• Title/Summary/Keyword: quality control tests

Search Result 542, Processing Time 0.029 seconds

Water Level and Quality Variations of CO2-rich Groundwater and Its Surrounding Geology in the Chungju Angseong Spa Area, South Korea: Considerations on Its Sustainability (충주 앙성지역 탄산천의 수위/수질 변동과 주변 지질 특성: 탄산천의 지속가능성에 대한 고찰)

  • Moon, Sang-Ho;Kee, Weon-Seo;Ko, Kyung-Seok;Lee, Cholwoo;Choi, Hanna;Koh, Dong-Chan
    • Economic and Environmental Geology
    • /
    • v.55 no.5
    • /
    • pp.477-495
    • /
    • 2022
  • This study examined the sustainability of CO2-rich water by analyzing the water level and water quality change pattern with the amount of its use in Angseong area, Chungju. The origin and supply of CO2 component were discussed in consideration of 87Sr/86Sr ratio, occurrence of CO2-rich fluid inclusions in nearby W-Mo deposits and other surrounding geological characteristics. According to the data from 1986 to 2017, the depth of the water level of CO2-rich water was significantly lowered in the late period (2009-2015) than in the early period (1986-1992) of the development of hot spa wells, and the optimal yields for pumping tests also showed a tendency to gradual decrease. Concentrations of CO2 component also decreased continuously in the later stages compared to the early stages of development, but it has been stable since 2012. It is inferred that the geological environment related to forming W-Mo quartz vein deposits (0.5×1.5×several km) around the study area are largely involved in the origin and supply of CO2 component, and the supply of CO2 component is not infinitely supplied from deep current magma activity. Rather, since it is finitely supplied from a restricted subsurface region formed in the past geological period, it is necessary to efficiently control its use in order to maintain the sustainability of CO2-rich water in the study area.

Individual Bioequivalence Tests under 3 X 2 Design (3 X 2 교차설계법에서 개인 생물학적 동등성 검정)

  • Jung, Gyu-Jin;Lim, Nam-Kyoo;Park, Sang-Gue
    • The Korean Journal of Applied Statistics
    • /
    • v.23 no.1
    • /
    • pp.139-150
    • /
    • 2010
  • In recent years, more generic drug products became available. The current regulation for assessing the bioequivalence of two drug formulations is based on the concept of average bioequivalence. This approach has been indicated to be insufficient for assessing switchability between two drug formulations and US FDA has adopted individual bioequivalence as one of the bioequivalence criterion since 2001. The US FDA recommends that individual bioequivalence be assessed based on $2\;{\times}\;4$ crossover design, while a $2\;{\times}\;3$ crossover design may be used as an alternative design to reduce the length and cost of the study. In this paper, a statistical procedure for assessment of individual bioequivalence under $3\;{\times}\;2$ crossover designs is proposed and some statistical points are discussed with $2\;{\times}\;3$ crossover design and $2\;{\times}\;3$ extra-reference design through simulation studies.

Helicobacter pylori and Pancreatic Cancer Risk: a Meta-analysis Based on 2,049 Cases and 2,861 Controls

  • Wang, Yin;Zhang, Fu-Cheng;Wang, Yao-Jun
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.11
    • /
    • pp.4449-4454
    • /
    • 2014
  • Aim: Helicobacter pylori (H. pylori) have been considered as a risk factor for many cancers. We conducted this meta-analysis to clarify the association between H. pylori infection and the risk of pancreatic cancer. Methods: We searched the Medicine/Pubmed and Embase databases, studies about the association between H. pylori infection and pancreatic cancer published up to Jan.2014 were included. Finally, a total of 9 studies were used for this a meta-analysis. The odds ratios (ORs) and 95% confidence interval (95%CI) of H. pylori infection on pancreatic cancer with respect to control groups were evaluated. Two authors independently assessed the methodological quality and extracted data. This meta-analysis was conducted using software, state (version 12.0) to investigate heterogeneity among individual studies and to summarize the studies. Using the fixed-effects or random-effects model, depending on the absence or presence of significant heterogeneity. Sensitivity analysis was performed to assess the influence of each individual study on the pooled ORs by omitting a single study each time. Publication bias was evaluated by funnel plot, using Egger's and Begg's tests. Results: There was no significant association between H. pylori infection and pancreatic cancer risk in the summary ORs,(OR=1.06, 95%CI: 0.74-1.37) through the random-effect method, but heterogeneity among studies was significant ($I^2$=58.9%), so we put the studies into two subgraphs (eastern and western). The results about western (OR=1.14 95%CI:0.89, 1.40) showed heterogeneity among the western countries of $I^2$=6.6%, with no significant association between Hp+ and pancreatic cancer, but the eastern countries (OR=0.62, 95%CI:0.49, 0.76), $I^2$=0, suggested that decreasing pancreas-cancer risk in subjects with Hp+ infection. Simultaneously, 7 studies examined CagA+ strains was (OR=0.84 95%CI:0.63, 1.04), $I^2$=36% with the random-effect method, subgraphs indicated that CagA+ could decrease the risk of pancreatic cancer in the eastern subjects (OR=0.66, 95%CI:0.52-0.80), but the association was not statistically significant in the western subjects (OR=0.95, 95%CI:0.73, 1.16). Conclusion: Hp+ and CagA+ infection are associated with a decreased risk of pancreatic cancer in eastern populations but have no significant associations in western countries.

