• Clean Technology
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• v.28 no.3
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• pp.218-226
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• 2022

As a result of the recent social transformation towards a hydrogen economy and carbon-neutrality, the demands for hydrogen energy have been increasing rapidly worldwide. As such, eco-friendly hydrogen production technologies that do not produce carbon dioxide (CO₂) emissions are being focused on. Among them, ammonia (NH₃) is an economical hydrogen carrier that can easily produce hydrogen (H₂). In this study, Ru/Al₂O₃ catalyst coated onmetallic monolith for hydrogen production from ammonia was prepared by a dip-coating method using a catalyst slurry mixture composed of Ru/Al₂O₃ catalyst, inorganic binder (alumina sol) and organic binder (methyl cellulose). At the optimized 1:1:0.1 weight ratio of catalyst/inorganic binder/organic binder, the amount of catalyst coated on the metallic monolith after one cycle coating was about 61.6 g L^-1. The uniform thickness (about 42 ㎛) and crystal structure of the catalyst coated on the metallic monolith surface were confirmed through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Also, a numerical optimization regression equation for NH3 conversion according to the independent variables of reaction temperature (400-600 ℃) and gas hourly space velocity (1,000-5,000 h^-1) was calculated by response surface methodology (RSM). This model indicated a determination coefficient (R²) of 0.991 and had statistically significant predictors. This regression model could contribute to the commercial process design of hydrogen production by ammonia decomposition.

• Korean journal of applied entomology
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• v.61 no.2
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• pp.335-347
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• 2022

We investigated the emergence patterns of Chilo suppressalis (Lepidoptera: Crambidae) adults using sex pheromone traps in the three northeastern areas, Dandong (40°07'N 124°23'E) (Liaoning province), and Gongzhuling (43°30'N 124°49') and Longjing (42°46'N 129°26'E) (Jilin province), China, in 2020 and 2021. Two times of adult flight seasons were isolated clearly during the rice growing periods in the all areas, in which the first season from mid May to late July, and the second season from mid July to mid September were observed. The adult emergence seasons in the areas at higher latitude were later than that at lower latitude. Using the adult emergence data during the first flight seasons, the second flight seasons were estimated through insect phenology modelling, and compared with the observed data. Temperature-dependent life history models (developmental rate, development completion, survival rate, adult aging rate, total fecundity, oviposition completion, and adult survival completion) were collected or constructed for each life stage of C. suppressalis, in which the data from the four previous studies were used. Those models were combined in an insect phenology estimation software, PopModel, and operated for the observed areas. In the results, the phenology modelling operated with the models based on the data of shorter larval periods in the previous studies estimated more accurately the second flight seasons. In 2021, we investigated the change of damaged hill ratios of rice with observing the adult emergence at Dandong and Longjing, 2021. The increase periods of damaged hill ratios of rice were observed two times during the total rice cultivation season, which may be caused by different generations of C. suppressalis larvae.

• International Journal of Highway Engineering
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• v.1 no.1
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• pp.107-119
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• 1999

The joints in the jointed concrete pavement provide a control against transverse or longitudinal cracking at slab, which may be caused by temperature or moisture variation during or after hydration. Without control of cracking, random cracks cause more serious distresses and result in structural or functional failure of pavement system. However, joints nay cause distresses due to its inherent weakness in structural integrity. Thus, the evaluation at joint is very important. and the joint-related distresses should be evaluated reasonably for economic rehabilitation. The purpose of this paper was to develop an evaluation system at joints of jointed concrete pavement using finite element analysis program, ILLI-SLAB, and nondestructive testing device. FWD. To develop an evaluation system for JCP, a sensitivity analysis was performed using ILLI-SLAB program with a selected variables which might affect fairly to on the performance of transverse joints. The most significant variables were selected from precise analysis. An evaluation charts were made for jointed concrete pavement by adopting the field FWD data. It was concluded that the variables which most significantly affect to pavement deflections are the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G), and limiting criteria on the performance of joints at JCP are 300pci. 500,000 lb/in. respectively. Using these variables and FWD test, a charts of load transfer ratio versus surface deflection at joints were made in order to evaluate the performance of JCP. Practically, Chungbu highway was evaluated by these evaluation charts and FWD field data for jointed concrete pavement. For Chungbu highway, only one joint showed smaller value than limiting criterion of the modulus of dowel/concrete interaction(G). The rest joints showed larger values than limiting criteria of the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G).

