• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.34 no.2
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• pp.139-147
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• 2024

Objective: The introduction of government support programs for small businesses in 1993 aimed to enhance awareness and capabilities in industrial health management among small business proprietors, marking a continuous expansion over the past three decades. Despite this growth, there has been a conspicuous absence of comprehensive evaluations regarding the efficacy of these initiatives. In response, this study endeavors to conduct a thorough policy evaluation. Method: Through a meticulous approach, we conducted an analysis of in-depth interviews with eight individuals possessing expertise in the administration of government support programs for small businesses. These interviews were sourced from personnel affiliated with government ministries and public agencies. Results: In the analysis, it was found that small-scale business government support programs operate primarily based on quantity rather than receiving support from business owners regarding their necessity or utility. Consequently, these programs have failed to yield substantial effects on altering the perception of business owners or improving the working environment within the businesses. Conclusion: This study assumes significance in its capacity to discern intricate procedural challenges in program implementation, which often elude quantitative scrutiny. Furthermore, it provides pivotal insights for enhancing government support programs.

• Smart Structures and Systems
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• v.33 no.4
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• pp.291-300
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• 2024

Uncertainty of the model, system delay and drive dynamics can be considered as normal uncertainties, and the main source of uncertainty in the seismic control system is related to the nature of the simulated seismic error. In this case, optimizing the management strategy for one particular seismic record will not yield the best results for another. In this article, we propose a framework for online management of active structural management systems with seismic uncertainty. For this purpose, the concept of reinforcement learning is used for online optimization of active crowd management software. The controller consists of a differential controller, an unplanned gain ratio, the gain of which is enhanced using an online reinforcement learning algorithm. In addition, the proposed controller includes a dynamic status forecaster to solve the delay problem. To evaluate the performance of the proposed controllers, thousands of ground motion data sets were processed and grouped according to their spectrum using fuzzy clustering techniques with spatial hazard estimation. Finally, the controller is implemented in a laboratory scale configuration and its operation is simulated on a vibration table using cluster location and some actual seismic data. The test results show that the proposed controller effectively withstands strong seismic interference with delay. The goals of this paper are towards access to adequate, safe and affordable housing and basic services, promotion of inclusive and sustainable urbanization and participation, implementation of sustainable and disaster-resilient buildings, sustainable human settlement planning and manage. Simulation results is believed to achieved in the near future by the ongoing development of AI and control theory.

• Journal of the Korean earth science society
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• v.42 no.3
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• pp.247-263
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• 2021

Climate change has been accelerating in coastal waters recently; therefore, the importance of coastal environmental monitoring is also increasing. Chlorophyll-a concentration, an important marine variable, in the surface layer of the global ocean has been retrieved for decades through various ocean color satellites and utilized in various research fields. However, the commonly used chlorophyll-a concentration algorithm is only suitable for application in clear water and cannot be applied to turbid waters because significant errors are caused by differences in their distinct components and optical properties. In addition, designing a standard algorithm for coastal waters is difficult because of differences in various optical characteristics depending on the coastal area. To overcome this problem, various algorithms have been developed and used considering the components and the variations in the optical properties of coastal waters with high turbidity. Chlorophyll-a concentration retrieval algorithms can be categorized into empirical algorithms, semi-analytic algorithms, and machine learning algorithms. These algorithms mainly use the blue-green band ratio based on the reflective spectrum of sea water as the basic form. In constrast, algorithms developed for turbid water utilizes the green-red band ratio, the red-near-infrared band ratio, and the inherent optical properties to compensate for the effect of dissolved organisms and suspended sediments in coastal area. Reliable retrieval of satellite chlorophyll-a concentration from turbid waters is essential for monitoring the coastal environment and understanding changes in the marine ecosystem. Therefore, this study summarizes the pre-existing algorithms that have been utilized for monitoring turbid Case 2 water and presents the problems associated with the mornitoring and study of seas around the Korean Peninsula. We also summarize the prospective for future ocean color satellites, which can yield more accurate and diverse results regarding the ecological environment with the development of multi-spectral and hyperspectral sensors.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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• pp.126-134
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• 2001

