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A Study on the Influencing Factors of the Sales and Surplus Companies of the Townbuses in Seoul (서울시 마을버스 매출액 및 흑자업체의 영향요인에 대한 연구)

  • Jang, Jae-min;Shin, Sung-il;YI, Yong-ju
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.4
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    • pp.115-124
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    • 2022
  • Unlike the semi-public system of city buses, Seoul's townbus are operated on a private operating system, which is poor condition to the changes in the environment. Sales decreased due to a decrease in the number of passengers due to COVID-19 and a demand for conversion due to the advent of competitive transportation methods, and the financial support of Seoul Metropolitan Government is continuously increasing. In this study, to analyze the characteristics of townbus operated by a private operating system, the townbus sales and surplus companies were analyzed by what factors were affected. For the analysis data, townbus financial statements of Seoul in 2018 were used, and townbus sales and surplus companies were applied as dependent variables, and townbus operation system, satisfaction survey, humanities and social variables, and subway and public bicycle characteristics were applied as independent variables. As a result of the analysis, the sales is affected by operating hours per vehicle, in-vehicle safety, the number of households, the number of elderly people, and public bicycle variables, and surplus companies are affected by in-vehicle safety, reliability, and public bicycle variables. In particular, public bicycles, a competitive means of transportation, had an impact on industry sales, and the townbus business environment is expected to become more difficult as time goes by. The industry is seeking self-rescue measures, and Seoul is required to strengthen financial support so that townbus can operate stably.

Analysis of Occupational Therapy Intervention Research for Improving Memory: Focus on Single-Subject Research Design in Korean Academic Journals (기억력 향상을 위한 작업치료 중재 연구 분석: 국내 단일대상연구 중심으로)

  • Jung, Yu-Jin;Choi, Yoo-Im
    • Therapeutic Science for Rehabilitation
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    • v.10 no.4
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    • pp.39-52
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    • 2021
  • Objective : This study aimed to identify the characteristics and analyze the quality of studies on memory improvement using a single-subject research design. Methods : Six studies were selected through the Research Information Sharing Service (RISS), Korean Studies Information Service System (KISS), and National Digital Science Library (NDSL). Keywords were memory training, stroke, early dementia, mild cognitive impairment, and single-subject research design. The characteristics and quality levels were analyzed between January 2011 and October 2020. Results : Regarding the quality level, the middle level (7-10 points) was 66.7% of the four articles, and the high level (11-14 points) was 33.3% of the two articles. Reversal designs were used in all studies. Independent variables were errorless learning, smartphone application, cognitive training system (CoTras), spaced retrieval training (SRT) with errorless learning, spaced retrieval training, and iPad applications. The dependent variables included memory, attention, electroencephalogram, instrumental activities of daily living, depression etc., which increased after the intervention. The total session, study period, and intervention time were varied. Conclusion : In single-subject research design related to memory training, occupational therapy intervention was confirmed as an effective method for improving memory and attention. The quality level of single-subject research design was moderate or higher, and high-quality level of studies should be conducted by additional design to increase the validity in the future.

A Study on the Verification of Physiological Activities of Ternstroemia kwangtungensis Merr. Extract (베트남 후피향 추출물의 생리활성 검증에 대한 연구)

  • Jung, Su-Hyun;Yeom, Hyeon-Ji;Oh, Min-Jeong;Lee, Jin-Young
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.48 no.1
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    • pp.39-46
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    • 2022
  • In this study, we tried to find out the value of using Vietnamese Ternstroemia kwangtungensis Merr. (TK) extracts as a functional material. As a result of measuring the level of Nrf2 expression of TK, 50% ethanol extract TK leaf showed the highest activity at a concentration of 200 ㎍/mL. In order to confirm the stability of the extract over time at room temperature, UPLC was performed, and stability was maintained because the patterns of the UV spectrum pattern were the same. In order to confirm the antioxidant efficacy of TK, the activity increased as the concentration increased as a result of measuring electron donating and ABTS+ radical scavenging ability. At 1,000 ㎍/mL, they showed effects of 94.6% and 90.8%, respectively. As a result of measuring the tyrosinase inhibitory activity showed an inhibitory ability of 24.4% at a concentration of 1,000 ㎍/mL. In addition, as a result of examining the elastase inhibitory activity of the extract was increased in a concentration-dependent manner, and it was confirmed that the inhibitory activity was 42.7% at 1,000 ㎍/mL. From these results, it was confirmed that the TK extract was valuable as a natural material for cosmetics.

