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A very thick single-armor material is generally used for bulletproof performance in combat vehicles; as a result, the combat capability is greatly reduced by the heavy weight. The armor plate of a combat vehicle is manufactured by applying a welding process to the joints of high-hardness steel. However, when applying the welding process to the high-hardness armor plate, the hardness decreases owing to hot softening in the heat-affected area, resulting in deterioration of the bulletproof performance. In this study, three different welding materials were selected, and their weld strengths were evaluated according to the TACOM standard. The mechanical properties and microstructures of the welded parts of the three materials were analyzed through tensile, bending, impact, and hardness tests. Finally, the most suitable welding material was selected for the high-hardness armor plate.

Welding is widely used for joining steel components in the automobile industry. With the use of high-quality materials, welding defects began to become increasingly complex. Immobilized oxide is one of the recent complex defects. Immobilized oxide defects generated in gas metal arc welding (GMAW) of high-strength steel and high-strength galvanized steel result in unpainted part on the surface of welding beads. Thus, it is necessary to be eliminated by using grinding and peening. However, it is difficult to find where oxides generate and how oxides generate in order to eliminate it. Few studies have explored the mechanism of immobilized oxide formation in other fields so far. In this study, the generation patterns of oxide defects were confirmed. Further, an oxide defect monitoring system for GMAW was developed by using an infrared camera and image processing equipment. The chemical properties of the immobilized oxide were verified by performing energy dispersive spectroscopy (EDS). The oxide appeared to be brighter in the infrared image, and then, image processing was conducted to determine the boundary of oxide defects. The processed images were laid over the original images, and the oxide defect area was displayed on the monitoring panel. Patterns of oxide defect generation were confirmed when it was combined with the following molten pool area moving in the opposite direction of the welding direction in our results. The developed monitoring system can be easily applied to the automatic welding process in the automobile industry.

Arc plasma flow between electrodes has been investigated in several studies. However, in the industrial field, arc plasma flow between electrodes is hindered by interfering materials such as filler metal in arc welding, substrates in chemical vapor deposition, and powders in sintering. Therefore, in this study, high temperature arc plasma flow analysis via three obstruction structure shapes was performed to understand the inter-electrode interference phenomena. COMSOL Multiphysics was used for the analysis; COMSOL interface such as electric field, magnetic field, heat transfer, and fluid flow (laminar flow) was applied and Multiphysics such as plasma heat source and temperature coupling were considered. The temperature and velocity of the arc plasma were determined and the energy transfer between the electrodes was analyzed. We confirmed that the concave shape has a lower average heat flux than the other shapes, with the arc pressure evenly distributed in the anode. It is concluded that the concave shape can reduce the flow of the plasma from the anode and obtain even distribution of the arc plasma in the radial direction.

Several industries including the automotive industry have recently applied the process of welding high-strength steel for their requirements. Ultra-high-strength steel is harder than normal high strength steel; it is considerably much stronger and stiffer. In particular, ultra-highstrength steel (UHSS) can be formed in pieces that can be up to 10 to 15% thinner than normal steel without sacrificing strength, which enables weight reduction and improved fuel economy in automobiles. Furthermore, UHSS can be formed into complex shapes that can be welded into structural areas. This study is based on previous experiments and is aimed at establishing the maximum allowable vertical and longitudinal loads for stitch-welded ultra-high-strength steel in laser-arc hybrid welding. Research on the stress distribution and maximum allowable load and for stitch-welded ultra-high-strength steel is conducted via Solid-Works, a program that analyzes the stress of a virtual model. We determine that the maximum allowable load and stress distribution vary depending on the shape of the welded lap joint. The effects of the stress distribution and maximum allowable load on stitch-welded ultra-high-strength steel can be utilized as a standard for high energy welding of ultra-high-strength steel, and we can further predict fault regions in the stitch-welded.

Manufacturing processes of industrial tire are composed of mixing, extrusion, curing, trimming and inspecting. Among them curing is the most important process in the production of industrial tire. In this study the newly developed spring vent system was designed in order to solve rubber intrusion problem inside spring vent system in the curing process. After the experiment it is concluded that rubber intrusion was caused by angled stem head part. New spring vent system was manufactured and new design of spring vent system is proper to use for industrial tire curing process.

