High nickel content Li(NixCoyMn1-x-y)O2 (NCM, x ≥ 0.9) cathode materials suffer from rapid capacity fading, a significant obstacle to their commercial application. To mitigate this issue, strategies such as doping and coating with various elements have been widely reported. In particular, multi-element doping has been explored as a potentially more effective alternative to single or dual element modification. Concurrently, the synthesis of high-entropy precursors via coprecipitation has gained significant attention. In this study, high nickel content precursors with nine components were synthesized by hydroxide coprecipitation under varying concentrations of ammonia that was employed as a chelating agent. The primary particle morphology of the precursors was found to be dependent on the ammonia concentration, which in turn influenced the physicochemical and electrochemical properties of the final cathode materials. At low ammonia concentration, the formation of secondary phases was detected. Notably, the cathode synthesized under high ammonia concentration exhibited excellent cycling stability, delivering a discharge capacity of 164.22 mAh/g after 100 cycles at 1 C, which corresponds to a capacity retention of approximately 91 % of its initial discharge capacity (180.50 mAh/g at 0.1 C).

The 30mm wheel type anti-aircraft gun replaces the aging anti-aircraft gun in the front and is a weapon system for local anti-aircraft defense against enemy aircraft and small unmanned vehicles. In the field, damage to the turret hatch/closed hatch pin occurred between the operation of the wheel type anti-aircraft gun. As a result of the sem analysis of the hatch pin fracture surface, it appears that brittleness fracture occurred and fatigue fracture occurred at the final fracture surface while reaching the fatigue strength by repetitive loads. The hatch angle fixing pin and bracket shapes were changed to disperse the stress concentration. As a result of checking the location of the vulnerable area of the hatch pin and the shear stress value through structural analysis, the safety factor improved from 1.46 to 2.95 after improvement. Through this study, it is expected to be used as a reference material for failure analysis and design plan for the existing system in the future.

본 연구는 도로변 완충녹지에서 녹지구조와 공기 중 미세먼지 농도(지상 1.5m 지점)를 조사하여 미세먼지 농도에 영향을 주는 완충녹지의 구조적 요인을 파악하고자 하였다. 총 10개소의 완충녹지에서 측정된 미세먼지 농도를 도로측 미세먼 지 농도와 비교한 상대농도지수(Relative PM10 Index: RPM10)를 산출하였다. RPM10이 양의 값이면 녹지의 농도가 더 낮고, 음의 값이면 녹지의 농도가 더 높음을 의미한다. 미세먼지 농도 측정 결과 도로측과 비교하여 녹지측의 미세먼지 농도가 전반적으로 높았다. 녹지구조 변수와 상관분석 결과 RPM10은 관목층 피도, 전체 수목 피도, ㎡당 관목층 체적과 양의 상관성이 유의하였고, 평균 수고, 지하고, 식재 밀도, 교목층의 피도와 ㎡당 체적 등은 유의한 상관성을 확인할 수 없었다. 또한 완충녹지 배후공간이 막혀있는 곳의 RPM10이 비어있는 곳보다 낮은 차이가 인정되었 다. 회귀분석 결과 완충녹지 배후공간이 막힌 곳에서는 빈 곳보다 RPM10이 낮아지고(B=-.123, P=.000), 관목층 체적 (B=.674, P=.004)과 수목 지하고(B=.072, P=.015)가 증가하면 RPM10이 높아지는 것으로 파악되었다. 완충녹지에서 측정된 더 높은 미세먼지 농도는 녹지에서 미세먼지가 차단·정체된 결과로 판단된다. 정체된 미세먼지는 녹지 내부에서 제거되어 외부 미세먼지 농도 감소에 기여한다. 분석결과 관목층 식재 및 지하고가 낮은 교목·아교목층 수목의 배치는 미세먼지의 흐름 차단에 유리한 것으로 나타났다. 이러한 결과는 향후 도로변 완충녹지 조성뿐만 아니라 도시공원·녹지 계획의 수립 시 미세먼지 저감을 위한 식재 전략으로 고려될 수 있다.