The Economic Impact of the May 18 Democratic Uprising on the Regional Economy: A Synthetic Control Method (SCM) approach (5·18민주화운동이 지역경제에 미친 경제적 영향 분석: 통제집단합성법(SCM)을 이용한 접근)

  • Ryu, Deockhyun;Seo, Dongkyu
    • Analyses & Alternatives
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    • v.6 no.2
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    • pp.155-183
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    • 2022
  • The purpose of this study is to econometrically analyze the negative impact of the May 18 Democratic Uprising on the Gwangju/Jeonnam regionional economy using the Synthetic Control Method (SCM). The SCM SCM is a methodology similar to the difference-in-difference(DID) method of microeconometrics. It is applied to macroeconomic variables such as country, region, etc. to estimate the causal relationship between specific events and the dependent variable. In this study, as of 1980, local tax revenue data of metropolitan local governments were used as a proxy variable for the economy of the region, and the impact of the May 18 Democratic Uprising on the economy of Gwangju/Jeonnam region was analyzed through various socio-economic indicators. In this study, data were used to analyze from 1971 to 2000, and as a result of empirical analysis, local tax revenues in Gwangju/Jeonnam area were less collected than normal routes up to 17%. In addition, the significance of this analysis was confirmed through in-time placebo effect analysis and in-space placebo effect analysis, which are methods of analyzing the robustness of the control group synthesis method.

The Application of NIRS for Soil Analysis on Organic Matter Fractions, Ash and Mechanical Texture

  • Hsu, Hua;Tsai, Chii-Guary;Recinos-Diaz, Guillermo;Brown, John
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1263-1263
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    • 2001
  • The amounts of organic matter present in soil and the rate of soil organic matter (SOM) turnover are influenced by agricultural management practice, such as rotation, tillage, forage plow down direct seeding and manure application. The amount of nutrients released from SOM is highly dependent upon the state of the organic matter. If it contains a large proportion of light fractions (low-density) more nutrients will be available to the glowing crops. However, if it contains mostly heavy fractions (high-density) that are difficult to breakdown, then lesser amounts of nutrients will be available. The state of the SOM and subsequent release of nutrients into the soil can be predicted by NIRS as long as a robust regression equation is developed. The NIRS method is known for its rapidity, convenience, simplicity, accuracy and ability to analyze many constituents at the same time. Our hypothesis is that the NIRS technique allows researchers to investigate fully and in more detail each field for the status of SOM, available moisture and other soil properties in Alberta soils for precision farming in the near future. One hundred thirty one (131) Alberta soils with various levels (low 2-6%, medium 6-10%, and high >10%) of organic matter content and most of dry land soils, including some irrigated soils from Southern Alberta, under various management practices were collected throughout Northern, Central and Southern Alberta. Two depths (0- 15 cm and 15-30 cm) of soils from Northern Alberta were also collected. These air-dried soil samples were ground through 2 mm sieve and scanned using Foss NIR System 6500 with transport module and natural product cell. With particle size above 150 microns only, the “Ludox” method (Meijboom, Hassink and van Noorwijk, Soil Biol. Biochem.27: 1109-1111, 1995) which uses stable silica, was used to fractionate SOM into light, medium and heavy fractions with densities of <1.13, 1.13-1.37 and >1.37 respectively, The SOM fraction with the particle size below 150 microns was discarded because practically, this fraction with very fine particles can't be further separated by wet sieving based on density. Total organic matter content, mechanical texture, ash after 375$^{\circ}C$, and dry matter (DM) were also determined by “standard” soil analysis methods. The NIRS regression equations were developed using Infra-Soft-International (ISI) software, version 3.11.

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Formulation Optimization Study of Carvedilol and Ivabradine Fixed-dose Combination Tablet Using Full-factorial Design (완전요인배치법을 이용한 carvedilol 및 ivabradine 이층정 복합제 내 carvedilol 속방층 제형 최적화 연구)

