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Evaluating the contribution of calculation components to the uncertainty of standardized precipitation index using a linear mixed model (선형혼합모형을 활용한 표준강수지수 계산 인자들의 불확실성에 대한 기여도 평가)

  • Shin, Ji Yae;Lee, Baesung;Yoon, Hyeon-Cheol;Kwon, Hyun-Han;Kim, Tae-Woong
    • Journal of Korea Water Resources Association
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    • v.56 no.8
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    • pp.509-520
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    • 2023
  • Various drought indices are widely used for assessing drought conditions which are affected by many factors such as precipitation, soil moisture, and runoff. The values of drought indices varies depending on hydro-meteorological data and calculation formulas, and the judgment of the drought condition may also vary. This study selected four calculation components such as precipitation data length, accumulation period, probability distribution function, and parameter estimation method as the sources of uncertainty in the calculation of standardized precipitation index (SPI), and evaluated their contributions to the uncertainty using root mean square error (RMSE) and linear mixed model (LMM). The RMSE estimated the overall errors in the SPI calculation, and the LMM was used to quantify the uncertainty contribution of each factor. The results showed that as the accumulation period increased and the data period extended, the RMSEs decreased. The comparison of relative uncertainty using LMM indicated that the sample size had the greatest impact on the SPI calculation. In addition, as sample size increased, the relative uncertainty related to the sample size used for SPI calculation decreased and the relative uncertainty associated with accumulation period and parameter estimation increased. In conclusion, to reduce the uncertainty in the SPI calculation, it is essential to collect long-term data first, followed by the appropriate selection of probability distribution models and parameter estimation methods that represent well the data characteristics.

An Analysis of the Rice Situation in Nicaragua for Improving National Production.

  • Chang-Min Lee;Oporta Juan;Ho-Ki Park;Hyun-Su Park;Jeonghwan Seo;Man-Kee Baek;Jae-Ryoung Park;O-Young Jeong
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.90-90
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    • 2022
  • Nicaragua is located in Central America, climatic conditions are considered tropical dry forest. Statistics reflex that in Nicaragua exits 24,000 rice farmers. National rice production only covers 73% of the national consumption. It exists two sowing system: irrigation and rainfed. Varieties used in both systems are mid-late maturity (120-135 days), there are 14 released varieties for irrigation, eight for rainfed, and eight landraces used in rainfed. The current breeding system (introduction of lines from Colombia) has increased the national production, however, has some limitation due to the lack of enough variability, reducing the proability of finding good genotypes and therefore the possibility of satisfying 100% of the demand. The purpose of this study was to analyze the problems that must be resolved in the short and long term to improve rice productivity in Nicaragua. In this paper we explain some proposal for an improvement plan. The selection of varieties with high adaptability to various cultivation environmental conditions it is necessary, also to thoroughly manage seed purity to supply certified seeds. In rice cultivation technology, it needs to improve seedling standing and weeding effect by improving soil leveling and water-saving cultivation technology. Also, proper fertilization and planting density must be established in irrigated and rain-fed areas. Furthermore, capacity must be strengthened by collecting and training with the most recent agricultural technology information, as well as by revitalizing the union rather than the individual farmer. It is necessary to develop varieties highly adaptable to the Nicaraguan cultivation environment, as well as to expand irrigation facilities and cultivation technology suitable for weather conditions in rain-fed areas. Last, it is necessary to maintain the consistency of agricultural policy for continuous and stable rice production in response to climate change events such as drought or intermittent heavy rain.

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Comparison Analysis on Characteristics and Components of Various Waste Plastic Pyrolysis Oils by Vacuum Distillation Method (감압증류를 통해 분획된 폐플라스틱 열분해유의 특성평가와 구성성분 비교분석 연구)

  • Hwayeon Jeon;Cheol Hwan Jeon;Sung Joon Park;Jae Woo Lee;Jae-kon Kim
    • Clean Technology
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    • v.29 no.4
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    • pp.262-271
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    • 2023
  • Globally, the amount of waste plastics has been occurring to environmental problems. As a result, it is necessary to research methods that utilize waste plastic pyrolysis oil (WPPO) produced by pyrolysis. One such method being studied is utilizing WPPO as a naphtha feedstock. In this study, five types of WPPO were analyzed to determine whether they can be used as raw materials for naphtha. Because of their wide boiling point range, the WPPOs were fractionated into light and heavy fractions through vacuum distillation, and the separation and purification techniques were analyzed using GC-VUV to determine the content of paraffin, olefin, and other compounds. All WPPOs showed high olefin content regardless of the source and fraction. Aromatic and paraffin content varied depending on the source, and oxygen and other compounds also varied significantly by source and fraction. In addition, the light fraction showed a carbon distribution similar to that of naphtha, whereas the heavy fraction showed a carbon distribution of C11 ~ C14. In conclusion, additional processes and raw material selection are required to utilize waste plastic pyrolysis oil as a raw material for naphtha.

