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NiCo alloys are electroplated in sulfate bath. The concentration of cobalt sulfate and current density were varied to optimize the surface hardness. The properties of NiCo deposits were analyzed using field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The surface hardness of the NiCo alloy was increased up to 500 Hv at 24 wt% Co in the deposits due to the grain refinement. The size of grain was reduced to 12 nm. The residual stress of the deposits was varied from tensile to compressive as the saccharin concentration increased. The zero residual stress was achieved at 0.05 g/L saccharin addition.

Acquiring initial synchronization with auto-correlation is simple and reliable method in wireless OFDM systems. However, recent trend of making use of wide-band frequency resources and accompanying high-frequency feature makes their implementation problematic. In order to solve this difficulty in developing our wireless backhaul system, we partitioned input signal into a few slower operation paths. This paper suggests how to acquire initial synchronization in this environment with minimum hardware and achieving performance goal in desired channel environment.

Electroless nickel immersion gold (ENIG) has been widely used for surface finishing in PCB industry, however surface defects are sometimes found during PCB soldering process. These defects cause failures in soldering on PCB and consequently cause poor safety probability of products. The formation mechanism of the defects in the NiP layer was investigated. Three parameters on the black pads were analyzed. First, morphology was analyzed with changing metal turn over (MTO) numbers. Second, pH of Ni solution was changed in the ENIG process. Third, stress of NiP layers was analyzed at different pH. The relationship between each defect and P contents was analyzed. High open circuit voltage (OCV) can cause the poor surface morphologies as well as the defects. High and large difference of P contents in NiP layer can act the important role in the formation of black pads. The high tensile stress can also be another factor of the formation of black pads.

A kinetic model for the catalytic wet air oxidation of aqueous ammonia over Ru/TiO2 catalyst was developed considering the consecutive reaction steps as follows: (i) formation of active oxygen sites O* by the dissociative adsorption of aqueous O2 on the catalyst, (ii) oxidation of aqueous NH3 by the reaction with three O* sites to produce HNO2, (iii) aqueous phase dissociation of HNO2 into H+ and NO2−, (iv) formation of NH4+ by the association of NH3 with the HNO2-dissociated H+, (v) formation of N2 by the aqueous phase reaction between NO2− and NH4+, (vi) formation of NO3 by the reaction of NO2− with an O* site. For each reaction step, a rate equation was derived and its kinetic parameters were optimized by experimental data fitting. Activation energies for the reactions (ii), (v), and (vi) were 123.1, 76.7, and 54.5 kJ/mol, respectively, suggesting that the oxidation reaction of aqueous NH3 to HNO2 was a ratedetermining step. From the simulation using the kinetic parameters determined, the initial pH adjustment of the ammonia solution proved to be critical for determining the oxidation product selectivity between desirable N2 and undesirable NO3− as well as the degree of oxidation conversion of ammonia.

The tires, suspension type, and steering system can all cause pulling during braking. Among these, a drag link steering system and leaf-type suspension system are significant causes of vehicle pulling. In this study, the pulling problem is analyzed using the vehicle analysis program "ADAMS/CAR." The drag link and leaf spring behavior is analyzed to find the key reason for pulling. After this, the optimization program "Visual DOC" is used with "ADAMS/CAR" to find a steering link connection point to reduce pulling. After conducting this simulation, K&C (kinematic & compliance) test simulation with a modified connection point is conducted to determine whether the vehicle performance improves. Through a full braking simulation, it is verified that the pulling distance is reduced at braking.

