Poor mechanical properties and bacterial infection are the main problems faced by dental restorative resins in clinical use. In this study, graphene quantum dots (GQDs) grafted with imidazole groups and mesoporous silica (MSN) are co-filled in a dental resin to impart excellent antimicrobial activity and mechanical properties to the dental resin. The higher specific surface area of GQDs and MSN results in an increased contact area with the resin matrix, which enhances the strength of the dental composite resin. The introduction of GQDs significantly improves the antimicrobial activity of the resin. The inhibition efficiency of the composite resin against Streptococcus mutans reached 99.9% with the addition of GQDs at only 0.2 wt.%. When MSN and GQDs are co-filled, MSN interferes with the release of GQDs, thus reducing the antimicrobial activity of the dental resin but improving the cyto-compatibility. By reasonably adjusting the amount of GQDs and MSN, the dental composite resin can exhibit excellent antimicrobial properties, mechanical properties and cyto-compatibility at the same time.

As part of the safety case development for generic disposal sites in Korea, it is necessary to develop generic assessment models using various geosphere–biosphere interfaces (GBIs) and potentially exposed groups (PEGs) that reflect the natural environmental characteristics and the lifestyles of people in Korea. In this study, a unique modeling strategy was developed to systematically construct and select Korean generic biosphere assessment models. The strategy includes three process steps (combination, screening, and experts’ scoring) for the biosphere system conditions. First, various conditions, such as climate, topography, GBIs, and PEGs, were combined in the biosphere system. Second, the combined calculation cases were configured into interrelation matrices to screen out some calculation cases that were highly unlikely or less significant in terms of the exposure dose. Finally, the selected calculation cases were prioritized based on expert judgment by scoring the knowledge, probability, and importance. The results of this study can be implemented in the development of biosphere assessment models for Korean generic sites. It is believed that this systematic methodology for selecting the candidate calculation cases can contribute to increasing the confidence of future site-specific biosphere assessment models.

This research examines the effect of adding aluminum on the structural, phasic, and magnetic properties of CoCrFe NiMnAlx high-entropy alloys. To this aim, the arc-melt process was used under an argon atmosphere for preparing cast samples. The phasic, structural, and magnetic properties of the samples were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrational magnetometry (VSM) analyses. Based on the results, the addition of aluminum to the compound caused changes in the crystalline structure, from FCC solid solution in the CoCrFeNiMn sample to CoCrFeNiMnAl BBC solid solution. It was associated with changes in the magnetic property of CoCrFeNiMnAlx high-entropy alloys, from paramagnetic to ferromagnetic. The maximum saturation magnetization for the CoCrFeNiMnAl casting sample was estimated to be around 79 emu/g. Despite the phase stability of the FCC solid solution with temperature, the solid solution phase formed in the CrCrFeNiMnAl high-entropy compound was not stable, and changed into FCC solid solution with temperature elevation, causing a reduction in saturation magnetization to about 7 emu/g.