  • Yu Lim Song;Kang Min Kim
    • Journal of Life Science
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    • v.33 no.3
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    • pp.268-276
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    • 2023
  • This study was conducted to optimize the formulation conditions of the immediate-release layer of carvedilol in the development of a two-layer tablet formulation for carvedilol and ivabradine. Using a 24+3 full-factorial design of experiments, excipients (microcrystalline cellulose, citric acid, and crospovidone) of the carvedilol immediate-release layer (wet granulation part) and process parameters for the tablet compression process (main compression) were optimized, and seven types of each dependent variable (assay, content uniformity, hardness, friability, disintegration, and dissolution [pH 1.2 and 6.8]) were evaluated using design expert software. The analysis of variance results confirmed that the main compression has a significant effect on hardness, friability, and disintegration time and that microcrystalline cellulose has a major effect on friability and dissolution. In addition, it was confirmed that citric acid has a significant effect on friability. Crospovidone affects friability and dissolution. According to the design space from the design of the experiment results, the optimized range is microcrystalline cellulose (~18.0-32.0 mg), citric acid (~0.5-12 mg), and main compression (~615-837 kgf). Consequently, this study confirmed the availability of manufacturing the carvedilol immediate-release layer in which all risk factors evaluated in the initial risk assessment are removed.

Affecting Factors of Lung Disease and Classification of Exposure Rating of Applicants for Injuries from Humidifier Disinfectants (가습기살균제 피해신청자들의 노출등급 분류 및 폐질환 발생 영향요인 분석)

  • Gihong, Min;Junghyun, Shin;Eun-Kyung, Jo;Dayoung, Jeong;Jiyoon, Ryu;Dongjun, Kim;Jaemin, Woo;Sungho, Bae;Jihun, Shin;Seula, Lee;Yoon-Hyeong, Choi;Wonho, Yang
    • Journal of Environmental Health Sciences
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    • v.48 no.6
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    • pp.324-330
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    • 2022
  • Background: Lung injuries due to exposure to humidifier disinfectants (HDs) were reported in 2011 in South Korea. As a result of the government's epidemiological investigation and toxicity test study, it was found that HDs caused health damage such as lung disease. Objectives: The purpose of this study was to classify HD exposure ratings and analyze the affecting factors that could identify the relationship with lung disease. Methods: Exposure assessment for HDs was conducted using a questionnaire during face-to-face interviews with the applicants. Ratings of high exposure (Class 1) and low exposure (Class 2) were cross-tabulated with clinical ratings (acceptable and unacceptable). Logistic regression analysis was carried out by setting the clinical rating of lung disease as a dependent variable and the socio-demographic and exposure characteristics obtained through the questionnaire as independent variables. Results: The concentration in air of polyhexamethylene guanidine (PHMG) was 71.96±107.47 ㎍/m3, and the exposure concentration was 15.21±23.28 ㎍/m3 . The exposure rating was overestimated with 97.1% of affected subjects having high exposure using margin of exposure (MOE), but only 9.9% matching the clinical class. In the overestimated group, it could be explained by the fact that the exposure time was long and the subjects had already recovered from damage symptoms. As a result of logistic regression analysis, ten variables were found to be significant influencing factors. Conclusions: A new exposure rating could be calculated based on the MOE, and factors affecting lung disease could be estimated through comparative evaluation with the clinical rating.

The Algorithm for an Energy-efficient Particle Sensor Applied LEACH Routing Protocol in Wireless Sensor Networks (무선센서네트워크에서 LEACH 라우팅 프로토콜을 적용한 파티클 센서의 에너지 효율적인 알고리즘)

  • Hong, Sung-Hwa;Kim, Hoon-Ki
    • Journal of the Korea Society for Simulation
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    • v.18 no.3
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    • pp.13-21
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    • 2009
  • The sensor nodes that form a wireless sensor network must perform both routing and sensing roles, since each sensor node always has a regular energy drain. The majority of sensors being used in wireless sensor networks are either unmanned or operated in environments that make them difficult for humans to approach. Furthermore, since many wireless sensor networks contain large numbers of sensors, thus requiring the sensor nodes to be small in size and cheap in price, the amount of power that can be supplied to the nodes and their data processing capacity are both limited. In this paper, we proposes the WSN(Wireless Sensor Network) algorithm which is applied sensor node that has low power consumption and efficiency measurement. Moreover, the efficiency routing protocol is proposed in this paper. The proposed algorithm reduces power consumption of sensor node data communication. It has not researched in LEACH(Low-Energy Adaptive Clustering Hierarchy) routing protocol. As controlling the active/sleep mode based on the measured data by sensor node, the energy consumption is able to be managed. In the event, the data is transferred to the local cluster head already set. The other side, this algorithm send the data as dependent on the information such as initial and present energy, and the number of rounds that are transformed into cluster header and then transferred. In this situation, the assignment of each node to cluster head evenly is very important. We selected cluster head efficiently and uniformly distributed the energy to each cluster node through the proposed algorithm. Consequently, this caused the extension of the WSN life time.