Statistical approaches for analysis of data from the limited number of samples in ship building industry(SBI) collected by an industrial hygienist for checking compliance to an occupational standard were considered. Sampling for compliance usually has been guided by judgment selection, rather than true randomness, resulting in the creation of compliance samples which approximate a censored sample from the upper tail of the exposure distribution. Similar exposure groups(SEGs) including welding and painting process were established to assess representative values in each groups after reviewing the whole production line in SBI. For the convenient statistical approaches, the code has assigned to each SEGs. The descriptive statistics and probability plotting were used to yield the representative values in each SEGs. In the first step, SEGs of 558 were established from 5 ship building companies. The 38 SEGs showed the uncertainty are divided into each 5 companies and assessed the representative values again. The 44 SEGs in each companies was not showed the normal and lognormal distribution was analyzed each data. And also, recommendation was suggested to resolve the uncertainty in each groups.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.437-448
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• 2013

Hemipteran bugs, which were previously considered as secondary pests, have currently become important pests of numerous crops. Among them, Riptortus pedestris (Fabricius) is a major species that occurs in Korea, Japan, China, and South Asian countries. Riptortus pedestris infests leguminous crops like soybean, vetches, and red clover; fruit trees like persimmon and yuju; and grains like barley, foxtail millet, broomcorn, and sorghum. Riptortus pedestris causes the greatest damage to soybean, as it is the most suitable host for the bug. Feeding damage during pod formation significantly reduces the yield of soybean. Currently, 17 insecticides, including diazinon and etofenprox, are registered for the control of hemipteran bugs in Korea, and growers apply insecticides two to three times on a regular basis. Aggregation pheromone traps are widely used as a monitoring tool and partial control measure. The aggregation pheromone of R. pedestris attracts conspecific adults and nymphs and is used for food exploitation rather than sexual attraction. In addition, the pheromone serves as a kairomone for egg parasitoids such as Gryon japonicum (Ashmead) and Ooencyrtus nezarae Ishii. As a new method of pest management, nonviable host eggs were included in the pheromone trap to catch R. pedestris and propagate parasitoids. As a part of cultural practices, resistant soybean varieties with specific color and size of pod and control of flowering time through the alteration of planting date can be used. For the effective management of R. pedestris in the near future, development of cultural practices that can support natural control factors and the use of multiple control tactics are needed.

• Journal of The Korean Astronomical Society
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• v.49 no.3
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• pp.73-81
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• 2016

We report the characterization of a massive (m_p = 3.9±1.4M_jup) microlensing planet (OGLE-2015-BLG-0954Lb) orbiting an M dwarf host (M = 0.33 ± 0.12M_⊙) at a distance toward the Galactic bulge of $0.6^{+0.4}_{-0.2}kpc$, which is extremely nearby by microlensing standards. The planet-host projected separation is a⊥ ~ 1.2AU. The characterization was made possible by the wide-field (4 deg²) high cadence (Γ = 6 hr^–1) monitoring of the Korea Microlensing Telescope Network (KMTNet), which had two of its three telescopes in commissioning operations at the time of the planetary anomaly. The source crossing time t_* = 16 min is among the shortest ever published. The high-cadence, wide-field observations that are the hallmark of KMTNet are the only way to routinely capture such short crossings. High-cadence resolution of short caustic crossings will preferentially lead to mass and distance measurements for the lens. This is because the short crossing time typically implies a nearby lens, which enables the measurement of additional effects (bright lens and/or microlens parallax). When combined with the measured crossing time, these effects can yield planet/host masses and distance.

• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.142-148
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• 2002

Although ionizing radiation (IR) has been used to treat the various human cancers, IR is cytotoxic not only to cancer cells but to the adjacent normal tissue. Since normal tissue complications are the limiting factor of cancer radiotherapy, one of the major concerns of IR therapy is to maximize the cancer cell killing and to minimize the toxic side effects on the adjacent normal tissue. As an attempt to develop a method to monitor the degree of radiation exposure to normal tissues during radiotherapy, we investigated the transcriptional responses of human peripheral blood lymphocytes (PBL) following IR using cDNA microarray chip containing 1,221 (1.2 K) known genes. Since conventional radiotherapy is delivered at about 24 h intervals at 180 to 300 cGy/day, we analyzed the transcriptional responses ex-vivo irradiated human PBL at 200 cGy for 24 h-period. We observed and report on 1) a group of genes transiently induced early after IR at 2 h, 2) of genes induced after IR at 6 h, 3) of genes induced after IR at 24 h and on 4) a group of genes whose expression patters were not changed after IR. Since Biological consequences of IR involve generation of various reactive oxygen species (ROS) and thus oxidative stress induced by the ROS is known to damage normal tissues during radiotherapy, we further tested the temporal expression profiles of genes involved in ROS modulation by RT-PCR. Specific changes of 6 antioxidant genes were identified in irradiated PBL among 9 genes tested. Our results suggest the potential of monitoring post-radiotherapy changes in temporal expression profiles of a specific set of genes as a measure of radiation effects on normal tissues. This type of approach should yield more useful information when validated in in vivo irradiated PBL from the cancer patients.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.667-677
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• 2020

