• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.188-195
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• 2021

This study was conducted to investigate the growth and quality characteristics of melon (Cucumis melo L.) cultivars and the irrigation requirements for cultivars. In our previous study in 2019, twelve melon cultivars including 'Dalgona' were examined for their cultivar characteristics under the same irrigation condition for all cultivars, and sorted into several groups based on different growth condition; for the internode length (from 0 to 20th node), leaf area, and fruit weight, 'Kingstar' belonged to the largest group, 'Worldstar' the middle group, and 'Dalgona' the smallest group. After analyzing the results of the previous experiment, 'Dalgona', 'Worldstar', 'Kingstar', and 'Rubyball' were selected as test cultivars for the growth group in 2020, and irrigated according to different irrigation levels for each cultivar. The control of the irrigation volume for each melon cultivar by monitoring the drainage rate during the cultivation periods showed that all four cultivars required a similar amount of irrigation in the 'early growth' stage where crops grew at about the same rate. From 'flowering time', however, the change in irrigation requirements showed a similar tendency for 'Worldstar' and 'Kingstar' and for 'Rubyball' and 'Dalgona' respectively. A sudden change in each irrigation volume was observed from the fruit set; 'Dalgona' began first to decline and 'Rubyball' was second, followed by 'Worldstar' and 'Kingstar'. In conclusion, the irrigation volume was the largest in 'Kingstar', followed by 'Worldstar', 'Rubyball', and 'Dalgona' in the same order as the growing amount of plant length, leaf area, and fruit weight. Therefore, it is necessary to control exactly the irrigation volume by reflecting the unique growth characteristics of each cultivar for the production of high-quality fruit in melon hydroponics, and especially to use great care when different cultivars are cultivated together.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.163-167
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• 2009

Jogwang is a new early maturing japonica rice developed in 2007 from a cross between Milyang187 and YR21113-B-B at the Department of Functional Crop Science, NICS, RDA. This cultivar is very suitable to the rice-cash crop double cropping system. Heading date of Jogwang is 2 days earlier than Keumobyeo under the late transplanting cultivation on July 10 at the Yeongnam plain. The tolerance level of this variety to leaf discoloration at seedling stage is very similar to Keumobyeo. It showed slightly lower viviparous germination and premature heading. This cultivar showed resistant reactions to leaf blast and rice stripe virus disease but susceptible to bacterial blight disease and major insect pests. The ratio of milling and head rice recovery of Jogwang is 76.5% and 64.5%, respectively. The milled kernels are translucent with non glutinous endosperm. This cultivar has 7.3% protein and 18.5% amylose content. In local adaptability test, showed that the milled rice yield of Jogwang is $4.90\;MT\;ha^{-1}$. This cultivar is suitable for planting in the plain paddy fields of Honam and Yeonnam regions in Korea.

• The Korean Journal of Archival Studies
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• no.10
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• pp.276-322
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• 2004

