In the present study, it is conducted to understand the heating performance and compressor operation characteristics according to 7 indoor unit combinations and 3 setting temperatures of the inverter multi-heat pump under heating standard temperature conditions. Heating capacity, COP and compressor frequency are investigated using the multi-calorimeter. The indoor unit combinations are simultaneous operation(A+B+C), partial operation(A+C, A+B, B+C) and independent operation(A, B, C), and the setting temperature is 20, 21, and 30°C. Since the increase in the setting temperature increases the compress frequency, the heating capacity increases, but COP decreases due to the increase in power consumption. The frequency increases as the indoor unit combination capacity increases, and decreases as the setting temperature decreases in the steady state.

Beta-titanium alloys are used in many industries due to their increased elongation resulting from their BCC structure and low modulus of elasticity. However, there are many limitations to their use due to the high cost of betastabilizer elements. In this study, biocompatible Ti-Mo-Fe beta titanium alloys are designed by replacing costly betastabilizer elements (e.g., Nb, Zr, or Ta) with inexpensive Mo and Fe elements. Additionally, Ti-Mo-Fe alloys designed with different Fe contents are fabricated using powder metallurgy. Fe is a strong, biocompatible beta-stabilizer element and a low-cost alloying element. The mechanical properties of the Ti-Mo-Fe metastable beta titanium alloys are analyzed in relation to the microstructural changes. When the Fe content increases, the tensile strength and elongation decrease due to brittle fracture despite a decreasing pore fraction. It is confirmed that the hardness and tensile strength of Ti-5Mo-2Fe P/M improve to more than 360 Hv and 900 MPa, respectively.

블록체인 기술을 기반으로, 환금성이 있는 NFT(Non-fungible token) 또는 가상화폐가 게 임이용의 결과물로서 이용자에게 귀속되는 P2E (Play to Earn) 게임 모델이 새로이 등장하였다. 그러나 게임물관리위원회는 P2E 게임의 사행성 을 이유로 등급분류를 거부하거나 취소하여 국내 시장 유통을 금지하고 있다. 반면 우리나라를 제 외한 많은 국가들에서는 P2E 게임이 활발하게 이용되고 있어 게임위 판단의 근거를 검토할 필 요가 있다. 게임위는 법률상 사행성게임물에 대한 등급분 류를 거부하거나 취소할 수 있는데, 이때 사행성 게임물 판단을 위한 근거규정이 미비하다는 문제 가 있다. 사행성게임물은 법률상 사행행위(베팅, 배당, 경마 등)를 내용으로 하거나 게임의 결과가 우연적으로 결정되는 게임물로서 이용자의 자산 에 손익을 미치는 것으로 정의되는데, NFT 혹은 가상자산이 이용자의 자산에 이익이 된다는 이유 만으로 그 게임물의 내용과 상관없이 사행성게임 물로 규정하는 것은 잘못이다. 또한 이용자의 재 산상 손익을 끼칠 수 있는지에 대한 구체적인 판 단 기준을하위법령에위임하고있으나, 위임받은 법령과 게임위 내규에서는 별도로 다루지 않고 있어 판단기준에 공백이 있다. 한편 게임물의 사행성은 게임물의 등급분류에 영향을 미치는데, 사행성게임물이 아니라면 사행 성이 인정되더라도 등급분류에 따라 게임출시가 가능하다. 게임산업법은 사행적인 게임물의 환전 행위를금지하고있는데, P2E 게임의환전가능성 을 이유로 사행성게임물로 판단하는 것은 잘못된 적용이다. 더불어 경품 등의 제공을 통한 사행성 조장을 금지하고 있는데, P2E 게임 이용자에게 제공되는 결과물은 그 형태와 관계없이 경품 등 에 해당하므로 사행성을 조장한다고 볼 수 있다. 그러나 게임물의 사행성 판단에 대해서는 사회⋅ 경제적 상황과 업계종사자의 의견을 반영하여 탄 력적으로 규율하는 것이 바람직하다.

Fishery products play an important role in Korean food culture, and awareness of the safety of fishery products is increasing in the seafood market. Against this backdrop, Japan has announced a plan to release radioactive water to the sea from 2023. In the case of Korea, it is adjacent to the area to be discharged, so there are concerns about securing the safety of marine products. Therefore, it is necessary to analyze the change in perception and impact of marine product consumers due to the discharge of contaminated water and to study appropriate countermeasures when discharging contaminated water from nuclear power plants. In this study, the current status of radioactive contaminated water discharge in Japan was summarized, and a survey was conducted on the change in the consumption perception of marine products according to the discharge of contaminated water to analyze the factors affecting the consumption change of domestic consumers. According to the survey, 85.3% of the respondents said that it will affect the purchase of domestic marine products if Japan starts discharging contaminated water from nuclear power plants. Moreover, 85.5% of the respondents said it will affect the purchase of imported marine products.

