• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.47 no.1
• /
• pp.28-37
• /
• 2010

In this paper, the IC (Integrated Circuit) for multi-channel asynchronous communication was designed by using FPGA and VHDL language. The existing chips for asynchronous communication that has been used commercially are composed of one to two channels. Therefore, when communication system with two channels or more is made, the cost becomes high and it becomes complicated for communication system to be realized and also has very little buffer, load that is placed into Microprocessor increases heavily in case of high speed communication or transmission of high-capacity data. The designed IC was improved the function and performance of communication system and reduced costs by designing 8 asynchronous communication channels with only one IC, and it has the size of transmitter/receiver buffer with 256 bytes respectively and consequently high speed communication became possible. To detect errors between communications, it was designed with digital filter and check-sum logic and channel MUX logic so that the malfunction can be prevented and errors can be detected more easily and input/output port regarding each communication channel can be used flexibly and consequently the reliability of system was improved. It was composed and simulated logic of VHDL described by using Cyclone II Series EP2C35F672C8 and QuartusII V8.1 of ALTERA company. In order to show the performance of designed IC, the test was conducted successfully in QuartusII simulation and experiment and the excellency was compared with TL16C550A of TI (Texas Instrument) company and ATmegal28 general-purpose micro controller of ATMEL company that are used widely as chips for asynchronous communication.

• Journal of Preventive Medicine and Public Health
• /
• v.33 no.1
• /
• pp.117-124
• /
• 2000

Objectives : It is the objective of this study to compare hepatotoxicity of nickel chloride and cadmium chloride with each other through IPRL(Isolated Perfused Rat Liver) method. Methods : Biochemical indicator of hepatic function such as AST(aspartate aminotransferase), ALT(alanine aminotransferase), LDH(lactate dehydrogenase) and perfusion flow rate were used as the indicator of hepatotoxicity. Oxygen consumption rate were used as vability indicator. $300({\pm}50)g$ - weighted rats were allocated randomly to each group($0{\mu}M,\;50{\mu}M,\;200{\mu}M\;NiCl_2\;and\;CdCl_2$ exposure) by 5, totally 25. After Krebs-Ringer bicarbonate butler solution flowed into the penal vein and passed the liver cell, it flowed out of vena cava. Liver was administered with each $NiCl_2\;and\;CdCl_2$ of each concentration and observed with buffer solution sampling time. Butler which got out of liver was sampled and then biochemical indicator of hepatotoxicity was measured. Results : AST, ALT, and LDH in buffer increased with sampling time much more in $CdCl_2$ exposure group than $NiCl_2$ exposure group in both 50 and $200{\mu}M$ and statistical significance w3s verified with 2-way repeated ANOVA. Viability was decreased more and more in all substances during passed time. Conclusions : It is inferred that $CdCl_2$ has stronger hepatotoxicity than $NiCl_2$. IPRL method would be used widely for acute hepatotoxicity when considerating the benefit of it.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.3
• /
• pp.155-163
• /
• 2022

The optimization of long-range ensemble climate prediction for rice phenology model with advanced bias correction method is conducted. The daily long-range forecast(6-month) of mean/ minimum/maximum temperature and observation of January to October during 1991-2021 is collected for rice phenology prediction. In this study, the concept of "buffer period" is newly introduced to reduce the problem after bias correction by quantile mapping with constructing the transfer function by month, which evokes the discontinuity at the borders of each month. The four experiments with different lengths of buffer periods(5, 10, 15, 20 days) are implemented, and the best combinations of buffer periods are selected per month and variable. As a result, it is found that root mean square error(RMSE) of temperatures decreases in the range of 4.51 to 15.37%. Furthermore, this improvement of climatic variables quality is linked to the performance of the rice phenology model, thereby reducing RMSE in every rice phenology step at more than 75~100% of Automated Synoptic Observing System stations. Our results indicate the possibility and added values of interdisciplinary study between atmospheric and agriculture sciences.

• Journal of Mushroom
• /
• v.20 no.3
• /
• pp.178-182
• /
• 2022

Despite the long history of mushroom use, studies examining the genetic function of mushrooms and the development of new varieties via bio-molecular methods are significantly lacking compared to those examining other organisms. However, owing to recent developments, attempts have been made to use a novel gene-editing technique involving CRISPR/Cas9 technology and genetic scissors in mushroom studies. In particular, research is actively being conducted to utilize ribonucleoprotein particles (RNPs) that can be genetically edited with high efficiency without foreign gene insertion for ease of selection. However, RNPs are too large for Cas9 protein to pass through the cell membrane of the protoplasmic reticulum. Furthermore, guide RNA is unstable and can be easily decomposed, which remarkably affects gene editing efficiency. In this study, nanoparticles were used to mitigate the shortcomings of RNP-based gene editing techniques and to obtain transformants stably. We used Lentinula edodes (shiitake mushroom) Sanjo705-13 monokaryon strain, which has been successfully used in previous genome editing experiments. To identify a suitable osmotic buffer for the isolation of protoplast, 0.6 M and 1.2 M sucrose, mannitol, sorbitol, and KCl were treated, respectively. In addition, with various nanoparticle-forming materials, experiments were conducted to confirm genome editing efficiency via the formation of nanoparticles with calcium phosphate (CaP), which can be bound to Cas9 protein without any additional amino acid modification. RNPs/NP complex was successfully formed and protected nuclease activity with nucleotide sequence specificity.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.8
• /
• pp.19-27
• /
• 2016

