• Korean Journal of Soil Science and Fertilizer
• /
• v.35 no.4
• /
• pp.216-222
• /
• 2002

Field experiments were conducted to investigate the effect of various cultural practices on methane($CH_4$) emission in tillage and no-tillage practice in a clayey paddy soil from 1998 to 2000. The factors evaluated in tillage and no-tillage methods were types of nitrogen fertilizers, application method of chemical fertilizers, rice straw application and cultivation method. Of the nitrogen fertilizers, the amount of $CH_4$ emission in ammonium sulfate plot was the lowest, regardless of tillage and the application method. 26.4~41.1% of reduction by ammonium sulfate compared with urea. But in no-tillage which have problem of poor rice yield than tillage, coated urea was more effective nitrogen fertilizer because that showed similar $CH_4$ emission and highest rice yield at 80% of dosage of nitrogen. No-tillage plot emitted lower $CH_4$ than tillage plot where the fertilizers were incorporated. On the contrary, no-tillage plot showed a little higher $CH_4$ emission compared with tillage plot for the surface application. When rice straw was applied, no-tillage practice reduced methane emission by 26.6% compared with tillage practice, but showing a little difference of 10.7% in no application. With cultivation method, no-tillage practice reduced methane emission 26.6% compared with tillage for the 30-d-old seedling transplanting. But for the dry direct seeding practice, no-tillage was a less effective because considerable amounts of rice straw incorporated by tillage were more decomposed aerobically in the soil and emitted as $CO_2$ to the atmosphere with flooding in no-tillage soil.

• Journal of Animal Environmental Science
• /
• v.18 no.2
• /
• pp.123-130
• /
• 2012

This study was conducted to investigate the effects of cattle slurry on productivity of whole crop barley and Italian ryegrass and environmental pollution in paddy land. Cropping systems used in this study were consisted of two designs, such as whole crop barley applied with cattle slurry (WCB) and Italian ryegrass applied with cattle slurry (IRG). The field experiments were conducted on the clay loam at Backsanmyun, Kimje, Chunlabukdo province in Korea for three years (May 2006 to Apr. 2009). This study was arranged in completely randomized design with three replicates. The yields of WCB and IRG were 7,520 kg/ha and 10,320 kg/ha, respectively. The yields of IRG significantly increased as compared with that of WCB (p<0.05). The yield of Italian ryegrass in 1st cutting time was about 2-fold higher than that of 2nd cutting time. The contents of crude protein of IRG were higher than that of WCB. However, the contents of NDF, ADF and TDN were no difference between WCB and IRG treatments. The pH, and contents of T-N, $P_2O_5$ and organic matter (OM) in soil samples collected at the end of the experiment increased as compared with those at the beginning of the experiment (p<0.05). After the end of experiment, the concentrations of CEC (Ca, Na, Mg and K) in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (p<0.05). The concentrations of $NH_4$-N, $NO_3$-N, $PO_4$-P, Cl, Ca, K, Mg and Na in leaching water in paddy land cultivated with WCB and IRG were no difference between WCB and IRG treatments.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.5 no.3
• /
• pp.180-186
• /
• 1985

Field and phytotron experiments were conducted to determine the effect of morphological growth stage and environmental temperature on Weender components and net energy lactation (NEL) in corn cv. Blizzard and sorghum cv. Pioneer 931 and Sioux at Munich Technical University from 1978 to 1981. Various growth stages of maize and sorghum were grown for 42 days at 4 temperature regimes (30/25, 25/20, 28/18 and 18/8 degree C) and mid-summer sunlight over 13 hour days. The results obtained are summarized as follows: 1. Accumulation of crude protein in maize and sorghum plants was associated with leaf weight ratio and leaf area ratio ($P{\leq}0.1%$). Crude protein in the plants were shown to have a greate synthesis rates at early growth stages. The highest concentration of crude protein were found at 3-leaf stage with 31.4% and 33.9% for maize and sorghum, respectively. 2. Synthesis of crude fiber was increased after growing point differentiation markedly and were shown the highest concentration at heading stage with 28.4% and 31.5% for maize and sorghum, respectively. During the maturities, the crude fiber contents in maize were, however decreased and shown a value of 19.5% at physiological maturity, while that of sorghum were increased continuously. 3. NEL value in maize and sorghum plants were declined as morphological development and shown the lowest at growing point differentiation with 5.82 MJ (maize) and 5.46 MJ/kg (sorghum). During the late maturity, the NEL value of maize were increased markedly and shown a value of 6.70 MJ and 6.94 MJ/kg for milkstage and maturity stage, respectively, while NEL value in sorghum were not increased markedly. 4. Net energy lactation in maize and sorghum plants were associated with synthesis rate of non-structural carbohydrates, especially mono- and disaccharose while cell-wall constituents and crude fiber lowerd NEL contents ($P{\leq}0.1%$). 5. NEL accumulation and starch value were decreased under temperature. The NEL concentration of 4-leaf sorghum under different environmental temperatures of 30/25, 25/20, and 18/8 degree C were 4.87 MJ, 5.46 MJ and 5.81 MJ/kg, respectively.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.1
• /
• pp.45-52
• /
• 1989

