The precast concrete (PC) method allows for simple assembly and disassembly of structures; however, ensuring airtight connections is crucial to prevent energy loss and maintain optimal building performance. This study focuses on the analytical investigation of the shear capacity of precast ultra-high-performance concrete (UHPC) ribs combined with standard concrete PC cladding walls. Five specimens were tested under static loading conditions to evaluate their structural performance and the thermal behavior of the UHPC rib shear keys. Test results indicated that the specimens exhibited remarkable structural performance, with shear capacity approximately three times greater than that of standard concrete. Numerical models were subsequently developed to predict the shear capacity of the shear keys under various loading conditions. A comparison between the experimental results and finite element (FE) models showed a maximum strength difference of less than 10% and a rib displacement error of up to 1.76 mm. These findings demonstrated the efficiency of the FE model for the simulation of the behavior of structures.
In this study, the SBC system, a new mechanical joint method, was developed to improve the constructability of precast concrete (PC) beam-column connections. The reliability of the finite element analysis model was verified through the comparison of experimental results and FEM analysis results. Recently, the intermediate moment frame, a seismic force resistance system, has served as a ramen structure that resists seismic force through beams and columns and has few load-bearing walls, so it is increasingly being applied to PC warehouses and PC factories with high loads and long spans. However, looking at the existing PC beam-column anchorage details, the wire, strand, and lower main bar are overlapped with the anchorage rebar at the end, so they do not satisfy the joint and anchorage requirements for reinforcing bars (KDS 41 17 00 9.3). Therefore, a mechanical joint method (SBC) was developed to meet the relevant standards and improve constructability. Tensile and bending experiments were conducted to examine structural performance, and a finite element analysis model was created. The load-displacement curve and failure pattern confirmed that both the experimental and analysis results were similar, and it was verified that a reliable finite element analysis model was built. In addition, bending tests showed that the larger the thickness of the bolt joint surface of the SBC, the better its structural performance. It was also determined that the system could improve energy dissipation ability and ductility through buckling and yielding occurring in the SBC.
동물의 종 유지에 있어서 교미행동은 매우 중요한 위치를 차지함. 교미과정에서 수컷의 경우 모든 암컷에 대해 성행동을 보이는반면, 암컷은 가장 적절한 교미의 시기를 정하며, 적절한 수컷을 선택하고 교미행동을 보이기 때문에 암컷의 교미행동을 유도하는 과정은 생물학에서 매우 중요한 의미를 지님. 본 연구에서는 초파리 (Drosophila melanogaster) 전자현미경자료와 총신경망분석 (Connectomics)을 이용하여 초파리 뇌에서 암컷의 교미행동을 조절하는 것으로 알려진 pC1신경의 하부신경 pC1b,c가 성적 성숙과정에서 교미를 하고자 하는 욕구 (sexual drive)를 증가시키는 기능을 하는 것을 처음으로 밝힘. 본 연구에서는 처음으로 pC1b,c 신경 내의 cAMP 수준이 교미의 욕구변화를 보여주는 중요한 물질이라는 것을 밝혔고 cAMP의 수준이 오르기 위해서는 신경펩티 드인 Dh44와 그 수용체 GPCR인 Dh44R1과 Dh44R2가 필요하다는 것을 확인함. 또한 cAMP의 변화는 신경내의 CREBB를 통하여 하위 유전자인 pyx (pyrexia)의 발현을 유도한다는 것을 밝힘. 본 연구로 종 유지 메커니즘을 좀 더 이해할 수 있음.
The global PC game market is enjoying sustainable growth, and diverse grow types and quantities of games. Among the many, the theme of horror circulates in the market. Ahead of placing orders, the poster initiates the first exchange with the game, players and consumers, and affects buyers' behavior and cognition subject to its color. What is an eye-catching poster? Different games have different styles and philosophies, so it leads to a certain degree of variation in the poster design of each game. In order to study the common points of popular game color design. For the top 10 most acclaimed horror games on STEAM (PC), 5 to 6 color elements were mined from each poster for analysis and offered suggestions on poster design. First, in the color selection, more warm colors are on the list of recommendation, such as yellow, you can also choose cool colors such as blue. Second, high-saturation and high-brightness colors speak for better choice. The design of color is not absolute, and this thesis only analyzes the posters of commercially circulated and well-received horror games. It is hoped to provide insights for user-friendly interface design, support and understanding of user behaviors.