Experimental Study on Flexural Behavior of PSC I Girder and the Effect of External Prestressing (PSC I합성 거더의 휨 거동 및 외부 강선 보강효과에 관한 실험 연구)

  • Lee, Byeong-Ju;Park, Jae-Guen;Kim, Moon-Young;Shin, Hyun-Mock;Park, Chang-Ho
    • Journal of the Korea Concrete Institute
    • /
    • v.19 no.6
    • /
    • pp.755-762
    • /
    • 2007
  • For the evaluation of the load carrying capacity of the deteriorated PSC I girder bridge in service load state and the verification of the grade to the reinforcement effect of actual bridge strengthened by external prestressing tendons, the field test using vehicles is applied widely. Because this teat was executed in elastic range, the investigation of the characteristics of behavior caused by live load is only available. And it is impossible to estimate load carrying capacity in limit state and nonlinear behavior after that a crack is appeared. In this study, the 27-year-old prestressed concrete girder bridge is used and various load tests are performed, so we evaluate the behavior characteristics of the bridge in service load state and ultimate load state, and estimate the load carrying capacity of bridge. In addition, the artificial damages are induced from cutting internal tendons, and external tendons is added to strengthen it as much as vanished internal tendons. Next we compare the damage state with the strengthening state. In case of the application of external prestressing method to PSC I girder bridge, the present experiment result may decide more exactly the load carrying capacity of actual bridge, the amount for reinforcement, and the standard of quality control etc. at reinforcement work.

Changes of Field Establishment and Growth in Cover Crops Sown at Different Times (파종 시기에 따른 피복작물의 월동 후 생존과 생장 변화)

  • Lee, Ji-Hyun;Shim, Sang-In;Kang, Chung-Kil;Jee, Hyeong-Jin;Lee, Hyeon-Bok;Lee, Byung-Mo
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.54 no.2
    • /
    • pp.218-224
    • /
    • 2009
  • In organic fanning systems, integration of cover crops into cropping system are recommended to improve the soil quality, to prevent soil erosion, and to provide biological control of weeds. The aim of the present study was to evaluate the optimal seeding dates of major cover crops. To know optimal seeding dates, crimson clover, alfalfa, rye and hairy vetch were sown on 20. Sep., 27. Sep., 4. Oct., 11. Oct., 18. Oct., 25. Oct. Rye could germinate and grow well in all the tested sowing dates. Hence, it was concluded that the sowing of rye could be conducted later in fall or more earlier in spring than any other cover crops tested in this study. Growth and ground covering capacity were significantly decreased by late sowing in alfalfa and crimson clover. For safe overwintering, alfalfa and crimson clover should be sown before late September. Similarly, field emergence of hairy vetch was found to be sensitive to soil temperature, however, its growth and ground covering capacity after overwintering was enough to compensate the delay in sowing. Germination tests in laboratory revealed that hairy vetch grew faster at $25^{\circ}C$ compared to $20^{\circ}C$. The result suggested that germination and growth rate of hairy vetch was rapidly decreased at low temperature. Therefore, it is recommended that hairy vetch should be sown as soon as possible in September for improving stand establishment after overwintering.

