• Bulletin of the Korean Chemical Society
• /
• v.9 no.6
• /
• pp.345-349
• /
• 1988

The polycrystalline powder of (CaLa) (MgMo)$O_6$ has been prepared at $1350^{\circ}C$ in $H_2/H_2O$ and $N_2$ flowing atmosphere. The powder X-ray diffraction pattern indicates that (CaLa) (MgMo)$O_6$ has a monoclinic perovskite structure with the lattice constants $a_0=b_0=7.901(1){\AA}$, $c =7.875(1){\AA}\;and\;{\gamma}=89^{\circ}$16'(1'), which can be reduced to orthorhombic unit cell, a = 5.551(1) ${\AA}$, b = 5.622(1) ${\AA}$ and c = 7.875(1) ${\AA}$. The infrared spectrum shows two strong absorption bands with their maxima at 590($ν_3$) and 380($ν_4$) cm, which are attributed to $2T_{1u}$ modes indicating the existence of highly charged molybdenum octahedron $MoO_6$ in the crystal lattice. According to the magnetic susceptibility measurement, the compound follows the Curie-Weiss law below room temperature with the effective magnetic moment 1.83(1)$_{{\mu}B}$, which is well consistent with that of spin only value (1.73 $_{\mu}_B$) for $Mo^{5+}$ with $4d^1$-electronic configuration within the limit of experimental error. From the thermogravimetric analysis, it has been confirmed that (CaLa) (MgMo)$O_6$ decomposes gradually into $CaMoO_4,\;MoO_3,\;MgO,\;La_2O_3$ and unidentified phases due to the oxidation of $Mo^{5+}$ to $Mo^{6+}$.

• The Journal of Korean Philosophical History
• /
• no.50
• /
• pp.139-169
• /
• 2016

Nakron School of the ruling Noron Party in late Joseon Dynasty was at the helm of state with Neo-Confucian ideology and it came out of being obsessed with conventional 'spiritual' aspects and changed both political and academic atmosphere with interests in 'matters.' The power leading such a change was scholars in Seoksil Seowon (石室書院) which centered around Kim Won-Haeng (金元行). However, except for few progressive scholars-Bukhak scholars (北學論者), most of Nakron scholars secretly acknowledged the actuality of Qing Dynasty but they failed to get out of old Neo-Confucian traditions. It was difficult for them to accept Bukhak theory which jeopardized the existence of administration. They sought plans both to keep Neo-Confucian traditions and Sinocentrism in Joseon and to reach the cultural level of Qing Dynasty and in that process, they recognized restoration of the statecraft study (經世學) summarized on Seongridaejeon as an alternative. Hwang Yun-Seok is a representative Neo-Confucian scholar in such response of Nakron. He rediscovered value of the science of xiangshu in the Neo-Confucian category and highlighted importance of Seongridaejeon yet again.

• Advances in environmental research
• /
• v.9 no.4
• /
• pp.275-284
• /
• 2020

We provide the first study on the occurrence of microplastics in Dal lake, Kashmir, India. Microplastics act as catastrophe that trigger many environmental problems. The key origins of microplastics are larger plastics, which split into smaller plastics after UV light disintegration. There is relatively little work carried out on the existence of microplastics. The present work has been undertaken on the occurrence of microplastics at four pre-selected sites (surface water) in Dal lake, Kashmir. The samples were taken to the laboratory to dissolve organic matter by using H2O2 (6%). To speed up the organic digestion; the treated mixture was heated on a hot plate at 70℃. The mixture was then subjected to density separation. The supernatant obtained was observed under the microscope (10X) and measurements were taken. At site-I, the microplastics ranged from 2-3 mm, site-II 5-6 mm, site-III 3-4 mm, site-IV 4-5 mm in thickness, indicating the presence of microplastics in the lake. The presence of microplastics indicated that the lake has undergone an anthropogenic change over a period of time. Our research highlights the value of enhancing the quality of the drainage system and sewage disposal. This work can be helpful to recognize successful microplastic control management techniques and possible threats associated with the Dal lake. So far, no such data on the presence of microplastics in Kashmir lakes is available.

