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An M-to-1 conveyor system consists of multiple upstream conveyors and a single downstream conveyor. In this paper, we investigate the paint batching problem on M-to-1 conveyor systems with the objective of minimizing setup costs. Our research is motivated by a vehicle re-sequencing problem at a major Korean automotive manufacturer. Setup costs are incurred when two consecutive jobs in the downstream conveyor do not share the same feature. Re-sequencing flexibility is limited by the precedence relationship among jobs in the upstream conveyors. First, we develop a mixed integer linear programming model and propose an efficient dynamic programming (DP) algorithm for a 2-to-1 conveyor system. However, because the suggested DP cannot guarantee optimality in general settings, we propose two efficient genetic algorithms (GAs) to find near optimal solutions. Specifically, we design the reordering operation for making offspring to satisfy the precedence condition. We show that the proposed GAs perform prominently with respect to optimality gap and computation time; thus, they are amenable to environments where solutions must be obtained within tight time constraints. HighlightsWe investigate the paint batching problem on M-to-1 conveyor systems with the objective of minimizing setup costs.We develop a mixed integer linear programming model for paint batching problem on M-to-1 conveyor systems.We propose an efficient dynamic programming (DP) algorithm for a 2-to-1 conveyor system.We suggest efficient two genetic algorithms for general M-to-1 conveyor systems.These algorithms are prominent in terms of computation time and optimality gap.

This study aimed to investigate the clinical and radiological findings in patients with transient global amnesia and to evaluate structural abnormalities using voxel-based morphometry. The subjects were diagnosed with transient global amnesia. For the voxel-based morphometry analyses, Statistical Parametric Mapping, running on the MATLAB platform (MathWorks, Natick, MA, USA), was employed to analyze the structural differences between patients with transient global amnesia and control subjects. Eighty patients met the inclusion criteria. Twenty-three patients (29%) were men, and 57 patients (71%) were women. There were significantly more women among the transient global amnesia patients compared with the general Korean population. MRI revealed hippocampal cavities in 41 patients (51%), and the incidence of such cavities was significantly different from that of the control subjects (24%). There were no differences in the clinical factors between the patients with and without hippocampal cavities. Diffusion-weighted imaging was performed in 54 patients, and 13 patients (24%) exhibited high signal intensity in the hippocampus. There were also no differences in the clinical factors between the patients with and without high signal intensities in the hippocampus on diffusion-weighted imaging. Twenty-six patients underwent three-dimensional volumetric T1-weighted imaging that produced results suitable for voxel-based morphometry, and these patients presented with gray matter volume reductions in the hippocampus, cingulum, and cerebellum. There were significant structural differences in the limbic structures between patients with transient global amnesia and the control subjects that might have contributed to vulnerability of the memory pathways of the patients with transient global amnesia.

We present an optimal test resource allocation strategy using uncertainty reduction in an environment where resource capacity changes dynamically according to engineering activity. The dynamics of test capacity change are modeled using a linear programming model and then extended and generalized to a Markov decision process. We analyze the model to develop structural results and illustrate its behavior with numerical examples. To the best of our knowledge, this model is the first to define, formalize, and analyze the decision-making process associated with reducing final test time in an environment where capacity may be dynamically increased, depending on engineering activity results.

Background: We evaluated the cortical morphology in patients with orthostatic intolerance. Methods: Thirty patients with orthostatic intolerance, as well as age- and sex-matched normal controls, were enrolled in this study. We divided the patients into orthostatic hypotension (n = 22) and postural tachycardia syndrome (n = 8) groups based on their response to a head-up tilt table test. We analyzed whole-brain T1-weighted MRI images using FreeSurfer 5.1. The measures of cortical morphology were compared between the groups. Results: The cortical thickness in the right hemisphere, including the medial orbitofrontal, peri-calcarine, post-central, inferior temporal, and lateral occipital cortex, and in the peri-calcarine cortex of the left hemisphere was thinned in patients with orthostatic hypotension compared to normal controls. The other measures of cortical morphology, including the surface area, volume, and curvatures, did not differ between patients with orthostatic hypotension and normal controls. However, none of the measures of cortical morphology differed between patients with postural tachycardia syndrome and normal controls. Conclusions: We demonstrated that the cortical morphology significantly changed in patients with orthostatic hypotension but not in patients with postural tachycardia syndrome compared to normal controls. These findings support the hypothesis that orthostatic intolerance is a heterogeneous syndrome.

