• Korean Chemical Engineering Research
• /
• v.59 no.2
• /
• pp.191-199
• /
• 2021

A distillation column, which is a main facility of the chemical process, separates the desired product from a mixture by using the difference of boiling points. The distillation process requires the optimization and the prediction of operation because it consumes much energy. The target process of this study is difficult to operate efficiently because the composition of feed flow is not steady according to the supplier. To deal with this problem, we could develop a data-driven model to predict operating conditions. However, data preprocessing is essential to improve the predictive performance of the model because the raw data contains outlier and noise. In this study, after optimizing the predictive model based long-short term memory (LSTM) and Random forest (RF), we used a low-pass filter and one-class support vector machine for data preprocessing and compared predictive performance according to the method and range of the preprocessing. The performance of the predictive model and the effect of the preprocessing is compared by using R2 and RMSE. In the case of LSTM, R2 increased from 0.791 to 0.977 by 23.5%, and RMSE decreased from 0.132 to 0.029 by 78.0%. In the case of RF, R2 increased from 0.767 to 0.938 by 22.3%, and RMSE decreased from 0.140 to 0.050 by 64.3%.

• Resources Recycling
• /
• v.29 no.6
• /
• pp.3-14
• /
• 2020

This study aims to introduce and review on the recovery technologies of rare earth elements(REEs) from coal ash. Many researchers have been carried out by various beneficiation processes, such as particle size separation, magnetic separation, specific gravity, and flotation to recover rare earth elements from coal ash generated from Pulverized Coal(PC) boiler. Through the beneficiation process, it was confirmed that concentration of rare earth elements was much lower than the 4,700 ppm, and that additional enrichment treatment through wet process was needed for the products recovered after the beneficiation process. It was confirmed that the rare earth elements contained in coal ash were applied to the leaching process after pretreatment such as alkali-fusion to improve leaching efficiency. Although beneficiation and leaching methods have been studied, its optimum recovery technologies for rare earth elements not been confirmed up to now, research on the recovery of rare earth contained in coal ash is reported to continue. In case of Korea, the technology for the recovery of rare earth elements from coal ash and coal by-product could not been confirmed up to present. In these reasons, it is urgent to develop technologies such as beneficiation and leaching process continuously.

• Journal of Internet of Things and Convergence
• /
• v.8 no.6
• /
• pp.27-33
• /
• 2022

Sleep is an essential factor for living a healthy life, but most modern people complain of poor sleep. For these people, as the need for a means to simply evaluate and manage the quality of sleep increases, devices that can check the sleep state at home without monitoring by an examiner are being developed. The smart sleep mask, which is the subject of this usability test, provides bio-signal monitoring while sleeping so that you can conveniently measure and manage your sleep state for yourself. The purpose of this study is to evaluate the usability and safety of the smart sleep mask, to find and prevent potential factors related to errors in use that may occur, and to develop the comfort and safety of this product. As a result of the formative evaluation of the sleep mask prototype, it was reported that it was difficult to turn on the power and check the results, and that the sleep mask was not comfortable to wear. Different opinions were presented on the size and weight of the sleeping mask by people in different age groups.

• Food Science and Industry
• /
• v.50 no.2
• /
• pp.2-11
• /
• 2017

Packaging is the last defensive barrier that protects food products from insect infestation during storage. However, though packaging films are hermetically sealed, insects can still be attracted by strong olfactory cues and penetrate through packaging materials, resulting in contamination. Insect contamination may cause consumers to be repulsed by contaminated food products. Especially, it is well known that stored-product insects cause critical problems in the cereal industry by inducing quantitative and qualitative damages to the grain products. The contaminations are caused by insects' metabolic byproducts and body parts, consequentially caused customer repulsion. Therefore, it is necessary to repel and control insects. However, management systems for storage insects in food industry have been inadequate for many years. Synthetic pesticides has been widely used, but pesticides may accumulate in foods, causing acute and chronic symptoms in consumers. For this reason, there is a growing need for the development of natural insecticides that can replace synthetic pesticides. Thus, various reports about anti-insect packaging materials and strategies to repel insects were introduced in this study. Furthermore, we suggested new strategies to develop an insect-repelling active packaging materials which could be applied in the food packaging industry.

• International Area Studies Review
• /
• v.14 no.2
• /
• pp.181-204
• /
• 2010

This study researched relationship between R&D capability(TC), Network capability(NC), International marketing activity(IMA) and effect to performance of Korean globalizing INNOBIZs. In former research, they found out that TC, NC, IMA effect to performance directly. But they didn't focus on the relationship between the variables and Korean INNOBIZs. Recently, Global environment of competition is getting more and more complicated. So even the companies develop the excellent product, the companies can not get superior performance than competitor as long as the company combine with IMA or NC. In this study, empirical analysis performed using covariance structural analysis for Korean INNOBIZs. As we know in former research, TC and IMA have a positive effect on performance directly. But NC does not have a direct effect on performance. Also we found out TC and NC intermediated by MC have positive effect on performance. This result is theoretically and practically suggestive that using the company developed NC in International IMA effect on Performance.