A Cross-sectional Study of Deficiency-Excess Pattern Identification with Blood Cytokines and Characteristics of Patients with Asthma (천식환자 허실변증별 혈액 싸이토카인 및 임상적 특성에 관한 단면적 연구)

  • Yu, Chang-hwan;Kang, Sung-woo;Hong, Sung-eun;Kim, Kwan-il;Lee, Beom-joon;Jung, Hee-jae
    • The Journal of Internal Korean Medicine
    • /
    • v.41 no.4
    • /
    • pp.583-598
    • /
    • 2020
  • Objective: The aims of this study were to analyze deficiency-excess pattern identification and to compare the blood cytokines in patients with asthma. Methods: A total of 112 patients with asthma who met the inclusion and exclusion criteria were divided into deficiency syndrome and excess syndrome groups. Blood was examined for eotaxin, interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF)-α. The Quality of Life Questionnaire for Adult Korean Asthmatics (QLQAKA), a Visual Analogue Scale (VAS), and heart rate variability (HRV) tests were administered to both groups. Results: Pattern identification divided the 112 patients into two categories: a deficiency syndrome group (N=52) and an excess syndrome group (N=60). Analysis of blood cytokines showed higher levels of IL-4, IL-5, and IL-13 in the deficient pattern than in the excess pattern group, but the difference was not statistically significant. Analysis of the HRV revealed a significantly higher mean value for the very-low-frequency (VLF) and high-frequency (HF) bands in the deficiency than in the excess syndrome group. The morbidity duration was longer in the deficiency than in the excess syndrome group, but the difference was not statistically significant. Analysis of the QLQAKA and VAS scores showed a negative correlation, whereas BMI and VAS showed a positive correlation. Conclusions: Levels of blood cytokines, including eotaxin, IL-1β, IL-4, IL-5, IL-6, IL-13, and TNF-α, did not differ statistically between the deficiency and excess syndrome groups. The development of a more accurate asthma-specific pattern identification tool would be useful in asthma control.

Evaluation of Vibration and Structural Performance of an Innovative Sliding Step Steel Stair Using Full-Scale Mock-up Test (실물대 목업실험에 의한 슬라이딩스텝 철골계단의 진동 및 구조성능 평가)

  • Kim, Sung Yong;Lee, Cheol Ho;Kim, Na Eun;Cho, Sung Sang;Chung, Woon Ok
    • Journal of Korean Society of Steel Construction
    • /
    • v.26 no.6
    • /
    • pp.511-522
    • /
    • 2014
  • In this study, an innovative steel stair system is presented which enables rapid erection and high quality control in both residential and office building construction. This system features two lightweight steel stringers of box shape, bolted connections easy to absorb construction tolerance, and stair steps movable transversely (or sliding steps) such that the work space needed for concrete stairway wall could be easily provided. In this type of stairway system, other than providing robust connecting details, ensuring vibration performance is especially important since this system may be vibration-sensitive due to lightweight nature and/or probable low damping. To tackle these issues, a series of full-scale mock-up tests were conducted by using box-shape stringer members with or without concrete-fill. The connection system was shown to be sufficiently stiff and strong, or it remained elastic even under the 160% of service load level. Among the seven stringer alternatives, five exhibited satisfactory vibration performance according to the related North American and European acceptance criteria.

Improvement of Validity and Efficiency for Detection of Cryptosporidium Ocysts and Giardia Cysts in Environmental Water Samples (환경수 중 크립토스포리디움 오시스트 및 지아디아 시스트 검출의 정확도 및 회수율 향상을 위한 연구)

  • 이목영;조은주;김도연;변승헌;이의광;오세종;안승구
    • Korean Journal of Microbiology
    • /
    • v.39 no.1
    • /
    • pp.27-35
    • /
    • 2003
  • No currently available methods to monitor pathogenic protozoa, Cryptosporidium and Giardia in environmental water come close to acceptable sensitivity, specificity and reproducibility, and so it has to be accompanied by thorough quality control and performance evaluation to credibly predict the distribution of them. We collected surface water samples from the Han River and spiked our prepared (oo)cysts, determined Matrix Spike recoveries using USEPA Method 1623 and considered what factors influence MS recovery and validity. As a result, average 46% of spiked oocysts and 60% of spike cysts were recovered, but repetitive sampling and statistical approach seemed to be necessary to determine the environmental pollution level of two protozoa as their variation coefficients was so much as 35oio and 26%. And MS recoveries with two acid dissociations during immunomagnetic separation were improved more 10% than that with one dissociations and the use of spiked suspension enumerated by flow cytometry instead of manual preparation enhanced the validity and reliability in spiking tests. Because fluorescence characteristics of (oo)cysts stained on well slides with FITC-labeled monoclonal antibodies and DAPI was not always same, well Elides from spiked field samples were helpful to evaluate the performance of staining. We found many (oo)cyst-like objects with typical fluorescence, not (co)cysts, from the Han River water samples, and then it was concluded that nuclei staining by DAPI (4',6-diamidino-2-phenylindole) and examination by Differential Interference Contrast Microscope should be critical for valid identification.