Fishing boats more than 5 tons is obliged to VHF DSC by Fishing Vessels Act and Vessel Safety Act. The owner of the fishing vessel is equipped to the automatic position reporting device in accordance with the Notice of the Minister of Land, Transport and Maritime Affairs to regulations, shall be ensure to navigations safety and in order to respond quickly in the event of maritime accidents on fishing vessels. East sea set up to start in 2012, which is now underway the annual install plain to the yellow sea and the south sea for VHF coast stations. It is web-based remote operation of DSC on the remote control and monitoring in Fishery Information Communication Station for the coastal VMS construction project. All fishing vessels is VHF DSC in conjunction with the GPS that location information transmitted to the coast station. automatically by the DSC call. This paper has been studied on the communications coverage set up and traffic operation for realization a roaming service by navigation route tracking and RSSI techniques in parallel algorithm refer to VHF DSC coast stations in east sea.

Outbreak of animal infectious diseases such as foot-and-mouth disease, avian influenza are becoming prevalent worldwide. For prevent the further infection, tremendous numbers of the infected or culled stocks are buried around farm. This burial method can generate a wide range of detrimental components such as leachate, nutrient, salt, and pathogenic bacteria, consequently. In this study, for the stabilization of livestock carcasses leachate, advanced oxidation processes utilizing the Fenton reaction was investigated in lab-scale experiments for the treatment for CODCr of livestock carcass leachate. CODCr reduction by the Fenton oxidation was investigated response surface methodology using the BoxBegnken methods were applied to the experimental results. A central composite design was used to investigate the effects of the independent variables of pH (x1), dosage of FeCl2· 4H2O (x2) and dosage of H2O2 (x3) on the dependent variables CODCr concentration (y1). A 1 M NaOH and H2SO4 was using for pH control, FeCl2·4H2O was used as iron catalyst and NaOH was used for Fenton reaction. The optimal conditions for Fenton oxidation process were determined: pH, dosage of FeCl2·4H2O and dosage of H2O2 were 3, 0.6 g (0.0151 M) and 7 mL(0.259 M), respectively. Statistical results showed the order of significance of the independent variables to be pH > initial concentration of ferrous ion > initial concentration of hydrogen peroxide.

Objective To observe the contrast spread in superoposterior transforaminal epidural steroid injection (SP TFESI) and investigate the correlation between spread patterns and efficacy. Methods Thirty-one patients with lumbosacral radiculopathy underwent single-level TFESI under fluoroscopy. The final needle tip position was targeted toward the SP quadrant of the intervertebral foramen. To observe the spread, 1 mL of contrast material was injected, followed by a steroid injection. The contrast spread was graded anteroposteriorly and vertically in the epidural space. The effect of SP TFESI was evaluated by proportional pain score reduction. Results Levels injected were L4-5 (n=20) and L5-S1 (n=11). Seventeen cases were lateral, and 14 were central herniated disc (HD). Baseline mean visual analog scale score was 6.23. Contrast dispersed dorsally in all the cases, and 45.2% cases showed a concurrent ventral spread. The proportion of the pain reduction after 2 weeks showed no difference between the two groups. In vertical spreading analysis, mean cephalic/caudal grades were 1.40/1.55 at L4-5 level and 1.73/1.64 at L5-S1 level. The HD location had no effect on contrast dispersion. Conclusion In SP TFESI, ventral contrast spread did not guarantee a better effect; however, the extent of cephalic flow in ventral expansion group correlated with the proportion of pain reduction.

Mg2+-modified zeolites (MMZs) were used for the adsorption of NH4 +-N and Esherichia coli at different concentrations for a batch experiment. The adsorption characteristics (i.e. kinetics, isotherms, and mechanisms) of NH4 +-N and E. coli on natural zeolites and MMZs were studied. Simple kinetic models, including pseudo-first-order kinetic models and pseudo-second-order kinetic models, were used to model the adsorption mechanism. Adsorption of NH4+-N and E. coli followed a pseudo-second-order kinetic model with the pseudo-second-order kinetic constants (k 2 ) increasing with an initial increase in NH4 +-N and E. coli concentrations. An intraparticle diffusion model was also used to investigate the mechanism of adsorption. From the intraparticle diffusion model results, NH4 +-N and E. coli adsorption onto natural zeolites and MMZs could be described via film diffusion followed by particle diffusion. Furthermore, film diffusion was the rate-determining step in NH4 +-N adsorption and particle diffusion was the rate-determining step in E. coli adsorption on natural zeolites and MMZs in this study. The maximum adsorption of NH4 +-N and E. coli onto MMZs was 7.759 and 0.175 mg/g, respectively. Greater E. coli adsorption onto MMZs was due to the unique surface properties of the material compared with natural zeolites. Electrostatic interactions and hydrophobic attractions simultaneously affected the adsorption of E. coli onto MMZ in this study. Therefore, MMZ can be an efficient adsorbent material for the simultaneous removal of NH4 +-N and E. coli from carcass leachates.

