• Journal of Electrochemical Science and Technology
• /
• v.10 no.2
• /
• pp.159-169
• /
• 2019

The activated carbon materials were prepared from waste biomass by ultrasonic assisted chemical activation method (UCA), ultrasonic assisted physical activation method (UPA) and Manganese nitrogen doped carbon (Mn/N-C). The XRD result shows the turbostatic (fully disordered) structure. The cyclic voltammetry test was done at 50 mV/s using 1M sodium sulfate and the values of specific capacitance were found to be 93, 100 and 115 F/g for UCA, UPA and Mn/N-C respectively. The power density values for the samples UCA, UPA and Mn/N-C were found to be 46.04, 87.97 and 131.42 W/kg respectively. The electrochemical impedance spectroscopy was done at low frequency between 1 to 10 kHz. The Nyquist plot gives the resistant characteristics of the materials due to diffusional resistance at the electrode-electrolyte interface. The Energy Dispersive X-Ray Spectroscopyanalysis (EDAX) analysis showed that the percentage doping of nitrogen and manganese were 3.53 wt% and 9.44 wt% respectively. It is observed from the experiment Mn/N-C doped carbon show good physical and electrochemical properties.

• Journal of the Korean Society for Heat Treatment
• /
• v.32 no.3
• /
• pp.124-130
• /
• 2019

Friction stir welding is one of the interesting welding methods for titanium and its alloy which proceeds with plastic flow due to thermo-mechanical stirring and friction heat. Solid-state welding can solve severe problems such as high-temperature oxidation, interstitial oxygen diffusion and grain coarsening by liquid-state welding. Dynamic recrystallization and grain refinement can vary significantly with the plunging load and rotational speed of tool during friction stir welding, and suitable process conditions must be optimized to obtain microstructure and better mechanical characteristics. Suitable FSW conditions were 1000 kg of plunging load and 200 rpm of rotational speed and it showed YS 270 MPa, UTS 332.1 MPa, and El 17.3%, which were very similar to those of wrought titanium sheet.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.35 no.10
• /
• pp.31-39
• /
• 2019

This research analyzes the involvement of hermeneutics in architectural history and theory studies and its pedagogy in the West after the 1950s. The research focuses on representative architectural schools in the West. In particular, this paper examines from the curricula of Joseph Rykwert and Dalibor Vesely at the University of Essex to their former students who played a significant role in expanding the history and theory courses in the late 20th century in the North America such as Alberto $P{\acute{e}}rez-G{\acute{o}}mez^{\prime}s$ (McGill University) and David Leatherbarrow (University of Pennsylvania). Through their leadership and other related architectural historians' efforts: 1) hermeneutics have been applied in architectural history studies from the critical perspectives of post-modern philosophy; 2) hermeneutics help stimulate discussions of thoughtful architectural design, enabling strong interactions between design theories and the embodied meanings of buildings; 3) these schools have produced and involved many prominent scholars who actively practice and develop the discourse of architectural history and theory from the perspectives of hermeneutics; 4) Finally, the hermeneutic approach in architectural history studies has enlightened many achieved architects' thoughtful design practice and theories within the emerging context of regional criticism and international cross-cultural architecture.

• Asia pacific journal of information systems
• /
• v.29 no.1
• /
• pp.117-143
• /
• 2019

Advances in information technology (IT) bring about technological innovation in financial businesses, referred to as financial technology (fintech), beyond the traditional financial industry. While fintech implies more convenient and various financial services to customers, it leads to more complexity in the financial sector, as different industry players (e.g., IT firms) can participate in financial businesses. The complexity of fintech causes controversial issues related to policies and the appropriate development direction. In order to provide insight into the current state of fintech, this study explores the fundamental understanding of the fintech phenomenon from the perspective of the major stakeholders (i.e., financial authorities, financial companies, IT firms) in South Korea. This study analyzed news articles, where those stakeholders expressed their arguments, by using a content analysis. The study also conducted an intensive examination of their arguments by using a core-periphery approach of social representations. This study found that while the three beholders had a common opinion on deregulation of the fintech industry, each of them had different knowledge of the phenomenon. By revealing each beholder's structure of representations of fintech, this study not only provides common knowledge regarding fintech but also explicates the perceptual gaps among stakeholders. Findings of the study offer a big picture of current fintech initiatives, which can be useful knowledge for future research on fintech.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.5
• /
• pp.247-262
• /
• 2019

