This study is related to the development of lightweight automotive materials that were carried out to develop eco-friendly vehicles worldwide. High-strength aluminum alloy is used as one of the significant lightweight materials in the field of transportation machinery, and it is used as a lightweight material in various areas, including automobiles. The A356 alloy used in this study is an excellent aluminum alloy material that has widely used as a high strength aluminum alloy material in various forming methods. In this study, to examine the characteristics of the two alloys in which Mn and Sr elements were added to the A356 alloy and the A356 alloy, both alloys were manufactured by metal mold casting, which is a gravity casting method. The obtained specimens were heat-treated under the same conditions. In this study have investigated of the microstructure analysis, thermal analysis, crystal phase analysis, and mechanical property evaluation were performed to confirm how the added Mn and Sr elements influenced the microstructure, precipitate formation, and mechanical properties.

The change in pressure measurement according to the low pressure tap blockage rate of the Venturi flowmeter used in domestic nuclear power plants was approached numerically. Blockage rates were modeled dividing by 1/10dT to the downstream side of the low pressure tab to identify differential pressure changes. As a result, differential pressure increased in proportion to the blockage rate, and there was no change in differential pressure measurement at 10 to 40 percent with relatively small blockage rate, but the error rate of 50% to 0.3% or higher was shown.

Load carrying capacity(LCC) can be reduced from its design value as a result of film thickness change when a journal is misaligned and some part of bearing is unintentionally translated. In this study, the numerical solution of the incompressible Reynolds equation was obtained by using the finite difference method and mass conservation algorithm (JFO boundary condition) with periodic pressure distribution in circumferential direction to analyze the change of LCC due to journal misalignment and step change of film thickness in axial direction for a journal bearing of vertical pumps. Smallest LCC in each eccentricity ratio is obtained as two angular positions are changed – an angular position where misalignment occurs, and another angular position where the axial step takes place while the degree of misalignment is fixed at 90%. Compared with the reaction force of plain journal bearing, the LCC reduced as much as 26.7% due to geometric effects of journal bearing at the eccentricity ratio of 0.9, while the step height is no higher than 0.1 times of bearing clearance.

본 연구는 기존 선박에 자외선 (UV) 평형수처리장치(BWMS)를 설치 한 경우, 수치 계산을 통해 평형수 처리시간의 증가를 정량적으로 조사하였다. 계산 결과 배수량 55,000톤 가스 운반선의 평형수 처리시간은 UV BWMS 미설치 및 유량 제어 기능 없이 2.152 시간이었다. 평형수 처리시간은 UV BWMS 설치 후 14.2 % 증가했으며, 유량 제어 기능까지 고려 시 20.4 % 증가했습니다. 실제 조건들을 고려하면 UV BWMS 설치 후 평형수 처리시간은 기존 평형수처리시간 대비 최소 30 % 정도 증가할 것으로 예상됩니다. 따라서 업계 관계자는 평형수 처리시간 증가로 인한 선박 운영 손실을 최소화하기 위하여 UV BWMS 선정시 본선의 실제 평형수펌프 용량과 UV BWMS의 유동 에너지 손실을 충분히 고려하는 것이 좋습니다. 또한 BWMS 설치 후 평형수 처리시간 증가를 최소화하기 위해서는 더 큰 용량의 BWMS, 더 큰 파이프 및 내부 코팅이 있는 파이프 등의 사용을 고려할 수 있습니다.

