• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.270-274
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• 2001

With Increasing importance of electroless nickel plating technology in many fields such as electronic and automobile industries, the treatment of the spent baths is becoming a serious problem. These spent baths contain iron and zinc as impurities, organic acids as complexing reagents, and phosphonate ions as oxidized species of tile reducing reagent. as well as several grams per liter of nickel. The spent baths are currently treated by conventional precipitation method. but a mettled with no sludge generation is desired. This work aims at establishing a recycling process of nickel from tile spent baths using solvent extraction. Extraction behaviors of nickel. iron. and zinc in various 쇼pes of real spent baths are investigated as a function of pH using LIX841, di (2-ethylhexyl)phosphoric acid (D2EHPA), and PC88A as tile extractants. Nickel is extracted by LIX84I at the equilibrium pH of more than 6 with high efficiency. For the weakly acid baths. iron and zinc are extracted by D2EHPA or PC88A without adjusting the pH of the baths leaving nickel in the aqueous phase. Stripping of nickel from LIX84I with sulfuric acid is also investigated. It is shown that concentrated nickel sulfate solution (> 100 ㎏-Ni/㎥) is obtained. This solution can be reused in the electroless plating process. Based on these findings, flow sheets for recovering nickel from the spent baths are proposed.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.10
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• pp.940-948
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• 2007

The Advanced Spent Fuel Conditioning Process(ACP), which is the process of the reduction of uranium oxide by lithium metal in a high temperature molten salt bath for spent fuel, was developed at Korea Atomic Energy Research Institute (KAERI). Since the ACP equipment is located in an intense radiation field (hot cell) as well as in a high temperature, it must be remotely operated and maintained. The ACP hot cell is very narrow so the workspace of the wall-mounted mechanical Master-Slave Manipulators(MSMs) is restricted. A Bridge Transported Servo Manipulator(BTSM) system has been developed to overcome the limitation of an access that is a drawback of the mechanical MSMs. The BTSM system consists ot a bridge crane with telescoping tubeset, a slave manipulator, a master manipulator, and a control system. We applied a bilateral position-position control scheme with friction compensation as force-reflecting controller. In this paper, the transmission characteristics on the tendon-and-pulley train is numerically formulated and analyzed. Also, we evaluate the performance of the force-reflecting servo manipulator.

• Resources Recycling
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• v.23 no.6
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• pp.22-29
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• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (100 mg/L), PVP($FeCl_3:PVP$ = 1 : 4, w/w) and Pd($FeCl_3:PdCl_2$ = 1 : 0.001, w/w) were used, iron nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.388-400
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• 2022

This study analyzed the Internet consumption behavior concerning pet care through in-depth interviews with 11 people who take care of pets. In this study, along with owners of domestic companion animals, stray cat caregivers were included as pet consumers, which have not yet been included in this category in existing research. Internet consumption was found to differ between people with dogs and people with cats. In the case of dog owners, they bought a lot of bath products, clothes harnesses, and strollers that were not appropriate for cats. Although the pet-poor phenomenon is known to occur a lot among young consumers, who care for pets behavior at the cost of money spent on themselves, even stray cat caregivers, mostly middle-aged women, are wary of becoming pet-poor. It cannot be said that there are gender differences in online shopping of pet consumers. In general, women, who did mainly Internet shopping, and if they are not used to using the Internet, their husbands made purchases online instead.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.3
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• pp.61-70
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• 2024

Purpose: The Asan Hot Springs are adjacent to the Seoul Metropolitan area and have excellent traffic access. However, a steady decline in tourist numbers followed the decline in the urban population. This study aims to provide participants with a hot springs visit as part of their independent tourism experience and then analyze their feedback to obtain meaningful suggestions to enhance local tourism. Methods: We recruited 12 families interested in taking a two-day, one-night tour, including a visit to the Asan Hot Springs. Participating families were grouped into two cohorts (Type C and Type A) depending on whether they included children aged one to ten. Each family answered a survey regarding their overall satisfaction with the Asan Hot Springs and provided targeted feedback regarding hot spring resorts, accommodations, restaurants, adjacent tourist spots, and tourism costs. Results: Most of the families that participated in the study were residents of Seoul, Incheon, or Kyunggi (74.47%); the majority were two-generation families (75%) with children (75%). The Type C group enjoyed the campsite (55.56%) accommodations at the Asan Hot Springs more than their Type A counterparts. Families visited an average of 3.6 places during their stay, and 61.11% of participating families visited entertainment and tourist attractions, including the Type C visit to the thermal bath. Compared with Type A, Type C families spent more on tourism and were more satisfied with the entertainment and tourist attractions experience. Overall, all study participants were satisfied with the thermal sources. Conclusion: Our results indicate that families with children have a higher added value than visitor groups consisting only of adults. Considering the significant impact on the local economy, the Asan Hot Springs and associated tourist attractions and services should be developed with these visitors in mind.