Historical interest in China in 1930s has been mostly focused on political characteristic of the National Government(國民政府) which was established by the KMT(中國國民黨) as a result of national unification. It is certain that China had a chance to construct a modern country by the establishment of the very unified revolutionary government. But, it was the time of expanding national crises that threatened the existence of the country such as the Manchurian Incident and the Chinese-Japanese War as well as the chaos of the domestic situation, too. So it has a good reason to examine the characteristic and pattern of the response of the political powers of those days. But, as shown in the recent studies, the manifestation method of political power by the revolutionary regime catches our attention through the understanding of internal operating system. Though this writing started from the fact that the Nationalist Government executed the administrative reform which aimed at "administrative efficiency" in the middle of 1930s, but it put stress on the seriousness of the problem and its solution rather than political background or results. "Committee on Administrative Efficiency(行政效率委員會)", the center of administrative reform movement which was established in 1934, examined the plan to execute the reform through legislation by the Executive Council(行政院) on the basis of the results of relevant studies. They claimed that the construction of a modern country should be performed by not political revolution anymore but by gradual improvement and daily reform, and that the operation of the government should become modern, scientific and efficient. There were many fields of administrative reform subjects, but especially, the field of records and archives adminstration(文書檔案行政) was studied intensively from the initial stage because that subject had already been discussed intensively. They recognized that records and archives were the basic tool of work performance and general activity but an inefficient field in spite of many input staff members, and most of all, archival reform bring about less conflicts than the fields of finance, organization and personnel. When it comes to the field of records adminstration, the key subjects that records should be written simply, the process of record treatment should be clear and the delay of that should be prevented were already presented in a records administrative meeting in 1922. That is, the unified law about record management was not established, so each government organization followed a conventional custom or performed independent improvement. It was through the other records administrative workshop of the Nationalist Government in 1933 when the new trend was appeared as the unified system improvement. They decided to unify the format of official records, to use marker and section, to unify the registration of receipt records and dispatch records and to strengthen the examination of records treatment. But, the method of records treatment was not unified yet, so the key point of records administrative reform was to establish a unified and standard record management system for preventing repetition by simplifying the treatment procedure and for intensive treatment by exclusive organizations. From the foundation of the Republic of China to 1930s, there was not big change in the field of archives administration, and archives management methods were prescribed differently even in the same section as well as same department. Therefore, the point at issue was to centralize scattered management systems that were performed in each section, to establish unified standard about filing and retention period allowance and to improve searching system through classification and proper number allowance. Especially, the problem was that each number system and classification system bring about different result due to dual operation of record registration and archives registration, and that strict management through mutual contrast, searching and application are impossible. Besides, various problems such as filing tools, arrangement method, preservation facilities & equipment, lending service and use method were raised also. In the process this study for the system improvement of records and archives management, they recognized that records and archives are the identical thing and reached to create a successive management method of records and archives called "Records and Archives Chain Management Method(文書檔案連鎖法)" as a potential alternative. Several principles that records and archives management should be performed unitedly in each organization by the general record recipient section and the general archives section under the principle of task centralization, a consistent classification system should be used by classification method decided in advance according to organizational constitution and work functions and an identical number system should be used in the process of record management stage and archive management stage by using a card-type register were established. Though, this "Records and Archives Chain Management Method" was developed to the stage of test application in several organizations, but it was not adopted as a regular system and discontinued. That was because the administrative reform of the Nationalist Government was discontinued by the outbreak of the Chinese-Japanese War. Even though the administrative reform in the middle of 1930s didn't produce practical results but merely an experimentation, it was verified that the reform against tradition and custom conducted by the Nationalist Government that aimed for the construction of a modern country was not only a field of politics, but on the other hand, the weak basis of the government operation became the obstacle to the realization of the political power of the revolutionary regime. Though the subject of records and archives administrative reform was postponed to the future, it should be understood that the consciousness of modern records and archives administration and overall studies began through this examination of administrative reform.

• Clean Technology
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• v.25 no.1
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• pp.91-97
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• 2019

Oxidative desulfurization (ODS) has received much attention in recent years because refractory sulfur compounds such as dibenzothiophenes can be oxidized selectively to their corresponding sulfoxides and sulfones, and these products can be removed by extraction and adsorption. In this work, The oxidative desulfurization of marine diesel fuel was performed in a batch reactor with hydrogen peroxide ($H_2O_2$) in the presence of various supported heteropoly acid catalysts. The catalysts were characterized by XRD, XRF, XPS and nitrogen adsorption isotherm techniques. Based on the sulfur removal efficiency of promising silica supported heteropoly acid catalysts, the ranking of catalytic activity was: $30\;H_3PW_{12}/SiO_2$ > $30\;H_3PMo_{12}/SiO_2$ > $30\;H_4SiW_{12}/SiO_2$, which appears to be related with their intrinsic acid strength. The $30\;H_3PW_{12}/SiO_2$ catalyst showed the highest initial sulfur removal efficiency of about 66% under reaction conditions of $30^{\circ}C$, $0.025g\;mL^{-1}$ (cat./oil), 1 h reaction time. However, through the recycle test of the $H_3PW_{12}/SiO_2$ catalyst, significant deactivation was observed, which was attributed to the elution of the active component $H_3PW_{12}$. By introducing cesium cation ($Cs^+$) into the $H_3PW_{12}/SiO_2$ catalyst, the stability of the catalyst was improved with changing the solubility, and the $Cs^+$ ion exchanged catalyst could be recycled for at least five times without severe elution.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.19-30
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• 2019