국립수산과학원과 지역자치단체의 적조모니터링 결과를 바탕으로 해양환경 변동이 적조발생에 미치는 영향을 규명하였다. 1972년 적조 모니터링이 시작된 이후, 1980년대에서 1990년대까지 적조 발생은 지속적으로 증가를 하였으며, 1998년 109건의 최다 적조발생 이후 2010년대까지 감소 추세를 보이고 있다. 1970년대는 대부분 규조 적조가 발생하였으며, 1980년대에는 연안성 와편모조류가 주로 적조를 일으켰으며, 1993년 이후 Cochlodinium polykrikoides 적조가 지속적으로 발생하고 있다. 우리나라에서 수산피해를 일으킨 유해 적조 생물은 3종이다. 1981년 진해만에서 Karenia mikimotoi에 의한 고밀도 적조가 발생하여 패류가 대량 폐사하였다. 1992년 통영해역에서 Karenina sp.에 의한 적조가 발생하여 양식어류를 폐사시켰으며, 1995년 C. polykrikoides 적조로 765억 원의 최대 규모의 수산피해가 발생한 이후 지속적으로 발생하고 있다. 연안해역의 영양염 농도는 1980년대에 가장 높았으며, 1990년 중반 이후 매우 감소하고 있다. 이러한 영 양염 감소는 적조발생 감소를 잘 설명해 준다. 2016년 이후 30℃이상의 여름 고수온이 나타나며 C. polykrikoides의 적조 발생 범위와 규모 는 매우 감소하였다. 2016년 K. mikimotoi 적조가 전남 장흥∼고흥 해역에 발생하였으며, C. polykrikoides 적조는 여수해역에만 발생하였다. 2017년은 C. polykrikoides 적조 발생이 없었으며, Alexandrium affine 적조가 전남 여수∼경남 통영해역까지 발생하였다. 2018년은 평년에 비해 소규모 C. polykrikoides 적조가 발생하였다. 본 연구결과 우리나라 연안의 영양염 감소와 기후변화로 인한 고수온은 적조 발생에 영향을 주는 것으로 판단된다.

The purpose of this study was to investigate the qualitative changes of the citron by identifying the type of solution and addition of the solution to prevent the browning reaction of the citron in a way that inhibits the browning of the citron. The browning inhibitor solution was investigated using the individual and mixture, and the results of the degree of browning and chromaticity showed that vitamin C+NaCl+cyclodextrin (CD) had the lowest browning of 0.52. In chromaticity, the ΔE values indicate that the higher the value, the greater the change in color, and the lowest value of the vitamin C+NaCl+CD mixture was 47.0, indicating that there was minimal browning compared to other treatment. The active change of the polyphenol oxidase (PPO) in the citron increased enzyme activity as the browning progressed, and the vitamin C+NaCl+CD solution was the lowest at 68.40 μ/g among the anti-browning solution. Based on these research results, it seems that the CD mixing solution can be used as a citron browning inhibitor.

The purpose of this study was to evaluate the appearance, physicochemical, physical, and fermentation properties of the fermented soybean produced by manufacturing with inoculation the different types of microbial strains. The strains were inoculated by the NSI (natural strains inoculation), and the SSI (selective strain inoculation) were treatments. The appearance showed differences in color, viscous substance, and hardness depending on strains inoculation and fermentation duration. The pH, and total acidity were 6.40~7.26%, and 0.10~0.39% respectively with differences depending on the samples. The moisture content as the fermentation duration increased, the NSI (56.03~57.66%) decreased and the SSI (56.71~58.63%) increased. The physical characteristics of the hardness increased as the fermentation duration increased for the NSI and the SSI decreased. The color values for the L, a, and b values were 47.64~58.56, 7.15~9.08, and 12.41~17.30, respectively. The α-amylase and protease activities of the SSI were the highest among all treatments. The total viable cell counts of the fermented soybean products by strains were 5.02 to 9.77 log CFU/g, and SSI (fermentation, 48 hours) was the highest. The amino-type nitrogen contents of all samples were 301.62~746.97 mg% and the SSI showed the highest content. The amino acid had the highest glutamic acid content.