Objective Sepsis is the most common cause of acute kidney injury in critically ill patients; however, the mechanisms leading to acute kidney injury in sepsis remain elusive. Although sepsis has been considered an excessive systemic inflammatory response, clinical trials that inhibit inflammation have been shown to have no effect. The purpose of this study was to examine the pathophysiology of septic acute kidney injury focusing on immune responses and renal tubular cell apoptosis by providing an on-site quantitative comparison between septic- and ischemia/reperfusion-induced acute kidney injury. Design Twenty-four hours after cecal ligation and puncture or ischemia/reperfusion injury, biochemical, histologic, and cytokine changes were compared in C57BL/6 mice. Apoptosis was assessed, and the effect of caspase 3 inhibition on renal function was also examined. The percentage of regulatory T cells and the effect of depletion were determined and compared with ischemia/reperfusion-induced acute kidney injury. The effect of interleukin-10 blocking was also compared. Measurements and main results Despite comparable renal dysfunction, acute tubular necrosis or inflammation was minimal in septic kidneys. However, tubular cell apoptosis was prominent, and caspase 3 activity was positively correlated with renal dysfunction. A decrease in apoptosis by caspase 3 inhibitor resulted in attenuation of renal dysfunction. In assessment of systemic immunity, septic acute kidney injury was associated with an increase in interleukin-10, and also showed massive immune cell apoptosis with increased regulatory T cells. In contrast to ischemia/reperfusion injury in which depletion of regulatory T cells aggravated renal injury, depletion of regulatory T cells before cecal ligation and puncture resulted in renoprotection. In addition, blocking interleukin-10 rescued septic mice from the development of acute kidney injury, whereas it had no effect in ischemia/reperfusion injury. Conclusions Pathogenesis of septic acute kidney injury is thought to be different from that of ischemia/reperfusion-induced acute kidney injury. Our data showed a link between apoptosis, immune suppression, and the development of acute kidney injury during sepsis and suggest that strategies targeting apoptosis or enhancing immunity might be a potential therapeutic strategy for septic acute kidney injury.

Objectives This purpose of this paper is to introduce the status of the Asan Medical Center (AMC) medical information system with respect to healthcare quality improvement. Methods Asan Medical Information System (AMIS) is projected to become a completely electronic and digital information hospital. AMIS has played a role in improving the health care quality based on the following measures: safety, effectiveness, patient-centeredness, timeliness, efficiency, privacy, and security. Results AMIS consisted of several distinctive systems: order communication system, electronic medical record, picture archiving communication system, clinical research information system, data warehouse, enterprise resource planning, IT service management system, and disaster recovery system. The most distinctive features of AMIS were the high alert-medication recognition & management system, the integrated and severity stratified alert system, the integrated patient monitoring system, the perioperative diabetic care monitoring and support system, and the clinical indicator management system. Conclusions AMIS provides IT services for AMC, 7 affiliated hospitals and over 5,000 partners clinics, and was developed to improve healthcare services. The current challenge of AMIS is standard and interoperability. A global health IT strategy is needed to get through the current challenges and to provide new services as needed.

The synthesis and characterization of the Ba 2 TiSi 2 O 8 films are described. The Ba 2 TiSi 2 O 8 crystal was obtained after heat treatment at above 630 °C of a sol–gel derived glassy material which has a chemical composition (mole ratio) 2BaO, TiO 2 , 2SiO 2 , and then the Ba 2 TiSi 2 O 8 films were formed from the hydration of CaO–P 2 O 5 glass powders. Heat treatment conditions and crystallization of the synthesized materials were studied by DSC-TG, XRD, and FT-IR. Second order nonlinear optical property has been verified by second harmonic generation test at 1064 nm. These results showed that the hydration process has a potential in rendering shape-comfortable optical materials.

This experiment was performed to investigate whether obovatol isolated from the leaves of Magnolia obovata has anxiolytic-like effects through GABA-benzodiazepine-receptors Cl(-) channel activation. The anxiolytic-like effects of obovatol in mice were examined using the elevated plus-maze and the automatic hole-board apparatus. Oral administration of obovatol (0.2, 0.5 and 1.0 mg/kg) significantly increased the number of open arm entries and the spent time on open arm in the elevated plus-maze test, compared with those of saline. Obovatol (0.2, 0.5 and 1.0 mg/kg) also produced anxiolytic-like effects, as reflected by an increase in head-dipping behaviors. These effects were comparable to those of diazepam (1.0 mg/kg), a well known anxiolytic drug. On the other hand, the anxiolytic-like effects of obovatol and diazepam were reversed by flumazenil, a benzodiazepine receptor antagonist, suggesting that the anxiolytic-like effects of obovatol were involved in GABA-benzodiazepine receptors complex. Obovatol was muscle relaxant by rota-rod test, but its effect was weaker than diazepam. Spontaneous locomotor activity also was inhibited by obovatol. Obovatol selectively increased the GABA(A) receptors alpha(1) subunit expression in amygdala of mouse brain. Obovatol also showed to bind to benzodiazepine receptors competitively in experiments using [(3)H]flunitrazepam in the cerebral cortex of mouse brain. Moreover, obovatol (10, 20 and 50 microM) increased Cl(-) influx and the increased Cl(-) influx was inhibited by flumazenil, in primary cultured neuronal cells and IMR-32 human neuroblastoma cells. These results suggest that obovatol has anxiolytic-like effects, and these pharmacological effects may be mediated by GABA-benzodiazepine receptors-activated Cl(-) channel opening.

