• Title/Summary/Keyword: reference value

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A Comparison of Pixel- and Segment-based Classification for Tree Species Classification using QuickBird Imagery (QuickBird 위성영상을 이용한 수종분류에서 픽셀과 분할기반 분류방법의 정확도 비교)

  • Chung, Sang Young;Yim, Jong Su;Shin, Man Yong
    • Journal of Korean Society of Forest Science
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    • v.100 no.4
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    • pp.540-547
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    • 2011
  • This study was conducted to compare classification accuracy by tree species using QuickBird imagery for pixel- and segment-based classifications that have been mostly applied to classify land covers. A total of 398 points was used as training and reference data. Based on this points, the points were classified into fourteen land cover classes: four coniferous and seven deciduous tree species in forest classes, and three non-forested classes. In pixel-based classification, three images obtained by using raw spectral values, three tasseled indices, and three components from principal component analysis were produced. For the both classification processes, the maximum likelihood method was applied. In the pixel-based classification, it was resulted that the classification accuracy with raw spectral values was better than those by the other band combinations. As resulted that, the segment-based classification with a scale factor of 50% provided the most accurate classification (overall accuracy:76% and ${\hat{k}}$ value:0.74) compared to the other scale factors and pixel-based classification.

Improvement of Acid Digestion Method by Microwave for Hazardous Heavy Metal Analysis of Solid Refuse Fuel (고형연료제품의 유해중금속 분석을 위한 마이크로파 산 분해법의 개선)

  • Yang, Won-Seok;Park, Ho-Yeun;Kang, Jun-Gu;Lee, Young-Jin;Lee, Young-Kee;Yoon, Young-Wook;Jeon, Tae-Wan
    • Journal of Korea Society of Waste Management
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    • v.35 no.7
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    • pp.616-626
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    • 2018
  • The quality standards of solid refuse fuel (SRF) define the values for 12 physico-chemical properties, including moisture, lower heating value, and metal compounds, according to Article 20 of the Enforcement Rules of the Act on Resource Saving and Recycling Promotion. These parameters are evaluated via various SRF Quality Test Methods, but problems related to the heavy metal content have been observed in the microwave acid digestion method. Therefore, these methods and their applicability need improvement. In this study, the appropriate testing conditions were derived by varying the parameters of microwave acid digestion, such as microwave power and pre-treatment time. The pre-treatment of SRF as a function of the microwave power revealed an incomplete decomposition of the sample at 600 W, and the heavy metal content analysis was difficult to perform under 9 mL of nitric acid and 3 mL of hydrochloric acid. The experiments with the reference materials under nitric acid at 600 W lasted 30 minutes, and 1,000 W for 20 or 30 minutes were considered optimal conditions. The results confirmed that a mixture of SRF and an acid would take about 20 minutes to reach $180^{\circ}C$, requiring at least 30 minutes of pre-treatment. The accuracy was within 30% of the standard deviation, with a precision of 70 ~ 130% of the heavy metal recovery rate. By applying these conditions to SRF, the results for each condition were not significantly different and the heavy metal standards for As, Pb, Cd, and Cr were satisfied.

Standardization and HPTLC Fingerprinting of a Polyherbal Unani Formulation

  • Beg, Mirza Belal;Viquar, Uzma;Naikodi, Mohammad Abdul Rasheed;Suhail, Habiba;Kazmi, Munawwar Husain
    • CELLMED
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    • v.11 no.1
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    • pp.4.1-4.8
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    • 2021
  • Background: The Unani system of medicine has been practised since centuries for the treatment of a range of diseases. In spite of their efficacy they have been widely criticised due to the lack of standardization and poor quality control. Standardization of Unani medicine is a valuable issue at the present because they are very prone to contamination, deterioration, adulteration and variation in composition due to biodiversity as well as careless collection. Objective: To Standardize and Development of HPTLC Fingerprinting of a polyherbal Unani formulation Qurs-e-Safa. Materials and methods: The conventional and modern analytical techniques were used to standardise Qurs-e-Safa. The study was carried into three different batches of Qurs-e-Safa prepared with its ingredients. The parameters studied are organoleptic, microscopic, physicochemical parameters, phytochemical screening, TLC, HPTLC profile, aflatoxin, microbial load and heavy metal analysis. Results and conclusion: Qurṣ-e-Sa'fa is dark yellow in colour and aromatic smell. Uniformity of diameter and weight variation were found to be 13 ± 0, and 524.7 ± 1.72 mg. friability, hardness and disintegration time of all 3 batches were found to be (0.0615 ± 0.004, 0.0885 ± 0.0047 and 0.0725 ± 0.0058), (3.5 ± 0.2886, 3.67 ± 0.1674 and 3.67 ± 0.1674) and (16 to 17 minutes). Extractive value were found to be maximum in distilled water (38.488 ± 0.20, 37.3824 ± 0.38 and 39.8177 ± 0.13) followed by alcohol (27.5406 ± 0.54, 27.5656 ± 0.32 and 26.9229 ± 0.25). Loss of weight on drying, pH, total ash, acid insoluble ash, qualitative test was set in. Phytochemical screening revealed the presence of Carbohydrates, Phenols, Resins, Proteins, Steroids, fixed oil and Flavonoids. The microbial load was found absent and heavy metals were within permissible limits. The data evolved from the study may serve as a reference to validate and also help in the quality control of other finished products in future research.