BACKGROUND Tunnel misplacement is a common cause of failed anterior cruciate ligament (ACL) reconstruction. In this study, the accuracy of the femoral tunnel position was evaluated in robot-assisted ACL reconstruction using a magnetic resonance imaging (MRI)-based navigation system. We hypothesized that a difference of less than 2 mm between the planned femoral tunnel position and the created one was achievable. METHODS Four cadaveric knees underwent robot-assisted ACL reconstruction. A 3-dimensional model using pre-operative MRI images was used for preoperative planning, and a computed tomography (CT) scan was performed postoperatively. The planned and the created femoral tunnels were compared to assess the accuracy of the femoral tunnel position. RESULTS The distance between the intra-articular points of the planned and the created tunnels was 7.78 mm in the first experiment and 1.47 mm in the last one. The difference in tunnel length was 4.62 mm in the first experiment and 0.99 mm in the last one. CONCLUSIONS Accuracy of the femoral tunnel position improved with each robot-assisted ACL reconstruction using an MRI-based navigation system. In the last experiment, the accuracy of the femoral tunnel position was satisfactory.

Biomass burning is one of the significant emission source of PM and CO, but a few studies are reported in Korea. Air pollutants emission from biomass burning such as wood stove and boiler, and wood-pellet stove and boiler were estimated in this study. Activity levels related to biomass burning such as fuel types, amount of fuel loading, and location and temporal variation were investigated by field survey over Korea. Fuel loadings were 14.9 kg/day for wood stove, 31.3 kg/day for wood boiler, 12.8 kg/day for wood-pellet stove, 32.5 kg/day for wood-pellet boiler during the season of active use. These were mostly burned in winter season from october to april of next year. Estimated annual emissions from wood stove & boiler were CO 76,677, 710, 70, VOC 20,941, TSP 6,605, PM10 2,921, PM2.5 1,851, and NH3 7 ton/yr, respectively. Emissions from wood-pellet stove and boiler were CO 32,798, 1,830, 25, VOCs 5,673, TSP 629, PM10 457, PM2.5 344, and 2 ton/yr, respectively. When the emission estimates are compared with total emissions of the national emission inventory (CAPSS: Clean Air Policy Support System), Those occupy 12.5%, 2.8% of total national emission for CO and PM10, respectively. These results show wood and wood-pellet burning appliances were one of the major source of air pollution in Korea. In future, these types of heaters need to be regulated to reduce air pollution, especially in suburb area.

