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We reexamine the positive association between stock option vega and earnings management previously documented in Armstrong et al. (2013; ALOT). In contrast to ALOT, prior empirical research and practitioner literature emphasizes earnings management’s goals of increasing stock price and reducing volatility. Specifically, we assess whether the association is robust to (i) employing discretionary accruals that are less prone to misspecification, (ii) focusing on a more recent time period, and (iii) including additional controls for period-specific factors. Our main findings are as follows. First, we fail to find a positive association between vega and earnings management after controlling for performance-related misspecification in discretionary accruals. Second, we find no association between vega and earnings management in a more recent time period, suggesting the results of ALOT may be sensitive to period-specific factors. Lastly, the positive association vanishes when we control for year fixed effects, growth opportunities, or monitoring, suggesting the original ALOT’s results may be sensitive to correlated, omitted variables. Overall, our results question the extent to which vega incentivizes earnings management. Our results may be of interest to boards of directors in designing executive compensation contracts; to regulators in crafting policies that maintain high levels of financial reporting quality; and to researchers seeking to identify settings where earnings management incentives are most salient.

A molded case circuit breaker (MCCB) is one of the most important factors for safety to protect a load from overcurrent in a power distribution system. MCCB, which is mainly installed in switchboards and distribution boxes, may be affected by external temperatures and magnetic fields, but the above factors are still excluded from product standards and performance evaluation. This paper is the result of experimenting and studying the negative effects of these external temperatures and external magnetic fields on MCCB with short-circuit characteristic and dielectric recovery strength. As a result of temperature, it can be found that both short-circuit characteristic and dielectric recovery strength change linearly in accordance with the external temperature. The ratio of the values of 35 °C to 25 °C and 45 °C to 25 °C show the following results. t10, t21, and t32 are 1.58, 1.53, and 1.79, respectively, in short-circuit characteristics and ti, tm, and tl are 1.59, 1.69, and 1.53, respectively, in dielectric recovery strength. Depending on the external magnetic field, the short-circuit characteristics decreased by 8.56% only in the t21 period. The dielectric recovery strength decreases by 4.92% in the initial section (ti) and 14.45% in the later section (tl), respectively. It has been confirmed that the external magnetic field interferes with the emission of hot gas.

We reexamine the positive association between stock option vega and earnings management previously documented in Armstrong et al. (2013; ALOT). In contrast to ALOT, prior empirical research and practitioner literature emphasizes earnings management’s goals of increasing stock price and reducing volatility. Specifically, we assess whether the association is robust to (i) employing discretionary accruals that are less prone to misspecification, (ii) focusing on a more recent time period, and (iii) including additional controls for period-specific factors. Our main findings are as follows. First, we fail to find a positive association between vega and earnings management after controlling for performance-related misspecification in discretionary accruals. Second, we find no association between vega and earnings management in a more recent time period, suggesting the results of ALOT may be sensitive to period-specific factors. Lastly, the positive association vanishes when we control for year fixed effects, growth opportunities, or monitoring, suggesting the original ALOT’s results may be sensitive to correlated, omitted variables. Overall, our results question the extent to which vega incentivizes earnings management. Our results may be of interest to boards of directors in designing executive compensation contracts; to regulators in crafting policies that maintain high levels of financial reporting quality; and to researchers seeking to identify settings where earnings management incentives are most salient.

Far-infrared ray (FIR) therapy has been reported to exert beneficial effects on cardiovascular function by elevating endothelial nitric oxide synthesis (eNOS) activity and nitric oxide (NO) production. Tetrahydrobiopterin (BH4) is a key determinant of eNOS-dependent NO synthesis in vascular endothelial cells. However, whether BH4 synthesis is associated with the effects of FIR on eNOS/NO production has not yet been investigated. In this study, we investigated the effects of FIR on BH4-dependent eNOS/NO production and vascular function. We used FIR-emitting sericite boards as an experimental material and placed human umbilical vein endothelial cells (HUVECs) and Sprague–Dawley rats on the boards with or without FIR irradiation and then evaluated vascular relaxation by detecting NO generation, BH4 synthesis, and Akt/eNOS activation. Our results showed that FIR radiation significantly enhanced Akt/eNOS phosphorylation and NO production in human endothelial cells and aorta tissues. FIR can also induce BH4 storage by elevating levels of enzymes (e.g., guanosine triphosphate cyclohydrolase-1, 6-pyruvoyl tetrahydrobiopterin synthase, sepiapterin reductase, and dihydrofolate reductase), which ultimately results in NO production. These results indicate that FIR upregulated eNOS-dependent NO generation via BH4 synthesis and Akt phosphorylation, which contributes to the regulation of vascular function. This might develop potential clinical application of FIR to treat vascular diseases by augmenting the BH4/NO pathway.

