• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3658-3679
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• 2022

Classification of persons wearing and not wearing face masks in images has emerged as a new computer vision problem during the COVID-19 pandemic. In order to address this problem and scale up the research in this domain, in this paper a hybrid technique by employing ResNet-101 and multi-layer perceptron (MLP) classifier has been proposed. The proposed technique is tested and validated on a self-created face masks classification dataset and a standard dataset. On self-created dataset, the proposed technique achieved a classification accuracy of 97.3%. To embrace the proposed technique, six other state-of-the-art CNN feature extractors with six other classical machine learning classifiers have been tested and compared with the proposed technique. The proposed technique achieved better classification accuracy and 1-6% higher precision, recall, and F1 score as compared to other tested deep feature extractors and machine learning classifiers.

• Journal of Information Technology Services
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• v.20 no.5
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• pp.89-104
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• 2021

Food delivery service combined with IT technology and HMR (Home Meal Replacement) are rapidly growing due to the COVID-19. Recently, the demand for salads along with HMR has increased among office workers in their 20s and 30s who are interested in health and beauty. Freshcode is a food startup with 6 years of experience that started selling salad products through O2O service. Freshcode applied for a patent for a service that collects orders from nearby areas and delivers them on the same day to a designated delivery address 'FCOSPOT' to save shipping costs. In March 2021, in recognition of the growth potential of the regular delivery service, Freshcode received an investment of 6 billion won in Series A. This study may have practical implications to early-stage startups and scale-up stage startups through a longitudinal case study on the growth of a single company. As for the research method, the lean startup methodology and lean canvas were used in the early stage of startup. In particular, the process of the build-measure and learn feedback-loop, which is the core of lean startup methodology, was applied to each major decision-making step. In the scale-up stage after 5 years, the business model canvas was used to schematize the growth as a food online O2O platform to verify continuous innovation. This case study has three main findings. First, the idea of 'FCOSPOT' was successfully implemented through the Lean Startup methodology. Second, Freshcode demonstrated the scalability of the differentiated business model of shared base delivery O2O. Third, a key factor of success was the digital integrated communication operation strategy that maximizes the experience for the created customers.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.793-803
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• 2021

The small PWR has been paid more and more attention due to its diversity of application and flexibility in the site selection. However, the large core power density, the small containment space and the rapid accident progress characteristics make it difficult to control the containment pressure like the traditional PWR during the LOCA. The pressure suppression system has been used by the BWR since the early design, which is a suitable technique that can be applied to the small PWR. Since the configuration and operating conditions are different from the BWR, the pressure suppression system should be redesigned for the small PWR. Conducting the experiments on the scale down test facility is a good choice to reproduce the prototypical phenomena in the test facility, which is both economical and reasonable. A systematic scaling method referring to the H2TS method was proposed to determine the geometrical and thermohydraulic parameters of the pressure suppression containment response test facility for the small PWR conceptual design. The containment and the pressure suppression system related thermohydraulic phenomena were analyzed with top-down and bottom-up scaling methods. A set of the scaling criteria were obtained, through which the main parameters of the test facility can be determined.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.7
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• pp.2328-2344
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• 2022

2D human pose estimation still faces difficulty in low-resolution images. Most existing top-down approaches scale up the target human bonding box images to the large size and insert the scaled image into the network. Due to up-sampling, artifacts occur in the low-resolution target images, and the degraded images adversely affect the accurate estimation of the joint positions. To address this issue, we propose a multi-resolution input feature fusion network for human pose estimation. Specifically, the bounding box image of the target human is rescaled to multiple input images of various sizes, and the features extracted from the multiple images are fused in the network. Moreover, we introduce a guiding channel which induces the multi-resolution input features to alternatively affect the network according to the resolution of the target image. We conduct experiments on MS COCO dataset which is a representative dataset for 2D human pose estimation, where our method achieves superior performance compared to the strong baseline HRNet and the previous state-of-the-art methods.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.303-309
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• 1994

To develop the treatment process of swine wastewater using Rhodopseudomonas palustris KK14 with high utilizable ability of organic acids, some operating conditions were investigated and optimized in flask-scale and laboratory-scale reactors. The optimal operating conditions in photosynthetic bacteria (PSB) reactor of semi-continuous type were obtained at HRT 6 day, 5% (v/v/day) seeding rate of PSB sludge and 10% (v/v/day) returning rate of PSB return sludge. Under the above operating condition, COD level of the wastewater (initial COD: 10 g/l) was reduced to about 1.7 g/l after 4 days treatment and MLSS was held constant at $4{\sim}5\;g$ per liter. In laboratory-scale process consisted of 5.2 l anaearobic digestion reactor and 15 l PSB reactor, the total removal rates of COD and BOD were increased to 95% and 96% by the continuous operation for 5.36 days, respectively, showing $3kg\;COD/m^3/day$ COD loading rate and 1.1 Kg COD/Kg MLSS/day sludge loading rate in PSB reactor. The offensive odor was considerably removed through the treatment process of swine wastewater.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.3
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• pp.233-244
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• 2008