• Journal of the Institute of Convergence Signal Processing
• /
• v.22 no.2
• /
• pp.79-84
• /
• 2021

The most important device of the AGV is the guide sensor, and the typical function of this sensor is high accuracy and extraction of the road. If the accuracy of the guide sensor is low or the sensor device is extracted the wrong track, this causes the problems such as the AGV collision, track-out, the load falling due to AGV swing. In order to improve these problems, this study is proposed a signal processing method of the guide sensor based on multi-maskings and the center of gravity method, and evaluated its performance. As a result, the proposed method showed that the mean error of absolute value is 2.32[mm] and it showed performance improvement of 27[%] than the center of gravity method of existence. Therefore, when the proposed signal processing method is applied, It is thought that the posture control and driving stability of the AGV will be improved.

• CELLMED
• /
• v.11 no.3
• /
• pp.16.1-16.7
• /
• 2021

Cancer is an abnormal growth of cells in body which leads to death. These cells are born due to imbalance in cell proliferation mechanism. In 2018, WHO released new statistics on cancer incidence, mortality, and prevalence worldwide i.e., GLOBOCAN 2018 estimates for 28 types of cancer in which more prevalence of cervix and breast cancer. According to survey, in India about 7.8 million cancer deaths and 11.5 million new cases arise in 2018, which will increase to 19.3 million new cases per year by 2025. Though breast cancer as such is not explained anywhere in Ayurvedic compendia, correlations can be done with the Stana Arbuda. Ayurveda, the ancient system of medicine came into existence 1000's of years ago with an objective of maintaining the health of people and treating diseases. Many herbs used in Ayurveda have been screened for activity against cancer and in-vitro and in-vivo studies have given promising leads. The plant, called as "Mother of Medicine", Haritaki has been extensively studied for its various ailments because of its extraordinary healing potency. Haritaki (Terminalia chebula Retz.), Family: Combretaceae have a great therapeutic value and is widely distributed in India. Dried fruit of Terminalia chebula contains high quantities phenolic compounds consist of ellagic acid, gallic acid and chebulic acid. The fruit extract of T. chebula is having different biological properties like anticancer, antioxidant, hepatic and renal protective activities etc. In this study, we focus on the use of CO₂ extract of Terminalia chebula, on the breast cancer cell line MDA-MB-231. All tests proved that CO₂ extract of Terminalia chebula containing active chemical component, therefore our experiment showed the positive results for CO₂ extract of Terminalia chebula against breast cancer cell line cancer MDA-MB-231. The MTT assay results were used to evaluate the anti-cancer activity of the extract. The percentage of cell growth and cell viability were calculated from tabulated result values of MTT assay. Cell viability MTT assay also showed significant growth inhibition, at the same time statistical analysis of MTT assay also proved significant results.

• Journal of Electrochemical Science and Technology
• /
• v.13 no.2
• /
• pp.237-253
• /
• 2022

The methyl 2-(1,3-dithietan -2- ylidene)-3-oxobutanoate (MDYO) and 2-(1,3-dithietan-2-ylidene) cyclohexane -1,3-dione (DYCD) were synthesized and tested at various concentrations as corrosion inhibitors for 316L stainless steel in 1 M HCl using weight loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), surface analysis techniques (SEM / EDX and Raman spectroscopy) and Functional Density Theory (DFT) was also used to calculate quantum parameters. The obtained results indicated that the inhibition efficiency of MDYO and DYCD increases with their concentration, and the highest value of corrosion inhibition efficiency was determined in the range of concentrations investigated (0.01 × 10^-3 - 10^-3 M). Polarization curves (Tafel extrapolation) showed that both compounds act as mixed-type inhibitors in 1M HCl solutions. Electrochemical impedance spectra (Nyquist plots) are characterized by a capacitive loop observed at high frequencies, and another small inductive loop near low frequencies. The thermodynamic data of adsorption of the two compounds on the stainless steel surface and the activation energies were determined and then discussed. Analysis of experimental results shows that MDYO and DYCD inhibitors adsorb to the metal surface according to the Langmuir model and the mechanism of adsorption of both inhibitors involves physisorption. SEM-EDX results confirm the existence of an inhibitor protective film on the stainless steel surface. The results derived from theoretical calculations supported the experimental observation.

