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In this article, the electrical properties of 3C-SiC are described and its potential for metal-oxide semiconductor field-effect transistors (MOSFETs) is demonstrated. The density of traps, D IT , at the interface of 3C-SiC/SiO 2 capacitors is determined by the conductance method subsequent to various processing steps; the origin of the interface traps is discussed. Lateral and vertical 3C-SiC MOSFET devices of varying cell and device size are designed with hexagonal and squared cell geometry, and are fabricated side by side with MOS Hall bar structures. The electrical parameters of the MOSFETs are determined, and the free electron areal density and Hall mobility are measured in the channel of the MOS Hall bar structures. Based on the charge-sheet model, D IT is also obtained from the Hall investigations.

We report on the optical and electrical properties of cubic AlxGa1–xN/GaN heterostructures. The optical properties were investigated by photoluminescence measurements. A luminescence band at 3.250 eV was observed with our cubic AlxGa1–xN/GaN heterostructures. The emission lies between the excitonic emission of c-GaN at 3.276 eV and the donor-acceptor transition at about 3.135 eV. With increasing excitation power we find a characteristic blue shift of 4.5 meV/decade. To confirm the existence of a two-dimensional electron gas the transition energy versus externally applied voltage has been investigated. A 1.3 meV/V shift was measured and quantitatively verified by a self consistent solution of the Schrodinger and Poisson equation. The electrical properties were determined by capacity-voltage (CV)-measurements. The measured carrier profile is in excellent agreement with theoretical simulations and showed a sheet carrier concentration up to n = 1.6 × 1012 cm–2 at the AlxGa1–xN/GaN interface. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Total loss of agricultural fresh products amounts to 20% through 60% of the total amount of harvested products in any country, requiring an effective supply chain management model in agro-industry. This paper constructs a basic model of agricultural fresh products by formulating the plant growing process and the loss process of fresh products in mathematical forms. The model deals with periodical harvests through periodical flowering to satisfy demand. It is assumed that any on-hand inventory is not carried through more than one period and that any requirement for harvesting fresh products should be satisfied through the earliest plant maturing as possible. An optimal harvesting pattern is derived analytically to maximize the demand level satisfied.

Planar defects, like anti-phase boundaries (APBs) and stacking faults (SFs), are reduced by growing 3C-SiC on undulant-Si whose entire surface is covered with countered slopes oriented in the [110] and [[email protected][email protected]?0] directions. During the initial 3C-SiC growth, APBs are eliminated on each slope of an undulation. Then, one kind of SF self-vanishes. However, another kind of SF remains on the 3C-SiC surface, although its density is gradually reduced with increasing SiC thickness by combining with a counter-SF. The leakage current of a pn diode fabricated homo-epitaxially on 3C-SiC is roughly proportional to the SF density before homo-epitaxial growth. The viability of 3C-SiC grown on undulant-Si for semiconductor devices is discussed by reviewing recent reports on various MOS-FETs using it as the substrate. The key issue in the fabrication of a MOS-FET as a power-switching device operated at high-voltage is to reduce the leakage-current at the pn junction, thereby eliminating SFs.

PURPOSE The purpose of this study was to evaluate the use of radionuclide angiography and single photon emission computed tomography (SPECT) using Tc-99m hexakis-2-methoxyisobutylisonitrile (Tc-99m MIBI) for analyzing musculoskeletal lesions. MATERIALS AND METHODS Radionuclide angiography and SPECT using Tc-99m MIBI were performed in 36 patients with various soft tissue and bone pathologies (18 benign and 18 malignant lesions). The ratio of the counts of the lesion to that of the contralateral normal area was calculated from the region of interest drawn on the MIBI scan. The MIBI-uptake ratio was calculated using SPECT and the MIBI-perfusion index was calculated using radionuclide angiography. RESULTS The MIBI-uptake ratio in malignant lesions (4.80 +/- 4.43) was significantly higher (P < 0.05) than that in benign lesions (1.83+/-2.48). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-uptake ratio for malignant lesions were 72%, 83%, 78%, 81%, and 75%, respectively. The MIBI-perfusion index in malignant lesions (17.68 +/- 21.19) was significantly higher (P < 0.05) than that in benign lesions (2.25 +/- 2.56). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-perfusion index for malignant lesions were 87%, 75%, 81%, 77%, and 86%, respectively. CONCLUSIONS The MIBI-uptake ratio and MIBI-perfusion index using Tc-99m MIBI can yield important additional information with which to differentiate musculoskeletal lesions.