This study involved the effects of home-visit program with cognitive-stimulating activities on cognitive function and memory self-efficacy of an elderly with dementia special rating(5rates). The study was conducted from February 11 to April 26, 2019 using a 65-year old woman residing in G Metropolitan City. The individual subject study used an A-B-A design. The subject performed activities that required thinking and resolving in order to stimulate both her body and cognition. The activities chosen were easily accessible to those having a form of mild dementia, rates 5 dementia special rating, and repetitively stimulated the subject's intellectual capacity in an attempt to increase her degraded cognitive functioning. Specifically, the activities exercised both short-term memory and recollection using familiar letters, numbers, and bodily movements frequently encountered in daily life. The program positively affected the subject's memory and concentration. In addition, the program was found to be feasible for home use by those with mild dementia, obviating the need to travel to a location like a welfare center. The author presents specific activities for stimulating cognition that can effectively intervene to positively influence the cognitive functioning and memory of those with rates 5 dementia special rating.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.22 no.2
• /
• pp.121-132
• /
• 2019

Recently as development of internet, Service based on World Wide Web is rapidly growing. According to this, Importance for suitability of web service is emphasized by increased user with development of technique of web service. Geospatial information field included with River Geospatial information(HydroG-OneFlow) has been doing that many study about web service which center of IT, However study about test of web service is lacking of situation. Accordingly, verification should be carried out to determine the performance of Web services with the Web services implementation HydroG-OneFlow. Performance & stability test are verified that HydroG-OneFlow for Apache Jmeter of open source and conformability & interoperability test are verified for StyleCop. Result of performance is that if users are increase the number of 500, average responses time is about two seconds. and Result of reliability is that if users are increase the number of 500, decrease about 0.2%. it is verified that conformability and interoperability test to swelled about reliability of HydroG-OneFlow. Through that It will be compensate for the implementation of seb service and vulnerability of HydroG-OneFlow.

• Journal of Life Science
• /
• v.29 no.9
• /
• pp.964-971
• /
• 2019

Hepatic lipid accumulation and insulin resistance increases in patients with non-alcoholic fatty liver disease. Piperine is a major compound found in black pepper (Piper nigrum) and long pepper (P. longum). Piperine has been used in fine chemical for its anti-cancer, anti-obesity, anti-diabetic, anti-inflammatory and anti-oxidant properties. However, the signaling-based mechanism of piperine and its role as an inhibitor of lipogenesis and insulin resistance in human hepatocyte cells remains ill-defined. In the present study, we explored the effects of piperine on lipid accumulation and insulin resistance, and explored the potential underlying molecular mechanisms in palmitate-treated HepG2 cells. Piperine treatment resulted in a significant reduction of triglyceride content. Furthermore, piperine treatment decreased palmitate-treated intracellular lipid deposition by inhibiting the lipogenic target genes, sterol-regulatory-element-binding protein 1c (SREBP-1c) and fatty acid synthase (FAS); whereas the expression of carnitine palmitoyl transferase (CPT-1) and phosphorylation of acetyl coenzyme A carboxylase (ACC) gene involved in fatty acid oxidation was increased. Moreover, piperine also inhibited the phosphorylation of insulin receptor substrate (IRS)-1 (Ser307). Piperine treatment modulated palmitate-treated lipid accumulation and insulin resistance in HepG2 cells with concomitant reduction of lipogenic target genes, such as SREBP-1 and FAS, and induction of CPT-1-ACC and phosphorylation of IRS-1 (Tyr632)-Akt pathways. Therefore, piperine represents a promising treatment for the prevention of lipid accumulation and insulin resistance.