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.69-77
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• 2012

Surface insolation is one of the major indicators for climate research over the Earth system. For the climate research, long-term data and wide range of spatial coverage from the data observed by two or more of satellites of the same orbit are needed. It is important to improve the continuity and consistency of the derived products, such as surface insolation, from different satellites. In this study, surface insolations based on Geostationary Operational Environmental Satellite (GOES-9) and Multi-functional Transport Satellites (MTSAT-1R) were compared during overlap period using physical model of insolation to find ways to improve the consistency and continuity between two satellites through comparison of each channel data and ground observation data. The thermal infrared brightness temperature of two satellites show a relatively good agreement between two satellites : rootmean square error (RMSE)=5.595 Kelvin; Bias=2.065 Kelvin. Whereas, visible channels shown a quite different values, but it distributed similar tendency. And the surface insolations from two satellites are different from the ground observation data. To improve the quality of retrieved insolations, we have reproduced surface insolation of each satellite through adjustment of the Cloud Factor, and the Cloud Factor for GOES-9 satellite is modified based on the analysis result of difference channel data. As a result, the insolations estimated from GOES-9 for cloudy conditions show good agreement with MTSAT-1R and ground observation : RMSE=$83.439W\;m^{-2}$ Bias=$27.296W\;m^{-2}$. The result improved accuracy confirms that the modification of Cloud Factor for GOES-9 can improve the continuity and consistency of the insolations derived from two or more satellites.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.494-503
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• 1995

The selection of salt tolerant rice variety needs an effective method in its testing. Salinity of irrigated water, 0.5% at seedling stage, 0.6% at tillering stage, and 0.9% at panicle formation stage were treated to test salt tolerance of rice using 45 cultivars. At tillering stage, salty water irrigation reduced plant height to 22.6% in early maturing rices(EMR), 30.5% in medium maturing rices(MMR), and 20.9% in medium-late maturing rices(MLMR), and also reduced number of tillers to 11.2% in EMR, 36.2% in MMR, and 36.0% in MLMR compared to rices grown in non-salty water irrigation. At panicle formation stage of rice, salty water irrigation affected plant height and tiller numbers that showed varietal differences. As salt tolerant rice cultivars, Daegwangbyeo, Namweonbyeo, Sinseonchalbyeo, Gyehwabyeo, and Daeyabyeo were selected. Jinbubyeo, Donghaebyeo, and Tamjinbyeo were weak in salty water irrigation.

• Journal of Intelligence and Information Systems
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• v.23 no.2
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• pp.39-70
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• 2017

Data-drive analytics techniques have been recently applied to public surveys. Instead of simply gathering survey results or expert opinions to research the preference for a recently launched product, enterprises need a way to collect and analyze various types of online data and then accurately figure out customer preferences. In the main concept of existing data-based survey methods, the sentiment lexicon for a particular domain is first constructed by domain experts who usually judge the positive, neutral, or negative meanings of the frequently used words from the collected text documents. In order to research the preference for a particular product, the existing approach collects (1) review posts, which are related to the product, from several product review web sites; (2) extracts sentences (or phrases) in the collection after the pre-processing step such as stemming and removal of stop words is performed; (3) classifies the polarity (either positive or negative sense) of each sentence (or phrase) based on the sentiment lexicon; and (4) estimates the positive and negative ratios of the product by dividing the total numbers of the positive and negative sentences (or phrases) by the total number of the sentences (or phrases) in the collection. Furthermore, the existing approach automatically finds important sentences (or phrases) including the positive and negative meaning to/against the product. As a motivated example, given a product like Sonata made by Hyundai Motors, customers often want to see the summary note including what positive points are in the 'car design' aspect as well as what negative points are in thesame aspect. They also want to gain more useful information regarding other aspects such as 'car quality', 'car performance', and 'car service.' Such an information will enable customers to make good choice when they attempt to purchase brand-new vehicles. In addition, automobile makers will be able to figure out the preference and positive/negative points for new models on market. In the near future, the weak points of the models will be improved by the sentiment analysis. For this, the existing approach computes the sentiment score of each sentence (or phrase) and then selects top-k sentences (or phrases) with the highest positive and negative scores. However, the existing approach has several shortcomings and is limited to apply to real applications. The main disadvantages of the existing approach is as follows: (1) The main aspects (e.g., car design, quality, performance, and service) to a product (e.g., Hyundai Sonata) are not considered. Through the sentiment analysis without considering aspects, as a result, the summary note including the positive and negative ratios of the product and top-k sentences (or phrases) with the highest sentiment scores in the entire corpus is just reported to customers and car makers. This approach is not enough and main aspects of the target product need to be considered in the sentiment analysis. (2) In general, since the same word has different meanings across different domains, the sentiment lexicon which is proper to each domain needs to be constructed. The efficient way to construct the sentiment lexicon per domain is required because the sentiment lexicon construction is labor intensive and time consuming. To address the above problems, in this article, we propose a novel product reputation mining algorithm that (1) extracts topics hidden in review documents written by customers; (2) mines main aspects based on the extracted topics; (3) measures the positive and negative ratios of the product using the aspects; and (4) presents the digest in which a few important sentences with the positive and negative meanings are listed in each aspect. Unlike the existing approach, using hidden topics makes experts construct the sentimental lexicon easily and quickly. Furthermore, reinforcing topic semantics, we can improve the accuracy of the product reputation mining algorithms more largely than that of the existing approach. In the experiments, we collected large review documents to the domestic vehicles such as K5, SM5, and Avante; measured the positive and negative ratios of the three cars; showed top-k positive and negative summaries per aspect; and conducted statistical analysis. Our experimental results clearly show the effectiveness of the proposed method, compared with the existing method.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.80-90
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• 2004

