PURPOSES : Demonstrated performance degradation of LiDAR for vehicle and pedestrian dummy in rainy and foggy road conditions. METHODS : In real-scale rain and fog road conditions, adjust the distance between LiDAR and the measurement target from 10m to 70m (in 10m interval), measure LiDAR NPC (number of point cloud) and intensity, and compare the resulting numerical values. RESULTS : LiDAR's NPC and Intensity showed statistically significant differences by overall weather condition (normal, rain, fog), and the values were found to be larger in the order of normal>rainfall>fog. In the case of vehicles, sunder rain conditions, NPC and intensity are recognized even at 70m as in normal conditions, but under fog conditions, NPC and intensity are measured only up to 30m. In the case of pedestrians, the reflective area size is smaller than that of vehicles, so they are recognized only up to 30m in rainy conditions, and NPC and intensity are measured only up to 20m in fog conditions. CONCLUSIONS : It was confirmed that LiDAR performance deteriorates in rain and fog compared to normal.

본 연구에서는 에너지 소모가 큰 기존 진공 증류 공정의 대안으로 친환경이면서 에너지 효율적인 투과증발 분리 공정을 이용하여 1,2 hexane diol/water (1,2 HDO/water) 혼합물에서 물을 분리하는 데 적용되었다. 사용한 분리막은 glutaraldehyde (GA)로 가교된 PVA를 알루미나 중공사 막(Al-HF) 내부에 코팅하여 사용하였다. 1,2 HDO/water 투과증발 분리공 정에서는 PVA/GA 비율, 경화 온도 및 투과증발 분리공정 운전 조건에 대한 막의 최적화를 연구하였다. 장기 안정성 시험에 서 PVA/GA (몰 비율 = 0.08, 경화 온도 = 80°C) 로 코팅된 Al-HF 막이 공정온도 40°C에서 1.90~2.16 kg/m2h 범위의 투과 도를 보였으며, 투과용액의 수분 함량은 99.5% (separation factor = 68) 이상이었다.

이 연구 논문은 기후 변화에 대한 전 세계적인 우려와 온실 가스 배출 감소를 위한 필수적인 요구에 대응하여 마 이크로기공 고분자(PIM-1)의 이용을 탐구한 것이다. 연구는 PIM-1 막을 이산화탄소(CO2) 가스 분리 막으로 사용하는 현대적 인 소재로서의 응용에 집중하고 있다. 연구는 PIM-1 막의 합성, 분자량 제어, 그리고 제각각의 특성 분석 기술을 통해 포괄적 인 통찰을 제공하며, 이러한 특성 분석 기술을 통해 PIM-1의 고유한 교차결합 및 강성 구조에서 비롯된 내재적 다공성이 특 히 이산화탄소의 선택적 투과에 활용되고 있다. 논문은 PIM-1의 가교된 구조로부터 비롯된 내재적 다공성이 특히 이산화탄 소의 선택적 투과에 활용되고 있다. 논문은 PIM-1의 튜닝 가능한 화학적 특성을 강조하며, 가스 분리 막의 맞춤 및 최적화를 가능케 하는 특성에 대한 이해를 제시하고 있다. 분자량을 통제함으로써 고분자량(H-PIM-1) 막은 낮은 분자량 대비 더 뛰어 난 CO2 투과성과 선택성을 나타내며, 이를 통해 PIM-1 막의 특성을 조절하는 데 분자량의 중요성을 강조하고 있다. 연구 결 과는 PIM-1 막 특성을 조절하는 데 분자량이 중요한 역할을 하는 것을 강조하며, 이는 기후 변화의 긴급한 글로벌 도전에 대 응하기 위한 효율적이고 선택적인 CO2 포집을 위한 차세대 막 기술의 발전에 기여하고 있다.

PURPOSES : This study is to develop an comprehensive validation methodology for autonomous mobility-on-demand system with level 4 automated driving system. METHODS : The proposed method includes the quantitative techniques for validating both automated driving system and center system using each optimal indicators. In addition, a novel method for validating the whole system applying multi-criteria decision methodology is suggested. RESULTS : The relative weights for the vehicle system was higher than the center systems. Moreover, the relative weights of failure rate for validating the vehicle system was the highest, in addition to, a relative weight for accuracy of dynamic routing algorithm within center system was the highest. CONCLUSIONS : The proposed methodology will be applicable to validate the autonomous mobility on demand system quantitatively considering the relative weights for each systems.