A series of proton-conductive inorganic-organic hybrid membranes doped with phosphoric acid (H 3 PO 4 ) have been prepared by the sol-gel process with 3-glycidoxypropyltrimethoxysilane (GPTMS), 3-aminopropyltriethoxysilane (APTES), and tetraethoxysilane (TEOS) as precursors. High proton conductivity of 3.0 x 10 - 3 S/cm with a composition of 50TEOS-30GPTMS-20APTES-50H 3 PO 4 was obtained at 120°C under 50% relative humidity (RH). The differential thermal analysis curve showed that thermal stability of membrane is significantly enhanced by the presence of an SiO 2 framework up to 250°C. X-ray ray diffraction revealed that the gels were amorphous. Infrared spectra showed a good complexation of H 3 PO 4 in the matrix. The porous hybrid membrane, characterized by scanning electron microscopy, shows humidity-dependent conduction, and the conductivity under 75% relative humidity was significantly improved by addition of APTES due to the increase in the concentration of the defective site in the hybrid matrix.

Background Several reports have documented that Asians have a strong tendency to develop insulin resistance. The aims of this study were to evaluate the relative effects of insulin resistance and obesity on the risk factors for coronary heart disease (CHD) and to clarify whether insulin resistance accentuates these effects in apparently healthy men. Methods We conducted a cross sectional survey on 4,067 apparently healthy Korean men, aged between 20 and 83 years, with body mass indices (BMI) ranging from 15.19 to 40.29 kg/m2. The presence of insulin resistance was defined as a homeostasis model assessment (HOMA-IR) value >2.23, which is the cutoff for the highest decile in the normal BMI group (BMI

For usage of glass fertilizer, physical and dissolution properties were investigated according to variation of the SiO2 and K2O contents in silicate glasses. In glass forming region, K2O/P2O5 0-0.24, SiO2/(SiO2+P2O5) 0-0.29 and CaO/P2O5 0-1.00 were fabricated as clear glass in K2O-CaO-SiO2-P2O5 glass system. The glass transition temperature (Tg) and softening temperature (Ts) were gradually shifted to the higher temperature range according to increase of SiO2 contents. The K2O contents, which could cause the structure change from network structure to polymeric chain structure, have direct proportion with the thermal expansion coefficient and inverse proportion with Tg and Ts. The change of the K2O/P2O5 ratio was a main factor to control chemical durability and physical properties such as density and hardness. In the abnormal glass properties such as fast dissolution in aqueous solution, it was presented that the glass can be a good candidate for agriculture fertilizer.

The strength and durability of concrete are affected by various factors such as the quality of material, mixing ratio, construction, the method of cure, time elapsed. the condition of test and etc., it is very difficult to pre-estimate the strength of concrete with the use of experimental specimen. The domestic standard of specimen cylindrical type and its sizes are both l0cm20cm and 15cm30cm, which are prescribed in KS F2405, and the loading speed is prescribed to test with 2~3kgf/ per second. The loading speed should have great effect on the compressive strength, but in reality in the construction site sometimes the loading speed is applied so dubiously that the value of the compressive strength can be unreliable. And the cross sectional area of a specimen should be level and smooth, otherwise it can be broken at a lower stress than the real strength through the eccentric or intensive working of the load. Capping should be carried out in order to measure the strength correctly. And used for capping are various materials such as capping compound, cement glue, plaster, mechanical grinding and etc. In this study, therefore, I have carried out an experiment on the relationship among the loading speed, the ratio of height to diameter of specimen, the method of capping, and the compressive strength, for the efficient quality control of concrete structures. So this study has been purposed to provide some basic data that can be used effectively at construction sites.

