• Title/Summary/Keyword: Sampling techniques

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Effect of Soil Micro-environments on the Remediation Efficiency of Contaminated Soil and Groundwater: Review and Case Study (토양지하수 미세환경과 오염정화효율과의 상관성 고찰)

  • Shim, Moo Joon;Yang, Jung-Seok;Lee, Mi Jung;Lee, Giehyeon;Park, Jae Seon;Kim, Guk Jin;Min, Sang Yoon;Kim, Joo Young;Choi, Min Joo;Kim, Min Chan;Lim, Jong Hwan;Kwon, Man Jae
    • Journal of Soil and Groundwater Environment
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    • v.19 no.1
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    • pp.34-45
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    • 2014
  • A variety of physical, chemical, and microbiological techniques have been developed to deal with soil and groundwater contamination. However, in the presence of the large portion of soil micro-environments, contaminant rebound and/or tailing have been frequently reported. Case study of total petroleum hydrocarbons (TPH) removal by full-scale land farming showed that contaminant rebound and/or tailing occurred in 9 out of total 21 cases and subsequently resulted in problems of a long term operation to satisfy TPH guidelines of contaminated soil and groundwater. The main cause of contaminant rebound and tailing is considered to be the strong interactions between contaminants and micro-environments including micro-particles, micro-pores, and organic matter. Thus, this study reviewed the effects of soil micro-environments of soil and groundwater on the removal efficiency for both heavy metals and petroleum contaminants. In addition, the various methods of sampling, analysis, and assessment of soil micro-environments were evaluated. Thorough understanding of the effects of soil micro-environments on contaminant removal will be essential to achieve a cost-effective and efficient solution to contaminated sites.

Discontinuity Analysis Method using Reverse Engineering (역분석공학기법을 이용한 불연속면 분석 프로그램 개발)

  • Park, Eui-Seob;Jung, Yong-Bok;Ryu, Chang-Ha;SunWoo, Choon;Choi, Yong-Kun;Heo, Sung;Cheon, Dae-Sung
    • Tunnel and Underground Space
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    • v.17 no.3 s.68
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    • pp.165-174
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    • 2007
  • The technique, which reproduces the figures of objects from measured data of the objects using 3-D laser scanner, is called reverse engineering. Recently, research studies into applications of reverse engineering to rock engineering are increasing in number, in the discontinuity surveys for rock slopes out of man's reach, or rapid discontinuity surveys for wide range areas. For analysis of discontinuity using reverse engineering, a program for processing point clouds data from the 3-D laser scanner, for sampling from these point clouds data, and finally analyzing the discontinuity is needed. However, existing programs rarely have sufficient functions to properly analyze the discontinuities. In this study, a program was developed, which can automatically sample discontinuities from the point clouds data which measured in a rock slope using a 3-D laser scanner, and which can also undertake statistical analysis of the discontinuities. This developed program was verified by the application of discontinuity surveys in a rock slope and a tunnel. By undertaking the discontinuity survey using a 3-D laser scanner and the developed program, the feasibility and rapidity of such surveys is expected to improve in areas out of man's reach in geotechnical surveys. Taking into consideration the fact that the international level of related techniques is at a rudimentary stage, the possibility of prior occupation of a broad market is also expected.

Effects of Scalp Myofascial Technique and Manual Therapy on Pain and Quality of Life in Tension Type Headache Patients : Six Month Follow-up Results (두피근막이완기법과 도수치료가 긴장성두통 환자의 통증과 삶의 질에 미치는 영향 : 6개월 추적연구)