Estimation of Dietary Iodine Intake of Koreans through a Total Diet Study (TDS) (한국형 총식이조사에 근거한 우리 국민의 식품 기인 요오드 섭취량 추정)

  • Lee, Jeeyeon;Yeoh, Yoonjae;Seo, Min Jeong;Lee, Gae Ho;Kim, Cho-il
    • Korean Journal of Community Nutrition
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    • v.26 no.1
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    • pp.48-55
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    • 2021
  • Objectives: This study was conducted to estimate the dietary iodine intake of Koreans by a Total Diet Study (TDS) which provides 'closer-to-real' estimates of exposure to hazardous materials and nutrients through an analysis of table-ready (cooked) samples of foods. Methods: Dietary intake data from 2013-2017 Korea National Health and Nutrition Examination Survey (KNHANES) was used to select representative foods (RFs) for iodine analysis. A total of 115 RFs were selected and 158 'RF × cooking method-combination' pairs were derived by pairing each RF to corresponding cooking method(s) used more frequently. RFs were collected from 9 mega-markets in 9 metropolitan cities nationwide and mixed into composites prior to cooking preparation to a 'table ready' state for iodine analysis by inductively coupled plasma mass spectrometry. Iodine intake of Koreans was estimated based on the food intake data of the 2016-2018 KNHANES. Results: High iodine content was detected in seaweeds such as sea mustard and kelp. The mean iodine intake/capita/day was 418.4 ㎍ and the median value was 129.0 ㎍. Seaweeds contributed to 77.4% of the total iodine intake and the contribution by food item was as follows: sea mustard (44.0%), kelp (20.4%), laver (13.1%), milk (3.9%), egg (3.5%). Compared to the Dietary Reference Intakes for Koreans 2020, the proportion of people with iodine intake exceeding the tolerable upper intake level or below the estimated average requirement was high in the physiologically vulnerable groups (infants, children, pregnant women, and lactating women). Conclusions: The results, drawn from a TDS, are regarded closer to real estimates for iodine intake of Koreans compared with values in existing literature, which were based on a very limited variety of foods. On the other hand, it seems necessary to seek out solutions for the problematic iodine intake among physiologically vulnerable groups through in-depth analyses on food intake data collected with significant scale & quality.

A Study on the Creation Process of Dance based on the Concept of Murray Schafer's Soundscape (Murray Schafer의 사운드스케이프 개념을 바탕으로 한 무용작품 의 창작과정 연구)

  • Ra, Se-Young;Choe, Sang-Cheul
    • The Journal of the Korea Contents Association
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    • v.21 no.6
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    • pp.425-434
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    • 2021
  • This study is subjected to two linked research. First is the creation process of dance work applying noise and non-musical sounds in our daily life based on understanding the classification, perception, and factor of the sound, through Murray Schafer's concept of 'soundscape'. Second is to find the value of new type of choreography and musical effect of creation process of the dance work . According to methodological research of practice-based research, three stages which is practice, theory and evaluation were accumulated as somatic data, And the analysis was provided a basis by presenting in a figuration, form of the movement and method of specialization with reference to the paper 『space design and forming practice』(2003). As a result, the creation process was able to discover the musical effect of the sound in daily life and new method of choreography, and also find the possibilities that sound could convey the theme of the dance work, the meaning of the movement and the overall atmosphere of the work to audience. In addition, It is expected that will have been made another new creation environment by potential that music has based on concept 'soundscape'.

