0.83, 0.81 and 0.80 for the M11 (Main board), M8 (EMI module), M3 (Single board computer) modules, respectively. The cost and time of development is expected to be reduced in accordance with the grey relational grade. The results of this research could be utilized for decision making on adopting modularization in similar system development or product improvement programs (PIPs).

• Journal of the Korean Arthroscopy Society
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• v.4 no.2
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• pp.111-116
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• 2000

Purpose : We reviewed the results of arthroscopic posterior cruciate ligament reconstruction using Achilles tendon allograft, and the efficacy of the surgical technique using gradual tibial tunneling and posterior transseptal technique. Materials and Methods : From september 1997 to September 1999, 8 patients with complete PCL injury were treated by arthroscopic PCL reconstruction using Achilles tendon allograft. Mean follow-up period was 21.7 months. Mean preoperative posterior laxity was 14mm. The clinical outcome was assessed by Telos stress test, Lysholm knee score and IKDC score. Result : There was no complication such as infection and neurovascular injury. Posterior translation using Telos device was less than 5mm in 6 cases$(75\%)$, and between 6 to 10mm in 2 cases$(25\%)$. The mean Lysholm knee score was 45 preoperatively and improved to 87 postoperatively. In IKDC system, 2 of 8 patients were group A and 6 were group B. Conclusion : Arthroscopic PCL reconstruction using achilles tendon allograft and posterior transseptal technique shows reliable stability, short operative time and minimizing donor site morbidity but needs more long term follow-up.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.2
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• pp.13-23
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• 2016

Many traffic centers are highly hesitant in employing existing Automatic Incident Detection Algorithms due to high false alarm rate, low detection rate, and enormous effort taken in maintaining algorithm parameters, together with complex algorithm structure and filtering/smoothing process. Concerns grow over the situation particularly in Freeway Incident Management Area This study proposes a new algorithm and introduces a novel concept, the Displaced Flow Index (DiFI) which is similar to a product of relative speed and relative occupancy for every execution period. The algorithm structure is very simple, also easy to understand with minimum parameters, and could use raw data without any additional pre-processing. To evaluate the performance of the DiFI algorithm, validation test on the algorithm has been conducted using detector data taken from Naebu Expressway in Seoul and following transferability tests with Gyeongbu Expressway detector data. Performance test has utilized many indices such as DR, FAR, MTTD (Mean Time To Detect), CR (Classification Rate), CI (Composite Index) and PI (Performance Index). It was found that the DR is up to 100%, the MTTD is a little over 1.0 minutes, and the FAR is as low as 2.99%. This newly designed algorithm seems promising and outperformed SAO and most popular AIDAs such as APID and DELOS, and showed the best performance in every category.

• Journal of Forest and Environmental Science
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• v.27 no.2
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• pp.101-111
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• 2011

The Returning Land for Farming to Forestry Project in China is similar to the 'The 10-year National Greening Project' of Korea, and is one of the great strategic policies that started in order to develop the people, resources and the environment by the central government of China. Using the ecosystem recovery as the slogan, The Returning Land for Farming to Forestry Project of China has a long history of 70 years, but the accomplishments has been insignificant when compared to the long history. The Returning Land for Farming to Forestry Project was not a trend due to the societal and economical issues of China, but with the increasing interest on the environmental protection in the late 1990s the extent of the ecosystem is gradually increasing. The most difficult, yet most important matter of the Returning Land for Farming to Forestry Project, is that it must consider the ecosystem with the economy. The farmers want financial gains in a short term, and the government aims is gaining cost-benefit over a long period which is why a rational the Returning Land for Farming to Forestry Project of the central government in China is most important. In order for the Returning Land for Farming to Forestry Project of China to develop further in the future, the standardization and distinction of the economic compensation policy is most urgent. Other than this, a new policy and the government interest on the livelihood of the farmers after the completion of the Returning Land for Farming to Forestry Project are needed, and there must be a clear and fair policy enactment environment so that the opinions of the farmers can influence the policy in the policy enactments.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.701-710
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• 2019

Objective: This study investigated the effect of different acute heat stress (HS) levels on chicken meat quality and ultra-structure. Methods: Chickens were randomly divided into 7 groups to receive different HS treatments: i) $36^{\circ}C$ for 1 h, ii) $36^{\circ}C$ for 2 h, iii) $38^{\circ}C$ for 1 h, iv) $38^{\circ}C$ for 2 h, v) $40^{\circ}C$ for 1 h, vi) $40^{\circ}C$ for 2 h, and vii) un-stressed control group ($25^{\circ}C$). Blood cortisol level, breasts initial temperature, color, pH, water holding capacity (WHC), protein solubility and ultra-structure were analyzed. Results: HS temperatures had significant effects on breast meat temperature, lightness ($L^*$), redness ($a^*$), cooking loss and protein solubility (p<0.05). The HS at $36^{\circ}C$ increased $L^*{_{24h}}$ value (p<0.01) and increased the cooking loss (p<0.05), but decreased $a^*{_{24h}}$ value (p<0.05). However, as the temperature increased to $38^{\circ}C$ and $40^{\circ}C$, all the values of $L^*{_{24h}}$, cooking loss and protein denaturation level decreased, and the differences disappeared compared to control group (p>0.05). Only the ultimate $pH_{24h}$ at $40^{\circ}C$ decreased compared to the control group (p<0.01). The pH in $36^{\circ}C$ group declined greater than other heat-stressed group in the first hour postmortem, which contributed breast muscle protein degeneration combining with high body temperature, and these variations reflected on poor meat quality parameters. The muscle fiber integrity level in group $40^{\circ}C$ was much better than those in $36^{\circ}C$ with the denatured position mainly focused on the interval of muscle fibers which probably contributes WHC and light reflection. Conclusion: HS at higher temperature (above $38^{\circ}C$) before slaughter did not always lead to more pale and lower WHC breast meat. Breast meat quality parameters had a regression trend as HS temperature raised from $36^{\circ}C$. The interval of muscle fibers at 24 h postmortem and greater pH decline rate with high body temperature in early postmortem period could be a reasonable explanation for the variation of meat quality parameters.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.4
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• pp.255-262
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• 2021

