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Liver fibrosis is an excessive wound healing process that occurs in response to liver damage depending on underlying aetiologies. Currently, there are no effective therapies and FDA-approved therapeutics for the treatment of liver fibrosis except liver transplantation. Multipotent adipose-derived stem cells (ADSCs) have received significant attention as regenerative medicine for liver fibrosis owing to their advantages over stem cells with other origins. However, intrinsic limitations of stem cell therapies, such as cellular rejection and tumor formation, have impeded clinical applications of the ADSC-based liver therapeutics. To overcome these problems, the extracellular nanovesicles (ENVs) responsible for the therapeutic effect of ADSCs (A-ENVs) have shown considerable promise as cell-free therapeutics for liver diseases. However, A-ENVs have not been used for the treatment of intractable chronic liver diseases including liver fibrosis and cirrhosis. Therefore, in this study, we investigated the in vitro and in vivo antifibrotic efficacy of A-ENVs in thioacetamide-induced liver fibrosis models. A-ENVs significantly downregulated the expression of fibrogenic markers, such as matrix metalloproteinase-2, collagen-1, and alpha-smooth muscle actin. The systemic administration of A-ENVs led to high accumulation in fibrotic liver tissue and the restoration of liver functionality in liver fibrosis models through a marked reduction in α-SMA and collagen deposition. These results demonstrate the significant potential of A-ENVs for use as extracellular nanovesicles-based therapeutics in the treatment of liver fibrosis and possibly other intractable chronic liver diseases.

A semi-submersible structure has been widely used for offshore drilling and production of oil and gas. The small water plane area makes the structure very sensitive to weight increase in terms of payload and stability. Therefore, it is necessary to lighten the substructure from the early design stage. This study aims at an optimization of hull structure based on a sophisticated yield and buckling strength in accordance with classification rules. An in-house strength assessment system is developed to automate the procedure such as a generation of buckling panels, a collection of required panel information, automatic buckling and yield check and so on. The developed system enables an automatic yield and buckling strength check of all panels composing the hull structure at each iteration of the optimization. Design variables are plate thickness and stiffener section profiles. In order to overcome the difficulty of large number of design variables and the computational burden of FE analysis, various methods are proposed. The steepest descent method is selected as the optimization algorithm for an efficient search. For a reduction of the number of design variables and a direct application to practical design, the stiffener section variable is determined by selecting one from a pre-defined standard library. Plate thickness is also discretized at 0.5t interval. The number of FE analysis is reduced by using equations to analytically estimating the stress changes in gradient calculation and line search steps. As an endeavor to robust optimization, the number of design variables to be simultaneously optimized is divided by grouping the scantling variables by the plane. A sequential optimization is performed group by group. As a verification example, a central column of a semi-submersible structure is optimized and compared with a conventional optimization of all design variables at once. Keywords: Semi-submersible structure, Steepest descent method, Weight optimization, Buckling strength, Yield strength

A trust management mechanism for mobile ad hoc networks (MANETs) is proposed to cope with security issues that MANETs face due to time constraints as well as resource constraints in bandwidth, computational power, battery life, and unique wireless characteristics. The trust-based reputation scheme GlobalTrust is a reliable trust management mechanism. In this paper, a clustering algorithm is applied to the GlobalTrust scheme (named Cluster-based GlobalTrust (CGTrust)) to find the optimal group size to minimize the configuration time, which consists of trust information computational time and complexity, while having to satisfy the trust reliability requirements. The optimal number of clusters is derived from the minimizing point of the computation complexity function. Simulation results show that the computational time and complexity of CGTrust are controllable and can be used effectively in time critical network operations that require trust analysis.

The flowfield characteristics of a square prism having a small triangular prism at the upstream side were investigated by visualizing the flow field using PIV. The ratio of the width of the triangular prism to that of the square prism and the gap ratios between the square and triangular prisms were selected as the experimental parameters. The results are summarized as follows. The Strouhal number measured on the wake side of the square prism, which had the same characteristics as the drag reduction rate, in- creased, and then decreased with the gap ratio for the same width ratio. For a square prism having a small triangular prism, the stagnation regions were represented at the upstream and downstream sides of the square prism. The size of the stagnation region in- creased with the width ratio at the upstream side of the square prism, and decreased at the downstream side.

