The overall process, from the pre-treatment of aluminum substrates to the eco-friendly neutral electroless Ni-P plating process, was observed, compared, and analysed. To remove the surface oxide layer on the aluminum substrate and aid Ni-P plating, a zincation process was carried out. After the second zincation treatment, it was confirmed that a mostly uniform Zn layer was formed and the surface oxide of aluminum was also removed. The Ni-P electroless plating films were formed on the secondary zincated aluminum substrate using electroless plating solutions of pH 4.5 and neutral pH 7.0, respectively, while changing the plating bath temperature. When a neutral pH7.0 electroless solution was used, the Ni-P plating layer was uniformly formed even at the plating bath temperature of 50 oC, and the plating speed was remarkably increased as the bath temperature was increased. On the other hand, when a pH 4.5 Ni-P electroless solution was used, a Ni-P plating film was not formed at a plating bath temperature of 50 oC, and the plating speed was very slow compared to pH 7.0, although plating speed increased with increasing bath temperature. In the P contents, the P concentration of the neutral pH 7.0 Ni-P electroless plating layer was reduced by ~ 42.3 % compared to pH 4.5. Structurally, all of the Ni-P electroless plating layers formed in the pH 4.5 solution and the neutral (pH 7.0) solution had an amorphous crystal structure, as a Ni-P compound, regardless of the plating bath temperature.

Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets (10×10 mm mesh size), scoop-nets (4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the ‘b’ value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.

Air curtains, blowing air streams across a doorway, were installed in trial trains on subway line 7 in 2021 and they have been operated with dust collectors to improve the air quality of subway trains. In this study, we investigated the effects of air curtains on the indoor air quality in the trial subway trains. The concentrations of PM2.5 and carbon dioxide in the four selected cabins were measured in the morning hours (e.g., 7:30–11:30 am including the morning rush hour). The measurements were conducted on February 26, March 31, April 30, and May 14, 2021 and air curtain (AC)s and dust collector (DC)s in the four cabins were operated differently on those measuring days. All devices were turned off in the control cabin and only ACs, only DCs, and both the ACs and DCs were turned on in the other three cabins, respectively. The 4-h-averaged PM2.5 concentrations in the cabins, where only ACs and only DCs are turned on, are lower than in the control cabin by 18% and 26%, respectively. In addition, the joint operation of ACs and DCs can decrease the PM2.5 concentration by up to 42%. The time series of PM2.5 concentrations, measured on April 30, illustrate again that ACs block the intrusion of outside particulate matters. The 4-h-averaged carbon dioxide concentrations in the four cabins do not show monotonic differences between the cabins because of the generation of carbon dioxides inside the cabins. When the weights of individual cars and thus the numbers of passengers are similar between the cabins, the carbon dioxide concentrations in the ACs-operated cabins are higher than in the control cabin. This indicates that ACs can block the outward emission of carbon dioxides and maybe other indoor air pollutants as well.

본 연구의 목표는 S. boulardii 유래 세포벽 추출물 (CWSB)의 첨가가 반추위 발효에 미치는 영향을 평가하는 것이다. 본 연구의 in vitro 발효 실험은 CWSB의 첨가용 량이 다른 2개의 실험으로 구성되었다. 실험 1에서는 대 조구(CON, 시험사료)와 CWSB0.05(시험사료+CWSB 0.5g/kg 첨가), CWSB0.075(시험사료+CWSB 0.75g/kg 첨 가)의 처리구로 구성되었고, 실험 2의 처리구는 대조구 (CON, 시험사료)와 CWSB0.5(시험사료+ CWSB 5g/kg 첨 가), CWSB1.0(시험사료+CWSB 10g/kg 첨가)의 처리구로 구성되었다. In vitro 배양 이후 3, 6, 12, 24, 48h 동안 발 생한 가스 발생량 및 48h 배양 이후 발효 성상을 분석하 였다. 실험 1에서는 CWSB0.05 처리구에서 유의적으로 높 았던 Vmax(p<0.01)를 제외한 모든 반추위 발효성상에서 처 리구간 유의적 차이가 관찰되지 않았고, 이에 따라 사료 내 0.5%, 1%의 고용량 첨가 수준을 설정한 실험 2를 수행 하였다. 실험 2에서의 CWSB1.0 처리구는 대조구에 비해 총 VFA 발생량이 유의적으로 높았으나 전체 배양시간 내 가스 발생량 및 건물 소화율, 섬유소 소화율은 대조구와 유의적인 차이를 나타내지 않았다. 본 연구 결과를 종합 해 볼 때, CWSB의 첨가수준은 0.5% 이상에서 반추위 발 효 개선효과를 나타낼 것으로 추정된다.