Anti-carcinogenetic and Anti-metastatic Effects of Extract from Maekmoondong-tang in HepG2 Cells (간암 세포주 HepG2에 대한 맥문동탕(麥門冬湯) 추출물의 항암 및 항전이 효능)

  • Cheon, Myeong-Sook;Chun, Jin-Mi;Yoon, Tae-Sook;Lee, A-Yeong;Moon, Byeong-Cheol;Choo, Byung-Kil;Kim, Seong-Hwan;Kim, Ho-Kyoung
    • The Korea Journal of Herbology
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    • v.24 no.3
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    • pp.161-167
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    • 2009
  • Objectives : Maekmoondong-tang (MMDT), a Korean herbal medicine, has been used to treat severe dry cough in patients with bronchitis and pharyngitis. MMDT has been reported to have anti-inflammatory, anti-allergic, immunomodulatory, secretory-modulating, and metabolic regulatory actions. However, there are no evidence in regard to the effects of MMDT on carcinogenesis and metastasis. Here, we investigated the effects of 70% ethanol extract of MMDT on cell viability, apoptosis, and motility in human hepatocarcinoma HepG2 cells. Methods : Cell viability was measured using the CCK-8 assay, and the apoptosis induction was evaluated by caspase-3 activity. To detect apoptotic features, the cells treated with MMDT were stained with 4'-6-diamidino-2-phenylindole (DAPI). Cell motility was examined by Boyden chamber assay and Real-time Cell Index of Migration assay. Gelatin zymography also performed to measure matrix metalloproteinase (MMP)-2/9 activity. Results : We found that MMDT significantly inhibited cell proliferation and increased caspase-3 activity in a dose-dependent manner in HepG2 cells. Apoptotic features such as chromatin condensation and apoptotic bodies were observed in MMDT-treated cells by DAPI staining. MMDT also suppressed PMA-induced cell motility and activities of MMP-2/9. Conclusions : Our results exhibited that MMDT possess the anti-carcinogenetic and anti-metastatic activities via caspase-3 activation and down-regulation of cell motility and invasion in HepG2 cells. Therefore, these findings suggest that MMDT could be potentially applied to the prevention and treatment of cancer.

N6-Methyladenosine modification (m6A) of circRNA-ZNF638 contributes to the induced activation of SHF stem cells through miR-361-5p/Wnt5a axis in cashmere goats

  • Ronghuan Yin;Ronglan Yin;Man Bai;Yixing Fan;Zeying Wang;Yubo Zhu;Qi Zhang;Taiyu Hui;Jincheng Shen;Siyu Feng;Wenlin Bai
    • Animal Bioscience
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    • v.36 no.4
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    • pp.555-569
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    • 2023
  • Objective: The objective of this study was to investigate the effects of N6-Methyladenosine modification-circRNA-zinc finger protein 638 (m6A-circRNA-ZNF638) on the induced activation of secondary hair follicle (SHF) stem cells with its potential mechanisms in cashmere goats. Methods: The m6A modification of ZNF638 was analyzed using methylation immunoprecipitation with real-time quantitative polymerase chain reaction technique in SHF stem cells. The effects of circRNA-ZNF638 on the induced activation of SHF stem cells in m6A dependence were evaluated through the overexpression of circRNA-ZNF638/its m6A-deficient mutants in circRNA-ZNF638 knockdown SHF stem cells. The competitive binding of miR-361-5p to circRNA-ZNF638/Wnt5a 3'- untranslated region was analyzed through Dual-luciferase reporter assay. Results: The m6A-circRNA-ZNF638 had significantly higher transcription at anagen SHF bulge of cashmere goats compared with that at telogen, as well as it positively regulated the induced activation of SHF-stem cells in cashmere goats. Mechanismly, m6A-circRNA-ZNF638 sponged miR-361-5p to heighten the transcriptional expression of Wnt5a gene in SHF-stem cells. We further demonstrated that the internal m6A modification within circRNA-ZNF638 is required for mediating the miR-361-5p/Wnt5a pathway to regulate the induced activation of SHF stem cells through an introducing of m6A-deficient mutant of circRNA-ZNF638. Conclusion: The circRNA-ZNF638 contributes the proper induced activation of SHF-stem cells in cashmere goats in m6A-dependent manner through miR-361-5p/Wnt5a axis.