Generally in real implementation of OFDM system, the simple and fast LS channel estimation method has been used for the wireless channel in the OFDM systems. If the wireless channel environment were mixed with RoF (Radio Over Fiber) channel, could we still use the conventional least square (LS) channel estimation method for proper communication? Therefore, in this paper, we analyzed that the performance of LS channel estimation where both wireless and RoF channel are coexisted in the OFDM based mobile communication system.

In this paper, we analyzed the available frame synchronization error ranges through the uncoded BER (bit error rate) performance in the condition of 64-QAM digital modulation in Mobile-WiMAX system.

This paper finds the optimum input bit size of FFT engine in WiBro system through the uncoded-BER performances of computer simulation.

Recently mobile IPTV service becomes primary service to boost sluggish IT industry. Also 3D image seems to be more prominent in broadcasting service. Therefore 3D image service over mobile IPTV service network will appear as key converging telecommunications and broadcasting service. In order to provide 3D image in wireless access network, it's necessary to enhance the capacity of wireless access network approximately 2 times, also operators should maximize the efficiency of radio resources usage ensuring QoS/QoE to users. But it's difficulty to enhance the radio capacity of wireless access network. Therefore it's necessary to use limited radio resource efficiently. In this paper 3D image transmission technology in mobile IPTV network is suggested to increase an ARPU in communication industry.

This paper proposes an efficient AGC scheme before mobile synchronization only using the existing hard-ware engine for AGC scheme after synchronization.

Polystyrene derivatives, poly[N-pvinylbenzyl-O-D-glucopyranosyl-(1-4)-D-glucoamide] (PV Maltose) and poly[N-p-vinylbenzyl-O-mannopyranosyl-(1-4)-D-glucoamide] (PV Mannose), which contain glucose and mannose moieties, respectively, have the specific binding ability with murine hematopoietic cells. In this study, we confirm the ability of these glycopolymers to interact specifically with human hematopoietic stem cells (HSCs) and mature cells derived from human cord blood (CB) and peripheral blood (PB). Using fluorescence isothiocyanate (FITC)-labeled glycopolymers, we observed that 98% to 93% of hematopoietic cells interacted very strongly with PV Mannose, and 63% of CB and 29% PB interacted with PV Maltose. Both glycopolymers bound better to cells from CB than from PB. Cytotoxic studies revealed that a 0.1 mM dose of PV Mannose induced apoptosis in 20% CB cells, in contrast to 3–5% PB cells. Furthermore, we demonstrated that all of CD34+ HSCs of both origins bound specifically to PV Mannose, whereas 33–47% bound to PV Maltose. In addition, the majority of B cells (CD19+), T cells (CD3+), monocytes (CD14+), and erythrocytes (CD235a+) bound to PV Mannose, but a lower percentage interacted with PV Maltose. In vivo study, bone marrow, spleen, and liver tissues in NOD-SCID mice injected with PV Mannose conjugated CB, were detected PV Mannose positive hematopoietic cells. These data suggest that the use of PV Mannose and PV Maltose might be used for gene and drug delivery for hematopoietic cells and thus, may be useful in therapeutic settings. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008

WiBro (wireless broadband), the standard of high-speed portable internet (HPI) based on OFDMA/TDD and IP network in Korea, is the subset of consolidated version of IEEE 802.16e wireless MAN standard. In this paper, the architecture and key physical layer technologies of WiBro are briefly introduced, whereas the convolutional turbo code (CTC) with high-order modulation is presented in detail. The performance of convolutional Turbo coded WiBro system with QPSK, 16QAM and 64QAM over ITU-R channel models is simulated, where pilot tones aided channel estimation and 1-tap equalization are applied. Simulation results show that the good BER performances of CTC with short code block size in WiBro systems, which facilitates the flexibility of channel resource allocation. Given the same code block size, CTC outperforms TC (turbo codes) and CC (convolutional codes).