The records system is believed to have started in Italy in the 14th century in line with trade developments in Europe. In 1491, Luca Pacioli, a mathematician, and an Italian Franciscan monk wrote the first book that described double-entry accounting processes. In many countries, including Korea, the government accounting standards used single-entry bookkeeping rather than double-entry bookkeeping that can be aggregated by account subject. The cash-based and single-entry bookkeeping used by the government in the past had limitations in providing clear information on financial status and establishing a performance-oriented financial management system. Accordingly, the National Accounting Act (promulgated in October 2007) stipulated the introduction of double-entry bookkeeping and accrual accounting systems in the government sector from January 1, 2009. Furthermore, the Korean government has also introduced International Financial Reporting Standards (IFRS), and the System of National Accounts (SNA). Since 2014, Korea owned five national accounts. In Korea, valuation began with the 1968 National Wealth Statistics Survey. The academic origins of the valuation of national wealth statistics which had been investigated by due diligence every 10 years since 1968 are based on the 'Engineering Valuation' of professor Marston in the Department of Industrial Engineering at Iowa State University in the 1930s. This field has spread to economics, etc. In economics, it became the basis of capital stock estimation for positive economics such as econometrics. The valuation by the National Wealth Statistics Survey contributed greatly to converting the book value of accounting data into vintage data. And in 2000 National Statistical Office collected actual disposal data for the 1-digit asset class and obtained the ASL(average service life) by Iowa curve. Then, with the data on fixed capital formation centered on the National B/S Team of the Bank of Korea, the national wealth statistics were prepared by the Permanent Inventory Method(PIM). The asset classification was also classified into 59 types, including 2 types of residential buildings, 4 types of non-residential buildings, 14 types of structures, 9 types of transportation equipment, 28 types of machinery, and 2 types of intangible fixed assets. Tables of useful lives of tangible fixed assets published by the Korea Appraisal Board in 1999 and 2013 were made by the Iowa curve method. In Korea, the Iowa curve method has been adopted as a method of ASL estimation. There are three types of the Iowa curve method. The retirement rate method of the three types is the best because it is based on the collection and compilation of the data of all properties in service during a period of recent years, both properties retired and that are still in service. We hope the retirement rate method instead of the individual unit method is used in the estimation of ASL. Recently Korean government’s accounting system has been developed. When revenue expenditure and capital expenditure were mixed in the past single-entry bookkeeping we would like to suggest that BOK and National Statistical Office have accumulated knowledge of a rational difference between revenue expenditure and capital expenditure. In particular, it is important when it is estimated capital stock by PIM. Korea also needs an empirical study on economic depreciation like Hulten & Wykoff Catalog A of the US BEA.

Exposure to ultraviolet (UV) light is often associated with skin damage, sometimes very serious, and in recent times has received particular attention as a health risk. As a result, the proper use of sunscreen has long been recommended to protect against skin damage. The continued increase in the use of sunscreen may be linked to increased information about the risk of melanoma and non-melanoma skin cancer caused by prolonged exposure to ultraviolet rays. Natural and harmless materials that block and prevent UV light have emerged as essential household items in the field of skin beauty. New materials need to be considered and evaluated in relation to ultraviolet rays and their harmful effects. This study aims to explain the effect of UV exposure on human skin, the classification of sunscreens, the application of zeolite, nano clay, and LDH in sunscreen formulations, as well as the regulation of this service in various countries around the world.

ASL estimation of public building is based on how appropriate the maximum age of the asset is derived based on the age record of the asset in the statistical data owned by public institutions. This is because we get a 'constrained' ASL by that number. And it is especially true because other studies have assumed that the building is an Iowa curve R3. Also, in this study, the survival rate is 1% as the threshold value at which the survival curve and the predictable life curve almost coincide. Rather than a theoretical basis, in the national statistical survey, the value of residual assets was recognized from the net value of 10% of the acquisition value when the average service life has elapsed, and 1% when doubling the average service life has elapsed. It is based on the setting mentioned above. The biggest constraint in fitting statistical data to the Iowa curve is that the maximum ASL is selected at R3 150%, and the 'constrained' ASL is calculated by the proportional expression on the assumption that the Iowa curve is followed. In like manner constraints were considered. First, the R3 disposal curve for the RCC(reinforced cement concrete) building was prepared according to the discarding method in the 2000 work, and it was jointly worked on with the National Statistical Office to secure the maximum amount of vintage data, but the lacking of sample size must be acknowledged. Even after that, the National Statistical Office and the Bank of Korea have been working on estimating the Iowa curve for each asset class in the I-O table. Another limitation is that the asset classification uses the broad classification of buildings as a subcategory. Second, if there were such assets with a lifespan of 115 years that were acquired in 1905 and disposed of in 2020, these discarded data would be omitted from this ASL calculation. Third, it is difficult to estimate the correct Iowa curve based on the stub-curve even if there is disposal data because Korea has a relatively shorter construction history, accumulated economic wealth since the 1980’s. In other words, “constrained” ASL is an under-estimation of its ASL. Considering the fact that Korea was an economically developing country in the past and during rapid economic development, environmental factors such as asset accumulation and economic ability should be considered. Korea has a short period of accumulation of economic wealth, and the history of 'proper' architectures faithful to building regulations and principles is short and as a result, buildings 'not built properly' and 'proper' architectures are mixed. In this study, ASL of RCC public building was estimated at 70 years.