The purpose of this study is to investigate the effect of the impinging plate on combustion process in Diesel engine. Especially, the variation of exhaust emission and engine performance by the change of fuel injection timing and fuel injection pressure between the trial engine with impinging plate and the prototype engine were examined. The nitrogen oxide concentration of the trial engine decreased more than 50% compared to the prototype engine, however, smoke concentration of the trial engine indicated higher degree than the prototype engine. The smoke concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection timing become faster, whereas the nitrogen oxide concentration decreased as the fuel injection timing is retarded. The nitrogen oxide concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection pressure become lower. But smoke concentration decreased as the fuel injection pressure become higher.

This study evaluated experimentally static strength for bogie frame of an urban maglev train including performing fatigue analysis, cumulative damage and fatigue test based on a developed fatigue load and as a final outcome, aimed to propose a fatigue strength evaluation method for the bogie frame of urban maglev. The results of FEM analysis adopting load combinations showed that all data was under a fatigue limit of the butt welded joint made of A6005 in Goodman diagram. The cumulative fatigue damage was calculated at the highest level from a bolt connecting area of electromagnetic pole in casting block but the total sum was evaluated as D = 0.808 based on 1 × 107 cycles, which indicates it did not exceed the failure criteria. In addition, as the results of fatigue test, there was no crack on the any position of the bogie frame with the outcomes that corresponded to the results of fatigue test.

The protection switching technology is widely adopted in the fiber-optical transmission equipments based on TDM(Time Division Multiplexing), such as PDH, SDH/SONET. A variety of protection switching algorithms for Ethernet networks and the progress of standardization are summarized in the document. There are several kinds of protection switching algorithms for Ethernet networks, such as STP, RSTP, MSTP and etc. However, since Ethernet signal move through detour route, it causes much time to recover. Accordingly, it is difficult to secure a usability of Ethernet networks and QOS(Quality of Service). Also, if the protection switching protocol standardized by IEEE and ITU-T is used, it remains a inherent network switching time for protection. Therefore, a specific protection switching algorithm for Ethernet are needed for seamless and stable operation of Ethernet networks service for Distribution Automation System(DAS). A reliable protection algorithm with no switching delay time is very important to implement Self-healing service for DAS. This study of FPGA based protection switching algorithm for Ethernet networks shows that in case of faults occurrence on distribution power network, immediate fault isolation and restoration are conducted through interaction with distribution equipments using P2P(Peer to Peer) communication for protection coordination. It is concluded that FPGA based protection switching algorithm for Ethernet networks available 0ms switching time is crucial technology to secure reliability of DAS.

초록원자력발전소 증기발생기 세관은 방사성물질이 외부로 누출되지 않도록 압력경계 역할을 하는 주요부품이다. 설비 운전기간이 증가함에 따라 이차측에서 유입된 슬러지가 증기발생기 2차측 유체 흐름을 따라 상부로 이동하면서 유체비등과 난류에 의해 세관 외면에 스케일이 부착되어 세관열화, 유로홈 막힘 및 열전달을 감소시키는 파울링을 유발하는 원인으로 작용한다. 따라서, 원전 운영자는 세관 외면에 쌓인 스케일의 두께를 확인하여 일정시점이 되면 화학세정 등의 정비를 수행한다. 본 논문에서는 보빈코일 와전류신호를 이용하여 세관 외면에 부착된 스케일 두께를 정량적으로 평가하는 기술을 개발하고자 스케일 시험편을 제작하여 스케일 두께와 와전류신호 진폭 간의 상관관계를 분석하였고, 이를 바탕으로 스케일의 두께를 정량적으로 평가하는 기법과 대량의 와전류 데이터를 평가할 수 있는 프로그램을 개발하였다. 주요용어:스케일, 슬러지, 와전류신호, 증기발생기, 보빈코일Abstract Steam generator is one of the major components of nuclear power plant and steam generator tubes are the pressure boundary between primary and secondary side, which makes them critical for nuclear safety. As the operating time of nuclear power plant increases, not only damage mechanisms but also scaled deposits on steam generator tubes are known to be problematic causing tube support flow hole blockage and heat fouling. The ability to assess the extent and location of scaled deposits on tubes became essential for management and maintenance of steam generator and eddy current bobbin data can be utilized to measure thickness of scale on tubes. In this paper, tube reference standards with various thickness of scaled deposit has been set up to provide information about the overall deposit condition of steam generator tubes, providing essential tool for steam generator management and maintenance to predict and prevent future damages. Also, methodology to automatically measure scale thickness on tubes has been developed and applied to field data to estimate overall scale amount.Keywords: Scale, Sludge, Deposit Mapping, Eddy Current, Steam Generator, Bobbin Coil