Poly[N-pvinylbenzyl-O-D-galactopyranosyl-(1-4)-D-glucoamide], poly[N-pvinylbenzyl-O-D-glucopyranosyl-(1-4)-D-glucoamide], and poly[N-p-vinylbenzyl-O-mannopyranosyl-(1-4)-D-gluconamide] (referred to as PVLA, PVMA, and PV-Man) are polystyrene derivatives that contain galactose, glucose, and mannose moieties, which interact with hematopoietic cells (HCs). To clarify the specific interaction between the glucopolymers and hematopoietic cells, glycopolymers labeled with fluorescent isothiocyanate (FITC) were used to follow the specific interaction, which was visualized by confocal laser microscopy. We found that PV-Man binds strongly to HCs, probably because of a specific interaction mediated by specific receptors present on the cell membrane, while some cytotoxicity when was observed when PV-Man interacted with the cell membrane. The fluorescence intensity between PV-Man and HCs was up to four-fold (0.14 ± 0.04) that of PVMA and PVLA with hematopoietic HCs (0.033 ± 0.01). Moreover, cellular fluorescence increased significantly with increasing incubation time and increasing polymer concentration. Using hematopoietic lineage-specific antibodies, cells were stained and analyzed by flow cytometry to confirm which HCs showed specific binding with glycopolymers, especially hematopoietic stem cells and progenitor cells (c-kit+), B-lymphocyte progenitor cells (B220+), monocyte cells (CD11b+), and erythrocytes (Ter119+). © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007

The time-variation of channels during one OFDM symbol destroys the orthogonality among subcarriers and results in intercarrier interference (ICI), which may detail substantial error performance. Assumed channels vary in linear fashion during one OFDM symbol, we propose an iterative partial-ICI-cancellation (PIC) based detector for OFDM systems with linear modulation over doubly-selective Rayleigh fading channels. The tentatively detected information of channel and data are fed back to regenerate the ICI and then partially subtracted from the received signals. The optimal partial ICI cancellation factor (PICF) is determined by minimizing the mean square error (MSE) of data estimation. The proposed detector iteratively renews the channel estimation and data detection after PIC, and results in performance enhancement. Based on Jake's model for the Doppler effects, the bit error ratio (BER) performance of the proposed detector is illustrated for OFDM systems with phase-shift keying (PSK) and quadrature-amplitude modulation (QAM) in Rayleigh fading channels at several speeds.

In this paper high resolution transmission electron microscopy analysis is performed on indium gallium zinc oxide thin film transistors to determine the crystal structure of the material. The relative elemental concentrations of indium, gallium, zinc and oxygen were quantified and analyzed using energy dispersive spectroscopy before and after subjection to positive gate bias temperature stress at 80 °C. Notable changes in the concentration of oxygen in the device channel were observed along with a reduced concentration of the elements indium, gallium and zinc after electrical stressing. We speculate this relative reduction in metal concentration could be attributed to the outdiffusion of metal ions from the channel region into the surrounding thermal oxide and the increase in the oxygen concentration in the stressed device is related to electric field assisted adsorption of oxygen from the ambient.