This paper proposes an advanced simulation model of driving system for Interior Permanent Magnet (IPM) BrushLess Direct Current (BLDC) motors driven by 120-degree conduction method (two-phase conduction method, TPCM) that is widely used for sensorless control of BLDC motors. BLDC motors can be classified as SPM (Surface mounted Permanent Magnet) and IPM motors. Simulation model of driving system with SPM motors is simple due to the constant stator inductance regardless of the rotor position. Simulation models of SPM motor driving system have been proposed in many researches. On the other hand, simulation models for IPM driving system by graphic-based simulation tool such as Matlab/Simulink have not been proposed. Simulation study about driving system of IPMs with TPCM is complex because stator inductances of IPM vary with the rotor position, as permanent magnets are embedded in the rotor. To develop sensorless scheme or improve control performance, development of control algorithm through simulati...

This paper discusses the analysis and simulation method and the test method for a two-degree-of-freedom (2-DOF) actuator torque. The previous studies on the analysis of 2-DOF motor’s tilting torque were carried out only by finite element method (FEM), not by analytic method. This paper describes the operating principles of and the processes of inducing a tilting torque and a holding torque both of which exist only in special purpose electric machines. This allowed us to establish a design process. By overcoming the limits of the 3-D FEM, this paper introduced the 2-D model analysis by considering a real coil shape. Finally, this paper manufactured and tested the 2-DOF actuator to verify the introduced analytic analysis method.

We analyzed the results of tumours and tumour-like lesions arising in the foot and ankle and to establish the treatment guidelines. From 2006 to March 2013, 64 patients with 67 cases with primary tumours and tumour-like lesions arising in the foot and ankle were included. The benign lesions were 58 patients with 61 cases and the malignant tumours were 6 patients with 6 cases. Thirty patients were male and 34 patients were female. The mean age was 42.4 years old. The mean follow up period was 50.3 months. Fifty two lesions were located in the foot and 15 lesions were located in the ankle. Benign lesions were dominant, outnumbering malignant tumours by more than 10 to 1. The most predominant benign lesion was ganglion. Treatment options for benign lesions were excisional biopsy in 57 cases, curettage/grafting in 3 cases, and amputation in 1 case. Treatment outcomes were continuously disease free in 55 patients and local recurrence in 3 patients. Regarding malignant tumours, wide resection was in 1 case and amputation in 5 cases. Treatment outcomes were continuously disease free in 3 cases and died of disease in 3 cases. Thorough surgical excision is important for treatment of benign tumours and tumour-like lesions for preventing local recurrence. Limb salvage surgery is difficult for malignant tumours due to the peculiar anatomic complexity of these regions. Lager scale studies of the foot and ankle tumours and tumour-like lesions are needed to understand this rare subgroup of neoplasm.

Endometriosis is a chronic inflammatory condition that affects fertility and could be toxic to the ovary. Endometrioma per se and surgical interventions for endometrioma significantly reduce the ovarian reserve. Therefore, to prepare for surgical intervention for endometrioma, the high-risk group with decreased ovarian reserve must be considered. There is no evidence to support the use of surgical intervention before in vitro fertilization (IVF) to improve the reproductive outcomes of subsequent IVF in infertile women with advanced-stage endometriosis or endometrioma. As surgical treatment has few benefits, IVF could be recommended immediately for aiding conception in these women. However, the reproductive prognosis of IVF may be worse in the more advanced stages of endometriosis. When dysmenorrhea is severe or when cancer is suspected, surgery prior to IVF may be necessary and justified. When the size of the endometrioma is very large, surgery could be required prior to IVF to facilitate access to follicles during oocyte retrieval or to improve the ovarian response to controlled ovarian stimulation. Prolonged pituitary downregulation in women with surgically diagnosed endometriosis may be helpful to increase the clinical pregnancy rate in subsequent IVF cycles. The purpose of this paper was to review the efficiency and clinical application of the surgical intervention and IVF for infertile women with advanced-stage endometriosis or endometrioma.