Stem cell therapy requires large numbers of stem cells to replace damaged tissues, but only limited numbers of stem cells can be harvested from a single patient. To obtain large quantities of stem cells with differentiation potential, we explored a spinner culture system using human extracellular matrix (hECM) powders. The hECM was extracted from adipose tissue and fabricated into powders. Human adipose-derived stem cells (hASCs) were isolated, seeded on hECM powders, and cultivated in a spinner flask. The 3-D culture system, using hECM powders, was highly effective for promoting cell proliferation. The number of hASCs in the 3-D culture system significantly increased for 10 days, resulting in an approximately 10-fold expansion, whereas a traditional 2-D culture system showed just a 2.8-fold expansion. Surface markers, transcriptional factors, and differentiation potential of hASCs were assayed to identify the characteristics of proliferated cells in 3-D culture system. The hASCs expressed the pluripotency markers, Oct-4 and Sox-2 during 3-D culture and retained their capacity to differentiate into adipogenic, osteogenic, and chondrogenic lineages. These findings demonstrate that the 3-D culture systems using hECM powders provide an efficient in vitro environment for stem cell proliferation, and could act as stem cell delivery carriers for autologous tissue engineering and cell therapy.

Because there has been a recent increase in the use of low calorific coal compared to standard coal, it is crucial to control the char flame length governing the burning life-time of coal in a coal-fired utility boiler. The main objective of this study is to develop a simplified model that can theoretically predict the flame length for burning coal in a laboratory-scale entrained laminar flow reactor (LFR) system. The char burning behavior was experimentally observed when sub-bituminous pulverized coal was fed into the LFR under burning conditions similar to those in a real boiler: a heating rate of 1000 K/s, an oxygen molar fraction of 7.7 %, and reacting flue gas temperatures ranging from 1500 to 2000 K. By using the theoretical model developed in this study, the effect of particle size on the coal flame length was exclusively addressed. In this model, the effect of particle mass was eliminated to compare with the experimental result performed under a constant mass feeding of coal. Overall, the computed results for the coal flame length were in good agreement with the experimental data, particularly when the external oxygen diffusion effect was considered in the model.

In this study, the effect of particle size on the combustion characteristics of pulverized sub-bituminous coal was experimentally investigated. A laminar-flow-entrained reactor was designed and implemented to realize the desired heating ratio and temperature corresponding to the combustion atmosphere of a pulverized-coal-fueled furnace. The flame length and structure of burning particles according to different sizes were investigated. Coal combustion processes were clearly distinguished by direct visual observation of the flame structure. The onset point of volatile ignition is greatly affected by changes in the particle size, and the burning time of the volatiles is least affected by changes in the particle size. The length and instability of char flame also increase with the increase of the particle size. However, the char consumption rate within the residential time remains nearly constant.

Cost effective microelectromechanical system (MEMS) packaging methods have been required, because the cost portion of the MEMS package is more than 80% of the manufacturing cost of a MEMS device. For this reason, cost-effective MEMS packaging is proposed in this paper for mass production using copper (Cu) lead frames (L/F) as a preplated frame (PPF). Package types include an epoxy molding compound (EMC) cavity wall and an on-frame type. The EMC-cavity package consists of a substrate, a cavity wall and a flat lid on top of the cavity. The on-frame package has a folded lid without a cavity wall. Finite element method (FEM) numerical modeling is performed to anticipate the mechanical warpage and stress of the packages. Assembled MEMS cavity packages were tested for wire pulling, lid pulling, hermetic test, and reliability tests in order to prove the feasibility of this packaging. The wire bonding strength was improved by 40% using plasma cleaning before wire bonding. Through a lid pulling test, a lid bonding strength of 2.40 kgf on average was obtained using an epoxy adhesive. Finally, all samples of the packages passed the reliability tests of the TC, HAST, and HTST, standardized by Joint Electron Device Engineering Council (JEDEC). Also, this cavity package showed excellent hermeticity through leak tests.

We propose resonance mode in a racetrack cavity with hexagonal corners, in which the modes are guided by both boundaries of the corner. The modes were demonstrated by investigating the laser oscillations in semiconductor cavities.