A study on TOC monitoring and spatial distribution analysis using a spectrometer in rivers (하천에서의 분광측정기를 이용한 TOC 모니터링 및 공간분포 분석 연구)

  • Yoon, Soo Bin;Lee, Chang Hyun;Kim, Young Do
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.815-822
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    • 2023
  • Organic pollution is one of the most common forms of water contamination. Under the Water Quality Conservation Act, indicators for measuring organic substances include BOD, COD, and TOC. Analysis of BOD and COD is labor-intensive, and in the case of organic substances where biological decomposition is not feasible or toxic substances are present, the accuracy is often low. Therefore, the Ministry of Environment is shifting towards TOC-centric management. With advancements in sensor technology today, various parameters can be monitored using sensors. In this study, digital monitoring of river TOC using a spectrophotometer called Spectro::lyser V3 was conducted. Initially, experiments were carried out at the Andong River Experiment Center to assess the applicability of the measurement equipment. Subsequently, data collected at the confluence of the Nakdong River was analyzed for the spatial distribution of TOC using the Kriging technique. This research proposes the utilization of sensors for river TOC monitoring and spatial distribution analysis. Real-time monitoring of changes in river TOC concentration can serve as fundamental data for pollution monitoring and response. Sensor-based river monitoring offers advantages in terms of temporal resolution and real-time data acquisition. When various spatial information interpretation methods are applied, it is expected to contribute to diverse studies such as aquatic ecological health, river water source selection, and stratification analysis in the future.

An Analysis of the Rationale and Format of Music Intervention Studies With Patients Receiving Hospice or Palliative Care in Korea (국내 호스피스·완화의료 환자 대상 음악중재연구 내 중재 제시 방법 및 논거 분석)

  • Oh, Joo Eun
    • Journal of Music and Human Behavior
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    • v.20 no.2
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    • pp.1-32
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    • 2023
  • The purpose of this study was to analyze the rationale and format of music therapy interventions with patients receiving hospice or palliative care in Korea. Through this analysis, I examined whether the music intervention used was based on a valid rationale and represented the professionalism expected of today's music therapy interventions. A total of 12 studies that met the selection criteria were identified, and the overall characteristics of each study and its format were analyzed. As a result of the analysis, it was confirmed that the rationale for each study and its format were influenced by the author's research field. The analysis also showed that the research on music-based interventions in hospice or palliative care settings was insufficient and involved a mix of professional and nonprofessional interventions. The results of this study suggest that importance of researchers possessing professional competence which requires offering a clear justification for their choice of interventions, music, and instruments. Additionally, these results emphasize the need for further development of evidence-based music therapy approaches in hospice and palliative care settings as the role of music in supporting patients in these environments has gained increasing recognition and validation.

A Qualitative Research on the Evaluation of Healthcare and Welfare Network for Vulnerable Populations : Focusing on the Dalgubeol Health Doctor Services (취약계층 대상 보건의료·복지 네트워크 사업 성과에 대한 질적연구 : 달구벌건강주치의사업을 중심으로)

  • Su-Jin Lee;Jong-Yeon Kim;Jae-Wook Kang;Hye-Jin Lee
    • Journal of agricultural medicine and community health
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    • v.48 no.4
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    • pp.262-274
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    • 2023
  • Objectives: This study examined the evaluation and potential improvements of 'Integrated Healthcare and Social Welfare service model' based on the experiences of practitioners from institutions participating in the 'Dalgubeol Health Doctor Services' and the service recipients. Methods: Qualitative research was conducted from September to November 2022 in this study, focusing on 4 providers from the dedicated Dalgubeol Health Doctor Services Team, 5 contact partners from affiliated organizations, and 6 service beneficiaries. The data gathered underwent thematic analysis. Results: The evaluation indicated that Dalgubeol Health Doctor Services has proven to be effective in addressing the complex needs of vulnerable populations. By providing integrated services through quick and simple beneficiary selection and resource linkage, it has contributed to the resolution of complex demands, recovery of positive attitudes towards life, and improvement in quality of life for users who have fear the use of medical and welfare services. Dalgubeol Health Doctor Services has established an integrated health care system involving not only public but also private organizations, from the referral agency to the service provider. Centered around Daegu Medical Center and involving five tertiary hospitals, it has established a model that supports treatment appropriate to the severity of the patient, from mild to severe. Conclusions: These findings indicate an enhancement in health equity, achieved through the active identification and subsequent health and welfare issue resolution of individuals marginalized from medical benefits.

Analysis-based Pedestrian Traffic Incident Analysis Based on Logistic Regression (로지스틱 회귀분석 기반 노인 보행자 교통사고 요인 분석)

  • Siwon Kim;Jeongwon Gil;Jaekyung Kwon;Jae seong Hwang;Choul ki Lee
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.2
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    • pp.15-31
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    • 2024
  • The characteristics of elderly traffic accidents were identified by reflecting the situation of the elderly population in Korea, which is entering an ultra-aging society, and the relationship between independent and dependent variables was analyzed by classifying traffic accidents of serious or higher and traffic accidents of minor or lower in elderly pedestrian traffic accidents using binomial variables. Data collection, processing, and variable selection were performed by acquiring data from the elderly pedestrian traffic accident analysis system (TAAS) for the past 10 years (from 13 to 22 years), and basic statistics and analysis by accident factors were performed. A total of 15 influencing variables were derived by applying the logistic regression model, and the influencing variables that have the greatest influence on the probability of a traffic accident involving severe or higher elderly pedestrians were derived. After that, statistical tests were performed to analyze the suitability of the logistic model, and a method for predicting the probability of a traffic accident according to the construction of a prediction model was presented.