The objective of our study was to determine whether adjuvant chemotherapy combined with postoperative radiotherapy would have benefits for the disease-free survival and overall survival in patients with high-risk endometrial cancer. Electronic searches for studies of adjuvant chemotherapy combined with postoperative radiotherapy in endometrial cancer patients between March 1971 and March 2012 were made on MEDLINE, SCOPUS, and the Cochrane library. Articles with more than 4 stars on the Newcastle-Ottawa scale or a score of more than 4 on the modified Jadad scale were included. A meta-analysis was performed, and pooled hazard ratios (HR) of progression-free survival (PFS) and overall survival (OS) between patients whose adjuvant chemotherapy was combined with radiotherapy (the CTx+RTx group) and patients with adjuvant radiotherapy only (the RTx group) were derived from the fixed effect model or random effect model. Three observational studies and 3 randomized clinical trials (RCTs) were included in the final analysis. Subgroup analysis for FIGO stage showed that the CTx+RTx group had a more significant survival benefit compared to that of the RTx group in advanced stage endometrial cancer (OS HR 0.53, 95% CI 0.36–0.80; PFS HR 0.54, 95% CI 0.37–0.77), but no significant benefit in early stage endometrial cancer (OS HR 0.96, 95% CI 0.70–1.32; PFS HR 1.00, 95% CI 0.39–2.58). This meta-analysis suggests that adjuvant chemotherapy combined with postoperative radiotherapy could probably reduce disease progression and overall death in patients with advanced-stage disease. In order to examine whether the multimodal treatment has benefit in high-risk endometrial cancer, we need further large-scale RCTs.

To realize the multi-Degree-of-Freedom (multi-DOF) movement, researches on spherical motor have been conducted in many countries. The Spherical motor has a 3-DOF, whose shaft can not only rotate as rotary motor but also tilt in the 2-DOF space. Researches on spherical motor will greatly contribute to 3-DOF systems, because spherical motor can reduce the size and weight of 3-DOF systems. This paper studies a new type of spherical motor that has rotating coils and tilting coils. Also, the current function depending on shaft angles is proposed. Finally, the torque is calculated corresponding to different shaft angles and rotating speeds. Moreover, these performances are validated via experiments.

As the need of electric motor is increased rapidly throughout our society, the various application fields are created and the service market called robot gets expanded as well as the existing industrial market. Out of those, the joint systems such as humanoid that is servo actuator for position control or all fields which require multi-degree of freedom (multi-DOF) require the development of innovative actuator. It is multi-DOF spherical motor that can replace the existing system in multi-DOF operating system. But, multi-DOF spherical motor that has been researched up to date is at the stage which is insufficient in performance or mechanical practicality yet. Thus, first of all the research results and limitation of the previously-researched guide frame-type spherical motors were analyzed and then the feature of double air-gap spherical motor which was devised to complement that was studied. The double air-gap multi-DOF spherical motor is very suitable spherical motor for system applying which requires the multi-DOF operation due to its simple structure that does not require other guide frame as well as performance improvement due to its special shape which has two air-gaps. So, the validity of the study was verified by designing and producing it with 3D-FEM through the exclusive jig for multi-DOF spherical motor.