A general synthetic method of carotenoid natural products has been developed, in which the systematic chain extension and termination processes were applied. The syntheses of the chain extension and termination units were greatly improved by the use of the common intermediate, 1-bromo-4-chloro-3-methyl-2-butene ( 8 ), in a short and highly efficient way. The C 10 chain initiation β-cyclogeranyl sulfone ( 3 ) was coupled with the C 5 chain extension unit to give the C 15 chain-extended allylic sulfone after chemoselective sulfide oxidation. This chain-extended C 15 allylic sulfone underwent the Julia olefination reaction with the C 5 and the C 10 chain termination units to give retinol ( 1 ) and β-carotene ( 2 ), respectively.

Bromination of 4 by PBr 3 under Cu 1 catalyst produces the ambidextrous allylic halide 5 regioselectively and stereoselectively. Hetero nucleophiles distinguish the allylic carbon containing Br from the one containing Cl in 5 to give the heteroatom-substituted C 5 allylic chloride 3. The Julia olefination reaction with the C 1 5 sulfone 2 provides diverse retinyl ethers 1.

An efficient synthetic method for the allylic sulfone 2 containing a conjugated triene moiety has been proposed involving i) coupling of allylic sulfones 4 with the C5 bromoallylic sulfide 5, ii) base-promoted dehydrosulfonation in the presence of allylic sulfide, and iii) selective oxidation of the resulting trienyl sulfide to the corresponding sulfone. Total synthesis of lycopene starting from the C15 allylic sulfone 2b has been described, where the new C10 bis(chloroallylic) sulfone 11 proved to be a useful substitute for the C10 bis(chloroallylic) sulfide 3, which did not require the problematic chemoselective sulfur oxidation in a conjugated polyene.

Several industries including the automotive industry have recently applied the process of welding high strength steel. High strength steel is steel that is harder than normal high strength steel, making it much stronger and stiffer. HSS can be formed in pieces that can be up to 10 to 15 percent thinner than normal steel without sacrificing strength, which enables weight reduction and improved fuel economy. Furthermore, HSS can be formed into complex shapes that can be welded into structural areas. This study is based on previous experiments and is aimed at establishing the stress distribution for laser welded high strength steel. Research on the stress distribution for laser welded high strength steel is conducted by using Solid Works, a program that analyzes the stress of a virtual model. In conclusion, we found that the stress distribution is changed depending on the shape of welded lap joint. In addition, the Influence of the stress distribution on welded high strength steel can be used to standard for...

Objective To evaluate the risk of phrenic nerve injury during ultrasound-guided stellate ganglion block (US-SGB) according to sonoanatomy of the phrenic nerve, and determine a safer posture for needle insertion by assessing its relationship with surrounding structure according to positional change. Methods Twenty-nine healthy volunteers were recruited and underwent ultrasound in two postures, i.e., supine position with the neck extension and head rotation, and lateral decubitus position. The transducer was placed at the anterior tubercle of the C6 level to identify phrenic nerve. The cross-sectional area (CSA), depth from skin, distance between phrenic nerve and anterior tubercle of C6 transverse process, and the angle formed by anterior tubercle, posterior tubercle and phrenic nerve were measured. Results The phrenic nerve was clearly identified in the intermuscular fascia layer between the anterior scalene and sternocleidomastoid muscles. The distance between the phrenic nerve and anterior tubercle was 10.33±3.20 mm with the supine position and 9.20±3.31 mm with the lateral decubitus position, respectively. The mean CSA and skin depth of phrenic nerve were not statistically different between the two positions. The angle with the supine position was 48.37°±27.43°, and 58.89°±30.02° with the lateral decubitus position. The difference of angle between the two positions was statistically significant. Conclusion Ultrasound is a useful tool for assessing the phrenic nerve and its anatomical relation with other cervical structures. In addition, lateral decubitus position seems to be safer by providing wider angle for needle insertion than the supine position in US-SGB.

Major depressive disorder and alcohol dependence are common and serious mental illnesses. There is a great interest in discovering useful treatments for both mood symptoms and alcohol abuse in those patients with depressive disorders and comorbid alcohol dependence. The primary purpose of this study was to evaluate the effectiveness and tolerability of mirtazapine for the treatment of patients with alcohol dependence comorbid with a depressive disorder in an open label, naturalistic multicentre treatment setting. The 17-item Hamilton Depression Rating Scale (HDRS), the Hamilton Anxiety Rating Scale (HARS) and the Clinical Global Impression-Severity (CGI-S) scale were measured at baseline and at weeks 4 and 8 for the assessment of treatment effectiveness. Alcohol craving was measured using the Obsessive Compulsive Drinking Scale (OCDS) and the Visual Analog Scale for Craving (VAS). This study showed a statistically significant reduction of the scores on the HDRS (13.9+/-7.3, p