There have been various studies showing increased iron levels in parkinsonian disorders. The purpose of this study was to demonstrate topographical differences of brain iron deposition between progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple system atrophy (MSA-p) with SWI images.A total of 11 patients with PSP, 12 with MSA-p, 15 with Parkinson's disease (PD), and 20 age-matched healthy controls underwent SWI of the brain. Mean phase shift values of the red nucleus (RN), substantia nigra (SN), head of the caudate nucleus (CN), globus pallidus (GP), putamen (PUT), and thalamus (TH) were calculated and compared between groups. A voxel-based analysis of the processed SWI was performed to determine topographical differences of iron-related hypointense signals in PUT, GP, and TH.Patients with PSP and MSA-p had significantly higher levels of iron deposition than control and PD groups. Comparing patients with PSP and MSA-p, differences were found in iron concentrations of the RN, SN, GP, and TH, which were higher in the PSP group. However, iron levels in the PUT were higher in the MSA group (p0.05). The area under curve (AUC) indicated that the PUT was the most valuable nucleus in differentiating MSA-p from PSP and PD according to phase shift values (AUC=0.836). Meanwhile the GP (AUC=0.869) and TH (AUC=0.884) were the two most valuable nuclei in differentiating PSP from MSA-p and PD. Voxel-based analysis showed subregional differences in iron-related hypointense signals in the PUT, GP, and TH between MSA-p and PSP groups. Patients with MSA-p had significant increases of iron-related hypointense signals in the posterolateral PUT and adjacent lateral aspect of the GP, whereas the PSP group had increased hypodense signals in the anterior and medial aspects of the GP and TH.Our data demonstrate that pathological iron accumulations are more prevalent and severe in PSP compared to MSA-p. The distribution of high-iron-content regions in this study reflects pathoanatomically relevant sites. This finding allows for the use of MRI-based brain iron mapping as a technique to indirectly identify pathological changes.

Ischemic stroke is accompanied by structural deformation and functional deficits in the affected hemisphere. Within a couple of hours after symptom onset, the accurate identification of brain characteristics is critical to design the therapeutic strategies and it can potentially improve overall brain tissue viability by minimizing irreversible brain damage. In this study, white matter integrity and functional connectivity within 2-4h after right middle cerebral artery occlusion in rats were investigated using multimodal magnetic resonance imaging. During this stage, diffusion tensor image (DTI) revealed that fractional anisotropy along the ipsilesional external capsule was slightly increased as compared with preoperative baseline. Resting state functional MRI (rs-fMRI) showed that the inter-hemispheric functional connectivities from primary motor (M1), primary somatosensory of forelimb (S1FL), and barrel field (S1BF) seeds were considerably reduced at the hyperacute stage. Fractional amplitudes of low frequency fluctuations (fALFF) from rs-fMRI were significantly enhanced at the hyperacute stage in the frequency spectrum between 0.01 and 0.08Hz. In addition, the changes in fALFF were negatively correlated with the number of functionally connected voxels in M1, S1FL and S1BF. Our results suggest that these techniques are useful tools to evaluate remarkable brain changes in the hyperacute stage of ischemic stroke.

In this study we first explain details of the semiconductor manufacturing processes and cluster tools. Then we discuss the problems in current fab layout and cluster tool architecture. As a solution to these problems, we propose the ILE (In-Line EFEM) architecture in which wafer movements are conducted through interconnected EFEMs (Equipment Front End Modules) instead of AMHS (Automated Material Handling System). Then we model the pilot ILE system using discrete event simulation and analyze the cycle time. Finally we compare three different scenarios of equipment layout in the ILE system in terms of cycle time.

This paper discusses characteristics unique in the two-phase high-frequency-testing (HFT) environment in semiconductor manufacturing. We believe this paper is the first to define, formalize, and analyze the decision making problem associated with the two-phase HFT. Specifically, this paper defines the problem of minimizing the total HFT capacity usage by systematically finding the optimal number of preliminary HFT bin-1 chips subject to the main HFT, with the existence of the target service rate. We also propose a heuristic algorithm that exploits the special structure of the problem for efficiently obtaining a near-optimal solution. Finally, a numerical analysis and a case study have been conducted to gain more insights on the problem structure and the proposed algorithm.

