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The dark current of long wavelength infrared (LWIR) detector should be reduced to improve performance and decrease the system size, weight and power consumption (SWaP). In this work, we present the process to reduce the dark current of T2SL LWIR detector with nBn structure. The nBn structure consists of InAs/GaSb 14/7 monolayers (MLs) contact layer and absorber separated by Al0.2Ga0.8Sb barrier. For T2SL LWIR detector, the barrier structure is often used to reduce the dark current and passivate absorber. However, the barrier itself is very fragile and easily damaged during the device process. The proposed process was developed so that Al0.2Ga0.8Sb barrier is not damaged by any solution from the isolation etch process to the passivation process. In this process, CHF3 plasma treatment after the isolation etch with ICP reduced significantly the dark current. We attribute this to damage reduction of Al0.2Ga0.8Sb barrier by CHF3 plasma treatment. The 15 μ m pitch devices fabricated with optimal process conditions showed the dark current density of less than 2.0 × 10−5 A/cm2 at −0.3 V and 80 K.

Particulate respirators have been used in both general environments and in the workplace. Despite the existence of certified respirators for workers, no strict regulations exist for masks worldwide. The aims of this study were to evaluate the filter efficiency of various mask types using the Korean Food and Drug Administration (KFDA) [similar to the European Union (EU) protocol] and the National Institute for Occupational Safety and Health (NIOSH) protocol and to compare the test results. We tested a total of 44 mask brands of four types (anti-yellow sand, medical, quarantine, general) and handkerchiefs with a TSI 8130 Automatic Filter Tester. A wide variation of penetration and pressure drops was observed by mask types. The overall mean penetration and pressure drop of all tested masks were respectively 35.6 ± 34.7%, 2.7 ± 1.4 mm H2O with the KFDA protocol, and 35.1 ± 35.7%, 10.6 ± 5.88 mm H2O with the NIOSH protocol. All tested quarantine masks satisfied the KFDA criterion of 6%. Six-ninths and four-sevenths of the anti-yellow sand masks for adults and children satisfied the criterion of 20%, respectively. Medical masks, general masks, and handkerchiefs were found to provide little protection against respiratory aerosols.

Purpose: Though prompt diagnosis to minimize symptom duration (SD) is highly associated with organ salvage in cases of testicular torsion (TT), SD is subjective and hard to determine. We thus investigated the clinical implications of systemic in-flammatory responses (SIRs) as potential surrogates of SD to improve testis survival. Materials and Methods: Sixty men with TT that underwent immediate operation among orchiectomy and orchiopexy follow-ing a visit to a single emergency department were retrospectively enrolled. Mandatory laboratory tests conducted included neutrophil, lymphocyte, and platelet counts. Results: Mean age and SD was 15.7±3.7 years and 8.27±4.98 hours, respectively. Thirty-eight (63.3%) underwent orchiec-tomy and the remaining 22 underwent orchiopexy. Leukocytosis (p=0.001) and neutrophil-lymphocyte ratio (NLR, p

Although high productivity is possible, cold forged helical gears have not been widely used due to difficulty in achieving mechanical properties as well as dimensional accuracy of the product. Confidence in the gear characteristics also is very important in heavy-duty gear applications. Therefore, the properties of forged gears must be compared to the properties of conventional machined gears. The properties might be different due to the different fabrication processes. In this study, machined and forged products both before and after heat-treated have been compared by measuring the residual stress and involute curve of the tooth. Characteristics of hardness and microstructure were also compared. Additionally, tooth fracture strength was compared for the heat-treated products. Moreover, the tooth strength and the fracture pattern were compared between the machined and forged gears. The forged gear showed decreased changes in residual stress and decreased changes in dimensions when compared to the machined gear before and after heat treatment. The forged gear was over 10% better than the machined gear in tooth strength.

Four types of Mg–5Al alloy with various weight percentages of Sr ranging from 0 to 1.5 wt% were examined using electrochemical techniques and surface analyses. The electrochemical results indicated that the Mg–5Al alloy containing Sr to have a higher pitting potential and impedance than the Mg–5Al specimen with highest value being observed in the Mg–5Al–1Sr specimen. Sr addition induced the continuous precipitation of Al–Sr phases along with grain refinement and increased the formation of an Al(OH) 3 film on the surface.

