We confirm whether Zr powders can restrain a rapid nitrification reaction and offer a stable oxidation reaction according to temperatures in nitrogen gas purification. A pellet-type, porous Zr getter is prepared (diameter: 10 and thickness: 3 mm) using Zr powder with an average particle size of 45 μm. While maintaining the whole system, the Zr getter reaction is confirmed with an increase in temperature from 150 to 550 oC at increments of 100 oC under 99.999 % purity nitrogen atmosphere comprising of 10 ppm of impurity. Surface color, pore size, stabilized layer, and phase change are confirmed with optical microscopy, SEM-EDS, Micro-Raman, and X-ray diffraction (XRD) according to the Zr getter temperature. The surface color of the Zr getter changes from metallic silver to dark gray as temperature increases. In the EDS results, the nitrogen component is not observed, and oxygen content increases from each surface at elevated temperatures. The Raman and XRD results show the oxidation layer as a result of 350 oC annealing. Therefore, the Zr getter can be applied as a nitrogen getter under 5-nine purity nitrogen atmosphere after appropriate oxidized pre-stabilization process to prevent rapid nitrification reaction.

The photovoltaic properties of perovskite solar cells (PSCs) with a carbon electrode fabricated using different annealing processes are investigated. Perovskite formation (50 oC, 60 min) using a hot-plate and an oven is carried out on cells with a glass/fluorine doped TiO2/TiO2/ZrO2/carbon structure, and the photovoltaic properties of the PSCs are analyzed using a solar simulator. The microstructures of the PSCs are characterized using an optical microscope, a field emission scanning electron microscope, and an electron probe micro-analyzer (EPMA). Photovoltaic analysis shows that the energy conversion efficiency of the samples fabricated using the hot-plate and the oven processes are 2.08% and 6.90%, respectively. Based on the microstructure of the samples and the results of the EPMA, perovskite is formed locally on the carbon electrode surface as the γ-butyrolactone (GBL) solvent evaporates and moves to the top of the carbon electrode due to heat from the bottom of the sample during the hot plate process. When the oven process is used, perovskite forms evenly inside the carbon electrode, as the GBL solvent evaporates extremely slowly because heat is supplied from all directions. The importance of the even formation of perovskite inside the carbon electrode is emphasized, and the feasibility of oven annealing is confirmed for PSCs with carbon electrodes.

한국산 개미과 뿔개미속의 2미기록종인 M. ademonia과 M. luteola가 분포함을 보고한다. 미기록종의 일개미에 대한 형태학적 특성과 사진을 제공한다.

We propose a novel stripping solution containing acids (HCl and HNO3), an oxidant [(NH4)2S2O8], and complexing agents (NaCl and citric acid) to remove surface passivation layers from 14K gold alloys fabricated using an investment casting process. The optimized solution employing only HCl acid is determined by varying molar fractions of HCl and HNO3 on 14K yellow gold samples. Stripping properties are also identified for red and white gold alloy samples under the optimized stripping conditions. The removal of passivation layers, weight loss, and microstructure evolution are characterized using Raman spectroscopy, a precision scale, and optical microscopy. The proposed stripping solution effectively removes passivation layers more rapidly than conventional cyanide stripping. Weight loss increases linearly for up to 5 min for all 14K gold alloys. Red gold exhibits the greatest weight loss, followed by yellow gold and white gold. The results of microstructural analysis reveal that the conformal stripping occurs according to time. These results imply that the proposed oxidative chloride stripping might replace conventional cyanide stripping.

This paper aims to experimentally and numerically explore fracture mechanism characteristics of ultra-thin chopped carbon fiber tape-reinforced thermoplastics (UT-CTT) hat-shaped hollow beam under transverse static and impact loadings. Three distinct failure modes were observed in the impact bending tests, whereas only one similar progressive collapse mode was observed in the transverse bending tests. The numerical model was to incorporate some hypothetical inter-layers in UT-CTT and assign them with the failure model as cohesive zone model, which can perform non-linear characteristics with failure criterion for representing delamination failure. The dynamic material parameters for the impact model were theoretically predicted with consideration of strain-rate dependency. It shows that the proposed modeling approach for interacting damage modes can serve as a benchmark for modeling damage coupling in composite materials.