In the present work, an explicit finite element analysis technique is introduced to analyze the thermal stress fields present in the additive manufacturing process. To this purpose, a finite element matrix formulation is derived from the equations of motion and continuity. The developed code, NET3D, is then applied to various sample problems including thermal stress development. The application of heat to an inclusion from an external source establishes an initial temperature from which heat flows to the surrounding body in the sample problems. The development of thermal stress due to the mismatch between the thermal strains is analyzed. As mass scaling can be used to shorten the computation time of explicit analysis, a mass scaling of 108 is employed here, which yields almost identical results to the quasi-static results.

본 연구에서는 2009–2019년 기간 동안 대전시 외곽의 도심개발에 따른 인근 하천(관평천)의 상류, 중류, 하류의 구간에서 4회 조사(2009, 2010, 2016, 2019)를 통해 이화학적 수질, 어류 종 조성, 생태 건강성 특성에 대해 장기간 변화추이를 분석하였다. 본 하천지역에서 도심개발은 2008년에 이루어졌고, 2012년에는 하천복원사업이 수행되어 하천복원 전과 후의 특성변화 추이를 모니터링 하였다. 하천 생태건강도 평가를 위해 군집수준의 어류평가지수(Fish Assessment Index, FAI)를 이용하였고, 어류의 기관(Organ) 수준에서 해부학적 건강도(Necropsy-based Health Assessment Index, HAI) 분석을 실시 하였다. 이화학적 수질 분석에서는 중류(St. 2)에서 가장 낮은 탁도와 엽록소(Chl-a)가 측정되었다. 이는 빠른 유속에 의한 물리적 요인 때문으로 나타났다. 어류 조사에서는 총 18종이 채집되었고, 피라미(Zacco platypus)가 가장 우점 하는 종 (40.6%)으로 나타났다. 하천복원 직후(2016)에는 민감종(Sensitive species)과 충식종(Insectivore species)이 우점, 종 다양도 및 종 풍부도 지수 상승, 생태건강도 지수(FAI)가 상승하여 생태 건강도는 “최상상태(A: 87.5)”로 나타났으나 가장 최근 조사인 2019년에는 전 기간에 비해 악화되는 것으로 나타났다. 기관(Organ) 분석에 의거한 해부학적 건강도 지수(HAI) 분석에 따르면, 피부손상(Skin)은 상류에서, 신장 손상(Kidney)은 하류 역에서 나타났고, 간(Liver)과 아가미(Gill)의 손상은 모든 지점에서 나타나 해부학적 측면의 건강도에서도 영향을 받는 것으로 나타났다.

본 연구는 선교적 교회론 태동에 있어서 에큐메니칼과 복음주의 선교신학 안에 나타난 교회와 선교에 대한 선교신학 논쟁에 관한 연구이다. 두 진영이 갖고 있는 신학적인 입장과 차이들은 교회와 선교에 대한 서로 다른 진술들을 내놓았을 뿐만 아니라 선교에서의 교회 위치와 삶의 자리를 각각 달리 해석하는 결과를 가져왔다. 선교에 대한 교회 역할에 있어 에큐메니칼 입장은 사회 참여와 변혁적 삶에 보다 치중하는 신학을 강조했다면, 복음주의 입장은 복음 전도와 영혼구원, 교회 개척에 보다 치중하는 신학을 강조했다. 그럼에도 불구하고 두 진영의 인식론적 변화들은 화해를 모색하는 방향 전환이 이루어졌다. 선교에 있어서 교회의 삶의 자리는 복음 전도와 사회 참여가 동시에 이루어지는 것임을 새롭게 인식했다. 무엇보다 두 진영의 지속적인 협력 모색은 통전적 선교를 추구하는 방향으로 나아갔다, 또한 상호간의 선교신학 보완을 위해 화해를 모색하게 되었다.