The effect of change in exchange rates on an economy is very important, especially, to a small open economy like South Korea. I explore whether Free Trade Agreements (FTAs) have positive influences on exchange rate-pass through import price of import market for fishery products in South Korea. Competition among FTA partners is enhanced after FTAs are effective. I expect that the extent to which are exchange rate pass-through (hereafter, ERPT) into import price of fishery products (in terms of Korea currency) would be reduced since the import market for fishery products in South Korea is an oligopolistic market. Specifically, I　investigate two research questions with six South Korea’s FTA partners─Norway, Thailand, Peru, U.S., China and Vietnam. First, whether the extent to which are exchange rate pass-through into import price of fishery products from six FTA partners would decrase in the post-FTA era; seconds, the size of reduction has a negative relation with the size of their market share in the import market for fishery products in South Korea if it decreases. The empirical results indicate that the degree of ERPT into import price from other FTA partners than Norway has been reduced after FTA, statistically and significantly; however, I do not find the evidence that the size of reduction is related to their market share. The findings in this study imply that FTAs have negative effects on producers’ economic welfare in South Korea’s fishery industry by reducing the extent to which are exchange rate pass-through as well as reducing tariff barriers.

콩 [Glycine max (L.) Merr.]은 단백질, 지방, 탄수화물의 3대 영양소와 다양한 기능성 성분의 주요 공급원이다. 녹색종피와 자엽을 가진 콩 품종은 눈건강에 유익한 루테인 성분을 많이 함유하고 있지만, 항영양성분으로 알려진 쿠니츠트립신인히비터 단백질, 렉틴 단백질 및 P34 단백질을 가지고 있어 품질과 기능성을 저하시킨다. 이러한 성분이 유전적으로 제거된 품종의 육성이 필요하다. 녹색종피와 자엽을 가지고 있지만, 쿠니츠트립 신인히비터, 렉틴, P34의 3가지 단백질이 모두 없는 triple null 유전자형을 가진 콩 계통을 육성하기 위하여 본 연구가 진행되었다. 4개의 유전자원 (Gaechuck#2, PI548392, PI567476, Seonyack)을 이용하여 창성된 두 모본의 교배로 육종집단이 창성되었다. Western blot 기술을 이용하여 쿠니츠트립신인히비터, 렉틴 및 P34 단백질의 존재여부를 확인하였다. 녹색종피 및 자엽과 쿠니츠트립신인히비터, 렉틴, P34의 3가지 단백질이 모두 없는 triple null 유전자형 (titilelep34p34)을 가진 6개의 F2 종자가 선발되었다. F2 식물체 세대와 농업형질 평가를 통하여 한 개의 계통이 선발되었으며 F4 종자에서 3가지 단백질에 대한 유전적 고정을 확인하였다. 선발 계통의 경장은 73 cm 정도였으며 백립중은 19.5 g으로 중립에 속하였고 종피색은 녹색이고 제색은 검정색이며 성숙 자엽색은 녹색이었다. 본 연구를 통하여 선발된 계통은 성숙 콩 종실에서 품질과 기능성을 저하시키는 쿠니츠트립신인히비터, 렉틴, P34의 3가지 단백질이 모두 없으며 녹색종피와 자엽을 가진 유색콩 품종 육성을 위한 재료로 이용될 수 있을 것으로 사료되었다.

Zintl phase Mg3Sb2 is a promising thermoelectric material in medium to high temperature range due to its low band gap energy and characteristic electron-crystal phonon-glass behavior. P-type Mg3Sb2 has conventionally exhibited lower thermoelectric properties compared to its n-type counterparts, which have poor electrical conductivity. To address these problems, a small amount of Sn doping was considered in this alloy system. P-type Mg3Sb2 was synthesized by controlled melting, pulverizing, and subsequent vacuum hot pressing (VHP) method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate phases and microstructure development during the process. Single phase Mg3Sb2 was successfully formed when 16 at.% of Mg was excessively added to the system. Nominal compositions of Mg3.8Sb2-xSnx (0 ≤ x ≤ 0.008) were considered in this study. Thermoelectric properties were evaluated in terms of Seebeck coefficient, electrical conductivity, and thermal conductivity. A peak ZT value ≈ 0.32 was found for the specimen Mg3.8Sb1.994Sn0.006 at 873 K, showing an improved ZT value compared to intrinsic one. Transport properties were also evaluated and discussed.

An ecological niche is defined as the specific role of a species influenced by time, space, and other resources. By investigating overlaps between ecological niches of different species, we could estimate the degrees of interspecific competition. Such studies often use geographic information systems (GIS) to discover niche overlaps between species. In this study, we used GIS to estimate the spatial niches of two Korean frog species (Pelophylax nigromaculatus and P. chosenicus). This enabled us to predict their geographic distributions in order to identify their coexistence regions and distribution patterns. The results confirmed that altitude was an important variable for predicting their distribution, with a correlation with their climatic range. Spatial distributions of the two frog species were highly overlapped, as the distribution range for P. nigromaculatus included most of the range of P. chosenicus, showing a sympatric distribution pattern. Within the coexisting regions, however, the presence sites for the two species did not overlap, implying weak competition. To confirm the principal factors influencing their competitive relationship and reasons for their sympatric distribution pattern, we need more detailed in-depth studies on the diverse environmental variables within the regions where the two species coexist. By doing so, we would be able to identify various mechanisms for avoiding competition in sympatric frog species.