Lateral MOSFET devices with varying size from a single unit cell to 3x3 mm2 containing 1980 unit cells have been realised using two basic technologies; lateral trench MOSFET (LTMOS) with epitaxially grown source and drain, and lateral MOSFET with lightly doped drain (LDDMOS) having implanted source and drain regions. The LDDMOS devices had blocking capability of 100 V and the channel mobility in the range of 10 cm2/Vs in {-110} current flow direction and of 5 cm2/Vs in {110} current flow direction. The properties of both fabricated MOSFET types, LTMOS and LDDMOS, are dominated by a high density of interface states of the order of 1×1013 cm-2eV-1. Both the drain current and the leakage current scale linearly with the device size up to the maximum investigated device size of 3x3 mm2. No size limiting defects have been observed contrary to what is often the case in 4H-SiC material.

In this paper, we study the polytype transformation of cubic silicon carbide (3C-SiC) by micro Raman spectroscopy. Two sets of samples are investigated. First, physical vapor transport (PVT) grown samples, grown on chemical vapor deposition (CVD) substrates at growth temperatures between 1800 and 1950°C. The microscopic images of the cross sections and the Raman spectra taken on these grown crystals show a growing fraction of 6H-SiC inclusions with increasing growth temperature. To decide whether these polytype inclusions are induced by the PVT growth process or by the temperature treatment of the CVD substrates, we studied the temperature induced polytype coversion of cubic CVD substrates grown on undulant Si(100) surfaces which were used as seed crystals for the PVT growth. The CVD substrates were annealed in the temperature range between 1700 and 2100°C. The results of this annealing series are similar to the results we find in the PVT grown samples. Therefore we argue that the polytype conversion is not induced by the PVT growth process but a result of the heat treatment of the CVD seed crystals.

This paper considers minimizing the makespan in the “fixed, 3-machine, assembly-type flowshop scheduling (AFS)” problem. Since this problem has been proved strongly NP-complete, this paper proposes a series of heuristic algorithms based on the basic idea of Johnson’s algorithm, Gupta’s idea, the theorem newly provided in this paper, and worst/difficult case analyses. Numerical experiments show that the proposed heuristic algorithms can solve all of the worst cases which cannot be solved by the existing heuristic algorithms, and can solve all of the 90,000 instances generated randomly, meaning that the proposed algorithms are powerful enough to solve the fixed, 3-machine, AFS problem.

Objetivo: relatar o caso de um neonato masculino 47 XYY com doença cardíaca congênita e baixa estatura. Resultados: este é o primeiro relato de caso de um neonato masculino 47 XYY, pequeno para a idade, com doença cardíaca congênita (retorno venoso pulmonar anômalo total). O neonato nasceu com 32 semanas de gestação e peso de 1.134 g. Uma hemorragia intracraniana e um alto fluxo pulmonar foram descobertos no período neonatal inicial. Havia grande retardo de desenvolvimento neuromotor. A criança recebeu uma ligadura paliativa do ductus arteriosus e a colocação de um shunt ventriculoperitoneal, mas morreu com 19 meses de vida de insuficiência cardíaca. Comentários: esta combinação de menino XYY e doença cardíaca congênita pode ser fortuita. Entretanto, pensamos que é importante relatar que houve este caso de prognóstico pobre de um indivíduo XYY do sexo masculino com doença cardíaca congênita e baixa estatura.Objective: to report a case of a 47 XYY male neonate with congenital heart disease and short stature. Description: this is the first case report of a 47 XYY male neonate associated with congenital heart disease (total anomalous pulmonary venous return) and small for gestational age. The infant was born at around 32 weeks of gestation with 1,134g. Intracranial hemorrhage and pulmonary high flow were discovered in the early neonatal period. Retarded physical and mental development was observed. The infant underwent a palliative ligation of the ductus arteriosus and a ventriculoperitoneal shunt operation, but died due to consequent heart failure at 19 months of age. Comments: this combination of XYY male and congenital heart disease may be fortuitous. However, we think it is important to report that there was a poor prognosis case of XYY male with congenital heart disease and short stature.