본 연구는 소비자가 경험재인 웹소설을 선택하는 상황에서 사실적 메시지와 평가적 메시지를 담은 온라인 리뷰를 보았을 때 더 유용하다고 판단하는 리뷰가 무엇인지 탐색하고, 이러한 유용성 평가의 차이에 대한 개인의 분석적 의사결정 성향 수준의 조절효과를 검증하기 위하여 실시되었다. 경험재를 구매하기 전 객관적 정보를 수집하는 소비 자의 성향에 근거하여 웹소설의 소비자는 사실적인 온라인 리뷰의 유용성을 더 높이 평가할 것으로 예상하였다. 또 한 인지적 성향에 따라 구분되는 의사결정 유형 중 분석적 의사결정자는 정확한 정보를 수집하여 논리적인 판단을 내린다. 따라서 분석적 의사결정 성향 수준이 높아짐에 따라 사실적인 온라인 리뷰의 유용성 평가가 높아질 것으로 예상하였다. 실험 1의 결과 사실적인 리뷰를 제시받은 집단이 평가적인 리뷰를 제시받은 집단보다 리뷰의 유용성을 높이 평가하였으며, 실제 웹소설 선택 상황과 유사하게 두 유형의 리뷰를 동시에 제시한 실험 2에서도 리뷰의 유용 성 평가에 대한 리뷰 메시지 유형의 주효과가 확인되었다. 또한 실험 2에서는 분석적 의사결정 성향 수준이 높아짐 에 따라 사실적인 리뷰의 유용성을 높이 평가하는 경향이 드러나 분석적 의사결정 성향 수준의 조절적 역할이 확인 되었다. 본 연구는 경험재인 웹소설을 선택하는 상황에서 리뷰 메시지 유형 및 소비자의 분석적 의사결정 성향 수준 이 소비자의 리뷰 유용성 평가에 영향을 끼친다는 사실을 확인함으로써 웹소설 소비자의 행동 양식을 밝혔다는 이론 적, 실무적 의의를 갖는다.

In order to analyze the pressure drop of the fluid passing through the hydraulic coupler, a flow model using the Computational Fluid Dynamics (CFD) analysis technique was developed and the fluid flow rate and pressure distribution inside the coupler were analyzed. The analysis model was corrected by comparing the pressure drop measurement using a 6.35mm hydraulic coupler with the ISO reference value and the simulation prediction value. Using the calibrated model, the flow rate and pressure drop of 13 types of hydraulic couplers distributed on the market were analyzed, and their performance was determined by comparing them with ISO reference values. In the case of type A coupler, the pressure drop was generally higher than the ISO reference value, and in the case of type B coupler, the pressure drop was similar to or lower than the ISO reference value. It was confirmed that the complex flow analysis inside the hydraulic coupler could be easily performed through computational fluid dynamics (CFD) modeling, and based on this, problems could be identified and performance could be improved performance.

본 연구는 백두대간 생태축 복원사업지에서의 수목 생육 장애 요인을 평가하기 위해서 토양 및 미기상 환경모니터링 을 실시했다. 그 결과 복원 사업지에서는 주변 산림과 비교하여 토양의 유기물, 전질소 및 양이온치환용량이 부족하여 양분 공급이 결핍된 것으로 나타났다. 복원사업 준공 직후인 가을철 토양수분은 복원사업지가 주변 임내와 비교하여 7배 이상 빠르게 감소했으며, 미사질과 점토 함량 부족으로 인해 보습력이 매우 낮은 것으로 평가되었다. 복원 사업지의 경우 주변 임내와 비교하여 연간 잠재증발산량이 약 2배 높은 975㎜로 분석되었다. 복원사업지의 여름철 토양 수분은 일사량이 증가하는 낮 시간대에 급격하게 감소하는데 이는 잠재증발산량 증가의 영향이 큰 것으로 나타났다. 이상의 수목 생육 장애 요인을 개선하기 위해서는 낙엽, 부엽토, 토양개량제, 유기질 비료 시비 등을 활용하여 보습력 증진 등 물리성 개량과 양이온치환능을 증가시켜 식물에게 원활한 양분 공급이 이루어질 수 있도록 유도해야할 것으로 판단된다. 본 연구의 결과는 향후 생태축 복원사업의 설계와 시공 및 관리방안 수립의 기초 자료가 될 수 있을 것으로 기대된다.