In this study, a jointless bridge that integrates the superstructure and abutment without installing an expansion joint was analyzed. An example of a jointless bridge that has been introduced in Korea since 2009. Owing to the short period of use and lack of experience in design, construction, and maintenance, there is insufficient information regarding the long-term behavior of jointless bridges. When analyzing numerous bridges, the numerical analysis model must maintain the numerical values used and ensure the convenience of model construction. In this study, sensitivity analysis was performed to select a numerical model for various types of jointless bridges using commercial finite element programs, MIDAS Civil and ABAQUS 2018. According to a solid element-based model, we analyzed the mean and maximum relative errors between structural models. Consequently, it was found that the beam element-based model exhibits a significantly small relative error in comparison to the shell element, where a relatively large error was recorded. Therefore, the optimal numerical analysis model, a practical model that maintains the similarity and precision of the displacement shape cause by relative error, was judged to be the most suitable for jointless bridges based on the shell element.

• Korean Journal of Remote Sensing
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• v.38 no.3
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• pp.225-236
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• 2022

Urbanization due to population growth and regional development can cause various environmental problems, such as the urban heat island phenomenon. A planned city is considered an appropriate study site to analyze changes in urban climate caused by rapid urbanization in a short-term period. In this study, changes in land cover and surface heat island phenomenon were analyzed according to the development plan in Sejong City from 2013 to 2020 using Landsat-8 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) satellite imagery. The surface temperature was calculated in consideration of the thermal infrared band value provided by the satellite image and the emissivity, and based on this the surface heat island effect intensity and Urban Thermal Field Variance Index (UTFVI) change analysis were performed. The level-2 land cover map provided by the Ministry of Environment was used to confirm the change in land cover as the development progressed and the difference in the surface heat island intensity by each land cover. As a result of the analysis, it was confirmed that the urbanized area increased by 15% and the vegetation decreased by more than 28%. Expansion and intensification of the heat island phenomenon due to urban development were observed, and it was confirmed that the ecological level of the area where the heat island phenomenon occurred was very low. Therefore, It can suggest the need for a policy to improve the residential environment according to the quantitative change of the thermal environment due to rapid urbanization.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.1
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• pp.57-69
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• 2023

In a situation where digital transformation using artificial intelligence is active around the world, the growth of domestic AI companies or AI industrial ecosystems is slow. Where a large amount of government funds related to AI are being invested to overcome the difficult economic situation, systematic research on the effect is insufficient. So, this study aimed to examine the policy effectiveness of the government artificial intelligence solution voucher support project for small and medium-sized enterprises (SMEs) using Propensity Score Matching (PSM) and Difference-in-Differences (DID) on the financial performance of beneficiary companies. For empirical analysis, PSM-DID analysis was performed using sales performance since 2019 for 461 companies with a history of voucher support among the AI SMEs data released by the National IT Industry Promotion Agency. As a result of the analysis, the beneficiary companies' asset growth, salary, and R&D expenses increased overall after government support, and no significant contribution could be confirmed in terms of profits. This study suggests that the voucher policy business directly contributed to the company's growth in the short term, but it requires a certain period of time to generate profits.

• The Journal of Korean Medicine
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• v.43 no.2
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• pp.61-74
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• 2022

Objectives: This study aimed to explore the short-term effects of bilateral masticatory training using an intraoral device on memory and concentration, which is an advanced form of Gochi, compared to the unilateral form with gum. Methods: Thirty young healthy participants (age, 16-30 years) were screened and randomly assigned to one of two sequences in a crossover design. The participants assigned to sequence A (n=15) performed bilateral mastication using an intraoral device with a total of 300 taps, followed by unilateral mastication using gum with the same number of repetitions and frequency, separated by a 7-day washout period. A reverse order was used for sequence B. The primary and secondary outcomes were the digit span test result and the symbol digit modality test and the word list recall results, respectively, which were conducted before and after each intervention. Results: Symbol digit modality test scores increased by 12.03±8.33 with bilateral mastication, which was significantly higher than that obtained with chewing gum (5.17 points;95% confidence interval: 0.99, 9.34; p<0.05). Changes in the digit span test and word list recall scores were not significantly different between the two groups. In the digit span test forward, symbol digit modality test, and word list recall test, bilateral mastication was not inferior to unilateral mastication in improving memory and concentration. Conclusions: Bilateral masticatory exercises using an intraoral device are not inferior to unilateral mastication with gum for improving memory in healthy young individuals. Further research is needed to determine the efficacy of bilateral masticatory training on cognitive function.