The paper introduces an experimental program for the newly developed vertical joints between Precast Concrete (PC) walls to improve their in-plane shear capacity. Compared to the existing vertical joints, two types of vertical joints were developed by increasing the transverse reinforcement ratio and improving frictional force at the joint interface. A total of four specimens including the Reinforced Concrete (RC) wall and PC walls with developed vertical joints were designed and constructed. The constructed specimens were experimentally investigated through monotonic shear tests. The observed damage, load-deformation relationship, strain and strength are investigated and compared with the cases of RC wall specimen. Experimental results indicate that the maximum force and initial stiffness of the PC wall with proposed vertical joints were decreased by comparing with those of RC wall. However, the ultimate displacement increased by up to 217.30% compared to the RC wall specimen. In addition, brittle failure did not occurred and relatively few cracks and damages occurred.
공상과학소설(Science-Fiction; 이후 Sci-Fi로 표기)은 미래 세계에 대한 인간의 판타지를 표현하는 장르다. 이는 TV 쇼, 영화, 게임 분야에서 항상 뜨거운 주제였다. Sci-Fi 영화와 Sci-Fi 게임은 대부분 상위권에 오르고 있다. 하지만, 학계에서는 주로 Sci-Fi 영화에서 대한 논의에 더 집중하는 경향이 있다. 예를 들어, <Research on Color Modes of Well-known Contemporary Films(2020)>에 따르면, 최근 몇 년 동안 할리우드 Sci-Fi 영화의 주류 색상은 빨간색과 파란색에서 주황색, 노란색, 파란색, 녹색으로 바뀌었다고 분석하고 있다. 또한, Sci-Fi 영화와 관련된 질적 연구와 연구의 많은 성과가 있었다. 그러나 Sci-Fi 게임의 색조 경향에 대한 연구와 연구 는 매우 부족한 상황이다. 이에 본 논문은 Adams Roberts의 Sci-Fi 소설의 7가지 요소를 사용 한다. 이러한 7 가지 요소에 대한 Metacritic 점수가 사례 선택의 표준으로 사용되었다. 본 연구의 분석 대상으로는<HALO 3>, <Death Stranding>, <Cyberpunk 2077> 등 우수 PC게임 3종이 선정하였다. 또한, 데이터 분석은 NCS 색상 시스템을 기반으로 수행되어 Sci-Fi 게임의 색조 유사성에 대해 논의한다. 마지막으로, 우수한 게임의 색상 적 용에 대한 주요 성향을 결론짓고 요약함으로써, 본 연구는 Sci-Fi 게임의 색상 생산에 대한 몇 가지 이론적 참 조와 기초 데이터를 제공하고자 한다.
Recently, interest in OSC(Off Site Construction) is increasing due to the trend of a decrease in skilled workers and an increase in labor costs. In this regard, PC(Precast Concrete) is being reviewed for apartments, the most common type of housing in Korea. As the biggest concern for PC apartment houses, civil complaints such as inter-floor noise and leakage were presented. In this study, the details of the joints were reviewed based on the past cases of PC apartments, and the details of the recently constructed or planned PC apartments were investigated. Through this, the leakage path in the past was analyzed through the existing research literature and data. And wall type RC and PC apartment joint leakage test was performed and we found the needs for a detail of waterproof steps, sealant. Also, joint details were investigated for a rahmen type apartment housing under construction. At last, A discussion was conducted on the direction for a detailed proposal of an improved joint in the future.
The event recording devices such as EDR and DTG have recently been developed and installed in automobiles. The reliability of EDR application is being conducted in many previous studies, but with the development and development of autonomous vehicles, it is necessary to study the reliability of EDR and DTG application results for programs that can analyze autonomous driving. Therefore, in this study, the analysis was carried out in a way to secure the reliability of the application results of EDR and DTG of Carmaker, which can analyze the traffic accident analysis program PC-Crash and autonomous driving, and secure the reliability of the Carmaker program that applied EDR in Korea and abroad. As a result of the analysis, it was found that the speed error rate gradually increased from high speed to low speed, and the maximum error speed was less than 5 km/h through the average error rate for each speed. In the future, it is thought that it can be usefully used for analysis of traffic accidents in the event of autonomous vehicle accidents.