Purpose: To evaluate the temporal and spatial resolution of magnetic resonance (MR) temperature imaging when using the proton resonance frequency (PRF) method combined with the keyhole technique. Materials and Methods: Tissue-mimicking phantom and swine muscle tissue were microwave-heated by a coaxial slot antenna. For the sake of MR hardware safety, MR images were sequentially acquired after heating the subjects using a spoiled gradient (SPGR) pulse sequence. Reference raw (k-space) data were collected before heating the subjects. Keyhole temperature images were reconstructed from full k-space data synthesized by combining the peripheral phase-encoding part of the reference raw data and the center phase-encoding keyhole part of the time sequential raw data. Each keyhole image was analyzed with thermal error, and the signal-to-noise ratio (SNR) was compared with the self-reference (nonkeyhole) images according to the number of keyhole phase-encoding (keyhole-data size) portions. Results: In applied keyhole temperature images, smaller keyhole-data sizes led to more temperature error increases, but the SNR did not decreased comparably. Additionally, keyhole images with a keyhole-data size of

This paper discusses scheduling characteristics unique in stacked chips [including multichip package (MCP) and multidie package (MDP)] production process such as reentrant work flow and synchronization constraint. It also proposes a modeling and analytical framework for stacked chips assembly operations, which is based on the formal framework of generalized stochastic Petri net. This approach allows the seamless integration of the logical and timed dynamics of stacked chip assembly operations in a single representation. Furthermore, the proposed framework supports the analytical representation of the stacked chips scheduling problem as a mathematical programming formulation, which can be effectively solved to optimality through enumerative techniques. The framework presentation and its capabilities are elucidated by detailed application on a small system configuration for MCP.

In this paper, we proposed a novel infrared absorbing structure for uncooled infrared detectors. The infrared absorber makes use of a quarter-wavelength structure composed of a dielectric layer, a protecting layer, an active layer, a supporting layer and a reflecting layer. Sputtered amorphous silicon is used as a dielectric layer because of its high refractive index. We fabricated the uncooled microbolometer with the proposed infrared absorbing structure by surface micromachining method. Then we characterized various bolometric properties such as thermal conductance, thermal time constant, responsivity and infrared absorptance. The fabricated bolometer showed the thermal conductance of 6.72 × 10 −7 W/K, the thermal mass of 4.43 × 10 −9 J/K, the thermal time constant of 6.6 ms and the responsivity of 7.76 × 10 3 V/W at 10 Hz chopper frequency and 9.22 μA bias current. From the results, the estimated absorptance is about 80%. We expect that the proposed absorbing structure shows high infrared absorption and high performance of uncooled microbolometer.

Structural reorganization in white matter (WM) after stroke is a potential contributor to substitute or to newly establish the functional field on the injured brain in nature. Diffusion tensor imaging (DTI) is an imaging modality that can be used to evaluate damage and recovery within the brain. This method of imaging allows for in vivo assessment of the restricted movements of water molecules in WM and provides a detailed look at structural connectivity in the brain. For longitudinal DTI studies after a stroke, the conventional region of interest method and voxel-based analysis are highly dependent on the user-hypothesis and parameter settings for implementation. In contrast, tract-based spatial statistics (TBSS) allows for reliable voxel-wise analysis via the projection of diffusion-derived parameters onto an alignment-invariant WM skeleton. In this study, spatiotemporal WM changes were examined with DTI-derived parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, DA; radial diffusivity, RD) using TBSS 2 h to 6 weeks after experimental focal ischemic stroke in rats (N = 6). FA values remained unchanged 2–4 h after the stroke, followed by a continuous decrease in the ipsilesional hemisphere from 24 h to 2 weeks post-stroke and gradual recovery from the ipsilesional corpus callosum to the external capsule until 6 weeks post-stroke. In particular, the fibers in these areas were extended toward the striatum of the ischemic boundary region at 6 weeks on tractography. The alterations of the other parameters in the ipsilesional hemisphere showed patterns of a decrease at the early stage, a subsequent pseudo-normalization of MD and DA, a rapid reduction of RD, and a progressive increase in MD, DA and RD with a decreased extent in the injured area at later stages. The findings of this study may reflect the ongoing processes on tissue damage and spontaneous recovery after stroke.