Objective of this study was to develop an organic fertilizer utilizing domestic livestock horn meal and to investigate the application effect of rice and eggplant. The possibility of utilization of livestock horn meal as an organic resource to replace imported expeller cake fertilizer was examined. In order to select domestic organic resources with high nitrogen content, 8 kinds of organic matter such as chicken manure, fish meal, soybean meal, sesame meal, perilla meal, blood meal, livestock horn meal, and beer sludge were analyzed and organic resources with high nitrogen content were selected. In addition, the conditions for the production of organic fertilizers that can be used in organic agriculture were established by mixing of the rice husk biochar and the rice bran as the supplements with the raw materials for mixing ratios. The content of total nitrogen (T-N) in the livestock horn meal was 12.0 %, which was the next low in 13.5 % blood meal. The content of total nitrogen was 5.9 ~ 7.9 % in fish meal and oil cakes. Total nitrogen content of non-antibiotic chicken manure for organic farming was 3 % and nitrogen content in beer sludge was 3.5 %. Organic fertilizer was produced by using biochar, rice bran as a main ingredient of non-antibiotic chicken manure, livestock horn meal and beer sludge. Compared to nitrogen content (4.0 to 4.2 %) of imported expeller cake fertilizer (ECF), the nitrogen content of organic fertilizer utilizing domestic livestock horn meal is as high as 7.5 %. The developed organic fertilizer is met as Zn 400 mg/kg, Cu 120 mg/kg the quality of organic agricultural materials such as or less. To investigate the effect of fertilizer application on the crops, prototypes of developed organic fertilizer were used for the experiment under selected conditions. As a result of application the developed organic livestock horn meal fertilizer (LHMF) for cultivation of the rice and eggplant, the application quantity of the developed organic LHMF 100 % was decreased by 40 % compared to that of the mixed expeller cake fertilizer (MECF). The application of LHMF, which refers to the application rate corresponding to the nitrogen fertilization recommended by the soil test, was reduced by 40% compared to the application rate of MECF, but the same results were obtained in crop growth and yield. The selection of a new high concentration nitrogen source utilizing domestic organic resources and the development of organic fertilizer is the starting point of the research for substitution of imported ECF using domestic local resources at the present time that the spread of eco-friendly agriculture is becoming increasingly important. If it is expanded in the future, it is expected to contribute to the stable production of eco-friendly agricultural products.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.127-137
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• 2021

Air emission charge for nitrogen oxide as a precursor of fine dust has been introduced and implemented within the country from 2020. Therefore, the development of economical combustion technology for NOx reduction has got more needed urgently. This study investigated the air-staging effect as a way to reduce the NOx during combustion of domestic unused forest biomass, recently possible to secure REC (Renewable Energy Certification) as a substitute for overseas wood pellets in a 0.1 MWth circulating fluidized bed combustion test-rig. Operating conditions were comparison with and without air-staging, the supply position of tertiary air (6.4 m, 8.1 m, 9.4 m in the combustor) and variation of air-staging ratio (Primary air:Secondary air:Tertiary air=91%:9%:0%, 82%:9%:9%, 73%:9%:18%). NO and CO concentrations in flue gas, profiles of temperature and pressure at the height of the combustion, unburned carbon in sampled fly ash and combustion efficiency on operating conditions were evaluated. As notable results, NO concentration with air-staging application under tertiary air supply at 9.4 m in the combustor reduced 100.7 ppm compared to 148.8 ppm without air-staging while, CO concentration increased from 52.2 ppm without air-staging to 99.8 ppm with air-staging. However, among air-staging runs, when tertiary air supply amount at 6.4 m in the combustor increased by air-staging ratio (Primary air:Secondary air:Tertiary air=73%:9%:18%), NO and CO concentrations decreased the lowest 90.8 ppm and 66.1 ppm, respectively. Furthermore, combustion efficiency at this condition was improved to 99.3%, higher than that (98.3%) of run without air-staging.