Three experiments were performed to test the assumption that imbalanced dietary amino acid mixtures must lead to increased heat production (HP). The first experiment was based on diets formulated to have a wide range of crude protein (CP) concentrations but a fixed concentration of lysine, formulated to be the first-limiting amino acid. In the second (converse) experiment, lysine concentration was varied over a wide range while CP content was kept constant. To prevent the masking of dietary effects by thermoregulatory demands, the third experiment was performed at 30 $^{\circ}C$ with the diets similar to the diets used in the second experiment. The detailed relationships among amino acid balance, nitrogen (N) metabolism and energy (E) metabolism were investigated in a computer-controlled chamber calorimetry system. The results of experiments were compared with the predictions of a computerised simulation model of E metabolism. In experiment 1. with constant lysine and varying CP, there was a 75 % increase in N intake as CP concentration increased. This led to a 150 % increase in N excretion. with no significant change in HP. Simulated HP agreed with the empirically determined results in not showing a trend with dietary CP. In experiment 2, with varying lysine but constant CP, there was a 3-fold difference in daily weight gain between the lowest and highest lysine diets. HP per bird increased significantly with dietary lysine concentration. There was still an effect when HP was adjusted for body weight differences, but it failed to maintain statistical significance. Simulated HP results agreed in showing little effect of varying lysine concentration and growth rate on HP. Based on the results of these two experiments, the third experiment was designed to test the response of birds to dietary lysine in high ambient temperature. In experiment 3 which performed at high ambient temperature (30 $^{\circ}C$), HP per bird increased significantly with dietary lysine content, whether or not adjusted for body-weight. The trend was greater than in the previous experiment (20 $^{\circ}C$).

• Korean journal of applied entomology
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• v.54 no.4
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• pp.383-392
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• 2015

We investigated the induction of pupal diapause and number of generation for H. armigera using outdoor rearing and sex pheromone trapping in Suwon, Korea. Over-wintering pupae were induced when neonate larvae were reared in the outdoors from late Aug. to early Oct. in 2013 and 2014. H. armigera adults emerged from late May to early Jun. for 2013 colonies and from late May to late Jun. for 2014 colonies. The colonies placed after mid September produced only diapause pupae, to show environmental conditions that day-lengths on the rearing start date were 11 h 49 min~12 h 24 min, and mean temperatures before pupation were $14.8{\sim}20.7^{\circ}C$. Summer diapause was not observed in all colonies. The peak occurrence of H. armigera adults from sex pheromone trap in Suwon and Hwaseong were pooled and showed four generations (1st: from late Apr. to mid Jun., 2nd: from mid Jun. to late Jul., 3rd: from mid Jul. to late Aug., 4th: from late Aug. to mid Oct.). A degree-day model for development of H. armigera developed by Mironidis and Savopoulou-Soultani (2008) was used to validate the number of generation from field observations using pheromone traps. The 3rd and over-wintering generations were mainly overlapped. It was decided that H. armigera has one over-wintering and three complete generations in a year, and diapause is induced from offsprings of the 3rd and 4th generations adults. It is expected that larvae of the 1st and 2nd generations give a damage to ear zone in maize fields in which have been planted during April.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.119-130
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• 2004