A novel technique to eliminate planar defects in the 3C-SiC hetero-epitaxial layer on Si substrate was developed. Before growing 3C-SiC, countered slopes oriented in the [1 1 0] and [ 1 1 0] directions were formed over the entire surface of Si (0 0 1) substrate (undulant-Si). In the initial stage of 3C-SiC growth, step flow epitaxy occurred on the surface slopes of the substrate, reducing the anti-phase boundaries. Continuous, twin boundaries (TBs) were arranged in parallel along the (1 1 1) or ( 1 1 1) planes. The twin boundaries were eliminated through combination of the countered TBs with 3C-SiC growth. Finally, no planar defects were observed on the surface of 200-μm thick 3C-SiC grown on “Undulant-Si”.

Objectives: Combination therapy using an angiotensin II receptor blocker is expected to promote medication adherence and alleviate economic burden among patients by reducing the number of drugs taken, and thereby to lower associated medical costs. In the present retrospective study, we conducted a survey on the use of angiotensin II receptor blocker–containing combination tablets as anti-hypertensive drugs, in particular angiotensin II receptor blocker/diuretic and angiotensin II receptor blocker/calcium channel blocker combinations, in order to investigate the number of prescribed drugs and drug cost. Methods: We performed a retrospective study of patients who visited the outpatient clinic of GifuMunicipalHospital and received anti-hypertensive agents between June 2006 and December 2011. Results: No reductions in the number of prescribed drugs or drug cost were seen following a change in prescription to an angiotensin II receptor blocker/diuretic. Patients receiving an angiotensin II receptor blocker/calcium channel blocker had a significant reduction in the number of prescribed drugs and a slight decrease in drug cost. Conclusion: In this study, a reduction in the number of prescribed drugs and a decrease in economic burden were not observed after prescription of angiotensin II receptor blocker–containing combination tablets. In order to assess the usefulness of angiotensin II receptor blocker combination tablets, further studies are necessary to investigate their hypotensive effects, safety profile, and other factors.

The combination of angiotensin receptor blockers (ARB) and a thiazide diuretic (hereafter, ARB/diuretic) is expected to improve patient adherence and increase the therapeutic effects because of the lower number of pills that require to be administered. In addition, an ARB/diuretic combination alleviates hypokalemia that frequently develops in patients receiving thiazide diuretics. In this study, we used electronic medical records to investigate the laboratory values (serum levels of potassium, sodium, and uric acid) of 194 ambulatory and hospitalized patients at the Gifu Municipal Hospital who received ARB/diuretic combination therapy for the first time between February 2010 and September 2012. According to the grade of classification of low serum potassium and sodium levels, the serum potassium level in one patient was grade 3 and the serum sodium level in two patients was grade 3 after the initiation of ARB/diuretic combination therapy. After administration of ARB/diuretic combination therapy, two patients received potassium supplements because their serum potassium levels decreased below the reference value. Similarly, one patient received a sodium supplement because of a decrease in the sodium level below the reference value. Uric acid level increased above the reference value after administration of the ARB/diuretic combination therapy in one patient; thus, this patient received antihyperuricemic agents. Therefore, pharmacists must carefully monitor the serum levels of potassium, sodium, and uric acid, particularly in the first six months after the initiation of ARB/diuretic combination therapy.

Some investors pursuing a high return at the relatively high risk of losing a part of their money do not always select a preferred portfolio from among the so-called “mean-variance efficient frontier” provided by Markowitz (1959, Portfolio Selection, Wiley, New York). Chue and Nagasawa (1996, An investor-modeling and interactive method in multiobjective portfolio selection, Proceedings of the Pacific Conference on Manufacturing '96) constructed their own investor model based on an “α-risk permission maximum return portfolio” and proposed an interactive portfolio selection system for selecting a preferred portfolio from the set of candidate portfolios. This paper extends the system to the case when the mean and the variance of return of securities have several scenarios with known occurrence probabilities.