In an electric motor in which permanent magnets are used, the magnetic flux is caused by the magneto-motive force of the permanent magnets of the rotor and the stator winding wire, and the performance of the electric motor is determined by the scale of the magnetic flux and the magnetic circuit. This thesis is aimed at introducing electric motors in which permanent magnets are used and focuses on a performance analysis of said electric motors according to the scale of the magnetic flux and changes in the magnetic circuit. The analysis was carried out by separating the magnetic flux occurring at the stator winding wire into the magnetic flux of axis d and that of q axis, so that the impact of the magnetic flux on the performance of the electric motor could be analyzed. In addition, the impact of changes in the magnetic circuit, which were caused by the magnetic flux at the permanent magnet of the rotator, on the electric motor was analyzed. Finally, the results of the analysis were verified by performing experiments on a model made by using selected analysis results.

Since robot industry growing, the machine that could move with multi-DOF has been studied in many industrial fields. Spherical motor is one of the multi-DOF machine that doesn't need gear for multi-DOF motion. Unlike conventional motor, spherical motor can not only rotate on the shaft axis (rotating motion), but tilt the shaft with 2-DOF motion (positioning motion). In the typical type of spherical motor, one coil took part in positioning motion and rotating motion at the same time. As the result, the control algorithm was complex. To solve this problem, this study proposed a novel type of coil on the stator. The coils were separated for positioning motion and rotating motion. Thus the linkage flux of rotating coil didn't be affected the positioning angle. In this paper, comparing the back-EMF of typical and novel type was conducted and the driving experiment was carried out as the positioning angle. From the experiment result, the performance of proposed spherical motor could be verified.

To construct a novel prognostic index (PI) model of early-stage epithelial ovarian cancer (EOC).The PI model was constructed through meta-analyses. The methodological quality of the studies was assessed using the modified Jadad scale for randomized controlled trials (RCTs) and the Newcastle-Ottawa scale for non-RCTs. The prognosis factors of the PI model that had a significant impact on the recurrence-free survival (RFS) of patients with early-stage ovarian cancer were chosen. A total of 177 patients with early-stage ovarian cancer who were treated at Severance Hospital were analyzed using the new PI model to test its utility.The equation PI=2 × age+86 (if grade 2) or 105 (if grade 3)+53 (if stage Ib or Ic) or 130 (if stage II)+53 (if no lymphadenectomy)-43 (for adjuvant chemotherapy of 3 times or more)+10 (calibrating constant) was derived. Based on PI values, the high-risk group showed a significant 5 year-RFS difference compared to the low-risk group (P-value0.01 by log-rank test) and a borderline significance in comparison to the intermediate-risk group (P-value=0.08). When the cutoff level of PI values was set at 211, the low- and high-risk groups of recurrence within 5 years were also identified by Cox regression analysis (HR=7.25, 95% CI: 2.98-17.65).Our PI model was predictive in this study and may be effective in clinical practice. Further prospective studies should be conducted to confirm the predictive ability of the new PI model for early-stage EOC recurrence.

Freestanding GaN was grown on sapphire substrate in a horizontal HVPE system, followed by laser lift-off process. The thickness of the freestanding GaN samples was about 350 μm. Si was used as an n-type dopant and the carrier concentrations were non-destructively measured by micro-Raman spectroscopy. The carrier concentrations of GaN samples were changed from 0.62 to 3.7×10 18 /cm 3 by varying the Si/Ga ratios from 0.01 to 0.04. Crystalline quality of the freestanding GaN was characterized by X-ray diffraction (XRD). The full-width at half-maximum (FWHM) values of the rocking curves of the (102) plane was changed from 96.9 to 317.5 arcsec depending on Si/Ga ratios. This work provides Si/Ga ratios to obtain various carrier concentrations of the freestanding GaN by HVPE, and proposes micro-Raman spectroscopy as a sensitive technique for carrier concentration measurement.