This study evaluated the effects of a high-concentration soy pulp (HSP) diet on pig production performance and carcass traits under commercial farming conditions. Data were collected from a pig farm in Jeju, Korea, between 2019 and 2024. From 2019 to 2021, pigs were fed a control diet containing 2.3% soy pulp, and from 2022 to 2024, the proportion of soy pulp was increased by 254% (HSP, 21.9%). We evaluated production performance indicators including shipment date, feed cost per kilogram of weight gain, feed conversion ratio, carcass weight, carcass yield, and proportion of high-grade carcasses. The feed cost per kilogram remained constant under both diet conditions; however, pigs fed an HSP diet reached market weight significantly earlier than those on the control diet and the feed conversion ratio, carcass weight, and proportion of high-grade carcasses were significantly improved. The carcass yield percentage was non-significantly higher for pigs fed the HSP diet than for those fed the control diet. These findings suggest that providing HSP feed to grow–finish pigs enhance growth performance, improves carcass quality, and shortens the production period, indirectly reducing feed costs. Further studies should explore the long-term economic impacts and potential interactions of HSP with gut health and nutrient digestibility.

Graphene, mechanically exfoliated as a single-atom-thick two-dimensional (2D) material, is renowned for its exceptional carrier mobility and mechanical strength, making it a highly promising material for a wide range of applications; however, following the synthesis of large-area, high-quality graphene, quality degradation, such as tearing, frequently occurs during the transfer process. Currently, chemical vapor deposition (CVD) enables reliable synthesis of large-area graphene, and both wet and dry transfer methods are widely employed to transfer graphene onto various substrates. This study focuses on the wet transfer method to improve transfer efficiency by optimizing the interfacial adhesion among graphene, the polymethyl methacrylate (PMMA) support layer, and the target substrate. To enhance the efficiency of the wet transfer process, the PMMA concentration and ultraviolet ozone (UVO) treatment time were systematically optimized. As a result, a transfer yield of up to 97.16 % was achieved under optimized conditions consisting of 6 % PMMA concentration and 15 min of UVO exposure. This research contributes to the development of highly efficient graphene transfer techniques, which are crucial for reducing production costs and processing time in a wide range of advanced applications such as electronics, energy storage, biomedical devices, environmental monitoring, and materials science.

This study utilized real-time particulate matter (PM10) monitoring equipment mounted on vehicles and drones to measure PM10 concentrations in industrial complexes and track potential emission sources. This research was conducted in four industrial complexes located in Gyeonggi Province and Incheon Metropolitan City (Hwaseong Songsan Technopark, Incheon Geomdan, Incheon Namdong, and Hwaseong Mado) from August to October 2022, with a total of five measurement sessions. A vehicle-mounted light-scattering PM-monitoring device, Sniffer4D, was used to measure PM10 concentrations across the industrial complexes, followed by additional drone-based measurements in high-concentration areas. The results revealed significant variations in PM10 concentrations across different industrial complexes, ranging from an average of 10.3 mg/m3 to 51.6 mg/m3. In certain areas, PM10 levels exceeded the air quality threshold for poor conditions (80 mg/m3). Notably, in the high-concentration areas of Namdong and Mado Industrial Complexes, where PM10 exceeded the threshold, elevated measurements were observed at altitudes of 25~40 m, with concentrations reaching 164.4 mg/m3 and 189.0 mg/m3, respectively. These findings suggest that PM10 emissions from industrial facilities may be more concentrated at specific altitudes rather than at ground level. This study demonstrated that conventional ground-based monitoring alone has limitations in accurately identifying emission sources and that three-dimensional drone-based measurements provide a more effective approach for emission source tracking.