Water utilities are making various efforts to reduce water losses from water networks, and an essential part of them is to recognize the moment when a pipe burst occurs during operation quickly. Several physics-based methods and data-driven analysis are applied using real-time flow and pressure data measured through a SCADA system or smart meters, and methodologies based on machining learning are currently widely studied. Water utilities should apply various approaches together to increase pipe burst detection. The most intuitive and explainable water balance method and its procedure were presented in this study, and the applicability and detection performance were evaluated by applying this approach to water supply pipelines. Based on these results, water utilities can establish a mass balance-based pipe burst detection system, give a guideline for installing new flow meters, and set the detection parameters with expected performance. The performance of the water balance analysis method is affected by the water network operation conditions, the characteristics of the installed flow meter, and event data, so there is a limit to the general use of the results in all sites. Therefore, water utilities should accumulate experience by applying the water balance method in more fields.

Membrane bioreactor (MBR) provides the benefits on high effluent quality and construction cost without the secondary clarification. Despite of these advantages, fouling, which clogs the pore in membrane modules, affects the membrane life span and effluent quality. Studies on the laboratory scale MBR were focused on the control of particulate fouling, organic fouling and inorganic fouling. However, less studies were focused on the control of biofouling and microbial aspect of membrane. In the full scale operation, most MBR produces high effluent quality to meet the national permit of discharge regulation. In this study, the performance and microbial community analysis were investigated in two MBRs. As the results, the performance of organic removal, nitrogen removal, and phosphorus removal was similar both MBRs. Microbial community analysis, however, showed that Azonexus sp. and Propionivibrio sp. contributed to indirect fouling to cause the chemical cleaning in the DX MBR.

이온교환막은 전기막 공정의 성능을 결정하는 핵심 구성 요소이다. 본 총설에서는 다양한 전기막 공정에 적용되 는 이온교환막의 성능을 탄소계 및 금속계 나노물질을 이용한 개질을 통해 향상시킨 최신 연구 동향을 살펴보았다. 나노물질 들은 다양한 방법을 통해 이온교환막에 도입될 수 있다. 특히 탄소계 나노물질은 화학적 개질을 통해 추가적인 기능기를 도 입함으로써 고분자 사슬과의 상호작용을 강화할 수 있다. 이를 통해 이온교환막의 이온전도도를 개선시킬 수 있을 뿐만 아니 라 적층 구조를 통한 체거름 현상으로 이온 선택 투과성을 향상시킬 수 있다. 한편, 금속계 나노물질은 적층 구조 혹은 다공 성 구조를 갖는 특성을 이용하여 이온교환막 내에서 목적 이온과 배제 이온 간의 수화 반경 차이를 이용한 체거름 특성을 통 해 이온 선택 투과성을 향상시킬 수 있다. 또한, 사용한 바인더의 특성에 따라서는 나노물질-바인더 간의 상호작용을 통해 이 온전도도도 향상시킬 수 있다. 본 총설로부터 탄소계 및 금속계 나노물질을 이용하여 이온교환막의 특성을 효과적으로 조절 할 수 있으며, 따라서 이에 관한 연구가 전기막 공정의 성능을 크게 향상시키기 위해 중요함을 확인할 수 있다.

As a means to activate eco pastoral system in alpine grassland, the government can consider public pastures, which are currently unused, to scale them up into public ranches. Depending on ownership and operation, four management models proposed as follows: 1) Government-Owned and Operated with Balanced Profit and Loss 2) Government-Owned and Operated with Revenue Generation 3) Government-Owned but Privately Operated by Outsourced to Professional Manager 4) Full Privatization (Ownership and Operation by Private Individuals). The study outlined above proposes four management models for the activation of eco pastoral system in alpine grassland. It also suggests methods for the selection and performance evaluation of manager to establish a profitable structure. Additionally, the research provides management methods for the conservation of grazing ecology in pastoral ecosystems. Particularly, the adaptation of tools commonly used in South Korean business sector for the selection and performance evaluation of manager within the system of the proposed management models. This aspect is deemed valuable as it aligns these tools with the specific characteristics of eco pastoral system in alpine grassland, contributing not only to the effective implementation of the models but also to the enhancement of the revenue structure.