Survivors from cardiorespiratory arrest may develop neurologcal complications, such as post-hypoxic myoclonus (PHM). The hronic type of PHM is known as Lance–Adams syndrome (LAS), hich begins within days to weeks following an episode of anoxia 1]. LAS is characterized by myoclonus, which is triggered by intenional action or external stimuli and relieved at resting state or leep [1]. Several investigations have been performed to determine he pathogenesis of LAS. The loss of the neurotransmitter serotonin ithin the inferior olive has been believed to be an important causal actor for LAS, and gamma-aminobutyric acid may also be involved n the genesis of LAS [2–4]. Recently, neuroimaging has been used o detail the anatomical and pathophysiological basis of LAS [2,3]. evertheless, the pathogenesis of LAS has been not determined. We encountered a patient with LAS and performed resting state unctional MRI (rs-fMRI) to investigate the pathogenesis of LAS.

A surface micromachining uncooled infrared detector with an optimized vanadium alloy oxide layer is fabricated, based on low temperature annealing of V–W alloy oxide layer. Vanadium oxide is a promising material for an uncooled bolometer, due to its high temperature coefficient of resistance at room temperature. An infrared active layer is needed to be with the reflective layer to enhance its IR absorption. Test bolometers are successfully fabricated and then are radiated by an IR laser source at various power levels with a chopper in a frequency range of 1–500 Hz. The responsivity and the noise of the test bolometer are measured and the detectivity is calculated. From the results, the calculated detectivity is 1.1 × 107 cm Hz1/2 W−1. Bolometer detectivity can be increased further if the noise in the device is reduced.

In this work, we present novel fabrication and characterization of new bolometric material with high temperature coefficient of resistance (TCR) and low resistance for uncooled microbolometers. The new bolometric oxide thin film was fabricated based on vanadium–tungsten alloy and oxidation of the deposited alloy. The vanadium–tungsten alloy was formed by co-sputtering method and in order to improve uniformity of the film, vanadium–tungsten alloy target was used. The deposited vanadium–tungsten metal thin films with various tungsten concentrations were oxidized at 573 K for various times. Finally, for the application of the vanadium–tungsten-oxide to the microbolometer, we also performed some experiments concerning photolithography and etching. Fabricated bolometric film was resolved in water, so very thin SiNx layer, which deposited by plasma enhanced chemical vapor deposition was adopted as protecting layer and we established process condition for the patterning of vanadium–tungsten-oxide. As the results, we characterized material properties and bolometric properties such as TCR and noise. And we could successfully fabricate the new bolometric material with high TCR and good noise properties. So, the performance of a microbolometer may be improved with the use of this material.

In this paper, we proposed a microbolometer coupled with 3D feed horn antenna. It is a new device that enhances the performance of the microbolometer by coupling 3D horn shape antenna. We designed the optimum horn antenna size that has 20.08 dB directivity. And we designed the microbolometer as a circular shape in order to reduce the coupling loss between the horn antenna. We confirmed that the detectivity of the designed microbolometer would be improved as the noise characteristics of the microbolometer are enhanced by coupling feed horn antenna which acts as a cold shield. The detectivity of the designed 3D antenna-coupled microbolometer was improved about seven times more than that of the conventional microbolometer in state of background limited infrared performance. Fabrications of the microbolometer are carried out by a surface micromachining method. We achieved the thermally good isolated floating structure. And the 3D feed horn antenna was constructed by using a mirror-reflected parallel beam illuminator (MRPBI) system which is invented for rotating and tilted illumination. Using this method, we acquired the feed horn shape antenna mold. And we also acquired antenna plate by using PDMS injection method. Finally, to couple the antenna and the microbolometer, we proposed the PDMS injection bonding method.