Environmental DNA (eDNA) has emerged as a promising tool for aquatic biodiversity monitoring, yet its collection in lentic ecosystems remains technically constrained by filtration capacity and field logistics. In this study, we applied a novel eDNA concentration system, QuickConcTM, to evaluate freshwater mussel diversity in lakes, and compared its performance with the conventional GF/F filtration method. Water samples were collected from four reservoirs at surface, mid, bottom, and waterside layers, and processed using both filtration techniques. Metabarcoding of mitochondrial 16S rDNA revealed that QuickConcTM captured a higher average number of amplicon sequence variants (ASVs) and exhibited greater species richness and diversity indices (Shannon and Simpson), although the differences were not statistically significant. QuickConcTM samples showed a greater capacity to detect rare taxa and to recover higher ASV richness in certain cases, suggesting its potential to enhance biodiversity resolution. Species composition remained consistent across methods, with Cristaria plicata and Sinanodonta lauta being dominant in both cases. However, slight spatial variations in species assemblages were observed between center and waterside sampling points, highlighting the influence of habitat heterogeneity on eDNA distribution. Overall, our results demonstrate that the QuickConcTM system offers a practical and efficient alternative to traditional filtration methods for eDNA-based freshwater mussel monitoring, particularly in environments with high suspended solids. The findings underline the need for adaptive sampling strategies that consider both methodological and ecological factors when designing eDNA surveys in lentic ecosystems.

This study investigates the acute toxicity of sublethal tributyltin (TBT) exposure in the marine polychaetes Perinereis aibuhitensis by measuring changes in mortality, burrowing activity, acetylcholinesterase (AChE) function, and antioxidant defense mechanisms. The 96h-LC50 of TBT was established at 23.7 μg L⁻¹. Following exposure to 1 μg L⁻¹ of TBT led to a dose-dependent reduction in burrowing behavior and AChE activity in polychaetes. Elevated levels of malondialdehyde (MDA) and pronounced reduction of glutathione (GSH) contents explained significant oxidative stress. The major antioxidant enzymes, including GSH peroxidase, GSH reductase, catalase, and superoxide dismutase, were also significantly suppressed following TBT exposure. These findings indicate that TBT-induced acute toxicity compromises physiological functions and undermines antioxidant defense system in polychates.

Concentration-dependent multicolor emission is an unusual yet appealing photoluminescence property of various carbonaceous nanomaterials with interesting potential applications. While carbon dots (CDs) are no exception, the predictability and tuning of the microenvironment of CD to make it suitable for displaying concentration-dependent multicolor emission is far from adequately understood. Through the novel synthesis of bromine-doped CDs (Br-CDs) via controlled hydrothermal pyrolysis, we demonstrate the capacity of the same Br-CD to emit intense red (650 nm) as well as blue fluorescence (410 nm) including intermittent colors as a function of concentration and excitation wavelength. The concentration-dependent morphological transition of the Br-CDs was ascertained using electron microscopy shedding light on their optical evolution in response to concentration changes. The phenomenon is validated as being driven by unique rearrangement and surface functionality modulation, which is essentially linked to the concentration of CD in an ensemble. Notably, the synthesized Br-CDs displayed excellent enzyme-mimicking abilities where oxidase-like activity was assessed using a tetramethylbenzidine (TMB) substrate under visible light (LED, 23W), and peroxidase-like activity was evaluated with TMB and H2O2 over a wide range of pH and temperature. The visible-light-triggered generation of Reactive Oxygen Species (ROS) by Br-CDs proved to be an effective antibacterial agent demonstrating a significant eradication rate against both Gram-positive and Gramnegative bacteria. A captivating and unusual photophysical phenomenon is exhibited by Br-CD, showcasing their versatile applications in nanozymes and antibacterial interventions where emission color directly links to the activity eliminating the necessity of multiple titrations to determine concentration/units/dosage.

When manufacturing a square plate with a pinhole, the following conclusions were obtained as a result of analyzing the effect of changes in the size of the grid filling the inside of the plate and the presence or absence of a pinhole on the stress concentration factors. 1. It can be seen that in the case where there is a pinhole, the overall stress concentration factors is twice as high as in the case where there is no pinhole. In addition, in the case where there is no pinhole, it can be seen that the stress concentration factors fluctuates at a certain standard depending on the position of the pinhole and the internal grid, and in the case where there is a pinhole, it decreases at a certain point and then increases again. 2. In the case where there is no pinhole, when the L/H ratio increases from 0.1 to 0.3, the Kt value increases from 1.8 to 2.7, an increase rate of approximately 50%. Similarly, in the case of a pinhole, when the L/H ratio increases from 0.1 to 0.4, the Kt value increases from 2.0 to 3.0, an increase rate of about 50%.