In this study, the Euro NCAP-based AEB system evaluation simulation was conducted by applying the calculated corrected TTC by road condition estimation of scenarios (CPFA, CPNC, CPLA) of the V2P situation scenario using PC-Crash, a program used for traffic accident analysis. The scenario was evaluated in consideration of the two road conditions. the low-speed conditions among every scenarios avoided collision, but in the medium and high-speed conditions has been collided with pedestrian. It was confirmed that the time point at recognizing pedestrian was lower than set TTC at which AEB system was operated, even though the AEB was operated immediately, a collision occurred due to insufficient braking distance. As in this study, if studies such as V2V, V2P, and V2B considering road friction are actively conducted, it is expected to be useful data for automobile accident prevention and accident analysis.

MMBR system has been suggested as a promising system to resolve harvesting problems induced from low settling efficiency of microalgae. And recently, a lot of research on reducing fouling at the MMBR system has investigated focused on EPS in many cases. EPS of microalgae mainly consists of polysaccharides and protein components, and is produced through photosynthesis and nitrogen-carbon metabolic pathways. Especially, P-EPS is one of major compounds which occur membrane fouling phenomenon, as its hydrophobic protein components cause floc formation and cake layer accumulation. And it is already known that almost every microalgae can metabolize P-EPS or Chl-a when nitrogen sources as a substrate is insufficient or exhausted situation. With the above backgrounds, uptake rates of P-EPS or Chl-a by Scenedesmus quadricauda according to the type of carbon source and nitrogen concentration were evaluated in order to verify correlation between carbon source vs P-EPS production, and indeed Scenedesmus quadricauda uses P-EPS or Chl-a when the amounts of nitrogen sourc es in the feed is not satisfied. As a result, it was shown that P-EPS and Chl-a production were increased proportional to nitrogen concentration under organic carbon condition. And especially, the amo unts of P-EPS and Chl-a in the cell were diminished with the nitrogen source becomes insufficient or exhausted. Because P-EPS accelerates fouling at the MMBR system, P-EPS degradation by Scenedesmus quadricauda in order to get nitrogen source may contribute to reducing fouling. About a affects of N-consumed Chl-a to the MMBR fouling, more survey is needed. On the contrary, considering the purpose of MMBR system of this study, i.e. harvesting useful high value microalgae efficiently feeding adequate industrial process wastewater, it seems like difficult to maintain satisfied metabolic activity and to harvest with high yield rate using nitrogen-poor MMBR feed.

Based on the multilingual perspective that emphasizes that non-native variants of English need to be recognized as having values equivalent to the native speakers’ English, this study aimed at discovering elementary school teachers’ perceptions and beliefs of native-speakerism, multilingualism, and monolingualism in English education, and the contradictions and questions they had as they reflected on the language ideologies. Nine elementary teachers participated in the study, and two written reflections on language ideologies and two follow-up group interviews were used as the data source. The findings were as follows. First, the teachers confirmed, consolidated, or realized how native speakerism and monolingualism were deeply rooted in English teaching and learning. However, they showed that they had agency in their own teaching, and also showed changes in their perception through reflecting on their experiences. Last, the teachers had questions and contradictions about implementing a multilingual approach in teaching English, which provides the issues and challenges to be solved for the transformation of English education in the multilingual world. This study has implications for primary English education.

Pilot-scale coagulation and sedimentation processes were operated to investigate the T-P (Total phosphorus) removal efficiency. A multiple regression model was also derived to predict the water quality improvement effect with river water characteristics. The inflow rates for the pilot-scale facility were 157–576 m3/day, and the coagulant doses were in the range of 13.7–58.5 mg/L (average 38.9 mg/L) for PAC (Poly alum chloride) and 16.5–62.1 mg/L (average 36.0 mg/L) for alum. The results found that the influent BOD (Biochemical oxygen demand) and T-P concentrations were 4.9 mg/L and 0.115 mg/L, and the removal efficiencies were 52.7% and 59.4%, respectively. T-P removal efficiencies on wet weather days were higher by 10% than dry weather days because influent solids influenced T-P's coagulation process. The pH of river water was 6.9–7.8, and the average pH was 7.3. Although the pH variation was not significant, the trend showed that the treatment efficiency of T-P and PO4-P removal increased. Thus, the pH range considered in this study seems to be appropriate for the coagulation process, which is essential for phosphorous removal. The T-P removal efficiencies were 19.6–93.3% (average 59.2%) for PAC and 16.4–98.5%(average 55.9%) for alum; thus, both coagulants showed similar results. Furthermore, the average coagulant doses were similar at 42.4 mg/L for PAC and 41.3 mg/L for alum. When the T-P concentration of the effluent was compared by the [Al]/[P] ratio, the phosphorus concentration of the treated water decreased with an increasing [Al]/[P] ratio, and the lowest T-P concentration range appeared at the [Al]/[P] ratio of 10–30. A seasonal multiple regression analysis equations were derived from the relationships between 10 independent and dependent variables (T-P concentration of effluent). This study could help lake water quality maintenance, reduce eutrophication, and improve direction settings for urban planning, especially plans related to developing waterfront cities.