PURPOSES : The purpose of this paper is to evaluate the performance of MAST composite pavement. METHODS : A Testbed with three different sections with varying pavement materials were constructed: Section 1 (MAST(Multi-Layered Asphalt Surface Treatment) Composite Pavement; RCC(Roller Compacted Concrete)+Modified DBST(Double Bituminous Surface Treatment), Section 2 (Aggregate base+Modified DBST), and Section 3 (aggregate base+General DBST). The structural stability and skid resistance were evaluated using LFWD test and sand patch test, respectively. Moreover, laboratory specimens of four different pavement materials (HMA(Hot Mix Asphalt), Gravel base+DBST, RCC+DBST, and RCC+Modified DBST) were fabricated using and the rutting resistance of each pavement type was evaluated using the MMLS3. RESULTS : As a result of the LFWD(Light Falling Weight Deflectometer) test, the elastic modulus of Section 1 was significantly higher compared to the other section with values between 450 MPa to 650 MPa. Meanwhile, the elastic modulus of Section 2 and Section 3 were almost similar from 50 MPa to 150 MPa. Moreover, sand patch test results showed that Section 1 and Section 2 have an excellent surface roughness with values higher than 0.7 mm but Section 3 has a poor surface roughness with MTD(Mean Texture Depth) value of 0.4 mm. Lastly, based on the results of the MMLS3(third scale Model Mobile Load Simulator) test, gravel base+DBST showed the lowest resistance to rutting among the four specimens, and both RCC+modified DBST and RCC+DBST showed good performance up to 600 loading cycles, but the rut depth increased rapidly until 1,000 loading cycles. CONCLUSIONS : MAST composite pavement(RCC+modified DBST) has superior structural stability compared to general DBST pavement (aggregate base+DBST), has excellent skid resistance with values higher than 0.7 mm, and has similar rutting resistance to that of general dense asphalt concrete pavement. Therefore, exhibiting its good performance in both structural and functional aspects, it can be concluded that MAST composite pavement(RCC+modified DBST) can be an effective alternative for pavement material in Southeast Asian developing countries where support for heavy vehicle loads is required and rutting is likely to occur.

PURPOSES : In this study, the basis for improving the maintenance method of road pavement in Jeju Island, where deterioration is accelerating, was presented through field construction and analysis of various combinations of maintenance methods. METHODS : Construction was performed on Jeju Island's Aejo Road, which has high traffic and frequent early damage, using various asphalt mixtures mainly applied in Jeju Island, with different maintenance cross-sections depending on the level of repair. The quality and performance of the asphalt mixture collected during construction were evaluated, and MEPDG was used to analyze the service life according to the type and maintenance level of the mixture. RESULTS : While the mixture for the surface layer satisfied the quality standards and had excellent rutting and moisture resistance performance, the asphalt mixture for the intermediate and base layer did not satisfy the quality standards such as air voids, so it was judged that quality control was necessary during production. The section repaired to the base layer was found to be advantageous for the integrated behavior of the pavement and had the best structural integrity. As a result of predicting the service life, the estimated life of the section where only the surface layer was repaired was analyzed to be approximately 7 years, the section where the intermediate layer was repaired was 14.5 years, and the section where the entire section up to the base layer was repaired was analyzed to be 18 years. CONCLUSIONS : In Jeju Island, where deterioration is accelerating, it was analyzed that when establishing a maintenance plan, it is necessary to consider repairing the middle and base floors in order to secure the designed life of 10 years.

PURPOSES : The purpose of this study is to provide basic data to improve the service life of asphalt pavement using basalt aggregate in Jeju Island by evaluating the performance of asphalt pavement through analysis of material and structural aspects. METHODS : To evaluate the performance of Jeju Island's asphalt pavement, cracks, permanent deformation, and longitudinal roughness were analyzed for the Aejo-ro road, which has high traffic and frequent premature damage. Cores were collected from Aejo-ro sections in good condition and damaged condition, and the physical properties of each layer were compared and analyzed. In addition, plate cores were collected from two sections with severe damage and the cause of pavement damage was analyzed in detail. RESULTS : About 45% of the collected cores suffered damage such as layer separation and damage to the lower layer. The asphalt content of surface layer in the damaged section was found to be 1.1% lower on average than that in the good condition section, and the mix gradations generally satisfied the standards. The density difference between the cores of each layer was found to be quite large, and the air voids was found to be at a high level. CONCLUSIONS : Test results on the cores showed that, considering the high absorption ratio of basalt aggregate, the asphalt content was generally low, and the high air voids of the pavement was believed to have had a significant impact on damage. High air voids in asphalt pavement can be caused by poor mixture itself, poor construction management, or a combination of the two factors. Additionally, the separation of each layer is believed to be the cause of premature failure of asphalt pavement.