본 연구는 솎아베기 후 3년이 경과한 동일 연령(27년생)의 서로 인접한 지역에 식재된 삼나무와 편백 조림지를 대상으로 임상과 광물질 토양층의 양분 농도 및 저장량 변화를 조사하였다. 솎아베기 실시에 따라 삼나무 조림지의 임상은 인의 양분 농도와 저장량이 대조구에 비해 높았으나, 편백 조림지는 칼륨과 마그네슘 농도와 저장량이 대조구에 비해 낮게 나타났다. 삼나무 조림지의 토양 0∼10cm 깊이에 질소와 칼륨 농도, 편백 조림지의 10∼20cm 깊이의 인 농도는 대조구에 비해 낮아 솎아베기에 따른 양분 반응이 수종과 깊이에 따라 차이가 있었다. 솎아베기구의 양분 저장량은 삼나무 조림지가 0∼10cm 깊이에서 칼륨 저장량, 편백 조림지는 10∼20cm 깊이에서 인 저장량이 대조구에 비해 낮은 값을 보였다. 본 연구 결과에 따르면 삼나무와 편백 조림지는 솎아베기 후 질소, 인, 칼륨의 농도나 저장량이 대조구에 비해 낮게 나타나 잔존 임목들의 생육 촉진을 위해서는 이들 양분에 대한 시비와 같은 토양 양분관리를 고려해야 하는 것으로 나타났다.

본 연구에서는 인쇄 회로 열교환기 채널에서의 응력 집중 해석을 수행하였다. 응력 집중이 발생하는 응력 집중부의 응력을 도출하 기 위해 전체 시스템의 해석 결과를 활용하는 부모델링 기법을 사용하였다. 미세한 기하학적 형상과 비가역적 소성 변형을 고려한 부 모델의 탄성 및 소성 해석을 수행하였다. 탄성 및 소성 해석에서 얻은 응력을 통해 미세한 기하학적 형상이 PCHE의 응력 분포에 미치 는 영향을 파악하였다. 탄성 해석과 소성 해석에서의 최대 폰 미제스 응력을 비교하여 응력 집중부의 응력 집중 경향과 소성 변형을 확인하였다.

This study was conducted through experiments by producing an image output evacuation guide light linked with a smoke detector. To summarize the results, first, the biggest recognition distance of the door at 30% smoke concentration was found to be the image output evacuation guide light. This is because of visual impairment and fear caused by indoor smoke, and in the process of finding the light of the emergency exit, accurate recognition of the evacuation behavior was searched even at the farthest distance, and it is judged that the time required for evacuation was short. Second, the biggest recognition distance of the door at 70% smoke concentration was the image output evacuation guide light, which showed the longest recognition distance. It is judged that even in smoke with many evacuees, the door is accurately recognized while seeing the light of the image output evacuation guide light and exits safely. Third, when the smoke concentration was 100%, the smoke rose and the evacuation guide light at the top of the door was not identified as thick smoke, and the image output evacuation guide light was displayed on the bottom of the passage, indicating that the evacuee accurately recognized the door and escaped safely to the outside even from a long distance.

In this study, when manufacturing a rectangular plate with a pinhole, the following conclusions were obtained as a result of analyzing the shape characteristics of the unit cell that fills the interior of the plate and the effect of changes in the size of the pinhole on the stress concentration coefficient. 1. The stress value generated in the case of the completely empty model was 13.9 MPa, which is an 18.8% increase in stress compared to the stress value 11.7 MPa generated in the fully filled model. However, since the weight of the empty model is 43.6% lower than that of the filled model, it is believed to be very advantageous in terms of cost. 2. The stress concentration coefficient value is lowest for the solid model and highest for the hollow model at the same d/H value. In other words, you can see that the values are changing within the boxes of the solid model and hollow model. However, the grid matching model is closest to the solid model and the filling rate is as low as 33.4-9.1%, showing the most stable strength when filling empty space.