Nowadays the adaptive buffering techniques for burst stream packet configuration and its operation algorithm to save energy in IP core network have been studied. This paper explains the selection method of packet buffering interval for energy saving when configuring burst stream packet at the ingress router in IP core network. Especially the adaptive buffering interval and its implementation scheme are required to improve the energy saving efficiency at the input part of the ingress router. In this paper, we propose the best adaptive buffering scheme that a current buffering interval is adaptively buffering scheme based on the input traffic of the past buffering interval, and analyze its characteristics of energy saving and end-to-end delay by computer simulation. We show the improvement of energy saving effect and reduction of mean delay variation when using an appropriate inverse-function selecting the buffering interval for the configuration of burst stream packet in this paper. We confirm this method have superior properties compared to other method. The proposed method shows that it is less sensitive to the various input traffic type of ingress router and a practical method.

• Journal of Environmental Science International
• /
• v.23 no.7
• /
• pp.1349-1358
• /
• 2014

This study suggests plan of green space management based on the result of research apprehending the characteristic through sorting types of city thermal environment targeting summer which thermal pollution is the most serious. Considering anthropogenic heat, development level of wind road, thermal environment, as a result of types of thermal environment process, it is appeared 36 types, and 10 types is relevant of this research subject. Type I-1, size of building is large, artificial covering area is wide, and thermal load of anthropogenic heat is high, type II-1, development condition of wind road is incomplete as IIlevel, entering cold air is difficult and thermal management and improvement is needed area. Type III-1, scale is large and it is area of origin of cold air, development level of wind road is mostly favorable, type III-2 is revealed as smaller scale than III-1, and small area of origin of cold air. Type IV, anthropogenic heat is $81{\sim}150W/m^2$, average, but development function of wind road is very favorable. Type V, large area of thermal load and the origin of cold air are distributed as similar ratio, and level of development function of wind road is revealed as II level. According to standard of type classification of thermal environment, as a result of suggesting plan of green space management and biotops area ratio, type I-1 is buffer green space and waterway creation, goal biotops area ratio 35%, type II-1 afforestation in site and goal biotops area ratio 40%, type III-1, preservation plan to display the current function continuously is requested. Type IV suggests afforestation of stream current, and type V suggests quantitative increase of green space and goal biotops area ratio 45%.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.7
• /
• pp.1618-1626
• /
• 2013

Virtualization service processes all operation including the data creation, storing, and disposal in a server and transmits processed data as the streaming media form. Therefore, client can use the same environment as the traditional desktop environment without considering the type of device. Virtualization service should consider not only the video quality but also the delay bounds and continuity of video playback for improving the user perceived Quality of Service(QoS) of streaming service. In this paper, we propose a network-adaptive transmission architecture that focuses on guaranteeing QoS requirements for virtualization service. In order to provide those, the proposed architecture have the transmission rate adaptation function based on available bandwidth and the content bit-rate control function based on sender buffer state. Through each function, proposed architecture guarantee the delay bounds and continuity of virtualization contents playback. The simulation results show that proposed network-adaptive transmission architecture provides a improve performance of throughput and transmission delay.

• Journal of Pharmacopuncture
• /
• v.21 no.3
• /
• pp.159-167
• /
• 2018

Objectives: Myocardial reperfusion is the only logical cure for ischemic heart disease. However, ischemic-reperfusion (I/R) injury is one of the underlying factors facilitating and accelerating the apoptosis in the myocardium. This study set to investigate the impact of Teucrium polium (TP) hydro-alcoholic extract on I/R induced apoptosis in the isolated rat heart. Methods: Isolated rat hearts were classified into six groups. The control samples were subjected to 80 min of perfusion with Krebs-Henseleit bicarbonate (KHB) buffer; in control-ischemia group, after primary perfusion (20 min) the hearts were exposed to global ischemia (20 min) and reperfusion (40 min). Pretreated groups were perfused with $500{\mu}M$ of vitamin C and various TP concentrations (0.5, 1, 2 mg/ml) for 20 min, and then the hearts were exposed to ischemia and reperfusion for 20 min and 40 min, respectively. Cardiodynamic parameters including rate pressure product (RPP), heart rate (HR), the maximum up/down rate of left ventricular pressure (${\pm}dp/dt$), left ventricular developed pressure (LVDP), and coronary artery flow (CF) were achieved from Lab Chart software data. The Bax and BCl-2 gene expressions were measured in heart samples. Results: Hearts treated with TP extract and vit C represented a meaningful improvement in cardiac contractile function and CF. The overexpression of Bcl-2, downregulation of Bax, and improvement of apoptotic index (Bax/Bcl-2) were observed in pretreated TP extract and vit C hearts. Conclusion: The TP extract was found to ameliorate the cardiac function in the reperfused myocardium. Also, it can hinder apoptotic pathways causing cardioprotection.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.20 no.4
• /
• pp.77-87
• /
• 2017