PURPOSES : This study was conducted to evaluate the physical properties of the RAP 50 asphalt mixture containing polymer modified rejuvenator and warm-mix additive to improve the recycling rate of RAP and reduce CO2 emission. METHODS : Mix design of Polymer Modified Warm-mix Asphalt Mixture(RAP 50), and Hot Mix Asphalt Mixture(RAP 30) were produced and the properties of asphalt mixture such as Marshall Stability, ITS, Deformation Strength, TSR, and Dynamic Stability were compared between the two asphalt mixtures. RESULTS : The RAP 50 asphalt mixture showed superior or similar performances compared to the RAP 30 asphalt mixture in all the tests conducted. The results of the Marshall stability and dynamic stability in particular were 13,045N and 3,826 pass/mm, which were 11.37% and 76.7% greater than the RAP 30 asphalt mixture, which indicated that high plastic deformation resistance may be expected. CONCLUSIONS : The results obtained from laboratory tests on the two types of mixtures indicated that the use of polymer modified rejuvenator and warm-mix additive not only allows to increase the proportion of RAP but also improves its properties under lower temperature condition than RAP 30 asphalt mixture. Additionally, it was confirmed that plastic deformation resistance was high and moisture resistance and crack resistance were improved for a RAP 50 asphalt mixture.

γ-aminobutyric acid (GABA) is a natural stress-reducing substance and is actively used as a human health supplement. However, minimal research has been conducted on its use in cattle. This study was conducted to evaluate the effects of GABA on the growth performance, complete blood count, blood metabolites, and carcass characteristics of fattening Hanwoo steers. Twenty-one fattening steers were randomly assigned to one of three treatments: control (basal diet: concentrate feed + rice straw), T1 (basal diet + GABA supplement at 0.8% of feed/head/day), and T2 (basal diet + GABA supplement at 1.6% of feed/head/day). Feed intake and conversion ratio did not differ among the treatments. However, the average daily gain during the early fattening period increased linearly to 0.80 kg, 0.86 kg, and 0.92 kg in the control, T1, and T2 groups (p<0.05). Plasma γ-glutamyl transferase (37.5, 58.2, 42.8 U/ℓ) and creatinine (1.32, 1.34, 1.49 ㎎/㎗) levels in the GABA supplement group were increased compared to those in the control group. The carcass weight (422.7, 427.1, 454.1 kg), rib eye area (86.67, 92.57, 91.14 cm2), and marbling score (3.67, 4.29, 4.14) were numerically higher in the GABA supplement group than in the control group. Thus, GABA supplementation positively affected the average daily gain and carcass characteristics of Hanwoo steers. However, the effect of the GABA supplement level of GABA was small, and further research using rumen-protected coating technology on GABA is necessary.

We aimed to develop and analyze the effectiveness of a “Room of Errors” simulation program for educating nursing students in patient safety management. Methods: This study used a quasi-experimental method (two group, before and after evaluation) and enrolled 35 nursing students as the participants. Data were collected using a self-reported questionnaire and analyzed through descriptive statistics and the independent t-test and Mann-Whitney U test using SPSS/WIN Statistics version 25.0. Results: After completing the “Room of Errors” simulation program, the participants’ score of intention and confidence in performance for patient safety management in the experimental group were significantly higher than those in the control group. Conclusion: A “Room of Errors” simulation education program for nursing students effectively increased the intention and confidence in performance of nursing students in patient safety management.