• Economic and Environmental Geology
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• v.55 no.2
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• pp.209-217
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• 2022

The purpose of this study was to confirm the dissolution of arsenic from the stabilized soil around abandoned coal mines by cultivation activities. Experimental soils were collected from the agricultural field around Okdong and Buguk coal mines, and the concentration of arsenic in the soil and the geochemical mobility were confirmed. The average arsenic concentration was 20 mg/kg. The soil with relatively high geochemical mobility of arsenic in the soil was used in the batch and column experiment. The limestone was mixed with soil for soil stabilization, and the mixing ratio was 3% of limestone, based on the soil weight. The phosphoric acid fertilizer (NH₄H₂PO₄) was added to the soil to simulate a cultivation condition according to the Rural Development Administration's rules. Comparative soil without mixing limestone was prepared and used as a control group. The arsenic extraction from soil was increased following the fertilizer mixing amount and it shows a positive relationship. The concentration of phosphate in the supernatant was relatively low under the condition of mixing limestone, which is determined to be result of binding precipitation of phosphate ions and calcium ions dissolved in limestone. Columns were set to mix phosphoric acid fertilizers and limestone corresponding to cultivation and stabilization conditions, and then the column test was conducted. The variations of arsenic extraction from the soil indicated that the stabilization was effectible until 10 P.V.; however, the stabilization effect of limestone decreased with time. Moreover, the geochemical mobility of arsenic has transformed by increasing the mobile fractions in soil compared to initial soil. Therefore, based on the arsenic extraction results, the cultivation activities using phosphoric fertilizer could induce a decrease in the stabilization effect.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.451-468
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• 2021

Predicting hazardous ground conditions ahead of a TBM (Tunnel Boring Machine) tunnel face is essential for efficient and stable TBM advance. Although there have been several studies on the electrical resistivity survey method for TBM tunnelling, sufficient experimental data considering TBM advance were not established yet. Therefore, in this study, the laboratory-scale model experiments for simulating TBM excavation were carried out to analyze the applicability of an electrical resistivity survey for predicting hazardous ground conditions ahead of a TBM tunnel face. The trend of electrical resistivity during TBM advance was experimentally evaluated under various hazardous ground conditions (fault zone, seawater intruded zone, soil to rock transition zone, and rock to soil transition zone) ahead of a tunnel face. In the course of the experiments, a scale-down rock ground was provided using granite blocks to simulate the rock TBM tunnelling. Based on the experimental data, the electrical resistivity tends to decrease as the tunnel approaches the fault zone. While the seawater intruded zone follows a similar trend with the fault zone, the resistivity value of the seawater intrude zone decreased significantly compared to that of the fault zone. In case of the soil-to-rock transition zone, the electrical resistivity increases as the TBM approaches the rock with relatively high electrical resistivity. Conversely, in case of the rock-to-soil transition zone, the opposite trend was observed. That is, electrical resistivity decreases as the tunnel face approaches the rock with relatively low electrical resistivity. The experiment results represent that hazardous ground conditions (fault zone, seawater intruded zone, soil-to-rock transition zone, rock-to-soil transition zone) can be efficiently predicted by utilizing an electrical resistivity survey during TBM tunnelling.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.548-556
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• 2022

Acylases can have a significant effect on biofilm formation owing to their quorum quenching activity. In this study, we investigated the effects of acylase treatment episodes on multispecies biofilm development. A consortium composed of 9 species belonging to different genera was allowed to form biofilms for 5 days under various treatment episodes (different treatment periods, 1, 2, 3, or 4 days; and two application timings, beginning or later) at 1, 5, 10, 20 and 50 mg·l^-1 acylase concentrations. The acylase treatment for 5 days showed that acylase concentration was negative with biofilm development (linear regression, Y = -0.05·x + 2.37, p < 0.05, R² = 0.88). Acylase was more effective in reducing biofilm formation when it was applied in the beginning (vs. in later development stage) at all acylase concentrations (p < 0.05). ANOVA indicated that treatment period was significant on biofilm formation in both application timings at ≥ 10 mg·l^-1 (p < 0.05). Linearity test results showed that all slope values between period and biofilm were negative in both timings at ≥ 10 mg·l^-1 (p < 0.05, except for the later application at 20 mg·l^-1). When temporal biofilm dynamics were monitored at 20 mg·l^-1, biofilms gradually increased with time at all treatment episodes (p < 0.05), and slope values in linear regression between biofilm and time were lower when acylase was applied in the beginning (p < 0.05). Our findings suggest the importance of the acylase treatment period and application timing on biofilm control.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.