• Journal of Appropriate Technology
• /
• v.6 no.2
• /
• pp.136-145
• /
• 2020

Agriculture is the backbone of the economy of most developing countries. In these countries, agriculture or farming is mostly done manually with little integration of machinery, intelligent systems and data monitoring. Irrigation is an essential process that directly influences crop production. The fluctuating amount of rainfall per year has led to the adoption of irrigation systems in most farms. The absence of smart sensors, monitoring methods and control, has led to low harvests and draining water sources. In this research paper, we introduce a 433 MHz Radio Frequency and 2G based Smart Irrigation Meter System and a water prepayment system for rural areas of Tanzania with no reliable internet coverage. Specifically, Ngurudoto area in Arusha region where it will be used as a case study for data collection. The proposed system is hybrid, comprising of both weather data (evapotranspiration) and soil moisture data. The architecture of the system has on-site weather measurement controllers, soil moisture sensors buried on the ground, water flow sensors, a solenoid valve, and a prepayment system. To achieve high precision in linear and nonlinear regression and to improve classification and prediction, this work cascades a Dynamic Regression Algorithm and Naïve Bayes algorithm.

• Journal of agricultural medicine and community health
• /
• v.47 no.4
• /
• pp.220-228
• /
• 2022

Objective: glucometer is one of POCT(point-of-care testing) devices used by EMS. Accurate measurement value is important for patient decision making. Quality control is necessary for this, but most EMS are still using glucometer without quality control it. Therefore, management status and quality control status of glucometers used by 119 paramedics waswere investigated. Methods: 6 and 8 of glucometers and blood glucose test strips were submitted from 4 safety centers in 2010 and 8 safety centers in 2012, respectively. Glucometers submitted by local safety centers were analyzed in 2010 and 2012. The control glucometer, which was well managed at A University Hospital, was assumed to be accurate for at blood glucose measurement. Glucose values of various quality control materials control solutions were measured and analyzed using linear regression and Pearson's correlation test. Error rates were obtained via error tolerance range required by the 2011 ISO(International Organization for Standardization) guideline. For statistics, Excel and MedCalC programs were used. Results: mong 14 safety centers in the region, 4 centers(28.5%) in 2010 and 8 centers(57.1%) in 2012 submitted 6 and 8 glucometers. In the first evaluation in 2010, 2 out of 6(33.3%) glucometers were untestable due to error, and 45 out of 6(66.683.3%) blood glucose test strips' validity were expired. In the second evaluation in 2012, 1 out of 8(13.5%) glucometers were untestable due to lack of battery, and 2 out of 8(25%) blood glucose test strips' validity were expired. All correlation coefficients were above 0.989 in 2010 and above 0.997 in 2012. Error rates were generally high when using expired blood glucose test strips. Conclusion: Among 119 paramedics' guideline, quantity and operation status of POCT devices are well managed, but quality control is not. Therefore, it is necessary to add management status and quality control status of POCT devices to the EMS' field work guideline.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.4
• /
• pp.785-789
• /
• 2021

Paprika productivity is different even in the same quality greenhouse and in the same region. These differences are known to due to differences in various environmental factors. This study was conducted to investigate the difference in the level of various environmental factors between high-productivity (HPF) and low-productivity (LPF) greenhouses. The largest difference between the two greenhouses in the daily or weekly average values of major environmental factors was the CO₂ concentration, but the LPF was higher than the HPF, so it was not determined as a factor for the difference in productivity. Correlation analysis among 14 environmental factors showed a high correlation among irradiation or related factors in moisture. The regression coefficients of the linear regression model between vapor pressure deficit and relative humidity were -0.0202kpa in HPF and -0.0262kpa in LPF. In particular, in February and March, the vapor pressure deficit in LPF was 1.5kpa or more, and the cumulative vapor pressure deficit compared to the cumulative irradiation at the early period of cultivation increased rapidly. The reason for the low productivity in LPF is thought to be that the plant was affected by moisture stress due to high vapor pressure deficit and transpiration under low irradiation conditions in the early period of cultivation and in winter.