강원 지역 두타산과 청옥산에 자생 중인 분비나무림의 종조성 분석을 통한 식생 구조를 파악하기 위해 식물사회학적 방법에 따른 현장조사와 군집 분류를 시행하였다. 분비나무가 자생하고 있는 임분을 대상으로 약 400㎡ 면적의 조사구 18개소를 설정하고 현장조사를 시행하였으며, 이원지표종분석(TWINSPAN)을 통하여 군집을 분류하고 DCA (Detrended Correspondence Analysis)를 통해 시각화하였으며, 분류된 군집 별 종다양도 분석, 중요치 분석, 흉고직경 급 분포도 분석을 통해 각 군집 별 특성을 파악하고자 하였다. 그 결과, 강원도 두타산과 청옥산의 분비나무림은 Group Ⅰ,Ⅱ,Ⅲ,Ⅳ 등 총 4개의 군집으로 분류되었다. Group Ⅰ은 신갈나무, 분비나무 등의 순으로 우점하는 신갈나무- 분비나무 경쟁림이며, Group Ⅱ는 분비나무, 마가목, 사스래나무 등의 순으로 우점하는 분비나무-사스래나무 경쟁림이 다. Group Ⅲ는 분비나무가 우점하나, 다수 존재하는 낮은 직경급 신갈나무로 인해 앞으로 분비나무-신갈나무의 경쟁이 예상되며, Group Ⅳ는 분비나무, 마가목, 신갈나무 등의 순으로 우점하며 분비나무가 모든 층위에서 우점중인 임분으로 조사되었다. 강원도 두타산과 청옥산 일대 분비나무림의 종다양도는 설악산, 백두대간 닭목령-댓재구간, 오대산 등 타지역 분비나무림의 종다양도에 비해 대체로 낮았으며, 열악한 생육환경과 신갈나무 등 활엽수종과의 경쟁관계가 예상되어 지속적인 모니터링과 보전대책 수립이 필요하다.

An increasing trend embracing the 2030 generation mindset through the new word ‘newtro’, which means reinterpreting the past and selling it in the present, has been gaining traction. The 2030 generation who seek new experiences and desserts is growing. The unique dessert market is expected to continue to grow in the future. Thus, this study devised a pine needle madeleine. Madeleines were made by varying the proportions of pine needle powder added to 0%, 1%, 3%, 5%, and 7%, and specific gravity, moisture, color, physical properties, and antioxidant properties were measured. The L-value decreased significantly (p<0.001) as the amount of pine needle powder added increased, and the a-value increased (p<0.001). The total polyphenol content, DPPH, and ABTS gradually increased significantly (p<0.001). Through this study, it was possible to confirm the quality and characteristics of madeleines using pine needle powder, which has excellent antioxidant properties, and it will become basic data for the development of various desserts using pine needle powder.

To improve the shelf-life of Centella asiatica, Centella asiatica was treated with gel packs containing slow-released chlorine dioxide (ClO2) gas at 3-5 ppm for 20 days at 4℃. The weight loss rate, as well as the changes in pH, color, and texture of the treated samples, were investigated. The weight of the control and ClO2 gas-treated samples was decreased during the storage period. The change in weight of the control was slightly faster than that of the samples treated with 3 and 4 ppm ClO2 gas. The pH of the control and the ClO2 gas treated samples were decreased during the storage period and there was no significant difference between the control and ClO2 gas treated samples. Concerning color (lightness, redness, and yellowness) changes of Centella asiatica during the storage period, there was no significant difference between the control and ClO2 gas treated samples. The change in shear force in the leaf and stem of Centella asiatica during the storage period was slightly lower in the 4 ppm ClO2 gas treated samples (in the leaf) compared to the control and 3 and 4 ppm ClO2 gas treated samples (in the stem) compared to the control and 5 ppm ClO2 gas treated sample.