• The Korea Journal of Herbology
• /
• v.36 no.1
• /
• pp.9-17
• /
• 2021

Objectives : Tetrapanacis Medulla and Akebiae Caulis are one of the most frequently adulterated herbal medicines because of their confusability of terms in the ancient writings and the similarity of morphological features of dried herbal products. The major adulterant is Aristolochia manshuriensis (Guanmutong) which has a serious safety concern with its toxicity. To ensure the safety and quality of the two herbal medicines, it is necessary to discriminate the toxic adulterant from authentic species. The aim of this study is to develop SCAR markers and to establish the multiplex-SCAR assay for discrimination of four plant species related to Tetrapanacis Medulla and Akebiae Caulis. Methods : ITS regions of fifteen samples of four species (Tetrapanax papyrifer, Fatsia japonica, Aristolochia manshuriensis, and Akebia quinata) collected from different sites were amplified and sequenced. Fifteen obtained ITS sequences were aligned and analysed for the detection of species-specific sequence variations. The SCAR markers were designed based on the sequence alignments and then, multiplex-SCAR assay enhancing rapidity was optimized. Results : ITS sequences clearly distinguished the four species at the species level. The developed SCAR markers and multiplex-SCAR assay were successfully discriminated four species and detected the adulteration of commercial product samples by comparison of the amplified DNA fragment sizes. Conclusions : These SCAR markers and multiplex-SCAR assay are a rapid, simple, and reliable method to identify the authentic Tetrapanacis Medulla and Akebiae Caulis from adulterants. These genetic tools will be useful to ensure the safety and to standardize the quality of the two herbal medicines.

• Applied Chemistry for Engineering
• /
• v.33 no.1
• /
• pp.83-89
• /
• 2022

Since the pandemic of COVID-19, active investigation to develop immunity to infectious disease by delivering nucleic acids has been proceeded. Particularly, many studies have been conducted on non-viral vector as several vital side-effects which were found on nucleic acid delivery system using viral vectors. In this study, we have developed plasmid DNA (pDNA) loaded-hyaluronic acid derivative (HA) coated-polyethyleneimine (PEI) based polyplex for enhanced nucleic acid delivery efficiency. We have optimized the ratio of pDNA : PEI : HA by measuring size and protein transcription efficiency. The final product, polyplex-HA, was characterized through measuring size, zeta-potential and TEM image. Intracellular uptake and protein transcription efficiency were compared to commercially available transfection reagent, lipofectamine, through fluorescence image and flow cytometry. In conclusion, polyplex-HA presents a novel gene delivery system for efficient and stable protein transcription since it is available for delivering various genetic materials and has less immunoreactivity.

• Smart Media Journal
• /
• v.10 no.4
• /
• pp.54-62
• /
• 2021

As the volume of online e-commerce transactions increases, items diversify and the classification becomes complicated. E-commerce platforms that specialize in dealing only in one area are emerging, and the area is diversifying. Three problems were identified by researching the craft online e-commerce platform, one of the various types of professional e-commerce platforms. First of all, although craft materials are diversified and complex on the platform, the existing craft e-commerce system is fragmented in structure to categorize complex crafts, making it difficult to accurately present search results that meet various criteria. Second, although appearance is the main reason for purchasing artifacts, it is rare for users to categorize them according to appearance, so they have to judge and filter each work directly. Finally, the language entered when searching for artifacts by non-technical experts is not reflected in the language used to categorize artifacts in the taxonomic system, so the language used for searching is highly accurate. Therefore, the purpose of this study is to add and consider complex attributes in the field of technology to meet the search criteria. Properties to be added must include the main appearance in the search for artifacts. In addition, the government aims to develop a taxonomic system that can reflect non-experts' search languages in the search of works through artificial intelligence natural language processing technology.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.54 no.6
• /
• pp.880-889
• /
• 2021

The home meal replacement (HMR) market has attracted significant attention due to COVID-19 pandemic and products that utilize the combination of different processed ingredients are now being developed. In this study, Broughton's ribbed ark Scapharca broughtonii was soaked in seasoned soy sauce with the incorporation of mustard leaf Brassica juncea (M-BRA), which is known to have a unique texture as well as excellent functional properties such as antioxidation, to develop a regional specialty product. The optimal conditions for manufacturing M-BRA from the seasoned soy sauce (the sauce to be added [X₁] and the soaking time [X₂]), were examined using response surface methodology (RSM) to analyze the significance of the salinity (Y₁), amino-N content (Y₂), and overall acceptance (Y₃). The coefficient of determination (R²) between X₁-X₂ and Y₁-Y₃ were close to 1, thereby confirming the suitability of the RSM model. The optimal conditions were seasoned soy sauce addition of 140% and soaking time of 156 min. The M-BRA manufactured under these conditions exhibited superior overall acceptance compared to seasoned commercial soy sauce, which was used as a control. We expect that the market for M-BRA manufactured by combining marine and agricultural materials will expand owing to superior overall acceptance compared with commercial products.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.2
• /
• pp.153-161
• /
• 2022

Physical activities are decreasing and sitting time is increasing due to the automation, smartization, and intelligence of necessary household items throughout daily life. Recent healthcare studies have reported that the likelihood of obesity, diabetes, cardiovascular disease, and early death increases in proportion to sitting time. In this paper, we develop a sitting posture correction cushion in real time using capacitive pressure sensor based on conductive textile. It develops a pressure sensor using conductive textile, a key component of the posture correction cushion, and develops a low power-based pressure measurement circuit. It provides a function to transmit sensor values measured in real time to smartphones using BLE short-range wireless communication on the posture correction cushion, and develops a mobile application to check the condition of the sitting posture through these sensor values. In the mobile app, you can visualize your sitting posture and check it in real time, and if you keep it in the wrong posture for a certain period of time, you can notify it through an alarm. In addition, it is possible to visualize the sitting time and posture accuracy in a graph. Through the correction cushion in this paper, we experiment with how effective it is to correct the user's posture by recognizing the user's sitting posture, and present differentiation and excellence compared to other product.