We have investigated metalorganic vapor phase epitaxy-grown GaN grains on a 3C-SiC(0 0 1) substrate using micro Raman and micro photoluminescence spectroscopy. Polarized micro Raman spectra clearly showed that horizontal flat facets and inclined facets of the rectangular GaN grains correspond to cubic phase regions and hexagonal phase regions, respectively. To examine the photoluminescence properties of “pure” cubic GaN, micro photoluminescence was performed by focusing a laser beam on the horizontal flat facet. A strong photoluminescence line with the full-width at half-maximum of 5 meV was observed, which is the smallest value to date and shows that the crystal quality of the cubic phase region is excellent. We could clearly identify free exciton, donor bound exciton and acceptor bound exciton emissions in the cubic GaN.

In this work, we focus on the fabrication of cubic GaN based Schottky-barrier devices (SBDs) and measured current voltage (I-V) characteristics and the critical field for electronic breakdown. Phase-pure cubic GaN and c-Al"xGa"1"-"xN/GaN structures were grown by plasma assisted molecular beam epitaxy (MBE) on 200@mm thick free-standing 3C-SiC (100) substrates, which were produced by HOYA Advanced Semiconductor Technologies Co., Ltd. The thickness of the c-GaN and c-Al"0"."3Ga"0"."7N epilayers were about 600 and 30nm, respectively. Ni/In Schottky contacts 300@mm in diameter were produced on c-GaN and c-Al"0"."3Ga"0"."7N/GaN structures by thermal evaporation using contact lithography. A clear rectifying behavior was measured in our SBDs and the I-V behavior was analyzed in detail, indicating the formation of a thin surface barrier at the Ni-GaN interface. Annealing of the Ni Schottky contacts in air at 200^oC reduces the leakage current by three orders of magnitude. The doping density dependence of breakdown voltages derived from the reverse breakdown voltage characteristics of c-GaN SBDs is investigated. The experimental values of breakdown voltage in c-GaN are in good agreement with theoretical values and show the same dependence on doping level as in hexagonal GaN. From our experimental data, we extrapolate a blocking voltage of 600V in c-GaN films with a doping level N"D=5x10^1^5cm^-^3.

Vertical power DMOSFETs in 3C-SiC, ranging in size from a single-cell to 3x3mm^2 containing 12,000 hexagonal cells, were developed for the first time. Both the drain and leakage currents scale linearly with device size up to a 1x1mm^2 device containing 976 cells. An inversion channel mobility of 40cm^2/V.s and interface state density of 5x10^1^2 to 1x10^1^3cm^-^2eV^-^1 were obtained. A fabricated DMOSFET with a gate length of 2@mm had a low specific on-resistance of 5.6m@W.cm^2 for a single-cell device. A current density of 1220A/cm^2 for a single-cell device, and 380A/cm^2 for a 102-cell device were demonstrated. A high current capability of 41 to 132A at 600V can be extrapolated for a 3x3mm^2 chip.

Several methods for evaluating left ventricular stroke volume (SV) in neonates using echocardiography have been reported. However, no studies on methodologic comparison of SV with three-dimensional (3D) echocardiography are available. This is the first detailed report on a methodologic comparison of SV in the early neonatal period. The study group included 70 normal neonates (35 boys and 35 girls). An iE33 echocardiograph and Q-LAB supplied by Philips Electronics were used to examine and calculate volumes. Comparisons of SV were performed using Teichholz (T), the velocity time integral (VTI), Pombo (P), modified Simpson (MS), and 3D methods with normal neonates who had no persistent ductus arteriosus less than 7 days after birth. The mean SVs were 33.7 mL/m(2) (T), 30.6 mL/m(2) (VTI), 22.0 mL/m(2) (P), 17.5 mL/m(2) (3D), and 14.9 mL/m(2) (MS) using Haycock's formula of body surface area. The stroke volumes differed significantly depending on the different methods. The correlation coefficient was highest between the MS and 3D methods. The SVs of the T and VTI methods were significantly greater than those previously reported, and it seemed inappropriate to evaluate volumes in neonates. The 3D and MS methods were appropriate for measuring SV in neonates during the early neonatal period.