  • Lee, Hwa-Gyeong;Kim, Seong-Yeol
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.2
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    • pp.119-130
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    • 2021
  • Purpose : We aimed to validate a new manual therapy to treat tension type headache(TTH) by applying myofascial release techniques to the scalp and to examine the changes in the quality of life and the headache characteristics after treatment and at the 6-month follow-up. Methods : Thirty patients were recruited in this study and were assigned to two groups through simple random sampling. Fifteen patients were assigned to the manual therapy group (MT) and 15 patients to the scalp myofascial release technique (SMT) group. However, five patients from the MT group and one from the SMT group were excluded. Therefore, 24 patients with TTH (10 males, 14 females) participated in the study. Patients underwent either MT or SMT. The procedures were performed by a physical therapist twice per week for 4 weeks. The quality of life [using the brief pain inventory (BPI) and the headache impact test (HIT)], and the frequency, duration, and intensity of the headache [on a visual analog scale (VAS)] were assessed before and after the treatment, and at the follow-up. Results : After 4 weeks of SMT, the frequency (p<.001), duration (p<.05), and intensity (p<.001) of the headache and the quality of life (HIT; p <.001, BPI; p<.001) significantly improved in the patients with TTH. The improvement in these parameters remained significant even after 6 months of follow-up. Similarly, After 4 weeks of MT, the frequency (p<.05), duration (p<.05), and intensity (p<.01) of the headache, and the quality of life (HIT; p<.05, BPI; p<.001) significantly improved in the patients with TTH. The improvement in these parameters remained significant even after 6 months of follow-up. There was no significant difference in these parameters between the two groups. Conclusion : It has been suggested that MT using the SMT can be used as a non-invasive treatment to treat the frequency, duration, and intensity of the TTH, and to improve the quality of life.

Principles of Archaeogenetics and the Current Trends of Ancient Genome Studies (고고유전학의 분석 원리와 최근 고유전체 연구 동향)

  • Kim, Taeho;Woo, Eun Jin;Pak, Sunyoung
    • Anatomy & Biological Anthropology
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    • v.31 no.4
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    • pp.105-119
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    • 2018
  • Archaeogenetics is an academic discipline that aims to establish scientific facts of human history by integrating ancient DNA analyses with archaeological and anthropological evidence. After ancient DNA research was initiated about 30 years ago, it has been innovated so rapidly that the range of analysis has been extended toward the whole genome sequence of ancient genomes in recent 10 years. By this development, researchers have been able to study in detail the origins and migration patterns of hominin species and ancient human populations by approaches of evolutionary genetics. This study has reviewed main principles of the archaeogenetic analysis and the current trends of ancient genome studies with recent achievements. While sampling techniques and statistical analyses have been improved, typical research methods have been established by the findings on hominins and ancient western Eurasia populations. Recently, archaeogenecists have been applying the methods to studying those in other geographical areas. Nonetheless, there is still the lack of ancient genome research about populations in Eastern Asia including the Korean peninsula. This review ultimately aims to predict possibilities and promise of future ancient genome studies of ancient Korean populations.

Prediction of Ship Roll Motion using Machine Learning-based Surrogate Model (기계학습기반의 근사모델을 이용한 선박 횡동요 운동 예측)

  • Kim, Young-Rong;Park, Jun-Bum;Moon, Serng-Bae
    • Journal of Navigation and Port Research
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    • v.42 no.6
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    • pp.395-405
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    • 2018
  • Seakeeping safety module in Korean e-Navigation system is one of the ship remote monitoring services that is employed to ensure the safety of ships by monitoring the ship's real time performance and providing a warning in advance when the abnormal conditions are encountered in seakeeping performance. In general, seakeeping performance has been evaluated by simulating ship motion analysis under specific conditions for its design. However, due to restriction of computation time, it is not realistic to perform simulations to evaluate seakeeping performance under real-time operation conditions. This study aims to introduce a reasonable and faster method to predict a ship's roll motion which is one of the factors used to evaluate a ship's seakeeping performance by using a machine learning-based surrogate model. Through the application of various learning techniques and sampling conditions on training data, it was observed that the difference of roll motion between a given surrogate model and motion analysis was within 1%. Therefore, it can be concluded that this method can be useful to evaluate the seakeeping performance of a ship in real-time operation.