The effects of soil properties and N, P and K application rates on the contents of inorganic constituents in the rhizomas of Ji-whang were investigated to know the condition for producing the better quality rhizoma of Ji-whang. Most of soil texture for Ji-whang cultivating belongs to sandy clay loam and sandy loam soils. The nitrogen contents in the rhizomas of Ji-whang was negatively correlated with the contents of organic matter and total nitrogen in surface soils, whereas positively correlated with the sand contents in subsoils. The calcium contents in the rhizomas of Ji-whang were negatively correlated with the sand contents, however, positively correlated with the contents of clay and organic matter in soils. The iron contents was positively correlated with the contents of clay, available phosphorus and exchangeable potassium in surface soils. Much more contents of the inorganic constituents in the leaf of Ji-whang was generally detected than that in the rhizoma of Ji-whang. The contents of iron and copper in the leaf was determined to be more than that in the rhizomas by ten times. In the results of field experiments, it is apparent that the nitrogen contents in the rhizoma and leaf increased with increasing N application rate more than 20kg/10a and 10kg/10a, respectively.

• Journal of Korean Society of Forest Science
• /
• v.108 no.3
• /
• pp.440-453
• /
• 2019

This study was carried out to investigate the effect of watching a two-dimensional (2D) forest video and a virtual reality (VR) forest video on stress reduction in adults. Experiments were conducted in an artificial climate room, and 40 subjects participated. After inducing stress in the subjects, subjects watched a 2D gray video, 2D forest video, or VR forest video for 5 mins. The autonomic nervous system activity was evaluated continuously in terms of measured heart rate variability during the experiment. After each experiment, the subject's psychological state was evaluated using a questionnaire. The 2D forest video decreased the viewer's stress index, increased HF, and reduced heart rate compared with the 2D gray video. The VR forest video had a greater stress index reduction effect, LF/HF increase effect, and heart rate reduction effect than the 2D gray video. Psychological measurements showed that subjects felt more comfortable, natural, and calm when watching the 2D gray video, 2D forest video or VR forest video. We also found that the 2D forest video and VR forest video increased positive emotions and reduced negative emotions compared to the 2D gray video. Based on these results, it can be concluded that watching the 2D forest and VR forest videos reduces the stress index and heart rate compared with watching the 2D gray video. Thus, it is considered that the 2D forest video increases the activity of the parasympathetic nervous system, and the VR forest video increases the activity of the sympathetic nervous system. The increased activity of the sympathetic nervous system upon watching the VR forest video is judged to be positive sympathetic nerve activity, such as novelty and curiosity, and not negative sympathetic activity, such as stress and tension. The results of this study are expected to be the basis for examining the visual effects of forest healing, with hope that the utilization of VR, the technology of the fourth industrial revolution in the forestry field, will broaden.

• Journal of Intelligence and Information Systems
• /
• v.25 no.1
• /
• pp.43-61
• /
• 2019