PURPOSES : The number of snowfall and the amount of snowfall are gradually increasing, and due to the characteristics of Seoul, which has a lot of traffic, it is difficult to respond quickly with a snow removal method that relies on snow removal vehicles. Therefore, it is necessary to develop an IoT based eco-friendly snow removal system that can respond to unexpected heavy snow in winter. In this study, the low temperature operation and snow removal performance of the IoT road condition snow removal detector and the snow removal system using CNT and PCM are evaluated in the climatic environment chamber. METHODS : To make artificial snow, it consists of an climatic environment chamber that can simulate a low temperature environment and equipment that can supply compressed air and cold water. Depending on the usage characteristics of the climatic environment chamber, use an air-water type snow maker. In order to make artificial snow, wet temperature, which takes into account the actual air temperature and the amount of moisture in the air, acts as the most important variable and is suitable for making snow, below –1.5 ℃. The lower the water temperature, the easier it is to freeze, so the water source was continuously supplied at 0 ℃ to 4 ℃. One of the two different pipes is connected to the water tank to supply water, and the other pipe is connected to the compressor to supply high-pressure air. Water is dispersed by compressed air in the form of many small droplets. The sprayed microscopic water particles freeze quickly in the low temperature environmental climatic chamber air and naturally fall to the floor, forming snow. Based on the KS C IEC 60068-2-1 cold resistance test standard, an integrated environmental test procedure was prepared to apply to IoT-based snow removal systems and performance evaluation was performed accordingly. The IoT based eco-friendly snow removal system is needed to in winter, so visual check and inspect the operation at the climatic chamber before setting up it to the actual site. In addition, grid type equipment was manufactured for consistent and reliable snow removal performance evaluation under controlled environmental conditions. RESULTS : The IoT-based eco-friendly snow removal system normally carried out the task of acquiring data and images without damaging the appearance or freezing in a low temperature environment. It showed clear snow removal performance in areas where PCM and CNT heating technology were applied to the concrete slab. This experiment shows that normal snow removal tasks can be carried out in low temperature environments in winter. CONCLUSIONS : The integrated environmental test procedures and grid type evaluation equipment are applied to low temperature operation and snow removal performance evaluation of snow removal systems. In the climatic environment chamber, where low temperature environments can be simulated, artificial snow is created regardless of the season to derive quantitative experimental results on snow removal performance. PCM and CNT heating technology showed high snow removal performance. The system is expected to be applied to road site situations to preemptively respond to unexpected heavy snow in winter.

The purpose of this study is to propose measures to increase evacuation safety by calculating the habitable time using a fire and evacuation simulation program for the Room-escape cafe currently in operation, and comparing and analyzing it with the evacuation required time. Assuming a fire due to overheating of electric heaters in use in front of the warehouse, the habitable time was calculated through fire simulation, and the occupant's evacuation time calculated through evacuation simulation according installation of safety facilities, etc. was compared and analyzed with the habitable time. In the case of escape room cafes with safety facilities installed, evacuation safety was satisfied, but in escape room cafes without safety facilities, the evacuation safety was not secure. As a result of analyzing evacuation safety for each scenario based on the ASET analyzed in the fire simulation, it was found that in scenario 1, evacuation safety was secured and everyone successfully evacuated, while in scenario 2, no one succeeded in evacuation. These results can be said to confirm that the installation of safety facilities is very important in business establishments such as escape room cafes, which become enclosed structures when games are started.