• Journal of Korea Trade
• /
• v.27 no.1
• /
• pp.79-100
• /
• 2023

Purpose - The purpose of this study is to analyze the market power of the Korea Container Shipping Market (Intra Asia, Korea-Europe, and Korea-U.S.) to verify the existence of collusion empirically, and to answer whether the joint actions of liner market participants in Korea have formed market dominance for each route. Precisely, it will be verified through the Lerner index as to whether the regional market of Asia is a monopoly, oligopoly, or perfect competition. Design/methodology - This study used a Lerner index adjusted with elasticity presented in the New Imperial Organization (NEIO) studies. NEIO refers to a series of empirical studies that estimate parameters to judge market power from industrial data. This study uses B-L empirical models by Bresnahan (1982) and Lau (1982). In addition, NEIO research data statistically contain self-regression and stability problems as price and time series data. A dynamic model following Steen and Salvanes' Error Correction Model was used to solve this problem. Findings - The empirical results are as follows. First, λ, representing market power, is nearly zero in all three markets. Second, the Korean shipping market shows low demand elasticity on average. Nevertheless, the markup is low, a characteristic that is difficult to see in other industries. Third, the Korean shipping market generally remains close to perfect competition from 2014 to 2022, but extreme market power appears in a specific period, such as COVID-19. Fourth, there was no market power in the Intra Asia market from 2008 to 2014. Originality/value - Doubts about perfect competition in the liner market continued, but there were few empirical cases. This paper confirmed that the Korea liner market is a perfect competition market. This paper is the first to implement dynamics using ECM and recursive regression to demonstrate market power in the Korean liner market by dividing the shipping market into Deep Sea and Intra Asia separately. It is also the first to prove the most controversial problems in the current shipping industry numerically and academically.

• Journal of the Korean Society for Library and Information Science
• /
• v.57 no.2
• /
• pp.241-269
• /
• 2023

This study developed a scale for measuring publicness and examined the differences in perception of publicness according to library usage experience, personal characteristics of local residents, and types of library services. The survey was conducted on 15 local public libraries in 5 districts of Seoul, targeting library users and local residents. As a result, it was found that the publicness of libraries is composed of three factors: participatory responsiveness, procedural fairness, and situational equality, which demonstrate different aspects formed through the interaction between library users and local residents in the local community. The study derived ways to enhance publicness and presented in detail which aspect of publicness needs to be enhanced according to library usage experience and service period, local residents' occupational environment and experience of local activities, and types of library services. The study suggests that when service experiences that enhance publicness are effectively provided, more local residents can benefit from them, and the value of the library's existence can be demonstrated.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.2
• /
• pp.232-237
• /
• 2008

A method to generate electric power from small scale water tank. For this purpose, manufacturing tank is investigated, measuring water level change at any time, and finally comparing experimental and theoretical value, are performed. Inner and outer tank are made to simulate flood and ebb generation. Two sets of pipe are connected between tanks, and experiments are performed under varying flowrate. Coefficients of flowrate are calculated comparing water level change data and theoretical value. Measured and theoretical water levels are highly correlated, and this ascertains that analytical equation simulates real water level changes well. Flowrate change depending on the existence of propeller and valve, on flood and ebb generation, shows the necessity of experiments in the process of manufacturing electric power system. Moreover, total energy calculated from experimental data agrees well with that of theoretical equation. In spite of small tidal power output, this generating system with optimum water tank can be applied to any place where high water level change occurs, and can make a contribution to producing new and renewable energy consequently.

• Journal of Periodontal and Implant Science
• /
• v.43 no.1
• /
• pp.41-46
• /
• 2013

Purpose: The objective of this study was to evaluate the effect of microthreads on removal torque and bone-to-implant contact (BIC). Methods: Twelve miniature pigs for each experiment, a total of 24 animals, were used. In the removal torque analysis, each animal received 2 types of implants in each tibia, which were treated with sandblasting and acid etching but with or without microthreads at the marginal portion. The animals were sacrificed after 4, 8, or 12 weeks of healing. Each subgroup consisted of 4 animals, and the tibias were extracted and removal torque was measured. In the BIC analysis, each animal received 3 types of implants. Two types of implants were used for the removal torque test and another type of implant served as the control. The BIC experiment was conducted in the mandible of the animals. The $P_1-M_1$ teeth were extracted, and after a 4-month healing period, 3 each of the 2 types of implants were placed, with one type on each side of the mandible, for a total of 6 implants per animal. The animals were sacrificed after a 2-, 4-, or 8-week healing period. Each subgroup consisted of 4 animals. The mandibles were extracted, specimens were processed, and BIC was analyzed. Results: No significant difference in removal torque value or BIC was found between implants with and without microthreads. The removal torque value increased between 4 and 8 weeks of healing for both types of implants, but there was no significant difference between 8 and 12 weeks. The percentage of BIC increased between 2 and 4 weeks for all types of implants, but there was no significant difference between 4 and 8 weeks. Conclusions: The existence of microthreads was not a significant factor in mechanical and histological stability.