Insights Into Emissions and Exposures From Use of Industrial-Scale Additive Manufacturing Machines

  • Stefaniak, A.B.;Johnson, A.R.;du Preez, S.;Hammond, D.R.;Wells, J.R.;Ham, J.E.;LeBouf, R.F.;Martin, S.B. Jr.;Duling, M.G.;Bowers, L.N.;Knepp, A.K.;de Beer, D.J.;du Plessis, J.L.
    • Safety and Health at Work
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    • v.10 no.2
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    • pp.229-236
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    • 2019
  • Background: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. Methods: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. Results: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from $4.1{\times}10^{10}$ (Ultem filament) to $2.2{\times}10^{11}$ [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (${\mu}g/min$) ranged from $1.9{\times}10^4$ (acrylonitrile butadiene styrene and polycarbonate) to $9.4{\times}10^4$ (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open ($2.3{\times}10^{10}number/min$) than when the lid was closed ($1.5-5.5{\times}10^9number/min$); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. Conclusion: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.

Prevalence and associates of obesity and overweight among school-age children in a rural community of Thailand

  • Nonboonyawat, Teechaya;Pusanasuwannasri, Wuttipat;Chanrat, Nattanon;Wongthanavimok, Natta;Tubngern, Danutanut;Panutrakul, Piengkwan;Mungthin, Mathirut;Nivesvivat, Thirapa;Hatthachote, Panadda;Rangsin, Ram;Piyaraj, Phunlerd
    • Clinical and Experimental Pediatrics
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    • v.62 no.5
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    • pp.179-186
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    • 2019
  • Purpose: Information about overweight and obesity among students in rural areas of Thailand is limited. Therefore, we aimed to determine overweight and obesity prevalences and associated factors among school-aged children in a rural community of Thailand. Methods: We selected 9 public schools through cluster sampling in 2 provinces located in central Thailand in 2016. Anthropometric measurements were measured using standard techniques, classified as overweight (>1 standard deviation [SD]) and obese (>2 SD) with respect to their age and sex using 2007 World Health Organization reference charts. Standardized questionnaires on risk factors were sent to parents to be completed together with their child. Results: Among 1,749 students, 8.98% had overweight and 7.26% had obesity. Mean age (range) was 11.5 years (5-18 years). Independent factors associated with overweight and obesity included primary school student (reference as secondary school) (adjusted odds ratio [aOR], 2.25; 95% confidence interval [CI], 1.24-4.08; P=0.07), mother's body mass index (aOR, 1.07; 95% CI, 1.02-1.12; P=0.001), self-employed father (aOR, 1.99; 95% CI, 1.12-3.55; P=0.018), number of siblings (aOR, 0.61; 95% CI, 0.47-0.81; P=0.001), having sibling(s) with obesity (aOR, 1.82; 95% CI, 1.20-2.77; P=0.005), more than one (aOR, 7.16; 95% CI, 2.40-21.32; P<0.001), consuming 2-3 ladles of rice/meal (aOR, 2.14; 95% CI, 1.38-3.32; P=0.001), consuming >3 ladles of rice/meal (aOR, 2.69; 95% CI, 1.11-6.46; P=0.27), watching <2 hours of television/day (aOR, 2.18; 95% CI, 1.19-4.01; P=0.012), and watching >2 hours of television/day (aOR, 2.60; 95% CI, 1.36-4.96; P=0.004). Conclusion: Many sociodemographic, dietary, and behavioral factors were related to overweight and obesity among school-aged children not only in urban but also rural communities of Thailand.