Development of a Real-time Action Recognition-Based Child Behavior Analysis Service System (실시간 행동인식 기반 아동 행동분석 서비스 시스템 개발)

  • Chimin Oh;Seonwoo Kim;Jeongmin Park;Injang Jo;Jaein Kim;Chilwoo Lee
    • Smart Media Journal
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    • v.13 no.2
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    • pp.68-84
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    • 2024
  • This paper describes the development of a system and algorithms for high-quality welfare services by recognizing behavior development indicators (activity, sociability, danger) in children aged 0 to 2 years old using action recognition technology. Action recognition targeted 11 behaviors from lying down in 0-year-olds to jumping in 2-year-olds, using data directly obtained from actual videos provided for research purposes by three nurseries in the Gwangju and Jeonnam regions. A dataset of 1,867 actions from 425 clip videos was built for these 11 behaviors, achieving an average recognition accuracy of 97.4%. Additionally, for real-world application, the Edge Video Analyzer (EVA), a behavior analysis device, was developed and implemented with a region-specific random frame selection-based PoseC3D algorithm, capable of recognizing actions in real-time for up to 30 people in four-channel videos. The developed system was installed in three nurseries, tested by ten childcare teachers over a month, and evaluated through surveys, resulting in a perceived accuracy of 91 points and a service satisfaction score of 94 points.

Comparison of the effects of two different styles of orally prescribing prednisolone on postoperative sequelae of surgical extraction of an impacted mandibular third molar: a single-blind randomized study

  • Mohammed Mousa H. Bakri;Faisal Hussain Alabdali;Rashed Hussain Mahzari;Thamer Jabril Rajhi;Norah Mohammed Gohal;Rehab Abdu Sufyani;Asma Ali Hezam;Ahtesham Ahmed Qurishi;Hamed Mousa Bakri;Fareedi Mukram Ali
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.1
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    • pp.27-34
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    • 2024
  • Objectives: Surgical intervention for removal of an impacted third molar can lead to significant pain and swelling. Corticosteroids show promise for mitigating postoperative sequelae across various surgical contexts. The use of corticosteroids following minor oral surgery, though controversial, has already been proven effective. However, little research has explored peroral prescription of corticosteroids despite its convenience for outpatients and for non-surgeons like implantologists and periodontists and others who don't have access to needle injections. The aim of this study was to address a void in the literature by comparing the effects of two styles of preoral administration of prednisolone after surgical removal of the mandibular third molar and to determine which style minimizes postoperative sequelae. Materials and Methods: A randomized, split-mouth clinical study was conducted to investigate the efficacy of two different styles of preoral prednisolone in mitigating postoperative sequelae following surgical extraction of impacted mandibular third molars. Fifteen participants were enrolled in the study. Random selection was used to determine the prescription style for the right and left mandibular arch. Group A included those who received a single dose of prednisolone 25 mg, while group B received prednisolone 5 mg postoperatively for a period of three days (5 mg three times/day on the first postoperative day, 5 mg twice/day on the second postoperative day; 5 mg once/day on the third postoperative day). Results: There was a significant difference in the distance between the corner of the mouth and tragus, which decreased with the time interval with respect to group B when compared to group A. Conclusion: The present study showed that a three-day tapered dose of prednisolone postoperatively was more effective in reducing post-extraction sequelae than a single-dose regimen.

Optimization of MRI Protocol for the Musculoskeletal System (근골격계 자기공명영상 프로토콜의 최적화)

  • Hong Seon Lee;Young Han Lee;Inha Jung;Ok Kyu Song;Sungjun Kim;Ho-Taek Song;Jin-Suck Suh
    • Journal of the Korean Society of Radiology
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    • v.81 no.1
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    • pp.21-40
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    • 2020
  • Magnetic resonance imaging (MRI) is an essential modality for the diagnosis of musculoskeletal system defects because of its higher soft-tissue contrast and spatial resolution. With the recent development of MRI-related technology, faster imaging and various image plane reconstructions are possible, enabling better assessment of three-dimensional musculoskeletal anatomy and lesions. Furthermore, the image quality, diagnostic accuracy, and acquisition time depend on the MRI protocol used. Moreover, the protocol affects the efficiency of the MRI scanner. Therefore, it is important for a radiologist to optimize the MRI protocol. In this review, we will provide guidance on patient positioning; selection of the radiofrequency coil, pulse sequences, and imaging planes; and control of MRI parameters to help optimize the MRI protocol for the six major joints of the musculoskeletal system.