This study was conducted for the purpose of suggesting a standard that can be used under ambient temperature by improving the low mechanical and thermal properties of ABS. PC was used as a filler, and post-curing conditions of the ABS/PC blend injection material were investigated. It was found that the ABS/PC blend injection material having a PC content of 20 wt.% or more showed little change in tensile properties at a temperature of 50°C, and a decrease in tensile properties of less than 10% at 80°C.
A Y6-xCa1.5xSi11N20O:Ce3+(x=2.5) oxynitride phosphor is synthesized at 1,750 oC in a mixed gas atmosphere of 5% H2 and 95 % N2 by using YN, Ca3N2, Si3N4, and CeO2 as raw material reagents. The crystal structure is a trigonal crystal system that has a P31c (no.159) space group and has lattice parameters of a, b = 9.8876(3), and c = 10.6806(4). This structure is an Er6Si11N20O structure type in which a Y6-xCa1.5xSi11N20O structure is formed by substituting a trivalent Y3+ element and a bivalent Ca2+ element at the position of Er element having an oxidation number of +3. Here, the charge difference caused by different oxidation numbers is balanced by the occupancy of a partially vacant 2c site and an O/N anion ratio in the Er6Si11N20O structure type. The Y6-xCa1.5xSi11N20O:Ce3+ (x = 2.5) phosphor is yellow powder with yellow luminescence; performing Rietveld refinement on the phosphor on the basis of the data obtained by XRD measurement results in the lattice parameters as described above. The Y6-xCa1.5xSi11N20O:Ce3+ (x = 2.5) phosphor has a broad emission band due to Ce3+ as an activator with the center wavelength of 565 nm. This phosphor has a broader emission band than a YAG:Ce3+ phosphor, which is a representative LED phosphor, and thus extends further into the blue and red spectrum ranges. Accordingly, this phosphor is an interesting phosphor that can be used for 1pc-LED with an improved color rendering index.
Green tea polyphenol (–)-epigallocatechin-3-gallate (EGCG) is a potent antioxidant with protective effects against neurotoxicity. However, it is currently unclear whether EGCG protects neuronal cells against radiation-induced damage. Therefore, the objective of this study was to investigate the effects of EGCG on ultraviolet (UV)-induced oxidative stress and apoptosis in PC12 cells. The effects of UV irradiation included apoptotic cell death, which was associated with DNA fragmentation, reactive oxygen species (ROS) production, enhanced caspase-3 and caspase-9 activity, and poly (ADP-ribose) polymerase cleavage. UV irradiation also increased the Bax/Bcl-2 ratio and mitochondrial pathway-associated cytochrome c expression. However, pretreatment with EGCG before UV exposure markedly decreased UV-induced DNA fragmentation and ROS production. Furthermore, the UV irradiationinduced increase in Bax/Bcl-2 ratio, cytochrome c upregulation, and caspase-3 and caspase-9 activation were each ameliorated by EGCG pretreatment. Additionally, EGCG suppressed UV-induced phosphorylation of p38 and rescued UV-downregulated phosphorylation of ERK. Taken together, these results suggest that EGCG prevents UV irradiationinduced apoptosis in PC12 cells by scavenging ROS and inhibiting the mitochondrial pathways known to play a crucial role in apoptosis. In addition, EGCG inhibits UV-induced apoptosis via JNK inactivation and ERK activation in PC12 cells. Thus, EGCG represents a potential neuroprotective agent that could be applied to prevent neuronal cell death induced by UV irradiation.
A combination of Polycarbonate (PC) material and Polymethylmethacrylate (PMMA), fabricated using an injection molding machine, has been investigated to determine its advantages, as studied in Ref. 1). This paper aims to investigate the optimization of PMMA/PC blend for both tensile yield strength and impact strength. Furthermore, interaction effects of process conditions on mechanical properties including tensile yield strength and impact strength of PMMA/PC blend by injection molding process are interpreted in this study. Tensile and impact specimens are designed following ASTM, type V, and are fabricated by injection molding process. The processing conditions such as melt temperature, mold temperature, packing pressure, and cooling time are applied; each factor has three levels. As a result, in comparison with optimization of separated responses, mechanical properties of PMMA/PC are found to decrease when optimizing both tensile and impact strengths simultaneously. The melt temperature is found to be the most significant interaction parameter with the mold temperature and packing pressure. In addition, there is more interaction between the mold temperature and cooling time. This investigation provides a useful understanding of the control of injection molding processing of polymer blends in optical application.