Development of technologies in artificial intelligence has been rapidly increasing with the Fourth Industrial Revolution, and researches related to AI have been actively conducted in a variety of fields such as autonomous vehicles, natural language processing, and robotics. These researches have been focused on solving cognitive problems such as learning and problem solving related to human intelligence from the 1950s. The field of artificial intelligence has achieved more technological advance than ever, due to recent interest in technology and research on various algorithms. The knowledge-based system is a sub-domain of artificial intelligence, and it aims to enable artificial intelligence agents to make decisions by using machine-readable and processible knowledge constructed from complex and informal human knowledge and rules in various fields. A knowledge base is used to optimize information collection, organization, and retrieval, and recently it is used with statistical artificial intelligence such as machine learning. Recently, the purpose of the knowledge base is to express, publish, and share knowledge on the web by describing and connecting web resources such as pages and data. These knowledge bases are used for intelligent processing in various fields of artificial intelligence such as question answering system of the smart speaker. However, building a useful knowledge base is a time-consuming task and still requires a lot of effort of the experts. In recent years, many kinds of research and technologies of knowledge based artificial intelligence use DBpedia that is one of the biggest knowledge base aiming to extract structured content from the various information of Wikipedia. DBpedia contains various information extracted from Wikipedia such as a title, categories, and links, but the most useful knowledge is from infobox of Wikipedia that presents a summary of some unifying aspect created by users. These knowledge are created by the mapping rule between infobox structures and DBpedia ontology schema defined in DBpedia Extraction Framework. In this way, DBpedia can expect high reliability in terms of accuracy of knowledge by using the method of generating knowledge from semi-structured infobox data created by users. However, since only about 50% of all wiki pages contain infobox in Korean Wikipedia, DBpedia has limitations in term of knowledge scalability. This paper proposes a method to extract knowledge from text documents according to the ontology schema using machine learning. In order to demonstrate the appropriateness of this method, we explain a knowledge extraction model according to the DBpedia ontology schema by learning Wikipedia infoboxes. Our knowledge extraction model consists of three steps, document classification as ontology classes, proper sentence classification to extract triples, and value selection and transformation into RDF triple structure. The structure of Wikipedia infobox are defined as infobox templates that provide standardized information across related articles, and DBpedia ontology schema can be mapped these infobox templates. Based on these mapping relations, we classify the input document according to infobox categories which means ontology classes. After determining the classification of the input document, we classify the appropriate sentence according to attributes belonging to the classification. Finally, we extract knowledge from sentences that are classified as appropriate, and we convert knowledge into a form of triples. In order to train models, we generated training data set from Wikipedia dump using a method to add BIO tags to sentences, so we trained about 200 classes and about 2,500 relations for extracting knowledge. Furthermore, we evaluated comparative experiments of CRF and Bi-LSTM-CRF for the knowledge extraction process. Through this proposed process, it is possible to utilize structured knowledge by extracting knowledge according to the ontology schema from text documents. In addition, this methodology can significantly reduce the effort of the experts to construct instances according to the ontology schema.

• Economic and Environmental Geology
• /
• v.54 no.6
• /
• pp.689-698
• /
• 2021

Since the mine reclamation scheme was implemented from 2007 in Korea, various remediation programs have been decontaminated the pollution associated with mining and 254 mines were managed to reclamation from 2011 to 2015. However, as the total amount of contaminated mine drainage has been increased due to the discovery of potential hazards and contaminated zone, more efficient and economical treatment technology is required. Therefore, in this study, the adsorption properties of arsenic was evaluated according to the adsorbents which were derived from water treatment sludge(Alum based adsorbent, ABA-500) and granular ferric hydroxide(GFH), already commercialized. The alum sludge and GFH adsorbents consisted of aluminum, silica materials and amorphous iron hydroxide, respectively. The point of zero charge of ABA-500 and GFH were 5.27 and 6.72, respectively. The result of the analysis of BET revealed that the specific surface area of GFH(257 m²·g^-1) was larger than ABA-500(126~136 m²·g^-1) and all the adsorbents were mesoporous materials inferred from N₂ adsorption-desorption isotherm. The adsorption capacity of adsorbents was compared with the batch experiments that were performed at different reaction times, pH, temperature and initial concentrations of arsenic. As a result of kinetic study, it was confirmed that arsenic was adsorbed rapidly in the order of GFH, ABA-500(granule) and ABA-500(3mm). The adsorption kinetics were fitted to the pseudo-second-order kinetic model for all three adsorbents. The amount of adsorbed arsenic was increased with low pH and high temperature regardless of adsorbents. When the adsorbents reacted at different initial concentrations of arsenic in an hour, ABA-500(granule) and GFH could remove the arsenic below the standard of drinking water if the concentration was below 0.2 mg·g^-1 and 1 mg·g^-1, respectively. The results suggested that the ABA-500(granule), a low-cost adsorbent, had the potential to field application at low contaminated mine drainage.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.1
• /
• pp.65-77
• /
• 2020