In an automotive plant, an automated storage and retrieval system (ASRS) synchronizes material handling flows from a part production line to an auto-assembly line. The part production line transfers parts on small-/large-sized pallets. The products on pallets are temporarily stored on the ASRS, and the ASRS retrieves the products upon request from the auto-assembly line. Each ASRS aisle is equipped with narrow-/wide-width racks for two pallet sizes. An ASRS aisle with narrow-/wide-width racks improves both storage space utilization and crane utilization while requiring delicate ASRS aisle design, i.e., the locations of the narrow-/wide-width racks in an ASRS aisle, and proper operation policies affect the ASRS performance over demand fluctuations. We focus on operation policies involving a common storage zone using wide-width racks for two pallet sizes and a storage-retrieval job-change for a crane based on assembly-line batch size. We model a discrete-event simulation model and conduct extensive experiments to evaluate operation policies. The simulation results address the best ASRS aisle design and suggest the most effective operation policies for the aisle design.

With rapid urbanization, the importance of urban warfare is increasing, and it is also required to reflect the characteristics of cities in wargame models. However, in the military's wargame models, the urbanization factor was calculated and used without theoretical basis. In this study, we investigate techniques for estimating the urbanization factor using Fractal dimension theory. The urbanization factor we propose can suggest a logical and valid representative value when used in conjunction with Agent Based Model and other methodologies.

In recent years, there is rising conversation about animal welfare with increasing concern about animals. However, disease control is still not being carried out effectively. It is hard to discuss the specific plan of the domestic animal shelter and pet shop due to limited information about their present condition. Thus, we analyzed existing data and suggested a new disease control system. Disease management reports of pet shops and animal shelters investigated by local government and animal protection organizations were the main reference of this study. As the euthanasia rate of shelters has recently decreased, animals stay in shelters for extended periods. As a result, mortality rate from disease has increased. Also, many animals in pet shops die due to health problems. In animal shelters, there is always a certain proportion of individuals with disease, and many shelters do not treat them or vaccinate animals before infection. In pet shops, information such as each individual’s health condition and vaccination records is not properly disclosed, and contagious pathogens are detected in hygiene tests. In order to improve the condition, each animals’ information should be dealt with using a system based on ICT technology. Also, it is necessary to perform antibody tests and infectious disease kit tests provided by local governments, set up breeding environment manuals, and supervise the management of local governments.

Research and interest in sustainable printing are increasing in the packaging printing industry. Currently, predicting the amount of ink required for each work is based on the experience and intuition of field workers. Suppose the amount of ink produced is more than necessary. In this case, the rest of the ink cannot be reused and is discarded, adversely affecting the company's productivity and environment. Nowadays, machine learning models can be used to figure out this problem. This study compares the ink usage prediction machine learning models. A simple linear regression model, Multiple Regression Analysis, cannot reflect the nonlinear relationship between the variables required for packaging printing, so there is a limit to accurately predicting the amount of ink needed. This study has established various prediction models which are based on CART (Classification and Regression Tree), such as Decision Tree, Random Forest, Gradient Boosting Machine, and XGBoost. The accuracy of the models is determined by the K-fold cross-validation. Error metrics such as root mean squared error, mean absolute error, and R-squared are employed to evaluate estimation models' correctness. Among these models, XGBoost model has the highest prediction accuracy and can reduce 2134 (g) of wasted ink for each work. Thus, this study motivates machine learning's potential to help advance productivity and protect the environment.