We hypothesize that pre-existing susceptible structures in the brain may be associated with the development of newly diagnosed partial epilepsy of unknown etiology.Twenty-two patients with newly diagnosed partial epilepsy of unknown etiology and 36 healthy controls were enrolled in this study. In addition, we included 24 patients with chronic partial epilepsy of unknown etiology as a disease control group. We analyzed whole-brain T1-weighted MRIs using FreeSurfer 5.1. The volumes of the hippocampus, amygdala, thalamus, caudate, putamen, pallidum, brainstem, cerebellar gray and white matter, as well as cerebral gray and white matter were compared between the groups. We also analyzed the changes in brain volumes associated with the chronicity of epilepsy in the patients with chronic epilepsy compared to newly diagnosed epilepsy.The volume of cerebellar white matter in patients with newly diagnosed epilepsy was significantly smaller than that which was observed in the healthy controls (p=0.0001). This finding was also observed in patients with chronic epilepsy (p0.0001). Cerebral white matter volume was negatively correlated with the duration of epilepsy (r=-0.4, p=0.04).These findings support our hypothesis that cerebellar white matter changes may constitute a pre-existing susceptible structure in the brain that is associated with the development of partial epilepsy of unknown etiology. In addition, cerebral white matter was the structure that was the most vulnerable to the progression of epilepsy.

This paper presents a 32x32 microbolometer thermal imaging sensor for human body temperature measurement. Waferlevel vacuum packaging technology allows us to get a low cost and compact imaging sensor chip. The microbolometer uses V-W-O film as sensing material and ROIC has been designed 0.35-um CMOS process in UMC. A thermal image of a human face and a hand using f/1 lens convinces that it has a potential of human body temperature for commercial use.

It is a matter of debate whether increased brain iron levels are the cause or only the consequence of neurodegenerative process in degenerative parkinsonism. The aim of this study is to characterize disease-related changes in volumes and iron-related R2* values of basal ganglia and thalamus. 13 patients with progressive supranuclear palsy (PSP), 15 with a parkinsonian variant of multiple system atrophy (MSA-p), 29 with Parkinson’s disease (PD), and 21 age-matched controls underwent 3-Tesla MRI. The R2* values and volumes were calculated for the selected subcortical structures (caudate nucleus, putamen, globus pallidus, and thalamus) using an automated region-based analysis. Voxel-based analysis was also performed to visualize a topographical correlation of R2* value and volume. The PSP group had significantly higher R2* values in globus pallidus and caudate nucleus (p < 0.05), whereas the MSA-p group had higher R2* values in putamen (p < 0.001) than PD and controls. The globus pallidus in PSP and the putamen in MSA-p were the most significant areas of atrophy to differentiate PSP, MSA-p and PD (AUC = 0.856, 0.832, respectively, p < 0.001). The R2* values in both structures increased in parallel with the extent of atrophy. They were negatively correlated with volumes in putamen (r = −0.777, p < 0.001) and globus pallidus (r = −0.409, p = 0.025) of MSA-p, and globus pallidus (r = −0.4, p = 0.043) of PSP. Voxel-based analysis identified higher R2* values in more severely atrophic sub-regions in these structures. We observed topographical differences of iron deposition as well as atrophy between MSA-p and PSP. Increased iron levels were related to the structural atrophy in basal ganglia. Our results imply that iron accumulation is likely an epiphenomenon of the degenerative process.

In this study, we researched the emission source category and it was calculated emissions estimates from existing research or literature review related to port. In addition, we have created the basis for a policy that can reduce greenhouse gas emissions calculation based on the results of the harbor. Greenhouse gas emissions estimation results, we proposed a method for allocating the GIS space. In this study, we confirmed based on the calculated greenhouse gas emissions by sources resulting in the GIS Map Port result of the expression construct for space allocation. Based on these results, it tries to provide the basic data that can be used when you want to create a local government measures to reduce scenario in the future.