The heteroepitaxial growth of 3C-SiC on Si(001) substrates has been studied in a hot-wall-type low-pressure reactor. The Si substrates were carbonized by C2H2 prior to the SiC growth process to suppress the undesirable effects of lattice mismatching between Si and 3C-SiC. A single-crystal carbonized layer (3C-SiC) was obtained from 500 °C to higher than 1000 °C in an C2H2 environment. Following the carbonization process, SiH2Cl2 and C2H2 were alternately supplied into the reaction tube to grow an epitaxial 3C-SiC film. The growth rate of 3C-SiC depended on the amount of Si incorporated into the surface of the substrates by H2 reduction of SiCl 2 as a Si precursor. The H 2 intermittent flow method employed during the SiC growth process efficiently suppressed the reduction of SiCl 2 and induced a constant growth rate of the SiC. The crystallinity of the grown 3C-SiC films on Si substrates was evaluated using transmission electron microscopy, selected-area electron diffraction, anti X-ray diffraction methods. The grown 3C-SiC films included anti-phase boundaries and twins. The concentration of these plane defects decreased due to coalescence with each other during SiC growth and resulted in an improvement in crystallinity and electrical properties.

We have deposited epitaxial diamond films with very low angular spread on epitaxial beta-phase silicon carbide layers on silicon (001) substrates. From x-ray rocking curve measurements, half-widths of the angular spread of the crystal orientation as low as 0.6 deg have been determined, which is the smallest value ever reported in heteroepitaxial diamond films and appears to be smaller than those of the beta-phase silicon carbide underlayers. The film surface exhibits a roughness of about 100 run with very few discernible boundaries due to misorientation. The optimization of the bias-enhanced nucleation process and the control of selective growth are the main factors for the improvement of the crystallinity.

We have attempted to grow heteroepitaxial 3C-SiC films on Si(001) substrates with high productivity by a hot-wall type low pressure chemical vapor deposition (LPCVD) using an alternate supply of acetylene (C 2 H 2 ) and dichlorosilane (SiH 2 Cl 2 ) into a reaction tube. In order to realize a high quality and large area single crystalline SiC formation, we have inquired into the desorption behavior of C 2 H 2 molecules in the SiC growth process. We suggested that a layer-by-layer SiC growth which was realized by a self-limiting adsorption of Si species (SiCl 2 molecules) was brought about by a decrease in adsorbed C 2 H 2 molecules on the surface. The growth of single crystalline 3C-SiC films on large area Si(001) substrates was realized by the self-limiting adsorption of SiCl 2 molecules at 1020°C. The thickness deviation of grown SiC film along the wafer diameter calculated as three times standard deviation divided by an average value was less than 1.5% over the 6 inch diameter.

A new sampling apparatus for the liquid-phase dissolution and graphite-furnace AAS technique has been developed in order to examine the distribution of trace metallic impurities on a silicon wafer. The apparatus is equipped with five indicater-rods and a wafer-moving stage for collecting metallic impurities at different areas on a wafer. Although the detection limit is raised with decreasing the sampling area, it reactes 108 to 109atoms cm-2 when a hydrofluoric acid solution of 20 μl is used for determing one metallic element in a sampling area of 1225 mm2.

Spondylocostal dysostosis (SCD) is a very rare syndrome characterized by vertebral malformation and rib deformity. Some of the patients with SCD have other birth defects in the central nervous system, the genitourinary tract, diaphragm or heart and so forth. There have been reported SCD with complex congenital heart disease, such as pulmonary atresia, double outlet right ventricle, and d-transposition of great arteries. However, there have been no reported SCD patients with confirmed tetralogy of Fallot (TOF). Here, a patient with SCD having a very rare combination of rib defects on the right side and left-sided scoliosis, tetralogy of Fallot, and diaphragmatic spleen herniation, which had not been reported before, was described.

Patient: Male, 5 Final Diagnosis: Osteoblastoma Symptoms: — Medication: — Clinical Procedure: — Specialty: Oncology Objective: Rare disease Background: Osteoblastomas are relatively uncommon bone tumors that account for

Polycrystalline and single-crystalline 3C silicon carbide films hetero-epitaxially grown on 3′' or 4′' Si wafers have been obtained by a hotwall type low-pressure chemical-vapour deposition (LPCVD). The internal stress of the polycrystalline film can be adjusted from 30 to 250 MPa (tensile) by changing the growth parameters, while that of the single crystal ranges from 100 to 200 MPa (tensile). The stress uniformity of the 46 mm2 polycrystalline membrane is measured to be ±9.7%, while that of the single one is ±3.0%. The biaxial Young's modulus is around 450 GPa for both the films and the burst strength for a 2.0 μm thick 20 mm2 polycrystalline membrane is about 0.4 kgf cm−2. Optical transparencies of 1.0 μm thick membranes are 70 and 80% at 633 nm for the polycrystal and the single crystal, respectively. The single crystal always shows higher transmission over the wavelength range studied and an extended absorption edge to the shorter wavelengths. The current values of mobility, carrier density and resistivity of the single crystal are roughly 180 cm2 V−1 s−1, 2 × 1018 cm−3 and 0.02 Ω cm, respectively.