This study examined the subacute oral toxicity of Dendropanax morbiferus H.Lév leaves hot-water extracts (DMWE) using male and female Spargue-Dawley rats. Rats were orally administered the DMWE at dose levels of 0, 250, 500, 1,000, and 2,000 mg/kg body weight (BW) for four weeks. For experimental period, clinical signs and the number of deaths were examined, and feed intake and BW of all experimental animals were measured once a week for four weeks. At the end of the experiment, blood samples were collected from all rats, and all animals were euthanized and autopsies were performed to collect major organs. No dead animals were found during the experimental period. In addition, no differences were found between control and DMWE-treated groups in feed intakes, BW changes, organ weights, clinical signs, hematological parameters, and serum biochemical parameters. The results of this study provided evidence that oral administration of DMWE at the dose of 2,000 mg/kg BW is safe in rats and may not exert severe toxic effects.

목적 : 해마다 고령인구는 급격히 증가하고 있어 연령 증가에 따른 백내장 환자도 증가하고 있다. 대부분의 백 내장 수술은 원거리 중심으로 근거리에 대한 부분은 많은 정보가 없다. 다초점 인공수정체를 사용한 수술의 경우 시력 흐림등의 부작용이 존재하고 있어 백내장 수술 후 근거리 가입도에 대한 효과적인 처방이 필요한 실정이다. 방법 : 백내장 수술 전 ․후의 성인 21명 총 42안을 대상으로 굴절이상도, 교정시력, 가입도, 입체시력 등을 측 정하였다. 백내장 수술 후 굴절력이 안정되는 3달 후 검사를 진행하였다. 성별 및 굴절도에 따라 가입도 변화를 분석하였다. 결과 : 백내장 수술 후의 교정시력, 입체시력 및 가입도 모두 유의미하게 상승하였다. 남성이 여성보다 가입도 변화가 적은 것을 확인하였고 원시안에서 근시안보다 가입도 변화가 크게 나타나는 것을 확인하였다. 결론 : 백내장 수술 후에는 위조절에 의해 이론적인 가입도보다 낮은 가입도가 측정된다. 위조절이 나타나는 다양한 인자들을 고려하여 가입도 처방을 한다면 보다 나은 시생활을 영위할 수 있을 것으로 판단된다.

본 연구는 코팅 방법을 활용한 단결정 양극 소재 연구로서 Ni-rich계 다결정 양극 소재로 부터 단결정 양극 소재를 합 성하여 사이클 구동 시 양극 소재의 안정성을 향상시키고자 한다. 양극 소재에 LixCoO2와 LixSnO3 를 각각 코팅하여 이차입자 내부 혹은 외부에 코팅층이 형성된 양극 소재를 합성한 후 이를 소결하여 단결정 형성에 대한 영향을 비교 하였다. 입자 외부에 LixSnO3가 코팅되어 열처리 된 Ni0.8Co0.1Mn0.1O2(NCM811)의 경우 코팅 처리 없이 열처리된 양극 소재 보다 개선된 수명특성을 보였으나, 단결정화가 이뤄지지 않았다. 입자 내부에 LixCoO2 코팅층이 형성된 NCM811 을 열처리 한 결과 이차입자 내부에 형성된 Co 코팅층이 결정화되어 50회 사이클 후 기준 단결정 양극 소재의 방전용 량인 117.34 mAh·g-1 대비 129.11 mAh·g-1의 높은 방전용량을 나타내었고, 형상제어를 통해 이성적인 단결정화가 이뤄 졌다. 본 연구는 다결정체인 Ni-rich 양극소재의 단결정화에 대한 유요한 통찰력을 제공할 것으로 예상한다.