Up to now, SiP integration is widely used to increase chip integration density as well as flexibility of combination in heterogeneous devices. Emerging integration and stacking technologies such as 3D integration, TSV (Through Silicon Via), die-to-die proximity communications, EAD (Embedded Active Devices) are becoming greater attention. If we call the first generation SiP integration as “SiP1.0”, what is “SiP2.0” ? When and how is it practical? Each panelists will give their anticipation of future SiP, or “SiP2.0”. This panel talk is not an “A vs. B” type of debate, but more like an evening talk where each panelist presents their visions on the next generation SiP.

The committee technique for neural networks has been widely used for pattern recognitions in speech and vision studies. In this study, the committee technique is applied to damage estimation of structures for the purpose of structural health monitoring. The input to the neural networks consists of the modal parameters, and the output is composed of the element-level damage indices. Multiple neural networks are constructed and each individual neural networks is trained independently with different initial synaptic weights. Then, the estimated damage indices from different neural networks are averaged. Several committee methods were investigated and used to estimate the element-level damage locations and severities. The validity of the committee technique for damage estimation was examined on a frame structure through numerical simulation. Then experiments were carried out on a bridge model with a composite cross section subjected to vehicle loadings. It has been found that the estimated damage indices improve significantly by employing the committee technique.

A new edge block coding mode of digital video coding is presented. For the detailed reconstructionof edge blocks, an adaptive block truncation coding is proposed using the properties of block truncation coding and intensity sensitivity of human Visual System. To use this algorithm in video sequence coding, an edge block detection mechanism is devised and pixel reallocation, scan mode selection, onedimensional DPCM, and two dimensional run length coding are explained. Measured with objective andsubjective criteria, the new algorithm is shown to have better performance than other algorithms. Keywords : Moving Picture Experts Group, block truncation coding, edge block coding, Human Visual System 1 Introduction ISO-IEC's MPEG2{1] describes the coding mechanism of digital video in which the bit rate is above 1.5Mbps. MPEG2 has a higher bit rate than that of MPEG1, and active research is being done in the fields of storage media for compressed digital video, and its transmission over the asynchronous transfermode(ATM) networks, and so on.At the rate of 15Mbps which is the upper bound of Main Profile at Main Level decoder, MPEG2 hasalmost the same quality as the original image. But the performance of MPEG2 at a lower bit rate showsmany artifacts when used with graphics images, animated images, and scrolling text images. Such imageshave many edge blocks in common, and the DCT generates a mosquito effect and false contours as well asblurrings around edges.As solutions of such problems with the DCT, several methods are proposed using other coding modesrather than the DCT to preserve edge information of the input signal. One method uses Block TruncationCoding(BTC)[2] and the other uses Non Transform Coding (NTC)technique[3]. In the former, informationfor BTC is transmitted, and the difference signal between input and BTC is transmitted using DCT also.This causes redundancy of information transmission. The latter is an heuristic algorithm and shows a"sticking effect" between the objects located closely each other. Furthermore its quantizer which wasoriginally intended to be used for the DCT coefficients causes an out-of-range problem in reconstructedpixels and results in disappearance of parts of an object.In this paper, we propose an edge block coding mode, Adaptive Block Truncation Coding(ABTC) indigital video coding. ABTC reconstruct each block with one, two, three, or four levels according to itslocal activity and the property of the Human Visual System(HVS)'s intensity sensitivity.

SINCE Glinski 1 and Simmonds 2 in 1913 and 1914 described pituitary abscesses accompanying systemic bacterial infection there have been only two such reports in the world literature. 3,4 We now report the case of a patient with diabetes mellitus and fatal Escherichia coli septicemia in whom severe hypoglycemic reactions developed. An abscess of the pituitary gland was found on postmortem examination. Report of a Case A 47-year-old woman with a ten-year history of diabetes mellitus was admitted to the hospital because of agitation and disorientation. Her temperature was 38 C, pulse rate 120 beats per minute, and blood pressure 70/50 mm Hg. She had been taking 40 units of isophane insulin suspension daily, with good control of diabetes and without any history of hypoglycemia or ketoacidosis. On admission, blood glucose level was 400 mg/100 ml with glycosuria (3+ ) and albuminuria (3+ ), as well as many white blood cells (WBC)