A sandwich panel which is comprised of truss cores faced with solid face sheets is lightweight and multi-functional. So it is widely used to not only structural material but also heat transfer media in transportation field such as airplane, train and vessel. There are various core topologies such as pyramidal and tetrahedral truss, square honeycombs and kagome truss. The study focused on analytical approach to optimize compression and shear quality of the unit cell of PCM with pyramidal configuration. With various unit cell models which have the same core weight per unit area but different truss member angle, analytical solution for effective stress (), peak stress () by yielding and buckling, relative density () and effective stiffness () have been computed and compared each other. With this approach, the most optimal core configuration was predicted. The result has become the efficient guidelines for the design of PCM core structure.

The corrosion properties of four Mg–5Al-based alloys with rare earth alloying elements (calcium, misch-metal and strontium) in a 0.01 M alkaline NaCl solution were examined using electrochemical tests and surface analyses. The electrochemical tests indicated that the addition of 1% rare earth improved the pitting potential, film formation and charge transfer resistance of the Mg–5Al specimens. Moreover, the addition of 1Sr produced the best corrosion resistance due to the continuous precipitation of Mg/Al-rare earth compounds as a corrosion barrier.

The effect of mischmetal (Mm) on the corrosion properties of Mg–5Al alloy was investigated by electrochemical techniques in 0.01 M NaCl solution as the alkaline condition (pH 12) and surface analyses. The electrochemical tests indicated that the pitting potential, time to pitting initiation, and charge transfer resistance of the Mg–5Al specimens increased with increasing Mm content. Surface analyses indicated that Mm promoted the formation of passive film in the absence of Mm products. In addition, the benefits of Mm addition are the refinement of the precipitates and reduction in grain size.

The sensing system was designed and fabricated to investigate the ferment environment of soybeans. gas was saturated after about 7 h and gas was reached the peak after about 8 h in the inoculation of Bacillus subtilis. However, times that gas and gas were reached maximum value without Bacillus subtilis were about 15 h and 18 h, respectively. The sample that inoculated Bacillus subtils had deeper taste than one without it. We found that the peak time of gas means the starting time of fermentation. If we control the operating time after the start of fermentation, it is expected to make a suitable Chungkukjang to individual preference.

A novel method for direct, high precision mass measurements of relativistic exotic nuclei has been successfully applied in the storage ring ESR at GSI. The nuclei of interest were produced by projectile fragmentation of 930 MeV / u bismuth ions, separated in-flight by the fragment separator FRS, stored and cooled in the ESR. The mass values have been deduced from the revolution frequencies of the coasting cooled ions. We have measured 104 new mass values with a precision of about 100 keV and a resolving power of 3.5×10 5 for the neutron-deficient isotopes of the elements 57≤Z≤84 . This paper presents the experimental method, the mass evaluation and a table of the experimental mass values.

Recent results of mass measurements of exotic heavy nuclei using Schottky mass spectrometry are reported. The investigated nuclei were produced and separated by the fragment separator FRS, injected, stored and cooled in the experimental storage ring ESR. Their masses were determined from the frequency analysis of the beam noise. In the present experiment the masses of more than 150 proton-rich nuclei in the mass region A ∼- 200 have been determined for the first time. Representative results are given for proton-separation energies and shell corrections. For some elements the proton drip line can be determined.

High-precision mass measurements of proton-rich isotopes in the range of 60{le}Z{le}84 were performed using the novel technique of Schottky spectrometry. Projectile fragments produced by {sup 209}Bi ions at 930{ital A} MeV were separated with the magnetic spectrometer FRS and stored and cooled in the experimental storage ring (ESR). A typical mass resolving power of 350000 and a precision of 100keV were achieved in the region A{approx}200 . Masses of members of {alpha} chains linked by precise Q{sub {alpha}} values but not yet connected to the known masses were determined. In this way it is concluded that {sup 201}Fr and {sup 197}At are proton unbound. {copyright} {ital 1997} {ital The American Physical Society}