• Tunnel and Underground Space
• /
• v.33 no.1
• /
• pp.57-69
• /
• 2023

In this study, we simulated induced seismicity in the Groningen natural gas reservoir using 2D hydro-mechanical coupled discrete element modelling (DEM). The code used is PFC2D (Particle Flow Code 2D), a commercial software developed by Itasca, and in order to apply to this study we further developed 1)initialization of inhomogeneous reservoir pressure distribution, 2)a non-linear pressure-time history boundary condition, 3)local stress field monitoring logic. We generated a 2D reservoir model with a size of 40 × 50 km² and a complex fault system, and simulated years of pressure depletion with a time range between 1960 and 2020. We simulated fault system failure induced by pressure depletion and reproduced the spatiotemporal distribution of induced seismicity and assessed its failure mechanism. Also, we estimated the ground subsidence distribution and confirmed its similarity to the field measurements in the Groningen region. Through this study, we confirm the feasibility of the presented 2D hydro-mechanical coupled DEM in simulating the deformation of a complex fault system by hydro-mechanical coupled processes.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.6A
• /
• pp.835-842
• /
• 2008

The response surface method (RSM) is widely adopted for the structural reliability analysis because of its numerical efficiency. However, the RSM is still time consuming for large-scale applications and sometimes shows large errors in the calculation of sensitivity of reliability index with respect to random variables. Therefore, this study proposes a new RSM in which moving least squares (MLS) approximation is applied. Least squares approximation generally used in the common RSM gives equal weight to the coefficients of the response surface function (RSF). On the other hand, The MLS approximation gives higher weight to the experimental points closer to the design point, which yields the RSF more similar to the limit state at the design point. In the procedure of the proposed method, a linear RSF is constructed initially and then a quadratic RSF is formed using the axial experimental points selected from the reduced region where the design point is likely to exist. The RSF is updated successively by adding one more experimental point to the previously sampled experimental points. In order to demonstrate the effectiveness of the proposed method, mathematical problems and ten-bar truss are considered as numerical examples. As a result, the proposed method shows better accuracy and computational efficiency than the common RSM.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.3C
• /
• pp.187-196
• /
• 2008

An earthquake of magnitude 5.0 occurred at Ssang-gye-sa, a Buddhist temple in Jirisan, located near the southern border of the Korean peninsula on 4 July 1936. It resulted in severe damage of several buildings and structures in Ssang-gye-sa. Particularly, the top component of a five-story stone pagoda in the temple was tipped over and fell down during the earthquake. This earthquake damage case would be usefully applied to estimating the intensity of ground motion in the Korean peninsula, a moderate seismicity region, where strong motion has never been recorded with the exception of historic seismic events. In order to estimate the local site effects and the corresponding ground motion at Ssang-gye-sa site, intensive site investigations including borehole drilling and in-situ seismic tests such as crosshole and SASW tests were performed in the temple area. Based on the site characteristics, site-specific seismic response analyses using various input motions were conducted for a representative Ssang-gye-sa site by means of both one-dimensional equivalent-linear and nonlinear methods with six input rock outcrop acceleration levels ranging from 0.044g to 0.220g. The resultant site-specific seismic responses indicated the amplified ground motions in the short-period range near the site period of Ssang-gye-sa. Furthermore, the intensity on rock outcrop of the 1936 Jirisan earthquake was estimated by making a comparison between the site responses analysis results in this study and the full-scaled seismic test of pagoda model in the prior study.

• Journal of Nutrition and Health
• /
• v.57 no.1
• /
• pp.88-104
• /
• 2024

Purpose: High-sensitivity C-reactive protein (hs-CRP) is primarily synthesized in the liver upon stimulation of infectious disease cytokines, such as interleukin-6 (IL-6), and is used as a biological marker of systemic inflammation. Previous studies reported that hs-CRP is closely related to diet and abdominal obesity. Furthermore, a dietary score favoring the consumption of vegetables, fruits, and whole grains over meat and saturated fat reduced inflammation and decreased the prevalence of obesity and abdominal obesity. Nevertheless, no studies have examined whether hs-CRP mediates the relationship between dietary scores and abdominal obesity, and research on the Korean Healthy Eating Index (KHEI) is lacking. Therefore, the present study examined the association between the KHEI and abdominal obesity and the mediating effect of hs-CRP. Methods: In total, 17,770 adults aged ≥19 years were included in the study using the Korea National Health and Nutrition Examination Survey 2015-2018. KHEI was developed to assess the overall diet quality of Korean adults. Multivariable linear and logistic regression analyses assessed the relationship between KHEI, hs-CRP, and abdominal obesity. The mediation analysis with the bootstrapping method was performed using SAS MACRO. Results: Among women, the odds ratio (OR) of abdominal obesity prevalence was lower in the highest KHEI compared to the lowest KHEI after adjusting for age, body mass index, educational level, income level, occupational status, marital status, household type, region type, alcohol consumption, smoking status, physical activity, total energy intake, and hsCRP (OR 0.744, 95% confidence interval 0.598-0.926). The association between KHEI and abdominal obesity was partially mediated via hs-CRP, and the mediated proportion was 68.7% in men and 38.1% in women. Conclusion: A substantial relationship was observed between the KHEI and abdominal obesity among females. Moreover, according to the KHEI, abdominal obesity may be mediated partially by hs-CRP.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.40 no.3
• /
• pp.135-141
• /
• 2024

