• Resources Recycling
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• v.19 no.4
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• pp.51-57
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• 2010

As a recycling of Si sludge from Si wafer process, a Si-SiC-CuO-C composite material was synthesized and investigated as an anode material for lithium batteries. The Si sludge consisted of Si, SiC, machine oil, and metallic impurities. The oil and metal impurities was removed by organic washing, magnetic separation, and acid washing. The Si-SiC-CuO-C composite from the recovered Si-SiC mixture was prepared by high-energy mechanical milling. According to the electrochemical tests such as charge-discharge capacity and cycling behavior, it showed the improved cycle performance. The SiC and CuO-related phases were presumed to restrain the volume expansion of the anode and Fe, however, should be removed below 10 ppm prior to synthesis of the composite because it caused the capacity loss of the active material itself.

• Nutrition Research and Practice
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• v.6 no.4
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• pp.366-374
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• 2012

In order to create a worker-friendly environment for institutional foodservice, facilities operating with a dry kitchen system have been recommended. This study was designed to compare the work safety and work environment of foodservice between wet and dry kitchen systems. Data were obtained using questionnaires with a target group of 303 staff at 57 foodservice operations. Dry kitchen facilities were constructed after 2006, which had a higher construction cost and more finishing floors with anti-slip tiles, and in which employees more wore non-slip footwear than wet kitchen (76.7%). The kitchen temperature and muscular pain were the most frequently reported employees' discomfort factors in the two systems, and, in the wet kitchen, "noise of kitchen" was also frequently reported as a discomfort. Dietitian and employees rated the less slippery and slip related incidents in dry kitchens than those of wet kitchen. Fryer area, ware-washing area, and plate waste table were the slippery areas and the causes were different between the functional areas. The risk for current leakage was rated significantly higher in wet kitchens by dietitians. In addition, the ware-washing area was found to be where employees felt the highest risk of electrical shock. Muscular pain (72.2%), arthritis (39.1%), hard-of-hearing (46.6%) and psychological stress (47.0%) were experienced by employees more than once a month, particularly in the wet kitchen. In conclusion, the dry kitchen system was found to be more efficient for food and work safety because of its superior design and well managed practices.

• Journal of Biomedical Engineering Research
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• v.44 no.2
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• pp.147-156
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• 2023

Efforts to employ smart home sensors to monitor the indoor activities of elderly single residents have been made to assess the feasibility of a safe and healthy lifestyle. However, the bathroom remains an area of blind spot. In this study, we have developed and evaluated a new edge computer device that can automatically detect water usage activities in the bathroom and record the activity log on a cloud server. Three kinds of sound as flushing, showering, and washing using wash basin generated during water usage were recorded and cut into 1-second scenes. These sound clips were then converted into a 2-dimensional image using MEL-spectrogram. Sound data augmentation techniques were adopted to obtain better learning effect from smaller number of data sets. These techniques, some of which are applied in time domain and others in frequency domain, increased the number of training data set by 30 times. A deep learning model, called CRNN, combining Convolutional Neural Network and Recurrent Neural Network was employed. The edge device was implemented using Raspberry Pi 4 and was equipped with a condenser microphone and amplifier to run the pre-trained model in real-time. The detected activities were recorded as text-based activity logs on a Firebase server. Performance was evaluated in two bathrooms for the three water usage activities, resulting in an accuracy of 96.1% and 88.2%, and F1 Score of 96.1% and 87.8%, respectively. Most of the classification errors were observed in the water sound from washing. In conclusion, this system demonstrates the potential for use in recording the activities as a lifelog of elderly single residents to a cloud server over the long-term.

• Korean Journal of Computational Design and Engineering
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• v.15 no.3
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• pp.222-233
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• 2010

Developed in this research is a TP (tangible prototyping) system, which consists of two modules; (1) a virtual reality model to evaluate the functions and appearance of the product, and (2) a haptic device to emulate tactile and kinesthetic properties of mechanical dial knobs. As an example, a washing machine is modeled using a commercial CAD system and transformed in VRML and X3D formats. Some dynamic behaviors and kinematic characteristics are programmed using X3D script and Java. Various haptic behaviors of the dial are generated by modulating torque profile according to the rotation angle. A torque profile measuring system is developed to evaluate the behaviors of the haptic dial physically. Haptic sensibility evaluations are accomplished using the TP by semantic differential method.

• Textile Coloration and Finishing
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• v.32 no.2
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• pp.80-88
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• 2020

Supercritical fluid dyeing is a new alternative to the conventional aqueous process because of its environmental benefits. In this study, dyeing properties of Nylon 6 fabrics were investigated depending on dyeing temperature and pressure in supercritical CO₂ fluid dyeing system. In order to select the optimal condition for supercritical fluid dyeing of Nylon 6 fabrics, dyeing temperature and pressure were varied from 100, 110, 120℃, 200, 230, 260bar, respectively. The results of K/S values and levelling properties showed that the optimal dyeing condition for Nylon 6 fabrics was 110℃ and 230bar in the supercritical CO₂ fluid dyeing system. The washing fastness ratings of the dyed Nylon 6 fabrics under supercritical medium were good for both fading and staining except for staining on nylon.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.191-193
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• 1991

This paper is described about the on-line, real-time quality information management system as the infrastructure of CIM, which we developed for the full automatic washing machine assembly line. This System is composed of Ethernet LAN, RS-485 Network, POP terminal, BAR CODE Scanner, PLC, ROBOT, measuring equipments and real-time processing software. We will run this system from next month regularly.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.78-84
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• 2005

The development of eco-friendly low pressure carburizing system with high pressure gas quenching (LPC_GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.5
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• pp.800-808
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• 1997

Decision process for length dimension in the mechanical system design process has been studied with a washing machine transmission as a model. The results are, (i) the length dimensions of the non-shaft elements are independent of other elements, (ii) the length dimensions of the shaft elements are dependent on the dimensions of the non-shaft elements located inside and outside of that elements, (iii) the length dimensions of the inner shaft elements are dependent on those of the outer shaft elements located parallel, (iv) the length dimensions of the shaft elements located serial are independent of each other.

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.1-7
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• 2010

The five new red disperse dyes for unmodified pure polypropylene fibers were synthesized. As a coupling component, a di-n-hexyl substituent was used in common, while various substituents were used for the diazo component. The dye having electron donating group at diazo component showed hypsochromic shift compared to the unsubstituted dye, while the dyes having electron withdrawing groups showed bathochromic shift. Owing to their extreme hydrophobicity caused by the di-n-hexyl substituent, all dyes exhibited very high affinity toward pure polypropylene fibers. Fastness to washing was very good for all dyes and fastness to light was good except two purplish red dyes.

• Textile Coloration and Finishing
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• v.28 no.3
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• pp.156-163
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• 2016

The 6 novel super hydrophobic bluish-green dyes, showing the maximum absorption at 600~650nm, were synthesized to dye polyolefin fibers such as polypropylene and high strength polyethylene fibers. Their absorption spectra appeared almost the same at visible range, which meant the length of alkyl substituents did not affect on color appearance of the dyes. The optimum length of alkyl group was determined as hexyl substituents from the practical point of view. From the dyeing results, the optimum dyeing condition was $130^{\circ}C$ for 1 hour. The good fastness ratings to washing, rubbing were obtained showing 4-5 for both fibers. Light fastness was obtained also good rating 4 for both fibers.