Nonalcoholic fatty liver disease (NAFLD) comprises a large part of chronic liver diseases. Recently it was reported that adipokines are closely associated with the common risk factors for NAFLD, such as obesity, diabetes, dyslipidemia, and insulin resistance. We aimed to evaluate the changes in serum adiponectin, resistin and leptin concentrations related to alanine aminotransferase (ALT) elevations in Korean men with NAFLD.We studies 38 men who were diagnosed with fatty liver by abdominal ultrasonography. None had a history of excessive alcohol consumption, autoimmune hepatitis, inherited or metabolic liver disease or viral hepatitis. The subjects were divided into two groups. One group had normal levels of ALT (n=28) and the other had increased ALT (n=10). We compared anthropometrical parameters, biochemical items and serum adipokine levels between these two groups.Serum adiponectin levels were lower in the increased ALT group than in the normal ALT group (3.89 +/- 1.77 vs 7.01 +/- 2.54 microgram/dL, P=0.001). But there were no significant differences in serum leptin and resistin levels between two groups (4.02 +/- 2.04 vs 3.26 +/- 1.41 ng/mL, p=0.245, 80.14 +/- 14.8 vs 80.5 +/- 11.34 ng/mL, P=0.937, respectively). Multiple linear regression analyses demonstrated that the serum adiponectin level is inversely correlated with serum ALT level and that the serum aspartate aminotransferase (AST) level is positively correlated with the serum ALT level.Our study shows that hypoadiponectinemia is associated with an ALT elevation in patients with NAFLD. Adiponectin may play an indirect role in the development of NAFLD.

The paper proposes a practical method for AGC (automatic gain control) in an HPI (high-speed portable Internet) system. Downlink packets in this system consist of preamble symbols for AGC, AFC (automatic frequency control) and other purposes, and data symbols for traffic transmission. We compare the theoretical BER performance with the simulation one and produce an optimum parameter for AGC in this system. The proposed AGC method utilizes the preamble and requires a small amount of hardware. The validity of the proposed method is verified by computer simulation and real implementation.

For glass machining and laser-induced crystallization, a neodymium:yttrium aluminum garnet (Nd:YAG) laser was used. In the glass machining process, a laser drilled hole can be created by laser ablation with a transparent wavelength of 1064 nm. To create laser-induced silver metallic particles as seeds for nucleation in photosensitive glass containing Ag/sup +/ and Ce/sup 3+/ ions, the pulse width and frequency of the laser used were 8 ns and 10 Hz, respectively. Heat treatment was conducted at 570/spl deg/C for 1 h, following laser irradiation, to produce crystalline growth, after which a LiAlSi/sub 3/O/sub 8/ crystal phase appeared in the laser-irradiated Li/sub 2/O-Al/sub 2/O/sub 3/-SiO/sub 2/ glass. For the present study, we compared the effect of laser-induced crystallization on glass crystallization with that of spontaneous crystallization by heat treatment.

To investigate the origin of threshold voltage (Vth) shift of amorphous In?Ga?Zn?O (a-IGZO) thin-film transistors (TFTs), a combination of bias-temperature stress (BTS) and multi-frequency capacitance?voltage (C?V) measurements were used to evaluate the impact of oxygen partial pressure (PO2) during a-IGZO deposition on TFT electrical properties, electrical stability, and density of states (DOS). The extracted sub-gap DOS was decomposed into exponential bandtail states and Gaussian-like deep-gap states. The peak density of Gaussian-like states is larger for higher PO2. We conclude that the Gaussian-like states are excess/weakly-bonded oxygen in the form of O0 or O1? ions acting as acceptor-like states and are at the origin of TFT threshold voltage shift during positive BTS.

Background and Objectives:Recent studies have implicated inflammation as playing an important role in the occurrence, persistence and recurrence of atrial fibrillation and that C-reactive protein is a useful marker of the inflammation. The purpose of this study is to evaluate the association between serum CRP levels and the risk of atrial fibrillation. Subjects and Methods:This study was performed on 9,487 subjects (5,263 men and 4,224 women; mean age: 58.8±6.6 years) who underwent medical check-ups at the Health Promotion Center in Kanbuk Samsung Hospital. 9,438 normal control subjects and 49 atrial fibrillation patients were included in the study. The CRP was measured using a highly sensitive Behring Nephelometer II. Results:When comparing the two groups, there were significant differences in age, gender and the presence of hypertension and cerebrovascular accident, and these are the previously known risk factors for atrial fibrillation. After adjustment was made for the clinical significant variables of atrial fibrillation, multiple regression analysis revealed that the hsCRP levels were not associated with the risk for atrial fibrillation (p=0.52). Conclusion:The inflammatory markers (CRP, WBC count) were not predictive of a higher risk for atrial fibrillation in the Korean population. (Korean Circulation J 2005;35:309-314)