The energy demands of the world have been accelerating drastically because of the technological development, population growth and changing in living conditions for a couple of decades. A number of different techniques, such as batteries and capacitors, were developed in the past to meet the demands, but the gap, especially in energy storage, has been increasing substantially. Among the other energy storage devices, supercapacitors have been advancing rapidly to fill the gap between conventional capacitors and rechargeable batteries. In this study, natural resources such as pistachio and acorn shells were used to produce the activated carbons for electrode applications in a supercapacitor (or an electrical double-layer capacitor— EDLC). The activated carbon was synthesized at two different temperatures of 700 °C and 900 °C to study its effect on porosity and performance in the supercapacitor. The morphology of the activated carbon was studied using scanning electron microscopy (SEM). A solution of tetraethylammonium tetrafluoroborate ( TEABF4)/propylene carbonate (PC) was prepared to utilize in supercapacitor manufacturing. The performance of the EDLC was investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy. Activated carbons from both the pistachio and acorn shells synthesized at 700 °C in argon gas for two hours exhibited better surface textures and porosity. There activated carbons also exhibited more capacitor-like behavior and lower real impedances, indicating that they would have superior performance compared to the activated carbons obtained at 900 °C. This study may be used to integrate some of natural resources into high-tech energy storage applications for sustainable developments.
Cognitive impairment is considered to be key research topics in the field of neurodegenerative diseases and in understanding of learning and memory. In the present study, we investigated neuroprotective effects of Schisandra chinensis (SC) and Ribes fasciculatum (RF) extracts in hydrogen peroxide-induced neuronal cell death in vitro and scopolamine-induced cognitive impairment in Sprague Dawley® (SD) rat in vivo. Apoptotic cell death in neuroblastic PC12 cell line was induced by hydrogen peroxide for 1 hour at 100 μM. However, mixture of SC and RF treatment prevented peroxide induced PC12 cell death with no neurotoxic effects. For in vivo experiment, the effect of SC and RF extracts on scopolamine-induced cognitive impairment in SD rat was evaluated by spontaneous alternation behavior in Y-Maze test. After 30 min scopolamine injection, the scopolamine-induced rats presented significantly decreased % spontaneous alteration and acetylcholine level, compared to non-induced group. However, treatment of SC+RF extracts rescued the reduced % spontaneous alteration with acetylcholine concentration from hippocampus in scopolamineinduced rats. These results suggested that mixture of SC and RF extract may be a potential natural therapeutic agent for the prevention of cognitive impairment.
The purpose of this study was to investigate the protective effect on oxidative stress induced PC12 cells, and volatile flavor composition of essential oils derived from medicinal plant seeds- Gossypium hirsutum L. (G. hirsutum), Coix lachryma-jobi (C. lachryma-jobi) and Oenothera biennis (O. biennis). The essential oils were obtained by the solvent (hexane) extraction method from the seeds. The essential oils of the seeds were analyzed by the solid-phase micro-extraction gas chromatography mass spectrometry (SPME-GC/MS). The major compounds of G. hirsutum, C. lachryma-jobi and O. biennis were cyclonexanol (16.65%), β-asarone (14.29%) and ylangene (50.01%). The DPPH radical scavenging activity (IC50) was the highest value of 8.52 mg/mL in the O. biennis. Additionally, IC50 values of G. hirsutum and C. lachryma-jobi were 26.76 mg/mL and 36.81 mg/mL. For the oxidative stress on PC12 cells, we treated with hydrogen peroxide (H2O2). The pretreatment of oxidative stress induced PC12 cells with all the essential oils preserved or increased their cell viability and G. hirsutum and O. biennis attenuated the ROS generation (by 68.75% and 56.25% vs. H2O2 control). The results of this study suggest that the essential oils derived from medicinal plant seeds could be used as valuable back data as a natural essential oil material to prevent neurodegenerative diseases by protecting neuro-cells.