As cholesterol intake increases, the prevalence of hypercholesterolemia is also increasing. With increasing food selection considering health, consumption of functional foods that can help health is also expected to increase. Ginger is rich in minerals (such as potassium and magnesium) and antioxidants. Antioxidants have been shown to be effective in lowering blood cholesterol levels. Therefore, we would like to produce madeleines helpful for hypercholesterolemia by adding ginger syrup to madeleines recently consumed as desserts. In this study, the quality and characteristics were analyzed after making madeleine by adding ginger syrup at 0%, 5%, 10%, 15%, and 20%. Baking loss was significantly reduced as the addition amount increased (p<0.001). The pH value decreased as the addition amount increased except for the 5% added group (p<0.001). The b value of the chromaticity showed a significant increase from the 5% addition group (p<0.001). Regarding textures, hardness (p=0.006), gumminess (p=0.001), and chewiness (p=0.001) all decreased as the addition amount increased. Regarding antioxidant activity, polyphenol, DPPH, and ABTS values were significantly increased as addition amount increased (p<0.001). Consequently, Madeleine using ginger syrup rich in antioxidants is expected to help health.

The restraints are used in the intensive care unit as a way to restrict the movement of the whole body or part of the body for the safety of the patient, such as maintaining medical equipment, preventing falls and patient self tube removal through regulating the patient's behavior. However, the physical restraints are used for the physical safety of the patient, but that is cause a variety of physical and psychological complications. Thus, nurses in intensive care units who apply restraint on face an ethical dilemma in the confrontation between the nurse's duty to improve the patient's health and protect the patient's safety and the value of the patient's autonomy and dignity. We have two examples are proposed to identify the ethical dilemma situation faced by nurses, to induce an active attitude towards elimination by establishing exactly restraint - removal criteria. In addition, it is proposed to seek a balance of individual values through active communication between the patient and the medical staff regarding the application of the restraint.

PURPOSES : In this study, the factors affecting the severity of traffic accidents in highway tunnel sections were analyzed. The main lines of the highway and tunnel sections were compared, and factors affecting the severity of accidents were derived for each tunnel section, such as the tunnel access zone and tunnel inner zone. METHODS : An ordered probit model (OPM) was employed to estimate the factors affecting accident severity. The accident grade, which indicates the severity of highway traffic accidents, was set as the dependent variable. In addition, human, environmental, road condition, accident, and tunnel factors were collected and set as independent variables of the model. Marginal effects were examined to analyze how the derived influential factors affected the severity of each accident. RESULTS : As a result of the OPM analysis, accident factors were found to be influential in increasing the seriousness of the accident in all sections. Environmental factors, road conditions, and accident factors were identified as the main influential factors in the tunnel access zone. In contrast, accident and tunnel factors in the tunnel inner zone were found to be the influencing factors. In particular, it was found that serious accidents (A, B) occurred in all sections when a rollover accident occurred. CONCLUSIONS : This study confirmed that the influencing factors and the probability of accident occurrence differed between the tunnel access zone and inner zone. Most importantly, when the vehicle was overturned after the accident occurred, the results of the influencing factors were different. Therefore, the results can be used as a reference for establishing safety management strategies for tunnels or underground roads.

PURPOSES : It is necessary to implement traffic-control strategies for underground roads. In this study, the application criteria for traffic control were developed to minimize actual traffic congestion on underground roads before it occurs. In particular, the traffic congestion judgement criteria and procedure (TJCAP) were developed. They can specifically classify the possibility of traffic congestion underground. METHODS : A microscopic traffic simulation model was used to analyze different scenarios. With the scenario simulation results, a hierarchical clustering analysis was applied to produce quantitative values from the TJCAP for each experimental network case. RESULTS : For network case (a), it was concluded that the possibility of traffic congestion on underground roads increases when the speed of the ground road connected to the main underground road and the connected ground road after the outflow of the ramp section is low. When the connected road is an interrupted facility after entering the underground roads, the red time is long, and when the section travel speed is 15 km/h, the possibility of traffic congestion underground is highest. A cluster analysis based on these results was performed using two techniques (elbow and silhouette) to verify the final classification. CONCLUSIONS : The TJCAP were designed to operate traffic flow with stricter criteria than traffic congestion management on ground roads. This reflects the difference in the driving environment between underground and above-ground roadways.