Purpose: The purpose of this study was to investigate the accuracy of image merging of an intraoral scan of an edentulous arch to a facial scan using wax rim and markers. Materials and Methods: For registration of oral scan to face scan, a wax rim with markers was made. The markers were cuboid and divided into four groups according to size (5, 10 mm) and attachment location (midline, canine region). The evaluation of registration accuracy was compared with a standard created using cone-beam computed tomography data. Anterior linear variation of the edentulous arch and the 3D variation of the overall arch were measured. Kruskal-Wallis test and Mann-Whitney U test were used for statistics, and the significance level was set at 0.05 and evaluated under Bonferroni correction (0.05/6 = 0.083). Results: In the anterior deviation and global deviation results, there was no statistically significant difference in the oral scan position displacement values between the 5 mm and 10 mm groups. When the midline marker was used, the intraoral scan position displacement value was significantly lower than when only the canine marker was used. Conclusion: Marker attached wax rim can be used for image matching between facial and intraoral scans of the edentulous arch. Marker location at the middle area increases the accuracy of image matching.

• Radiation Oncology Journal
• /
• v.9 no.1
• /
• pp.131-141
• /
• 1991

A comprehensive set of dosimetric measurements has been made on the Varian Clinac 1800 15 MV photon beam. Beam quality, percentage depth dose, dose in the build up region, output, symmetry and flatness, transmission through iead (Cerrobend), tray attenuation, isodose curves for the open and wedged fields were measured using 3 dimensional water phantom dosimetry system (including film densitometer system) and polystyrene phantoms. These dosimetric measurements sufficiently characterized the beam to permit clinical use. The depth dose characteristics of photon beam is $d_{max}$ of 3.0 cm and percentage depth dose of $76.8\%$ at 10 cm,100 cm source-surface distance, field size of $10\times10\;cm^2$ for 15 MV X-ray beam. The Output factors ranged 0.927 for $4\times4\;cm^2$ field to 1,087 for $35\times35\;cm^2$ field. The build-up level of maximum dose was at 3.0 cm and surface dose was approximately $15.5\%$ for a field size $10\times10\;cm^2$ The stability of output is $within\pm1\%$ and flatness and symmetry are $within\pm3\%$. The half value thickness (HVL) of lead is 13 mm, which corresponds to an attenuation coefficient of $0.053\;mm^{-1}$. These figures compare facorably with the manufacturesr`s specifications.

• Journal of the Korean earth science society
• /
• v.28 no.4
• /
• pp.478-490
• /
• 2007

With groundwater data of seawater intrusion monitoring network in coastal areas of Korea's main land, we analyzed types of seawater intrusion through the coastal aquifer. The data including groundwater level, temperature and electrical conductivity obtained from 45 monitoring wells at 25 watershed regions were evaluated. Based on statistical analysis, correlation analysis and variation type analysis, groundwater levels were mainly affected by rainfall and artificial pumping. About 78% of the monitoring wells showed average temperature higher than $15^{\circ}C$ and about 58% of them showed minimum variations less than $0.2^{\circ}C$. Electrical conductivities showed a large magnitude of variation and irregular characteristics compared with groundwater levels and temperatures. Average electrical conductivities lower than $2,000\;{\mu}S/cm$ were observed at 28 monitoring wells while those of higher than $10,000\;{\mu}S/cm$ were done at 9 monitoring wells. From the cross-correlation analysis, groundwater levels were mostly affected by precipitation while temperature and electrical conductivity showed very low correlation. Meanwhile tidal variations strongly affected the groundwater levels comparing to precipitation. We classified the long-term monitoring data according to variation types such as constant process, linear trend, cyclic variation, impulse, step function and ramp. Impulse type was dominant for variations of groundwater level, which was largely affected by rainfall or artificial pumping, the constant process was dominant for temperature. Compared with groundwater level and temperature, electrical conductivities showed various types like linear trend, step function and ramp. According to the discrepancy of variation characteristics for monitoring data at each well in the same region, periodical analysis of monitoring data is essentially required.