In this work, high-performance uncooled microbolometer was fabricated by using vanadium tungsten oxide as a infrared-sensitive material and its bolometric properties was characterized. As a bolometric material, the optimized V0.95W0.05Ox thin film has a high TCR value over - 3.0%/K and low noise properties compared with VOx thin film. The fabricated V0.95W0.05Ox-based microbolometer was vacuum-packaged and equipped with thermal electric cooler for the measurement of bolometric properties. The TCR value of the fabricated device was -3.49%/K at room temperature resistance of 71 kOmega and the measured thermal conductance was 6.1times10-7 W/K. Finally, we obtained high responsivity over 1.8times104 W/K and high detectivity over 1.3times109 cmHzfrac12/W at a chopper frequency of 10 Hz and a bias current of 7.4 muA

We propose a versatile infrared (IR) absorbing structure for uncooled infrared detectors. We have designed an infrared absorber consisting of five thin film layers (dielectric layer/protection layer/active layer/supporting layer/reflecting layer) that produce a quarter-wavelength resonance condition. It has excellent thermal properties, which are not influenced by the deformation of the thermal isolation structure. We fabricated a microbolometer with the proposed IR absorption structure by a surface micromachining technology. We estimated an IR absorptance of 80%. This IR absorption structure can be applied to both surface micromachining and bulk micromachining.

Purpose: This study was designed to examine the effects of a weight control program on body weight and the sense of efficacy for control of dietary behavior in psychiatric inpatients. Methods: A quasi-experimental design was used. Data were collected from March 1 to September 30, 2007. Female mentally ill patients in closing psychiatry ward of H University Hospital participated in the study (16 persons in the experimental group and 13 in the control group). Results: The weight control program including diet therapy, exercise, education and behavior modification therapy decreased the rate of weight gain in female mentally ill patients taking atypical antipsychotics, and effectively increased a sense of efficacy for control of dietary behavior. Conclusion: Weight control program had a positive effect as a nursing intervention to decrease obesity and to increase the sense of efficacy for control of dietary behavior of psychiatric inpatients in psychiatric inpatients.

To produce a highly sensitive uncooled microbolometer, the development of a high-performance thermometric material is essential. In this work, amorphous vanadium–tungsten oxide was developed as a thermometric material at a low temperature of 300°C, and the microbolometer, coupled with the material, was designed and fabricated using surface micromachining technology. The vanadium–tungsten oxide showed good properties for application to the microbolometer, such as a high-temperature coefficient of resistance of over −4.0%∕K and good compatibility with the surface micromachining and integrated circuit fabrication process due to its low fabrication temperature. As a result, the uncooled microbolometer could be fabricated with high detectivity over 1.0×109cmHz1∕2∕W at a bias current of 7.5μA and a chopper frequency of 10–20Hz.

A three-dimensional feed-horn antenna for the 10-microm-wavelength infrared region has been suggested, characterized, and fabricated. It is applied to an infrared detector for efficient collection of infrared radiation and to reduce background noise. The optimum size of the horn antenna was designed for maximum antenna directivity. The three-dimensional feed-horn antenna mold was fabricated by rotating and tilting illumination, whereas the antenna plate was acquired through electroplating. Antenna characteristics were measured by coupling of the antenna with a microbolometer. Measurement results show that the directivity of the antenna is 16.1 dB and the background noise is reduced by a factor of approximately 2 compared with an open-structure infrared detector.

Multilayer VOx films are reported to improve the infrared (IR) detecting characteristics for application as an IR active layer in a microbolometer. Multilayer VOx films formed from the V2O5/V/V2O5 thin film structure showed some advantages in electrical property control and more effective formation of typically unstable vanadium oxide phases. These phases are difficult to achieve by single-layer VOx film fabrication with conventional reactive sputtering. Multilayer VOx films were fabricated by low temperature oxygen annealing at 300 °C after the alternating deposition of stable V and V2O5 layer using rf sputtering. The electrical measurement and microstructural analysis of annealed films were performed to evaluate the advantage of multilayer VOx film fabrication. Owing to the well-controlled mixed phase formation, including V2O3, VO2, and V2O5 in the annealed V2O5/V/V2O5 multilayer film, the temperature coefficient of resistance value and resistivity of the new multilayer VOx film could be increased up to...