Hepatic diseases are divided into two types: alcoholic and non-alcoholic. Non-alcoholic liver injury finally induces fatty liver and damages liver function. Many studies have demonstrated that Ecklonia stolonifera has antioxidative, antiinflammatory, and hepatoprotective activities. We conducted a 12-week double-blind, placebo-controlled, randomized trial to examine the efficacy of E. stolonifera extracts (ESE) on biochemical markers of hepatic function. Sixty-five subjects with mild or moderate liver injuries were randomly allocated to receive either 420 mg/d of ESE or a placebo for 12 weeks. Fifty-five participants completed the trial. No significant adverse events were observed among the subjects during the study. The primary end points were changes in plasma levels of aspartate transaminase (AST), alanine transaminase (ALT), and γ-glutamyltransferase (γ-GT). The secondary end points were changes in lipid profile levels, including total cholesterol (TC), triglyceride (TG), highdensity lipoprotein cholesterol (HDL), and low-density lipoprotein cholesterol (LDL). Compared with the baseline, AST and ALT levels decreased significantly in the ESE group compared to those in the placebo group (P<0.001). In addition, γ-GT levels in the ESE group were significantly lower than those in the placebo group (P=0.016). There were no differences in the TC, TG, HDL, and LDL levels between groups. In conclusion, ESE consumption for 12 weeks improved liver parameters in subjects with liver injury. Regular consumption of ESE could maintain liver health in individuals at risk of hepatic damage.

본 연구에서는 3D 프린팅 FDM 방식의 적층 방향에 따라 기계적 물성이 달라지는 이방성 특성을 확인하고 이를 이용하여 위상 최 적설계를 수행하였다. 벤치마크 문제인 자동차 현가장치 부품 중 하나인 로어 컨트롤 암에 대하여 밀도법 기반 위상 최적설계를 수행 하였으며, 외부 하중과 이방성 특성에 따라 위상 최적결과가 다르게 나타나는 것을 확인하였다. 이를 이용하여 최적화된 모델에 대하 여 3D 프린터로 적층 방향을 달리하여 2가지 시험품을 제작하였으며 인장시험을 수행하였다. 시험시 3D 비접촉 변형률 측정기를 이 용하여 변형률을 구하였으며 이를 CAE 응답해석으로 얻은 변형률과 비교한 결과가 정량 및 정성적으로 일치하는 것을 확인하였다. 3D 프린팅 적층 방향을 고려한 위상 최적모델의 인장 실험 결과를 통해 해당 최적설계 방법론의 유효성을 검증하였다.

The fish community in the Seomjin River-Seomjin River Estuary-Gwangyang Bay coast continuum was investigated three times from March 2019 to October 2019. The collected species at the eight sites during the survey period were 49 species belonging to 31 families, including two endangered species. According to Bray-Curtis similarities, observations were divided into four groups based on the fish community composition; two groups (group 1, 2) and two uncategorized groups (group 3, 4). ANOSIM based on spatial and temporal groupings indicated that the spatial differences in fish communities (R=0.398, P=0.001) were relatively more important than the temporal differences (analysis of similarities, R=0.273, P=0.002). In particular, there were significant differences between groups 1 and 2 (analysis of similarities, R=0.556, P=0.001), and similarity percentage analysis revealed that Argyrosomus argentatus (9.4%), Favonigobius gymnauchen (6.9%) and Konosirus punctatus (5.9%) contributed to these differences of fish assemblages for each group. The fish fauna distributed in the Seomjin River-Gwangyang Bay ecosystem were spatially divided and the number of species and number of individuals showed seasonal differences. This study could be a basis for understanding changes in the fish community and implementing conservation and management strategies on major species within a continuous environment of the river-estuary-ocean continuum.