In this study, the acute toxicity of Dendropanax morbiferus H.Lév leaf hot-water extracts (DMWE) was examined in male and female ICR mice. Mice were orally administered the DMWE at dose levels of 0, 250, 500, 1,000 and 2,000 mg/kg body weight (BW) for single-dose toxicity test. There were no significant differences in change of BW between control and all DMWE treated-groups. In hematological and blood biochemical analysis, none of the parameters were affected by the DMWE. Similarly, there were no significant effects on markers for liver and kidney functions in all DMWE treated-groups. Since there were no adverse effects of the DMWE in single oral toxicity tests, even at the highest doses, it was concluded that the lethal dose 50 (LD50) of DMWE is estimated at > 2,000 mg/kg BW.

Fermentation by Rhizopus spp. has been used as a traditional medicine for treating various inflammatory diseases. Allergic asthma is a chronic respiratory disease that is caused by an exaggerated immune response. This study was conducted to ascertain the anti-inflammatory effects of Rhizopus spp. fermentation extract (RU) on a mouse model of ovalbumin (OVA)-induced asthma. The animals were intraperitoneally injected OVA on day 1 and 7, followed by OVA intranasal inhalation on days 14 to 18. The animals were treated daily with RU (100 and 200 mg/kg) by oral gavage from day 18 to day 23. RU significantly decreased eosinophilia and the production of inflammatory cytokines and OVA specific immunoglobulin E in animals with asthma, along with reducing airway inflammation and mucus secretion in lung tissue. Histological changes in the lungs and levels of inflammatory mediators of allergic airway inflammation were evaluated. The regulatory effects of RU on type 2 helper T (Th2) cell activation were investigated. RU administration attenuated asthmatic changes such as inflammatory cell infiltration and mucus production, decreased the levels of Th2-related cytokines, and reduced Th2 cell activation. Administration of RU effectively reduced allergic responses in asthmatic mice, which is associated with regulating Th2 cell activation and differentiation. These results indicate that RU can attenuate the respiratory symptoms of asthma.

Tuberculosis is a potentially deadly infectious disease caused by the Mycobacterium tuberculosis (M. tuberculosis). Tuberculosis is diagnosed by proving the M. tuberculosis in sputum samples based on the results of acid-resistant staining, culture, and nucleic acid amplification tests. However, there is a report that the detection rate of M. tuberculosis is low in acid-resistant staining using tissue specimens. It has been suspected that the cause is a potential loss of acid resistance by the organic solvents used for tissue specimen preparation. Therefore, this study was pursued to find out if Gram staining and fluorescent staining in addition to acid-resistant staining would be helpful in diagnosing tuberculosis. We used four tissue (lung, small intestine, large intestine, and lymph node) samples with chronic granulomatous inflammation observed in HE staining and positive results in real-time PCR. These detection rates and staining properties were investigated through microscopic examination using the Ziehl-Neelsen, Gram, and Auramin rhodamine staining. In this studies, M. tuberculosis were observed by Ziehl-Neelsen, Gram, and Auramin rhodamine staining in all four samples. In the evaluation of clinical microbiology proficiency testing (CMPT), the Ziehl-Neelsen and Gram staining were the same result, but the Auramin rhodamine staining was relatively low. These data indicated that Gram staining is useful for detecting M. tuberculosis in formalin-fixed tissue specimens. Therefore, if the Ziehl-Neelsen and Gram staining are combined as the M. tuberculosis staining method in tissue specimens, a better direction may be provided for tuberculosis diagnosis.