한국산 개미과 배굽은침개미아과의 미기록종인 Discothyrea sauteri Forel을 보고한다. 종에 대한 형질과 사진, 한국산 배굽은침개미아과 속 검색표를 제공한다.

The ASEAN charter is a treaty established by ten member countries in the Southeast Asia founded on December 2008. Prior to the establishment of the Association of Southeast Asian Nations (ASEAN) charter, the Maritime Professional Education and Training Development Program was facing a challenge of disruptions relative to maritime events. Due to the disruptions of maritime events, challenges such as gap in international relations, lack of database integration in the field of maritime education and training, lack of knowledge transfer and no effective and proper framework of future development particularly in the areas of maritime education and training among the ASEAN countries existing. The goal of this paper is to motivate professionals and the relations society to collaborate in the Maritime Professional Education and Training Development: Today and Tomorrow, to be able to fill the gaps presented to this paper. In order to ensure this study can be completed in the right ways and times, the Critical Path Method (CPM) is used. As a finding of this study, all professional maritime members are expected to strengthening the international professional relations in maritime education and training system among the ASEAN region.

한국산 개미과 비늘개미속의 2미기록종인 Strumigenys alecto과 Strumigenys solifontis가 분포함을 보고한다. 2 종의 일개미에 대한 형질과 사진을 제공한다.

A warehouse is more than just a place to store goods but also creates a time utility gap between production and consumption that is important in the development of trade and commerce. Malaysia has a high aspiration to be the most popular gateway in Asia. However, Malaysia Productivity Corporation has claimed that particularly in efficiency and productivity aspects, the warehouse industry is less incline to innovate and make improvement to increase. There are ten failure factors that had been identified during literature survey affecting to the warehouse operations efficiency. Therefore, this study intends to analyse and select the main failure factors that mostly affecting the warehouse operations efficiency. A Fuzzy Analytic Hierarchy Process (FAHP) technique has been used in this study to calculate the weight value of each variable through a pair-wise comparison method. The finding highlighted the four main failure factors which are ‘equipment’, ‘environment concern’, ‘special handling consideration’ and ‘human factor’ that influence directly to the warehouse operations efficiency. This paper has contributed to a new knowledge of complex warehouse operation area with recommendations action that shall be taken to manage the possible risk in future, which will also contribute to achieve the government goals.

The Jeju Teachers' Association and Jeju Island Office of Education also proposes a visit to Japan to learn about their lives in connection with Korean schools in Japan. In 2020, Jeju National University and Ritsumeikan University plan to have the opportunity to jointly study and research the lives of Koreans in Japan from the standpoint of peace and human rights education. Based on the opinions of these international researchers, we should cover the human rights abuses committed under the US military administration and the responsibility for the deaths under US military influence, even after the establishment of the Korean government, and to restore the honor of 4.3 victims and survivors to prevent this from happening again. This is to protect peace and human rights in Jeju and the Korean peninsula.

The purpose of this paper is to examine some of the profound effects of Augmented Intelligence (AI) on Product, one of the “Four-Ps” of marketing: Product, Price, Place, and Promotion. Today’s customers are used to extreme convenience, beyond the brick-and-mortar shopping experience, and beyond online images. Customers increasingly demand more information, and more personalized information. This paper addresses how the presentation of products has changed. This paper is conceptual, based on a review of academic literature on marketing strategy, psychology, AI, and Machine Learning as chronicled in major marketing and business research journals.

The Straits of Malacca and Singapore is without hesitation, a vital sea lane of communication with the geographical advantage of linking the Indian and Pacific Oceans. Geographically, the Straits of Malacca and Singapore is shallow and fairly narrow on its eastern part and has created one of the most important traffic choke points in the world. Being a crucial sea-lane has experience the Straits with high density of vessel traffic. The increase in shipping activities has risen the challenge in safety of navigation and marine environmental protection problem which generally end up with huge financial losses for the seafarers and damages to the marine environment. Owing significant limitations in the geographical landscape, this article has primary objectives to examine how navigational safety and marine environment can be effectively protect using existing regulatory instruments. This article provides a review and analysis of existing laws and regulations to assess the status of navigational safety for marine environmental protection in the Straits of Malacca and Singapore. The article also evaluates potential strategies to this problem using insights from literature. The article finds out that the littoral States to the Straits of Malacca and Singapore should adopt more forward-looking perspective in the formulation of legal measures to enhance navigational safety for marine environmental protection. The article finally suggests the potential strategies for navigational safety and marine environmental protection in the Straits of Malacca and Singapore. This will help in setting priorities for future efforts in improving navigational safety for marine environmental protection with regard to international and regional initiatives.