A study on the risk assessment system for the harmful marine species: the legal problems and solutions (유해해양생물 위해성평가 제도의 문제점 및 개선방안 연구)

  • Lee, Chang Su;Moh, Youngdawng
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.691-704
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    • 2020
  • The Ministry of Oceans and Fisheries has designated 17 species as harmful marine organisms with the purpose of managing harmful marine species that threaten health and property. In designating and managing harmful marine species, detailed and effective regulations were originally established in November 2015, and a minor amendment of the directive was published in 2019 - Directive on Designating and Managing Marine Ecosystem Invasive Species and Harmful Marine Species (hereinafter, the Directive). Thus, this study had two aims: Firstly, to increase public awareness of the harmful marine species management system run by the Ministry of Oceans and Fisheries via description of the present harmful marine species risk assessment system. Secondly, to improve the current risk assessment system by providing policy suggestions developed through review of the present harmful marine species designation and management system. In so doing, this study reviewed the 'harmful marine species - harmfulness risk assessment system' in both the definitions of "risk" and "assessment". As a result, the present definition of 'risk' adequately fulfills the policy aims on the Regulation of Marine Ecosystem, which includes an economic value. However, it seems that there is a loophole in the rules of risk assessment, lacking terms of reference in the definition of "risk". Moreover, with regards to risk assessment, a quantitative risk assessment system was sufficient but lacked elements of qualitative risk, suggesting future research in this area may prove useful in the management of harmful marine species.

Application of Integrated Modelling Framework Consisted of Delft3D and HABITAT for Habitat Suitability Assessment (생물서식지 적합성 평가를 위한 Delft3D와 HABITAT 모델의 연계 적용)

  • Lim, Hyejung;Na, Eun Hye;Jeon, Hyeong Cheol;Song, Hojin;Yoo, Hojun;Hwang, Soon Hong;Ryu, Hui-Seong
    • Journal of Korean Society on Water Environment
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    • v.37 no.3
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    • pp.217-228
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    • 2021
  • This paper discusses a methodology where an integrated modelling framework is used to quantify the risk derived from anthropic activities on habitats and species. To achieve this purpose, a tool comprising the Delft3D and HABITAT model, was applied in the Yeongsan river. Delft3D effectively simulated the operational condition and flow of weirs in river. In accuracy evaluation of the Delft3D-FLOW, the Bias, Pbias, Mean Absolute Error (MAE), Nash-Sutcliffe Efficiency (NSE), and Index of Agreement (IOA) were used, and the result was evaluated as grade above 'Satisfactory'. The HABITAT calculated Habitat Suitability Value (HSV) for the following eight species: mammal, fish, aquatic plant, and benthic macroinvertebrate. An Area was defined as a suitable habitat if the HSV was larger than 0.5. HABITAT was judged accurately by measuring the Correct Classification rate (CCR) and the area under the ROC curve (AUC). For benthic macroinvertebrate, the CCR and AUC were 77% and 0.834, respectively, at thresholds of 0.017 and 4 inds/m2 for HSV and individuals per unit area. This meant that the HABITAT model accurately predicted the appearance of the benthic macroinvertebrates by approximately 77% and that the probability of false alarms was also very low. As a result of evaluating the suitability of habitats, in the Yeongsan river, if the annual "lowest level" (Seungchon weir: 2.5 EL.m/ Juksan weir: -1.35 EL.m) was maintained, the average habitat improvement effect of 6.5%P compared to the 'reference' scenario was predicted. Consequently, it was demonstrated that the integrated modelling framework for habitat suitability assessment is able to support the remedy aquatic ecological management.