대부분의 모바일 AR 컨텐츠들은 모바일 디바이스의 기술적 한계로 인해 평면 탐지 후, 그 위에서만 구현되는 제한된 구조를 가지고 있다. 이러한 문제는 제한된 공간이 표현의 범위를 제한하기 때문에 모바일 AR의 확산 에 크게 저해가 될 수 있다. 한편 Unity의 AR Foundation이 제공하는 ‘Meshing’은 실제 오브젝트의 크기와 위 치에 알맞게 메시를 생성해주는데, 이를 활용한다면 모바일 AR 컨텐츠들은 평면에서 벗어나 더 넓은 현실 공 간에 구현될 수 있다. 하지만 ‘Meshing’은 모바일 기기의 센서가 닿지 못하는 부분에는 메시를 생성하지 않기 때문에 별도의 작업 없이 그대로 사용한다면 게임 오브젝트가 빠져나갈 수 있는 구멍이 생길 수 있다. 이 구 멍은 컨텐츠 구현에 있어서 치명적이기에 Hole-Filling 알고리즘을 사용하여 구멍을 메우고자 하는 연구가 있 었다. 하지만 기존 연구에서 사용하는 Hole-Finding 알고리즘은 특정 상황에서 외곽선과 구멍을 제대로 구별해 내지 못하는 문제가 있다. 이 문제는 일부 구멍은 메우지 못하고 외관선끼리 이어버려 컨텐츠에 치명적인 문 제를 야기한다. 본 논문에서는 Meshing이 제공하는 노말 벡터와 경계선들로 계산한 노말 벡터 간의 차이를 이 용해 구멍과 외곽선을 구분하는 방법을 제안한다. 이 방법을 적용한 결과, 이전 연구의 방법보다 좀 더 빠르 면서 구멍과 외곽선을 제대로 구별하는 모습을 확인하였다.

Malaysia’s decision to join and rectify the agreement showed that the country is serious about business, trade liberalisation and its support for a fair and transparent trade regime. Moreover, Malaysia is expected to earn approximately USD 200 million in exports, while RCEP will provide immense opportunities for trade and investments, enhanced connectivity, and deepening regional economic integration. This study aims to analyse the extent to which Malaysia’s participation in the RCEP can benefit the country’s growth and development. For this goal, a SWOT analysis will be carried out to assess the strength, weaknesses, opportunities and threats of joining RCEP, from Malaysia’s perspective. Findings suggest that Malaysia is indeed one of the main beneficiaries of the RCEP agreement in comparison to other ASEAN nations. However, much needs to be done by Malaysia to reap the benefits of the world’s largest trading bloc, while maintaining its national interests amidst a more liberal and open market setting.

Ammonia is considered a promising hydrogen carrier due to its high hydrogen density and liquefaction temperature. Considering that the energy efficiency generally decreases as chemical conversion is repeated, it is more efficient to directly use ammonia as a fuel for fuel cells. However, catalysts in direct ammonia fuel cells have the critical issues of sluggish ammonia oxidation reaction (AOR) rate and poisoning of reaction intermediates. In particular, the use of precious metal as cathodic catalysts has been limited due to ammonia crossover and poisoning. In this study, we introduce Fe-based single-atom catalysts with selective activity for the oxygen reduction reaction (ORR) even in the presence of ammonia. As the Fe content increased, the single-atom structure of the catalysts changed into Fe nanoparticles or carbides. Among our Fe–N–C catalysts, FeNC-50 with a Fe loading amount of 0.34 wt% showed the highest ORR performance regardless of the ammonia concentration. In particular, the difference in activity between the catalysts increased as the concentration increased. The FeNC-50 catalyst showed remarkable stability after 1000 cycles. Therefore, we believe that single-atom dispersion is an important factor in the development of stable non-precious catalysts with high activity and inactivity for the ORR and AOR, respectively.

Transition-metal phosphides (TMPs), a promising anode material for lithium-ion batteries (LIBs), are limited in application because of its serious volume effect in the cycle. In this work, a simple electrospinning strategy was proposed to restrict the grain size of CoP nanocrystals by nano-confined effect of carbon nanofibers with ligands. The addition of ligands not only could realize the uniform dispersion of CoP nanocrystals, but also strengthen the bond between the metals and carbon nanofibers. As a result, the CoP/CNF composite exhibits excellent lithium storage performance, and its reversible specific capacity could reach 1016.4 mAh g− 1 after 200 cycles at a current density of 200 mA g− 1. The research is anticipated to provide a new idea for the preparation of anode materials for lithium ion batteries.