In this study, we investigated the physical form of planting foundation of the parks and green spaces in the waterside of Korea and classified them into groups showing common features. It was clssified into 7 kinds of parks and green spaces of 27 waterside parks in Korea including landscape, ecology, art, shields, site boundaries, windbreaks, and soundproofing. As a result, the study was carried out on the detailed type and size estimation through the sampling survey of planting foundation of landscape and ecological type mounding which can be statistically analyzed. Landscape and ecological mounding have the characteristics of securing the ecological stability of the waterside planting areas and the diversity of planting landscape. It is possible to create a green landscape through various terrain changes such as enclosing, focusing, and panoramic view. The physical characteristics of ecological and landscape type mounding can be expressed as height, width, and length And physical data can appear in various forms and sizes depending on the purpose and function of the buffer effect of the land use in the waterside planting areas, the landscape creation, the ecological buffer. In this study, the range of the physical scale for landscape and ecological mounding of waterside parks and green spaces was calculated. The range of the mounding height was analyzed to be less than 1.25m and more than 1.25m and the average height was 0.74~1.08m and 1.75~2.75m respectively. In addition, the range of width of mounding was less than 6.13m, 6.13~17.5m, and more than 17.5m, and the average width of each was 3.45~4.95m, 7.05~10.85m and 31.54~51.54m respectively. The range for the length of mounding was less than 50m, 50~500m, and more than 500m. The mean length of each mounding was 34.0m, 116.3m and 955.8m. It is difficult to distinguish the difference between the waterside planting areas and the urban greenery in the purpose and function of landscape and ecological mounding. However, considering the average distance of 60m from the waterside and the average height of 1.26m, we can conclud that opened planting foundation is prefered to high mounding designs in waterside planting areas. It is expected that the results presented for the improvement of the logical and spatial value of the waterside parks and green areas planting foundation design can be served as the basic data helpful for practical application in landscape architecture planning and design.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.183-184
• /
• 2013

Two main MBE growth techniques have been used: plasma-assisted MBE (PA-MBE), which utilizes a rf plasma to supply active nitrogen, and ammonia MBE, in which nitrogen is supplied by pyrolysis of NH3 on the sample surface during growth. PA-MBE is typically performed under metal-rich growth conditions, which results in the formation of gallium droplets on the sample surface and a narrow range of conditions for optimal growth. In contrast, high-quality GaN films can be grown by ammonia MBE under an excess nitrogen flux, which in principle should result in improved device uniformity due to the elimination of droplets and wider range of stable growth conditions. A drawback of ammonia MBE, on the other hand, is a serious memory effect of NH3 condensed on the cryo-panels and the vicinity of heaters, which ruins the control of critical growth stages, i.e. the native oxide desorption and the surface reconstruction, and the accurate control of V/III ratio, especially in the initial stage of seed layer growth. In this paper, we demonstrate that the reliable and reproducible growth of GaN on Si (110) substrates is successfully achieved by combining two MBE growth technologies using rf plasma and ammonia and setting a proper growth protocol. Samples were grown in a MBE system equipped with both a nitrogen rf plasma source (SVT) and an ammonia source. The ammonia gas purity was ＞99.9999% and further purified by using a getter filter. The custom-made injector designed to focus the ammonia flux onto the substrate was used for the gas delivery, while aluminum and gallium were provided via conventional effusion cells. The growth sequence to minimize the residual ammonia and subsequent memory effects is the following: (1) Native oxides are desorbed at $750^{\circ}C$ (Fig. (a) for [$1^-10$] and [001] azimuth) (2) 40 nm thick AlN is first grown using nitrogen rf plasma source at $900^{\circ}C$ nder the optimized condition to maintain the layer by layer growth of AlN buffer layer and slightly Al-rich condition. (Fig. (b)) (3) After switching to ammonia source, GaN growth is initiated with different V/III ratio and temperature conditions. A streaky RHEED pattern with an appearance of a weak ($2{\times}2$) reconstruction characteristic of Ga-polarity is observed all along the growth of subsequent GaN layer under optimized conditions. (Fig. (c)) The structural properties as well as dislocation densities as a function of growth conditions have been investigated using symmetrical and asymmetrical x-ray rocking curves. The electrical characteristics as a function of buffer and GaN layer growth conditions as well as the growth sequence will be also discussed. Figure: (a) RHEED pattern after oxide desorption (b) after 40 nm thick AlN growth using nitrogen rf plasma source and (c) after 600 nm thick GaN growth using ammonia source for (upper) [110] and (lower) [001] azimuth.