The photovoltaic properties of TiO2 used for the electron transport layer in perovskite solar cells(PSCs) are compared according to the particle size. The PSCs are fabricated and prepared by employing 20 nm and 30 nm TiO2 as well as a 1:1 mixture of these particles. To analyze the microstructure and pores of each TiO2 layer, a field emission scanning electron microscope and the Brunauer–Emmett–Teller(BET) method are used. The absorbance and photovoltaic characteristic of the PSC device are examined over time using ultraviolet-visible-near-infrared spectroscopy and a solar simulator. The microstructural analysis shows that the TiO2 shape and layer thicknesses are all similar, and the BET analysis results demonstrate that the size of TiO2 and in surface pore size is very small. The results of the photovoltaic characterization show that the mean absorbance is similar, in a range of about 400-800 nm. However, the device employing 30 nm TiO2 demonstrates the highest energy conversion efficiency(ECE) of 15.07 %. Furthermore, it is determined that all the ECEs decrease over time for the devices employing the respective types of TiO2. Such differences in ECE based on particle size are due to differences in fill factor, which changes because of changes in interfacial resistance during electron movement owing to differences in the TiO2 particle size, which is explained by a one-dimensional model of the electron path through various TiO2 particles.

PURPOSES: Using recyclable materials in asphalt pavement industry is one of the essential tasks not only for saving construction budgets but also for mitigating environmental pollutions. Over the past decades, several efforts have been made by road maintenance agencies to incorporate various recyclable materials into virgin asphalt paving mixtures. As a result, reclaimed asphalt pavement (RAP), which consists of old pavement material was selected as one of most widely used recyclable materials. In this paper, the effects of using different amounts of single-recycled RAP (SRRAP) and double-recycled RAP (DRRAP) on the low-temperature characteristics of asphalt mixtures were investigated. METHODS: To evaluate the low-temperature characteristics of SRRAP and DRRAP mixtures, two experiments, the bending beam mixture creep test and semicircular bending fracture test were performed. The experimental parameters: creep stiffness, m-value, thermal stress, critical cracking temperature, fracture energy, and fracture toughness were computed then compared. RESULTS : RAP mixtures (SRRAP or DRRAP) showed lower mechanical performance compared with conventional asphalt mixtures. The differences became distinct with increased RAP addition. However, the performance differences between SRRAP and DRRAP mixtures were not significant in all cases, which indicate the possible application of re-recycling technology (DRRAP) in the asphalt pavement industry. CONCLUSIONS : The addition of RAP to virgin asphalt can mitigate low-temperature performance despite the improvement in fracture performance observed in some cases. Therefore, using RAP (SRRAP or DRRAP) mixtures on inter or sublayer construction, but not on the surface layer, is recommended. Moreover, the possibility of applying double-recycling technology in asphalt pavement industry can be introduced in this study because not significant performance differences were found between SRRAP and DRRAP mixtures especially at low temperature.

To produce carbon electrodes for use in perovskite solar cells, electrode samples are prepared by mixing various weight ratios of 35 nm nano carbon(NC) and 1 μm graphite flakes(GF), GF/(NC+GF) = 0, 0.5, 0.7, and 1, in chlorobenzene(CB) solvent with a ZrO2 binder. The carbon electrodes are fabricated as glass/FTO/carbon electrode devices for microstructure characterization using transmission electron microscopy, optical microscopy, and a field emission scanning electron microscopy. The electrical characterization is performed with a four-point probe and a multi tester. The microstructure characterization shows that an electrode with excellent attachment to the substrate and no surface cracks at weight ratios above 0.5. The electrical characterization results show that the sheet resistance is < 70 Ω/sq and the interface resistance is < 70 Ω at weight ratios of 0.5 and 0.7. Therefore, a carbon paste electrode with microstructure and electrical properties similar to those of commercial carbon electrodes is proposed with an appropriate mixing ratio of NC and GF containing a CB solvent and ZrO2.