Crop water stress can be detected based on soil moisture content, crop physiological characteristics and remote-sensing technology. The detection of crop water stress is an important issue for the accurate assessment of yield decline. The crop water stress index (CWSI) has been introduced based on the difference between leaf and air temperature. In this paper, drone-based thermal infrared image was used to map of crop water stress in water control plot (WCP) and water deficit plot (WDP) over spring chinese cabbage fields. The spatial distribution map of CWSI was in strong agreement with the abnormal growth response factors (plant height, plant diameter, and measured value by chlorophyll meter). From these results, CWSI can be used as a good method for evaluation of crop abnormal growth monitoring.

• Journal of Biosystems Engineering
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• v.43 no.2
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• pp.148-159
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• 2018

Purpose: Unmanned air vehicle (UAV) remote sensing was applied to test various vegetation indices and make prediction models of protein content of rice for monitoring grain quality and proper management practice. Methods: Image acquisition was carried out by using NIR (Green, Red, NIR), RGB and RE (Blue, Green, Red-edge) camera mounted on UAV. Sampling was done synchronously at the geo-referenced points and GPS locations were recorded. Paddy samples were air-dried to 15% moisture content, and then dehulled and milled to 92% milling yield and measured the protein content by near-infrared spectroscopy. Results: Artificial neural network showed the better performance with $R^2$ (coefficient of determination) of 0.740, NSE (Nash-Sutcliffe model efficiency coefficient) of 0.733 and RMSE (root mean square error) of 0.187% considering all 54 samples than the models developed by PR (polynomial regression), SLR (simple linear regression), and PLSR (partial least square regression). PLSR calibration models showed almost similar result with PR as 0.663 ($R^2$) and 0.169% (RMSE) for cloud-free samples and 0.491 ($R^2$) and 0.217% (RMSE) for cloud-shadowed samples. However, the validation models performed poorly. This study revealed that there is a highly significant correlation between NDVI (normalized difference vegetation index) and protein content in rice. For the cloud-free samples, the SLR models showed $R^2=0.553$ and RMSE = 0.210%, and for cloud-shadowed samples showed 0.479 as $R^2$ and 0.225% as RMSE respectively. Conclusion: There is a significant correlation between spectral bands and grain protein content. Artificial neural networks have the strong advantages to fit the nonlinear problem when a sigmoid activation function is used in the hidden layer. Quantitatively, the neural network model obtained a higher precision result with a mean absolute relative error (MARE) of 2.18% and root mean square error (RMSE) of 0.187%.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.76-85
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• 2004

Anaerobic decomposition of municipal solid waste (MSW) had potential adverse impacts such as the production of methane and long-term post closure on human health and the environment. It was demonstrated that aerobic degradation of MSW resulted in the reduction of a methane yield and the enhancement of stabilization of MSW. Excavated solid wastes were both aerobically and anaerobically treated in order to evaluate the effects of air injection on the stabilization of landfill site. The municipal solid waste (MSW) samples were excavated from a 10-year old landfill (operation period: 1991. 11~1994. 11), Jeonju, Korea. Excavated municipal solid wastes are primarily composed of soils and vinyl/plastics. For the two aerobic simulated lysimeters, the levels of $O_2$ ranged 1.6~23.1% and the levels of $CO_2$ ranged 1.5~15.1%, which confirmed the aerobic decomposition. Aeration did prevent methane formation. For the anaerobic simulated lysimeter, the $CO_2$ rose as $O_2$ was consumed and low levels of CH4 were produced. The pH levels ranged from 7.7 to 8.9 for anaerobic lysimeter and from 7.3 to 8.5 for aerobic lysimeters. As expected, aerobic treatment proved to enhance the removal of biodegradable materials in the excavated solid wastes when monitoring the concentration of BOD, COD, $NH_4-N$, and $NO_3-N$ in the leachate.