Capacity design problems in a flexible manufacturing system (FMS) with a Poisson arrival process and with limited system-capacity are formulated to determine the number of boxes to store arrival jobs in a suppleinenta,ry wa,rehouse, called t8he "warehouse capacit,~," and the number of pallets available in the FMS. The throughput of the FMS is performed through a,n approximate closed queueing network model. The limits, and the first- a,nd the second-order properties of the throughput function with respect to the wa,rellouse ca,pa,cit,y a,nd t

Background Several coronary artery Z score models have been developed. However, a Z score model derived by the lambda-mu-sigma (LMS) method has not been established. Methods Echocardiographic measurements of the proximal right coronary artery, left main coronary artery, proximal left anterior descending coronary artery, and proximal left circumflex artery were prospectively collected in 3,851 healthy children ≤18 years of age and divided into developmental and validation data sets. In the developmental data set, smooth curves were fitted for each coronary artery using linear, logarithmic, square-root, and LMS methods for both sexes. The relative goodness of fit of these models was compared using the Bayesian information criterion. The best-fitting model was tested for reproducibility using the validation data set. The goodness of fit of the selected model was visually compared with that of the previously reported regression models using a Q-Q plot. Results Because the internal diameter of each coronary artery was not similar between sexes, sex-specific Z score models were developed. The LMS model with body surface area as the independent variable showed the best goodness of fit; therefore, the internal diameter of each coronary artery was transformed into a sex-specific Z score on the basis of body surface area using the LMS method. In the validation data set, a Q-Q plot of each model indicated that the distribution of Z scores in the LMS models was closer to the normal distribution compared with previously reported regression models. Finally, the final models for each coronary artery in both sexes were developed using the developmental and validation data sets. A Microsoft Excel–based Z score calculator was also created, which is freely available online (http://raise.umin.jp/zsp/calculator/). Conclusions Novel LMS models with which to estimate the sex-specific Z score of each internal coronary artery diameter were generated and validated using a large pediatric population.

Heteroepitaxial growth of 3C-SiC on Si(001) substrate has been realized by the use of a hot-wall type LPCVD with an alternating supply of acetylene (C 2 H 2 ) and dichlorosilane (SiH 2 Cl 2 ) in the temperature range 1000–1050°C. By synchronizing hydrogen (H 2 ) supply with C 2 H 2 supply, the reduction of SiCl 2 molecules on the surface of the substrate during SiH 2 Cl 2 supply was suppressed, resulting in the realization of the self-limiting process of SiCl 2 adsorption in the SiC growth process. The growth rate of 3C-SiC was independent of the temperature, the flow rate of the SiH 2 Cl 2 and the duration of the SiH 2 Cl 2 supply. To suppress the reduction of the SiCl 2 molecules during the SiH 2 Cl 2 supply seems to be a necessary condition to realize layer-by-layer growth of SiC. Since residual C 2 H 2 molecules hinder the SiCl 2 molecules from being adsorbed on the substrate, the C 2 H 2 molecules on the surface of the substrate may give rise to a suppression of SiC growth.

This paper discusses modelling of a multiobjective-head-headquarters, three-level decentralized system which consists of one headquarters, several divisions and factories. A mathematical model is formulated for this decentralized system. An optimal solution method based on the “revised two-level simplex algorithm with domination trees” is proposed for solving this type of three-level decentralized system.

“Complex Random Sample Scheduling(CRSS)” was proposed in this paper as an efficient heuristic method for solving any permutation scheduling problems. To show the effectiveness of the proposed CRSS, it was applied to an N -job, M -machine, permutation flowshop scheduling problem to minimize makespan, N / M / F / F max . Numerical experiments made it clear that the proposed CRSS provides a schedule very close to the near-optimal schedule obtained by the existing promising heuristic methods such as taboo search and simulated annealing, within less computation time than these heuristic methods.