Decrease in cardiac function after open heart surgery is due to an ischemia induced myocardial damage during surgery, and ischemic preconditioning, a condition in which the myocardial damage does not accumulate after repeated episodes of ischemia but protects itself from damage after prolonged ischemia due to myocytes tolerating the ischemia, is known to diminish myocardial damage, which also helps the recovery of myocardium after reperfusion, and decreases incidences of arrythmia. Our study is performed to display the ischemic preconditioning and show the myocardial protective effect by applying cardioplegic solution to the heart removed from rat. Material and Method: Sprague-Dawley male rats were used, They were fixed on a modified isolated working heart model after cannulation. The reperfusion process was according to non-working and working heart methods and the working method was executed for 20 minutes in which the heart rate, aortic pressure, aortic flow and coronary flow were measured and recorded. The control group is the group which the extracted heart was fixed on the isolated working heart model, recovered by reperfusion 60 minutes after infusion and preserved in the cardioplegic solution 20 minutes after the working heart perfusion and aortic cross clamp, The thesis groups were divided into group I, which ischemic hearts that were hypoxia induced were perfused by cardioplegic solution and preserved for 60 minutes; group II, the cardioplegic solution was infused 45 seconds (II-1), 1 minutes (II-2), 3 minutes (II-3), after the ischemia induction, 20 minutes after working heart perfusion and aortic cross clamp; and group III, hearts were executed on working heart perfusion for 20 minutes and aortic cross clamp was performed for 45 seconds (III-1), 1minute (III-2), 3 minutes (III-3), reperfused for 2 minutes to recover the heart, and then aortic cross clamping was repeated for reperfusion, all the groups were compared based on hemodynamic performance after reperfusion of the heart after preservation for 60 minutes. Result: The recovery time until spontaneous heart beat was longer in groups I, II-3, III-2 and III-3 to control group (p<0.01). Group III-1 (p<0.05) had better results in terms of recovery in number of heart rates compared to control group, and recovered better compared to II-1 (p<0.05). The recovery of aortic blood pressure favored group III-1 (p<0.05) and had better outcomes compared with II-1 (p<0.01). Group III-1 also showed best results in terms of cardiac output (p<0.05) and group III-2 was better compared to II-2 (p<0.05). Group I (p<0.01) and II-3 (p<0.05) showed more cardiac edema than control group. Conclusion: When the effects of other organs are dismissed, protecting the heart by infusion of cardioplegic solution after enforcing ischemia for a short period of time before the onset of abnormal heart beats for preconditioning has a better recovery effect in the cardioplegic group with preconditioning compared to the cardioplegic solution itself. we believe that further study is needed to find a more effective method of preconditioning.

• Journal of the Korean Chemical Society
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• v.65 no.3
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• pp.197-202
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• 2021

In this study, activated clay treated with H₂SO₄ (20% by weight) and heat at 90 ℃ for 8 h for acid white soil was used as an adsorbent for the removal of PO₄^3--P in water. Prior to the adsorption experiment, the characteristics of activated clay was examined by X-ray Fluorescence Spectrometry (XRF) and BET surface area analyser. The adsorption of PO₄^3--P on activated clay was steeply increased within 0.25 h and reached equilibrium at 4 h. At 5 mg/L of low PO₄^3--P concentration, roughly 98% of adsorption efficiency was accomplished by activated clay. The adsorption data of PO₄^3--P were introduced to the adsorption isotherm and kinetic models. It was seen that both Freundlich and Langmuir isotherms were applied well to describe the adsorption behavior of PO₄^3--P on activated clay. For adsorption PO₄^3--P on activated clay, the Freundlich and Langmuir isotherm coefficients, K_F and Q, were found to be 8.3 and 20.0 mg/g, respectively. The pseudo-second-order kinetics model was more suitable for adsorption of PO₄^3--P in water/activated clay system owing to the higher correlation coefficient R² and the more proximity value of the experimental value q_e,exp and the calculated value q_e,cal than the pseudo-first-order kinetics model. The results of study indicate that activated clay could be used as an efficient adsorbent for the removal of PO₄³-P from water.