This study was conducted to investigate changes on the quality characteristics of Prunus davidiana sugar extracts (PSEs) by processing conditions. The PSEs were prepared by extraction with commercial sucrose at 4°C or 25°C for 9 months with or without a pressure plate. The quality characteristics of PSEs were analyzed for Bxo, pH, total acidity, Hunter color value, alcohol content, polyphenol content, DPPH radical scaveging activity, and free sugar content. Bxo increased significantly while pH decreased with increased storage period (p<0.05). The PSEs stored at 4oC scored lower than those stored at 25oC for total acidity, alcohol content, and polyphenol contents. The PSEs with pressure plate possessed lower alcohol content and higher polyphenol content and DPPH free radical scavenging activity than those without pressure plate. The sucrose content in PSEs decreased with increased storage period, while glucose and fructose contents increased. These results indicate that by increasing storage period, sucrose in PSEs is decomposed into glucose and fructose, and the quality characteristics of PSEs such as total acidity, alcohol, and polyphenol content depend on processing conditions.

This study was conducted to investigate the quality of kimchi cabbages stored under a pallet unit-controlled atmosphere (PUCA), containing 2% O2 and 5% CO2, and to develop quality prediction models for cabbages stored under such conditions. Summer and winter cabbage samples were divided into PUCA-exposed groups and atmospheric airexposed control groups (in a cold storage). The control summer cabbages lost up to 8.31% of their weight, whereas the PUCA-exposed summer cabbages lost only 1.23% of their weight. Additionally, PUCA storage effectively delayed the reduction in cabbage moisture content compared with the control storage. After storage for 60 and 120 days of the summer and winter samples, respectively, the reducing sugar contents were higher in the PUCA groups than in the control groups. The linear regression analysis-derived equations for predicting the storage period, weight loss, and moisture content in the control groups, as well as those for predicting the storage period and weight loss in the PUCA groups, were appropriate according to the adjusted coefficient of determination, root mean square error, accuracy factor, and bias factor values. Therefore, this PUCA system would be useful for improving the shelf life of the postharvest summer and winter cabbages used in the commercial kimchi industry.

이 연구는 복분자에서 분리된 Lactobacillus plantarum stain (GBL16 및 17)을 포함한 probiotic에 대해 수행되었으며, 장내 미생물 변화를 확인하였다. Balb/c 마우스모델에서 GBL 16, 17을 포함한 시제품인 PMC와 시판중인 유산균 과자 BFY를 8주간 경구 투여 하였다. PMC의 투여는 장내 미생물총의 균형을 향상시키고, 장내개선에 긍정적인 영향을 보였다. 맹장을 이용한 NGS 분석을 통해 확인한 결과, 스트레스 후 증가하는 양상을 보이는 균인 Lachnospiraceae균이 감소하는 경향을 보였다. Alistipes균의 증가는 염증성 장 질환에 효과가 있을 것으로 판단되나, 추후 더 많은 연구가 필요할 것으로 보인다.

본 연구의 목적은 코로나19 팬데믹 사태가 가져올 국제질서의 변화에 대한 전망과 시사점을 분석하고 향후 한국이 나아갈 정책발전과 대안제 시를 위한 시사점을 도출하는 것이다. 특히 본 연구의 주안은 코로나19 사태를 통해 표출된 미‧중의 갈등과 이에 따른 국제질서의 변화를 전망 하는데 있다. 코로나19 팬데믹으로 인한 포스트 코로나 시대의 국제질서 는 탈(脫)세계화와 미‧중 전략경쟁 심화, 체제우월성 경쟁, 국가주의로 국 제적 거리두기의 탈(脫)세계화와 각자도생, 폐쇄적 국가주의의 범람 위 험, 국제 거버넌스를 갈구하는 양상을 띨 것으로 판단된다. 코로나19 팬 데믹을 통해 新안보 위협을 재인식하는 계기가 되었으며, 코로나19라는 신종 감염병, 新안보 위협의 대응을 통해 한국은 새로운 위협과 기회의 요인을 맞이하고 있다. 한국은 코로나19 팬데믹에 따른 포스트 코로나 시대에 대비하여 새로운 국제질서의 변화를 세밀하게 전망하고 대비책을 강구해야 한다. 특히 미‧중의 전략경쟁에 따라 기존의 패러다임 전환과 더불어 비전통적 안보위협인 신안보 개념에 입각하여 새로운 국제질서를 적극적이고 선제적으로 수용해야 할 것이다. 코로나19 팬데믹 극복 우수 사례 전파 등을 통해 신안보 분야 의제창출자로서 국제적 차원의 관심유 도와 협력을 주창하고, 신안보 위협 대응을 선도하여 위기를 기회로 바 꾸는 계기로 삼아야 할 것이다.