본 연구는 일반농산어촌개발사업의 사업내용 중 하나인 농촌중심지활성화사업으로 준공에 이른 농촌 커뮤니티 시설의 주민조직 직접 운영에 따른 운영성과와 농촌 커뮤니티 시설에 미치는 영향요인을 분석 하여 문제점을 도출하고 개선방안을 제시하는데 목적을 두고 있다. 또한 전라북도 농촌중심지활성화사 업으로 준공에 이른 농촌 커뮤니티 시설 중 주민조직에 의해 운영되고 예산이 비슷하며, 비교가 가능한 부안군 보안면, 김제시 금구면, 임실군 강진면을 대상으로 연구를 진행하였다. 설문지는 배포 후 회수하는 방법으로 수집하였으며, 일반현황과 독립변수의 측정지표에 근거한 리커트 7점 척도를 통해 분석한 결과는 다음과 같다. 설문결과는 설문에 대한 응답자의 일반현황, 빈도, 백분율 분석, 측정 문항의 신뢰 도 분석을 위해 크론바흐의 알파 값 계수법 분석, 세부 측정지표별 설문조사 분석, 연구가설 검증을 위한 다중회귀분석, 세부 운영성과의 차이를 분석하기 위한 일원배치 분산분석과 사후검정을 실시하였다. 연구가설과 리커트 7점 척도를 통한 연구의 결론은 측정문항의 신뢰성이 인정되었으며, 농촌 커뮤니티 시설의 주민조직 직접 운영은 시설의 운영성과에 영향을 미치고 있다. 성공적인 운영과 운영성과를 제 고 및 개선하기 위해서는 다양한 계층들의 이용에 있어 편리하도록 환경관리 및 시설의 설비에 최선의 노력을 기울여야 한다. 또한 시설 운영의 주체인 주민조직의 기능을 강화하여 지역의 공동체 교류공간 이 되도록 주민조직과 지역주민이 직접 관심을 가지고 참여하여 주민조직만의 공간을 확보하는 것이 중요하다. 이 연구를 통해 시설의 편리성과 개발의 유연성을 유지하여 다양한 계층의 주민들이 이용함 으로써 운영성과를 높일 수 있는 요인이 된다. 다양한 운영 주체 중 주민조직 직접 운영을 통한 주민들의 역량 강화 및 지역사회 발전과 공동체 의식을 공고히 할 수 있는 발판이 마련될 것이다.

본 연구는 EMG(electromyography) 텍스타일 전극 개발을 목적으로 레이어 수의 디자인 및 원단을 다르게 하여 성능 및 신호 획득 안정성을 평가한다. 레이징 및 프레스 공정을 통하여 텍스타일 전극을 제조하며 Layer-0, Layer-1, Layer-2로 레이어 유무 및 수에 따른 결과를 분석했다. 이에 레이어 유무에 따라서는 근활성 측정에 영향을, 수가 많을수록 높은 성능이 나타남을 확인할 수 있었다. Layer-2 구조로 통일하여 5가지의 원단(네오프렌, 스판덱스 쿠션, 폴리에스테르 100%, 나일론 스판덱스, 광목 캔버스)으로 전극을 제조해 실험해 보았다. 성능적인 면에서, 원단의 중 량이 높은 나일론 스판덱스가 높은 성능을 보였으며, 스판쿠션 텍스타일 전극이 근활성도 수득에 높은 안정성을 보 였다. 이에 위 연구는 레이어에 따른 성능 연관성과 전극-피부사이의 닿는 면적 간의 관계 등을 고찰하여 슬리브 전체의 의복압을 늘리는 대신 특정 센서 측정 부위에만 높은 압력을 가함으로 차후 연구에서 레이어의 수 및 물성에 따른 전극의 공학적 설계 가능성을 제시한 의의가 있다.

Herein, the existing structural design criteria for highway bridge columns with hollow bars were analyzed. Expanding upon previous research focused on the performance analysis of the columns under compressive loads, load– displacement curves were evaluated and crack analysis was performed under cyclic transverse loads. A three-dimensional nonlinear finite-element structural analysis compared the structural performance of existing steel bars, same-reinforced hollow bars, and reduced hollow bars in detail. Results indicated that with regard to elastic or initial crack behavior, the existing steel bars can be replaced by the other bars. Future research should delve into inelastic behavior and strategies to ensure seismic performance.

The purpose of this study was to determine the effect of simulation-based Korea advanced life support training on new nurses' knowledge, clinical performance ability, performer confidence, and learning satisfaction. Methods: This is a non-equivalent controlled pre-post quasi-experimental study. A simulation-based CPR training program was applied to 37 new nurses. Results: The experimental group scored lower on emergency management knowledge (83.65±7.61) than the control group (84.55±9.22), which was not significant (t=-4.46, p=.657). However, the clinical performance ability score was significantly higher in the experimental group (109.59±9.98) than in the control group (100.24±11.87) (t=3.581, p <.001). Performer confidence was significantly higher in the experimental group (23.43±3.29) than in the control group (19.90±3.85) (t=3.69, p〈.001). In addition, the learning satisfaction score of the experimental group (96.16±5.64) was significantly higher than the control group (88.42±11.13) (t=3.72, p< .001). Conclusion: This study confirmed that simulation training is an efficient way to improve new nurses' clinical performance ability, and performer confidence. Therefore, applying simulation training in scenarios can improve new nurses' work competence and contribute to improving the quality of patient care.