• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.81-85
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• 1989

One of the most important cultural techniques of pearl millet (Pennisetum americanum (L.) Leeke) is to encourage rapid and uniform emergence of seedlings to establish good stand and to let them grow well. Thus the objectives of the study were to investigate the effects of pre-sowing seed soaking and planting depth on dormancy breaking, germination and emergence of the seedlings, and to estimate the optimum planting season of pearl millet in Suwon, Korea. The seeds with dormancy germinated 99 to 100 percent when soaked in the H$_2$O$_2$ 1％ solution for 24 hours and rinsed with pure water, but germinated only 38％ and 83％ when soaked in pure water for 24 hours just after harvest and drying, and one month later from the harvest time, respectively. The seeds of Australia inbred line did not germinate at the constant 10$^{\circ}C$, but germinated at the constant 11$^{\circ}C$. It also was possible to estimate the optimum planting season by applying minimum temperature 11$^{\circ}C$ for germination. The minimum air temperature reached from late April in Suwon, Korea in regular years but fluctuated from late April to early May in 1986 and 1987. Thus, the safe planting season was mid-May for rapid and uniform germination of pearl millet seed. The optimum depth of planting was 2∼4cm under the optimum soil moisture condition, and 4 to 6 cm under the drier soil moisture condition. Subcoleoptile internode(mesocotyle) length increased according to increased depth of planting. Seedling crown placement also became deeper due to deeper planting of the seeds. The subcoleoptile internode length and seedling crown depth were positively correlated with actual planting depth, indicating that deeper planting would be not good for appropriate adventitious root and tiller development.

• Clean Technology
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• v.23 no.2
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• pp.196-204
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• 2017

CdZnS/ZnO composite was prepared through low-temperature precipitation and drying method. The property of CdZnS/ZnO as a recyclable photocatalyst for the degradation of rhodamine B (RhB) under visible light irradiation was examined. The sample was characterized by XRD, FE-SEM, XPS, UV-vis DRS and photoluminescence techniques before and after repeated reaction to investigate the change of properties during the photocatalytic reaction. During repeated reaction, the CdZnS/ZnO showed an improved photocatalytic activity and recycle stability. Among two feasible reaction pathways for photocatalytic degradation of RhB, the cleavage of conjugated chromophore was found to predominate over N-dealkylation of chromophore skeleton in the present work. The results indicate that the CdZnS/ZnO, prepared by a simple precipitation method, can be used as a visible-light driven photocatalyst with enhanced cycle stability and activity.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.87-98
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• 1994

Sludge minimization in an water treatment plant can be achieved by optimizing a main water treatment process as well as by enhancing a thickening and a dewatering facilities. In this study, dewatering and drying techniques for reducing the quantity of the water sludge generated from the conventional water treatment plant in the local states were investigated by reducing its water content. Not only the types and dosages of polymers but also the mixing intensity of the mixtures of a concentrated sludge and polymers on the different pH were evaluated for the optimum dewatering conditions of the water sludge. Weight reduction of the water sludge was also tested at a given temperature range. The dewatering efficiency of the water sludge was not affected by the types of polymer but by mixing intensity(GT value) in this study. pH effect on dewaterbility of the water sludge took a major role at the neutral pH range. The optimal polymer dose was 1.5 mg-polymer/g-TSS(about 40mg/L as polymer). Dewaterability was enhanced at a lower mixing intensity(GTbelow 10,000 sec-1). Free water in the void of sludge cake was dried around $100^{\circ}C$, chemical bound water was evaporated around $320^{\circ}C$, and organic material was burned out at the range of 300 to $600^{\circ}C$. Ignition losses of the water sludge were varied 15 to 40 % as the raw water quality. The ignition loss due to the chemical bound water was 10-20% and the loss due to the organic material was 4-20% of the total ignition loss.

• Journal of Conservation Science
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• v.31 no.2
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• pp.125-130
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• 2015

Specific techniques and materials in conservation of traditional lacquer has not been transmitted. This study aims to compare the basic characteristics of the filler which used in the base layer of lacquer conservation. Tohoe(a mixture of lacquer and Clay) and the three kinds of additives which is mixed with Tohoe and Goksu(a mixture of lacquer, wood powder and rice starch) are estimated in drying rate, impact resistance, abrasion. Among those samples, the more amount of clay causes fast dryness speed and worse cracks on the surface. The impact resistance is weakened at high amount of clay. There is no significant differences of impact resistance between both additives that is mixed with the samples and additives. The samples that are mixed with Goksu and additives show high impact resistance. In the polishing test, the more amount of filling powders show higher grinding degree and the sample that are mixed with wood powder and charcoal show higher degree as well. The highest grinding degree is Maekchil and Goksu but the lowest one is the sample of the rooftile powder mixture.

• 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.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.2
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• pp.193-201
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• 2021

The welding has a high proportion of the production and drying of ships or offshore plants. Non-destructive testing is carried out to verify the quality of welds in Korea, radiography test (RT) is mainly used. Currently, most shipyards adopt analog-type techniques to print the films through the shoot of welding parts. Therefore, the time required from radiography test to pass or fail judgment is long and complex, and is being manually carried out by qualified inspectors. To improve this problem, this paper covers a platform for scanning and digitalizing RT films occurring in shipyards with high resolution, accumulating them in management servers, and applying artificial intelligence (AI) technology to detect welding defects. To do this, we describe the process of designing and developing RT film scanning equipment, welding inspection information integrated management platform, fault reading algorithms, visualization software, and testing and verification of each developed element in conjunction.

• Journal of Conservation Science
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• v.37 no.6
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• pp.701-711
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• 2021

This study identifies the structure and material characteristics of the mural paintings in Daeungjeon at Ssanggyesa temple in Jindo by conducting scientific research and analysis including microscope examination, SEM-EDS, XRD, particle size analysis, and others. According to the analyses, the murals were considered to be of a typical soil mural style for Korean Buddhist murals, given that the walls were made of sand and soil and the murals had layers consisting of wall layers and a finishing layer. However, some finishing layer used calcite, while some ground layer used zinc white beneath the thick paint. In addition, there were similar features to those found on the surfaces of oil paintings such as cracks along with the paint layer, high gloss on surfaces, and thick brush strokes in many areas. It was found that the walls on which the murals were painted were made of soil but that the paint layer was created based on the oil painting technique using drying oil. It determined that the murals were painted in a unique painting style that is rarely found in other typical Buddhist murals in Korea.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.14-22
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• 2016

A trial of combining and quantifying the effects of food processing on various pesticides was carried out using a meta-analysis. In this study, weighted mean response ratios and confidence intervals about the reduction of pesticide residue levels in fruits and vegetables treated with various food processing techniques were calculated using a statistical tool of meta-analysis. The weighted mean response ratios for tap water washing, peeling, blanching (boiling) and oven drying were 0.52, 0.14, 0.34 and 0.46, respectively. Among the food processing methods, peeling showed the greatest effect on the reduction of pesticide residues. Pearsons's correlation coefficient (r=0.624) between weighted mean response ratios and octanolwater partition coefficients ($logP_{ow}$) for twelve pesticides processed with tap water washing was confirmed as having a positive correlation in the range of significance level of 0.05 (p=0.03). This means that a pesticide having the higher value of $logP_{ow}$ was observed as showing a higher weighted mean response ratio. These results could be used effectively as a reference data for processing factor in risk assessment and as an information for consumers on how to reduce pesticide residues in agricultural products.