우리는 이번 코로나 19 사태를 통해 사회복지정책의 체계 및 구성요 소에 대한 구체적인 논의와 사회적 합의를 이끌어낼 책무가 있다. 보편 적이고 강력한 사회보장정책의 체계 및 구성요소를 재구축 및 재모색 하여 경제충격 뿐만 아니라 실질적인 코로나 19 사태 이후 삶의 질을 향상시킬 수 있도록 해야 할 것이다. 이를 위해 본 연구에서는 코로나 19에 대응하는 정부 및 지자체의 대응과 특히 긴급재난지원금에 대해 살펴보았다. 그리고 사회복지정책 및 보장의 역할과 이에 대한 새로운 논의 및 재구축과 관련해 살펴보고자 한다. 특히, 긴급재난지원금과 관 련한 많은 쟁점 및 논의 중 특히, 사회복지정책의 체계와 구성요소에 대한 논의 및 재정비를 통해 사회복지 및 보장 정책의 역할기대를 충 족시키기 위한 논의를 해보았다.

PURPOSES : The purpose of this study is to analyze the impact of the level of the light-environment and the driver's visual ability on the change in the driver's perception of a forward curved section at night. The study also aims to identify factors that should be considered to ensure safety while entering curved sections of a road at night. METHODS : Data collected from a virtual driving experiment, conducted by the Korean Institute of Construction Technology (2017), were used. Logistic regression was applied to analyze the effects of changes in the light-environment factors (road surface luminance and glare) and the driver’s visual ability on a driver's perception of the road. Additionally, analysis of the moderated effect of visual ability on light-environment factors indicated that the difference in drivers’ visual abilities impact the influence of light-environment factors on their perception. A driver's ability to perceive, as a response variable, was categorized into 'failure' and 'success' by comparing the perceived distance and minimum reaction sight distance. Covariates were also defined. Road surface luminance levels were categorized into 'unlit road surface luminance' (luminance ≤ 0.1 nt) and 'lit road surface luminance' (luminance > 0.1 nt), based on 0.1 nt, which is the typical level observed on unlit roads. The glare level was categorized as 'with glare' and 'without glare' based on whether the glare was from a high-beam caused by an oncoming vehicle or not. The driver's visual ability level was categorized into 'low visual ability' (age ≥ 50) and 'high visual ability' (age ≤ 49), considering that after the age of 50, the drive’s visual ability sharply declines. RESULTS : The level of road surface luminance, glare, and driver's visual ability were analyzed to be significant factors that impact the driver's ability to perceive curved road sections at night. A driver's perception was found to reduce when the road surface luminance is very low, owing to the lack of road lighting ('unlit road luminance'), when glare is caused by oncoming vehicles ('with glare'), and if the driver's visual ability level is low owing to an older age ('low visual ability'). The driver's ability to perceive a curved section is most affected by the road surface luminance level. The effect is reduced in the order of glare occurrence and the driver's visual ability level. The visual ability was analyzed as a factor that impacts the intensity of the effect of change of the light-environment on the change of the driver's ability to perceive the road. The ability to perceive a curved section deteriorates significantly in 'low visual ability' drivers, aged 50 and above, compared to drivers with 'high visual ability,' under the age of 49, when the light-environment conditions are adverse with regard to the driver’s perception (road surface luminance: 'lit road surface luminance'→'unlit road surface luminance,' glare: 'without glare'→'with glare'). CONCLUSIONS : Supplementation, in terms of road lighting standards that can lead to improvements in the level of light-environment, should be considered first, rather than the implementation of restrictions on the right of movement, such as restricting the passage of low visual ability or aging drivers who are disadvantageous in terms of gaining good perception of the road at night. When establishing alternatives so that safety on roads at night is improved, it is necessary to consider improving drivers' perception by expanding road lighting installation. The road lighting criteria should be modified such that the glare caused by oncoming traffic, which is an influential factor in the linear change in perception, and the level of light-environment thereof are improved.