In order to industrialize of Dendranthema indicum (L.) DesMoul., which is a lot of commercially available and is synonymous with chrysanthemum tea, in the autumn of 2018, Dendranthema indicum (L.) DesMoul. seeds were collected from its own native region, and the seeds were germinated after refrigerated storage. Young seedlings were subjected to experiments in February, March, and April in the open field to examine the effects on the harvesting of leaves by distance and the growth of leaves and stems. The results of analyzing the components by collecting the leaves+stem after collecting the flower of Dendranthema indicum (L.) DesMoul. are as follows. 1. When D. indicum (L.) DesMoul. seedlings were planted according to the transplanting date, the number of flowers was 17.1 in the transplanting date in April. The diameter of the flower was 2.9cm, 16ea, 6.5~6.6g in the fresh weight, and the dry weight of the case was 1.1~1.2g. The leaves were 46~47ea in March and April in the planted area, 5.2~5.3cm in leaf length and 3.5~3.6cm in leaf width. 2. When planted D. indicum (L.) DesMoul. seedlings according to transplanting distance, the number of flowers was 16.2 when planted at 20×20cm intervals and, 16.8~17.1 at 30×30~50×50cm intervals. The diameter of the flower was 2.7~2.8cm, the number of petals was 8, the length of the petal was 0.8 cm, and fresh weight was 6.5~6.6g per flower. Leaves had the largest number of 47 of 30×30cm and 40×40cm, and leaf length appeared at the longest 6.2cm in the 50×50cm treatment area, but 5.2cm in the other treatment areas. 3. The extraction yield of D. indicum (L.) DesMoul. leaves+stems was 7.93%, and the extraction solvent colors were light green at 50, 60% and green at 70, 80, 90, 100%. The extraction yield of D. indicum (L.) DesMoul. flowers was 7.58%, the color of the extraction solvent was light yellow at 50, 60 and 70%, yellow at 80 and 90%, and dark yellow at 100%. 4. We confirmed 11 kinds of ingredients such as in D. indicum (L.) DesMoul. flowers are gallic acid, 4-hydroxy benzoic acid, methyl gallate, 4-hydroxy-3-methoxy benzoic, caffeic acid, salicylic acid, p-coumaric acid, sinapic acid, naringin, 4-melthoxyben, flavone. The content was 29.200-36.900ppm. 5. The components contained in the D. indicum (L.) DesMoul. leaf+stem, salicylic acid appeared at 6,129.526ppm, and the next 4-methoxyben was 1,966.714ppm. It was methyl gallate 8.197ppm, 4-hydroxy-3-methoxy benzoic 6.994ppm, caffeic acid 5.566ppm, flavone 4.522ppm, p-coumaric acid 3.787ppm, gallic acid 1.893ppm that appeared in the content below 10ppm.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.2
• /
• pp.123-133
• /
• 2020

Four LEDs (blue, green, red, and white light) were tested to identify the most attractive wave length to utilize as the forecasting tools for the B. tabaci in glass houses. Attractiveness was evaluated by the total number of the B. tabaci attached to a yellow sticky trap. In the condition of no host plant supplement, the attraction efficacy was ordered from high to low as blue light (107.3±2.5), white light (83.0±12.1), red light (58±21.8), and green light (39.7±8.1). In the supplement of the host plant, the attraction was observed in the order of blue light (52±17.4), red light (38.7±5.8), green light (12.7±1.5), and white light (11.7±5.0). In both experimental conditions, blue light showed the highest attraction. In terms of the host plant effect to LED attraction, it varied following as white light (85.9%), green light (68.1%), blue light (51.6%), and red light (33.3%). This result suggests that red light is the least affected by the host plant. In the evaluation of the relative control efficacy, it was determined following as red light (66.7%), blue light (48.5%), green light (31.9%) and white light (14.1%) (F_3,8 = 14.7, P = 0.001). Taken together, blue light had a very high initial attraction, and red light was revealed low attraction effect by the supplement of the host plant. In field demonstration experiments, a high attractive efficacy was not observed due to low-temperature conditions, but similar higher attractive efficacy was observed in blue and red lights compared to the control. The commercialization of LEDs using red and blue in the future is expected to provide important information regarding B. tabaci population density forecast in glass house.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.4
• /
• pp.267-274
• /
• 2022

The effect of year, varieties, nitrogen application, and transplant time were examined in relation to rice of protein. An experiment was conducted using 12 rice varieties to investigate the effect of management and weather conditions on brown rice protein of during the filling stage. The transplanting time was set to be three groups including early, medium, and late timing. The nitrogen application was set to be 0 N kg / 10a, 9N kg / 10a and 18 N kg / 10a to examine the effect of fertilizer management on protein content. Field experiments were conducted in three growing seasons including 2019, 2020, and 2021. The brown rice of protein content were 5.7%, 5.9%, and 6.6% under early, medium, and late transplanting time conditions, respectively. The protein content differ by variety. For example, Chucheong, Hopum, Ilpum, Mipum, Odae, Saenuri, and Saeilmi had more than 6.1%, and Chindeul, Shindongjin, Samkwang, Unkwang, Younhojinmi were less than 6.1%. Nitrogen content was 5.7% for 0kgN /10a, 6.1% for 9kgN /10a, and 6.8% for 18kgN /10a. The contribution of the characteristics to the protein content was highest in nitrogen content (38.8%), followed by transplanting time (13.7%), variety (8.2%), and year (3.5%). The average temperature for 20 days after heading time was the highest (9.3%), followed by sunshine duration (3.9%) and solar radiation (3.5%). Our results revealed that brown rice protein content was determined to be affected by changes in average temperature, sunshine duration and solar radiation for 20 days after heading time. This suggested that assessment of temperature and solar radiation after heading time would indicate the degree of rice quality in terms of protein.