Microbial Metagenome of Airborne Particulate Matter: Methodology, Characteristics, and Influencing Parameters (대기입자상물질의미생물메타게놈: 분석방법, 특성및영향인자)

  • Kang, Sookyung;Cho, Kyung-Suk
    • Microbiology and Biotechnology Letters
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    • v.50 no.2
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    • pp.165-192
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    • 2022
  • The microbial metagenome characteristics of bioaerosols and particulate matter (PM) in the outdoor atmospheric environment and the effects of climate and environmental factors on the metagenome were analyzed. The concentrations of bacteria and fungi in bioaerosols and PM were determined by sampling different regions with different environmental properties. A variety of culture-independent methods were used to analyze the microbial metagenome in aerosols and PM samples. In addition, the effects of meteorological and environmental factors on the diversity and metagenomes of bacteria and fungi were investigated. The survival, growth, and dispersal of the microorganisms in the atmosphere were markedly affected by local weather conditions and the air pollutant concentration. The concentration of airborne microorganisms increased as the temperature increased, but their concentration decreased in summer, due to the effects of high temperatures and strong ultraviolet rays. Humidity and microbial concentration were positively correlated, but when the humidity was too high, the dispersion of airborne microorganisms was inhibited. These comprehensive data on the microbial metagenome in bioaerosols and PM may be used to understand the roles and functions of microorganisms in the atmosphere, and to develop strategies and abatement techniques to address the environmental and public health problems caused by these microorganisms.

The Relationship among Leisure Experience, Exercise flow Adherence of Senior in Fitness Center (스포츠센터 노인 운동 프로그램 참여자의 여가경험과 여가몰입 및 운동만족의 관계)

  • Lee, Seung-Bum
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.2
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    • pp.159-167
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    • 2021
  • The main purpose of this study is to closely investigate the constructive relationship between leisure satisfaction, leisure ability, exercise satisfaction, and consistent motor behavior patterns of the elderly's participation in leisure life sports. In order to achieve this, we surveyed and utilized the sampling of conveniences that selected Yongin and Seongnam city in Gyeonggi-do sports clubs, and accumulated samples of the elderly in living sports. The sample size was 239 elderly people. Based on this, according to the purpose of the study, statistical techniques, spss 23.0, and amos programs were used for analysis. The satisfaction analysis used in the research for a data analysis includes frequency analysis, exploatory factor analysis, confirmatory facor analysis, reliability analysis, correnlation analysis and structure equation model analysis. The research has drawn the following conclusions, based on the above mentioned research method and its procedures: First, it affects the satisfaction of the leisure satisfaction movement. Second, leisure ability affects exercise satisfaction. Third, exercise satisfaction affects the consistent exercise persistence and immersion satisfaction of exercise. As a result, it can be seen that the leisure immersion according to the experience of leisure competence has an effect on the satisfaction of the exercise. As a result, and the continuation of the exercise.

A Study on the Structural Relationship of Achievement Goal Propensity, Sports Confidence, and Perceived Performance Using the Mentoring System of High School Leaders (고등학교 지도자의 멘토링시스템을 활용한 성취목표성향, 스포츠 자신감 및 인지된 경기력의 구조적 관계 고찰)

  • Kim, Seon-Il;Cho, Ki-Jung;Han, Dong-Sung
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.6
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    • pp.153-163
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    • 2021
  • This study has a main purpose that closely examines the structural relationship among A Study on the Structural Relationship of Achievement Goal Propensity, Sports Confidence, and Perceived Performance Using the Mentoring System of High School Leaders. In order to achieve it, the sample from high school student participants were accumulated by using convenience sampling that chose taekwondo championship in national. The samples were 500 people. and we excluded unsuitable sheet like that were decided as untruthful one and an omission and unclear. So the final samples were 465 people. On the basis of that, The statistical techniques, spss 24.0 and amos 24.0 program have been used for the analysis as per research purpose. The statistical analysis used in the research for a data analysis includes frequency analysis, confirmatory factor analysis, reliability analysis, correlation analysis, and structure equation model analysis. The research has drawn the following conclusions, based on the above mentioned research method and its procedures: First, The mentoring influences the achievement goal orientation. Second, The mentoring influences the sport confidence. Third, The achievement goal orientation influences the perceived performance. Fourth, The sport confidence influences the perceived performance.