본 연구는 반응성애착장애 유아의 언어 및 놀이발달의 변화과정을 그림책 읽어주기와 놀이참여를 통한 상담자의 개입으로 2018년 6월15일부터 2019년 1월 30일까지 주 2회 총 56회기로 약 7개월여 동안 단일대상으로 탐색연구 하였다. 상담자는 유아의 반응에 일관적이며 수용적인 태도로 자극을 촉진하고, 민감한 반응으로 상호작용하였다. 이에 따른 반응성애착장애 유아의 언어 및 놀이발달 변화과정은 다음과 같이 6단계로 나타났다. 첫째, 자극-불안정 접촉의 혼란스러 운 단계. 둘째, 자극-접촉의 안정의 단계. 셋째, 자극-촉진 수용의 단계. 넷째, 자극-습득 내면화 단계. 다섯째, 자극-표현 변화의 단계. 여섯째, 자극-확장 적 응의 단계로 변화하면서 유아는 일상생활에 적응하며 자신의 세계를 구축하였 다. 이러한 변화의 과정은 반응성애착장애 유아의 부모나 다양한 치료 현장의 상담사, 유아교육현장 교사들에게 개입을 위한 길잡이가 되어줄 것이다.

The planning acumen led by the crown prince stands out during the banquets that were held continually during the reign of Crown Prince Hyomyung around the late Joseon period from 1827 to 1929. If we examine the changes in banquet space during the period that Crown Prince Hyomyung ruled by proxy, the Jagyeongjeon(慈慶 殿) in Changgyeonggung Palace, which was built during the time of King Jeongjo was repaired after the in 1827 during the reign of the crown prince and appeared in its changed form in Muja Jinjakin 1828. It is believed that the Jagyeongjeonwas expanded and repaired during the reign of Crown Prince Hyomyung to conduct banquets for important guests. Jagyeongjeon which was repaired during the crown prince's reign, is a space where banquets were continuously held during the three years that he reigned, and we can see that it is an important space for royalty where the authority of King Sunjo, Queen Sunwon, and Crown Prince Hyomyung was reflected. Yeongyeongdan(演慶堂) was a structure built in 1828, which is after the period when the Jagyeongjeonwas changed in 1827, and it is a space that emerged during the reign of the crown prince. Hwanchwijeong(環翠亭), which was constructed during the time of King Seongjong was changed after 1827 during the reign of Crown Prince Hyomyung and appeared in its changed form in Muja Jinjakin 1828. Hwanchwijeongwas the place where the Crown Prince Hyomyung stayed and planned banquets and it was repaired along with Jagyeongjeonin 1827. During his reign, the political intent of the crown prince was reflected not in superficial political spaces but in spaces where banquets were held and accordingly the main spaces for banquets and their related royal palace locations were changed or newly established. You need to briefly explain what this and Muja Jinjak are. New information is not provided in this paragraph. You have already established why the crown prince renovated the banquets and its significance in the first two paragraphs. You could just add “Jagyeongjeon(慈慶殿), Yeongyeongdan(演慶堂), and Hwanchwijeong(環翠亭) in Changgyeonggung Palace during his reign were changed and renovated during the time when the royal banquets of the 19th century were getting established. It was spaces that reflected the royal family and royal authority” to the end of the second paragraph and it would convey your intended meaning.