A conceptual design study for a pyroprocesing facility, has been carried out in this study, which is available for the recovery of uranium and transuranic elemental group(TRU), that is, reusable as a nuclear fuel especially in a next generation-type reactor. The scale of this facility has been chosen as 20 kg HM/batch, comparatively small engineering size in order to collect scale-up data for the design of a commercial facility as well as to get operational experience. The spent fuel to be handled in this process is as follows : 3.5 % enriched uranium fuel, 35,000MWd/tU and 5-year cooled. The major items considered in the conceptual study are a building lay-out including various hot cells, safety management of the process operation in conjunction with material balance control, radiation safety, inert atmosphere control in shielded hot cells, and criticality control of uranium and TRU products.

• KSBB Journal
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• v.23 no.6
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• pp.470-473
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• 2008

A pilot-plant biofilter ($1750\;m\;W{\times}2750\;mm\;L{\times}2000\;mm\;H$) packed with polyurethane foam ($20\;m\;W{\times}20\;mm\;L{\times}20\;mm\;H$) was installed in an pharmaceutical plant emitting gas streams containing n-hexane and alcohols. The biofilter was successfully operated for 74 days under highly fluctuating incoming concentrations at a residence time of 12.8-24.8 sec. Alcohols and n-hexane were removed by more than 90% from 5 and 20 days after start up, respectively. Malodor was also removed more than 95% from 20 days after start up.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.108-114
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• 2001

Petri nets have been introduced as a powerful analyzing and design tool for the discrete systems such as sequential control systems. However, one of the important problems in its applications is that the model can be analyzed hardly when we deal with large scale systems because of increase of the number of Petri net components. To overcome this problem, some methods for dividing or reducing of Petri net have been suggested. In this paper, an approach for hierarchical expression of Petri net based on Sequential function Chart(SFC) and Bottom Up oriented Mehodology(BUM) is proposed. Especially, some definitions and rules are defined in order to divide and compose sub Petri nets. A measuring tank system will be described as a typical kind of discrete systems and modeled by some sub Petri nets based on the SFC and BUM by the proposed method in this paper.

• Clean Technology
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• v.17 no.3
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• pp.250-258
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• 2011

Thermal plasma has been presented for the decomposition of perfluorocompounds (PFCs) which are extensively used in the semiconductor manufacturing and display industry. We developed pilot-scale equipment to investigate the large scale treatment of PFCs and called it a "thermal plasma scrubber". PFCs such as $CF_4$, $C_2F_6$, $SF_6$, and $NF_3$ used in experiments were diluted with $N_2$. There were two different types of experiment setup related to the water spray direction inside the thermal plasma scrubber. The first type was that the water was sprayed directly into the gas outlet located at the exit of the reaction section. The second type was that the water was sprayed on the wall of the quenching section. More effective decomposition took place when the water was sprayed on the quenching section wall. For $C_2F_6$, $SF_6$, and $NF_3$ the maximum destruction and removal efficiency was nearly 100%, and for $CF_4$ was up to 93%.

• Journal of Dairy Science and Biotechnology
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• v.37 no.3
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• pp.167-176
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• 2019

Milk contains essential nutrients and functional compounds, such as calcium, fat-soluble vitamins A, D, E, and K, carotenoids, bioactive peptides, and sphingolipids. The bioactive molecules from milk are not expensive and have an added advantage of being derived from food. Therefore, they are more stable and have a broader spectrum than that of other chemicals. Bioactive milk components are useful for treating non-digestive tract disorders, such as cancer, cognitive decline, and hypertension. However, the clinical application of certain breast milk ingredients is limited due to the lack of a large-scale production technology. Once the scaled-up production of lactoferrin became possible, clinical applications were devised and evaluated. Similarly, human alpha-lactalbumin made lethal to tumor cells (HAMLET) can be produced on a large scale as a recombinant protein in microorganisms or in transgenic cattle using suitable separation systems. HAMLET can be used to treat human skin papilloma and cancer. Studies on breast milk that explored the clinical applications of the bioactive components of breast milk have spurred the development of translational medicine and breast milk-derived therapeutics. Some breast-milk derived therapeutic agents are already available to clinicians. Many components of breast milk have shown efficacy in pre-clinical studies and have valid clinical evaluations.