Analysis of the crack propagation rules and regional damage characteristics of rock specimens

  • Li, Yangyang;Xu, Yadong;Zhang, Shichuan;Fan, Jing;Du, Guobin;Su, Lu;Fu, Guangsheng
    • Geomechanics and Engineering
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    • v.24 no.3
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    • pp.215-226
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    • 2021
  • To study the evolution mechanism of cracks in rocks with multiple defects, rock-like samples with multiple defects, such as strip-shaped through-going cracks and cavity groups, are used, and the crack propagation law and changes in AE (acoustic emission) and strain of cavity groups under different inclination angles are studied. According to the test results, an increase in the cavity group inclination angle can facilitate the initial damage degree of the rock and weaken the crack initiation stress; the initial crack initiation direction is approximately 90°, and the extension angle is approximately 75~90° from the strip-shaped through-going cracks; thus, the relationship between crack development and cavity group initiation strengthens. The specific performance is as follows: when the initiation angle is 30°, the cracks between the cavities in the cavity group develop relatively independently along the parallel direction of the external load; when the angle is 75°, the cracks between the cavities in the cavity group can interpenetrate, and slip can occur along the inclination of the cavity group under the action of the shear mechanism rupture. With the increase in the inclination angle of the cavity group, the AE energy fluctuation frequency at the peak stress increases, and the stress drop is obvious. The larger the cavity group inclination angle is, the more obvious the energy accumulation and the more severe the rock damage; when the cavity group angle is 30° or 75°, the peak strain of the local area below the strip-shaped through-going fracture plane is approximately three times that when the cavity group angle is 45° and 60°, indicating that cracks are easily generated in the local area monitored by the strain gauge at this angle, and the further development of the cracks weakens the strength of the rock, thereby increasing the probability of major engineering quality damage. The research results will have important reference value for hazard prevention in underground engineering projects through rock with natural and artificial defects, including tunnels and air-raid shelters.

A Study on the Development of Human Resource Factors in the Service Economy Era (서비스경제시대 인재상요소 개발에 관한 연구)

  • Baek, Kyeonghui;Kim, Hyunsoo
    • The Journal of the Korea Contents Association
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    • v.21 no.2
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    • pp.572-586
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    • 2021
  • With the advent of the 4th Industrial Revolution, the modern economy is transforming into a service-oriented economic society, and there is a growing need for companies to reorganize organizational culture, values, and human resources to suit the changing environment. Especially, even when times change, human capital is the most important factor in maintaining sustainable development and Corporate value, since all work is done by people. Therefore, in this study, in order to recognize the importance of human resources and verify the appropriate human resources for the changing service economy era, we reviewed the literature and that drew the human resources suitable for the recent service economy era Based on this, an empirical study was conducted on whether the suggested human resources factors were useful. To this end, a feasibility analysis, reliability analysis, correlation analysis, confirmatory factor analysis, and reference validity were conducted by dividing into a preliminary survey and a main survey. As a result, it was finally drawn with 30 items, 7 factors. The results of this study are expected to be used as basic data in various fields of research on human resources in the service economy era, and in-depth empirical studies are needed in the future.

Estimation of Multi-Route Exposure and Aggregated Risk Assessment for Cadmium and Lead (카드뮴과 납의 다경로 노출량 추정 및 통합 위해성 평가)

  • Yu, Changwoo;Kwon, Hoonjeong
    • Journal of Food Hygiene and Safety
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    • v.35 no.6
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    • pp.587-601
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    • 2020
  • Exposure to hazardous substances occurs through multiple pathways. Aggregated risk assessment, which includes all potential exposure pathways to a single toxicant, is necessary to prevent exposure to harmful substances. We aimed to estimate cadmium and lead exposure through various media, such as food, water, air, smoking, cosmetics, and female hygiene products. This study covered 10,733 subjects from the Seventh Korea National Health and Nutrition Examination Survey(2016, 2017). Dietary exposure was estimated using 24-hour recall data. For water and inhalational exposure, regional variations were considered. Water was classified as tap, bottled, and public water. Inhalational exposure was estimated using the '2014 Time Use Survey' based on daily lifestyle and social status. The frequency and volume of cosmetic usage were randomly approximated by sex and age. Post-menarcheal and premenopausal women were assumed to use feminine hygiene products. Non-carcinogenic aggregated risks were estimated using the Aggregate Risk Index from EPAs and the Total Exposure Hazard Index from Korean government guidelines. For carcinogenic risk assessment, excessive cancer risk was estimated. Ingestion, especially food, was the major route for both cadmium and lead exposure. Smoking was also associated with high cadmium exposure. Exposure to lead from cosmetics was remarkable but not critical. In aggregate risk assessments, median cadmium and lead exposure did not exceed the reference value. Sex, age, smoking status, and income affected exposure levels, unlike to regional variations.