The aim of the present investigation is to correlate the change of tensile yield strength with the dislocation structure of Fe-23Al and Fe-30Al alloys tested at room and high temperatures. The results showed that the yield strength of Fe-23Al alloy increased with increasing the quench and test temperatures. This was mainly attributed to the increase in the partition of imperfect superdislocations, leaving NNN and NN type APB trails behind during the deformation. In Fe-30Al alloy, the yield strength increased with increasing the test temperature, but decreased with increasing the quench temperature. The lower yield strength of the specimen quenched at 500 ° C was thought to be due to relatively lower NNN APB energy. It is considered that the yield strength of Fe-30Al alloy is governed by two competing factors; the partition of perfect and imperfect variants of dislocations and the shear stress required for the dislocation movement.

A Smith-Purcell radiation source using a grating structure modified in a cylindrical manner was considered to utilize a high power relativistic annular electron beam. The output characteristics were confirmed by numerical simulations assuming a 500 keV-5 kA electron beam. The experiment is being prepared.

The main function of the ITER blanket shield block (SB) is to provide nuclear shielding and support the first wall (FW) panel. It needs to accommodate all the components located on the vacuum vessel (in particular the in-vessel coils, blanket manifolds and the diagnostics). The conceptual, preliminary and final design reviews have been completed in the framework of the Blanket Integrated Product Team. The Korean Domestic Agency has successfully completed not only the final design activities, including thermo-hydraulic and thermo-mechanical analyses for SBs #2, #6, #8 and #16, but also the SB full scale prototype (FSP) pre-qualification program prior to issuing of the procurement agreement. SBs #2 and #6 are located at the in-board region of the tokamak. The pressure drop was less than 0.3 MPa and fully satisfied the design criteria. The thermo-mechanical stresses were also allowable even though the peak stresses occurred at nearby radial slit end holes, and their fatigue lives were evaluated over many more than 30 000 cycles. SB #8 is one of the most difficult modules to design, since this module will endure severe thermal loading not only from nuclear heating but also from plasma heat flux at uncovered regions by the FW. In order to resolve this design issue, the neutral beam shine-through module concept was applied to the FW uncovered region and it has been successfully verified as a possible design solution. SB #16 is located at the out-board central region of the tokamak. This module is under much higher nuclear loading than other modules and is covered by an enhanced heat flux FW panel. In the early design stage, many cooling headers on the front region were inserted to mitigate peak stresses near the access hole and radial slit end hole. However, the cooling headers on the front region needed to be removed in order to reduce the risk from cover welding during manufacturing. A few cooling headers now remain after efforts through several iterations to remove them and to optimize the cooling channels. The SB #8 FSP was manufactured and tested in accordance with the pre-qualification program based on the preliminary design, and related R&D activities were implemented to resolve the fabrication issues. This paper provides the current status of the final design and relevant R&D activities of the blanket SB.

ESD-induced latent damage in CMOS integrated circuits has been thoroughly investigated after cumulative low-level ESD stress. A study of the latent damage for transistors at the package level has been performed with various kinds of ESD stress modes. The impact of latent damage on circuit performance degradation was also evaluated using a 64 Mb DRAM chip as a DUT.

Secondary beams from fragmentation of $^{58}\mathrm{Ni}$ have been produced with energies of $(200\ensuremath{-}220)A$ MeV, separated with a fragment separator and injected into a storage-cooler ring for half-life measurements. The relative momentum spread $\frac{\ensuremath{\Delta}p}{p}\ensuremath{\approx}1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ (FWHM) which we achieved allowed us to resolve the ground and isomeric states of cooled $^{52}\mathrm{Mn}$ and $^{53}\mathrm{Fe}$ nuclei in the measured mass spectra. The circulating beams were fully ionized, which rendered it possible to measure pure ${\ensuremath{\beta}}^{+}$ branches for $^{52g}\mathrm{Fe}$ and $^{53g}\mathrm{Fe}$ and the sum of pure ${\ensuremath{\beta}}^{+}$ and $\ensuremath{\gamma}$ branches in the decay of the isomers $^{52m}\mathrm{Mn}$ and $^{53m}\mathrm{Fe}$.