The Integrated Measurement and Analysis System for T-DMB (T-DMB를 위한 통합 측정 및 분석 시스템)

  • Kim, Sang-Hun;Kim, Young-Min;Kim, Man-Sik;Kim, Gyu-Young
    • Journal of Broadcast Engineering
    • /
    • v.12 no.1 s.34
    • /
    • pp.11-27
    • /
    • 2007
  • T-DMB(Terrestrial-Digital Multimedia Broadcasting) for portable and mobile broadcasting service was officially launched in the metropolitan area of Korea in December 2005. The development of interactive data services and the expansion of T-DMB network have been now progressed, and the regional T-DMB broadcasters will be selected in the near future. Although it is important to evaluate service area and reduce a fringe area for optimizing RF coverage of T-DMB, there was no professional system to support those works, and therefore lots of resources in budget, manpower and time were required. The measurement considering characteristics of SFN(Single Frequency Network) is essential in the implementation of T-DMB network which needs to control synchronization, spacing and output power of transmitters. In addition, mobile measurement, enough measured parameters for many-sided analysis of reception quality, efficient management of enormous measured data and representation of measured results on the electronic map are also important in evaluating service area. In this paper, we derived requirements for a new measurement system in T-DMB by considering the above details, and we proposed and developed an integrated measurement and analysis system. The developed system was applied to the implementation of T-DMB network of KBS and field tests, and it proved its efficiency and accuracy in result.

Analysis of the relationship between lifestyle habits and glycosylated hemoglobin control based on data from a Health Management Plan

  • Wang, Ya-Chun;Wang, Chi;Shih, Ping-Wen;Tang, Pei-Ling
    • Nutrition Research and Practice
    • /
    • v.14 no.3
    • /
    • pp.218-229
    • /
    • 2020
  • BACKGROUND/OBJECTIVES: Type 2 Diabetes mellitus (T2DM) is a hereditary disease that is also strongly dependent on environmental factors, lifestyles, and dietary habits. This study explored the relationship between lifestyle habits and glycosylated hemoglobin management in T2DM patients to provide empirical outcomes to improve T2DM management and patient health literacy. SUBJECTS/METHODS: This study enrolled 349 diabetic patients with more than 5 care visits to a Diabetes Mellitus care network under the Health Management Plan led by Taiwan Department of Health (DOH). Based on relevant literature, an Outpatient Record Form of Diabetes Mellitus Care was designed and lipid profile tests were conducted for data collection and analysis. RESULTS: When modeling the data, the results showed that the odds for HbA1c > 7.5% in T2DM patients duration over 10 years was 3.785 (P = 0.002) times that in patients with disease duration of fewer than 3 years. The odds of HbA1c > 7.5% in illiterate patients was 3.128 (P = 0.039) times that in patients with senior high school education or above. The odds of HbA1c > 7.5% in patients with other chronic illness was 2.207 (P = 0.019) times that in participants without chronic illness. Among 5 beneficial lifestyle habits, the odds of HbA1c > 7.5% in patients with 2 or 3 good habits were 3.243 (P = 0.003) and 3.424 (P = 0.001) times that in patients with more than 3 good habits, respectively. CONCLUSION: This empirical outcome shows that maintaining a good lifestyle improves T2DM management and patients' knowledge, motivation, and ability to use health information. Patients with longer disease duration, education, or good lifestyle habits had optimal HbA1c management than those in patients who did not. Thus, effective selfmanagement and precaution in daily life and improved health literacy of diabetic patients are necessary to increase the quality of T2DM care.