• Safety and Health at Work
• /
• v.10 no.3
• /
• pp.377-383
• /
• 2019

Objectives: Exposure to fine particles in urban air has been associated with a number of negative health effects. High levels of fine particles have been detected at underground stations in big cities. We investigated the exposure conditions in four occupational groups in the Stockholm underground train system to identify high-exposed groups and study variations in exposure. Methods: $PM_1$ and $PM_{2.5}$ were measured during three full work shifts on 44 underground workers. Fluctuations in exposure were monitored by a real-time particle monitoring instrument, pDR, DataRAM. Qualitative analysis of particle content was performed using inductively coupled plasma mass spectrometry. Nitrogen dioxide was measured using passive monitors. Results: For all underground workers, the geometric mean (GM) of $PM_1$ was $18{\mu}g/m^3$ and of $PM_{2.5}$ was $37{\mu}g/m^3$. The particle exposure was highest for cleaners/platform workers, and the GM of $PM_1$ was $31.6{\mu}g/m^3$ [geometric standard deviation (GSD), 1.6] and of $PM_{2.5}$ was $76.5{\mu}g/m^3$ (GSD, 1.3); the particle exposure was lowest for ticket sellers, and the GM of $PM_1$ was $4.9{\mu}g/m^3$ (GSD, 2.1) and of $PM_{2.5}$ was $9.3{\mu}g/m^3$ (GSD, 1.5). The $PM_1$ and $PM_{2.5}$ levels were five times higher in the underground system than at the street level, and the particles in the underground had high iron content. The train driver's nitrogen dioxide exposure level was $64.1{\mu}g/m^3$ (GSD, 1.5). Conclusions: Cleaners and other platform workers were statistically significantly more exposed to particles than train drivers or ticket sellers. Particle concentrations ($PM_{2.5}$) in the Stockholm underground system were within the same range as in the New York underground system but were much lower than in several older underground systems around the world.

• Journal of Advanced Navigation Technology
• /
• v.23 no.2
• /
• pp.151-157
• /
• 2019

In geostationary satellite communications, which are widely used for broadcasting and communication, there is a path loss where the signal power on the path is largely reduced. It is important to consider rain attenuation when calculating link budget because the Ka band frequency is vulnerable to rain attenuation. In this study, rainfall trends were analyzed by using rainfall data from the year 2000 in four regions of Korea (Seoul, Incheon, Busan, Jeju) and the rainfall attenuation was calculated. This was used to analyse the satellite link budget and receiving performance for the down-link of the korea satellite COMS. In this study, the calculated G/T for the rainfall intensity of 0.5% per year using the rainfall data for 18 years increased by approximately $8.5dBK^{-1}$ compared to the ITU's zone-K rain model, and decreased by approximately $1dBK^{-1}$ compared to the precipitation data for 13 years from the TTA(Korea Telecommunications Technology Association). The results of this study can be used for the design of G/T in domestic-installed satellite ground station.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.45 no.3
• /
• pp.217-224
• /
• 2019

Phthalates, endocrine disrupting chemicals, are similar in structure to sex hormones and mainly show reproductive toxicity and developmental toxicity. In this study, we analyzed 11 phthalates, including 3 kinds of phthalates prohibited in cosmetic use and 8 kinds of phthalates regulated in 'Common standards for children's products safety' and EU cosmetic regulation (EC No. 1223/2009). The phthalate analysis was optimized using GC-MS/MS. In analytical method validation, this method was satisfied in specificity, linearity, recovery rate, accuracy and MQL. Therefore, we used this method to analyze 82 products of Nail cosmetics & polish. Although six phthalates such as DBP, BBP, DEHP, DPP, DIBP and DIDP were detected at concentrations of $1.0{\sim}59.8{\mu}g/g$g, they were suitable to Korean cosmetic standards. DIBP and DBP were detected at concentration of $1.1{\sim}2.6{\mu}g/g$ in artificial nail, DBP and DEHP were $1.4{\sim}2.5{\mu}g/g$ in glue for nails, and DIBP, DBP, and DEHP were $2.5{\sim}33.3{\mu}g/g$ in nail stickers. Although substances such as DBP and DEHP in artificial nail, Glue for nails, and nail stickers were detected, they were suitable to 'Common safety standards for children's products. DIBP is not a regulated substance in Korea but showed the third highest detection rate following DBP (84.6%) and DEHP (63.4%). The concentration of phthalates detected in nail products is considered to be safe in current standards but continuous monitoring and research about non-regulated substances are also needed to be considered.