Objective The purpose of this prospective study was to evaluate the efficacy and safety of screw fixation without bone fusion for unstable thoracolumbar and lumbar burst fracture. Methods Nine patients younger than 40 years underwent screw fixation without bone fusion, following postural reduction using a soft roll at the involved vertebra, in cases of burst fracture. Their motor power was intact in spite of severe canal compromise. The surgical procedure included postural reduction for 3 days and screw fixations at one level above, one level below and at the fractured level itself. The patients underwent removal of implants 12 months after the initial operation, due to possibility of implant failure. Imaging and clinical findings, including canal encroachment, vertebral height, clinical outcome, and complications were analyzed. Results Prior to surgery, the mean pain score (visual analogue scale) was 8.2, which decreased to 2.2 at 12 months after screw fixation. None of the patients complained of worsening of pain during 6 months after implant removal. All patients were graded as having excellent or good outcomes at 6 months after implant removal. The proportion of canal compromise at the fractured level improved from 55% to 35% at 12 months after surgery. The mean preoperative vertebral height loss was 45.3%, which improved to 20.6% at 6 months after implant removal. There were no neurological deficits related to neural injury. The improved vertebral height and canal compromise were maintained at 6 months after implant removal. Conclusion Short segment pedicle screw fixation, including fractured level itself, without bone fusion following postural reduction can be an effective and safe operative technique in the management of selected young patients suffering from unstable burst fracture.

A surfaced permanent magnet spherical motor is capable of operating as three degree of freedom that used for the joints of the robot's arm, leg, and eyes. Ongoing research like new concept is essential part of motor field, it will make a great contribution in the future the overall portion of the motor, is becoming expected. The author analysis torque characteristics in spherical motor with state of rotating and positioning. And future design direction is smaller motors with equivalent or higher output. Solutions as torque and efficiency improvements are selecting the core with special processing type like powder metallurgy materials. Their special characteristic is high permeability and low eddy current losses at high speed, so improved the torque and efficiency.Key Words : Multi-D.O.F., Spherical motor, Soft magnetic composite, Torque characteristic, Permanent magnet motor*정 회 원 : 한양대 공대 전기공학과 박사과정** 정 회 원 : 동국대 공대 전자전기공학부 교수***정 회 원 : 한양대 공대 전기공학과 석박사 통합과정§ 정 회 원 : (주)삼성전자 선임연구원§§ 정 회 원 : 동양미래대 공대 전기시스템과 전임강사† 교신저자, 시니어회원 : 한양대 전기공학과 교수E-mail : julee@hanyang.ac.kr접수일자 : 2011년 9월 18일 최종완료 : 2011년 12월 9일

The closed intramedullary nailing is the treatment of choice for femoral diaphyseal fractures. These procedures typically have been performed on a fracture table with either supine or lateral position. However, the use of a fracture table has a lot of disadvantages compared to a lateral position on radiolucent routine table. We reviewed one hundred and twenty-eight patients with femur fractures between 2005 and 2009, who were treated with closed femoral intramedullary nailing in lateral decubitus position on radiolucent routine table. Indirect reduction was facilitated by the aid of intraoperative skeletal traction. Clinical and radiologic results were evaluated. There were no rotational or length malreductions that required surgical revision. There were no injuries to the perineum or contralateral leg, nerve palsies, or fracture table–related complications. There were three cases of non-union and two cases of interlocking screw loosening. Lateral decubitus position obviates the need for fracture table, making it easier to establish an entry point for an intramedullary device. Closed femoral intramedullary nailing in lateral decubitus position with the aid of intraoperative skeletal traction is safe and an effective technique with a low incidence of complications compared to the use of fracture table.

Enchondroma is the most common benign tumor that frequently occurs in hand. Curettage followed by augmentation of the void defect is the mainstay of enchondroma treatment such as autologous bone grafting or using bone graft substitutes. In this study, we analyzed the surgical results of a hand enchondroma treated by curettage and grafting with calcium sulfate pellet (OsteoSet®, Wright Medical Co, USA) grafting. Eighteen patients with hand enchondroma were reviewed. There were seven male cases and eleven female cases with the mean age of 35.4 years (range, 12–55). Involved bones were metacarpal (5 cases), proximal phalanx (7 cases), middle phalanx (3 cases) and distal phalanx (3 cases). The mean follow-up period was 32 months (range, 18–48). We analyzed the clinical result and radiologic appearance of the surgically treated digits. The resorption of calcium sulfate pellet and bone remodeling were checked by serial radiographs. The mean time for complete pellet resorption was postoperative 4 weeks (range, 3–6 weeks). Bone remodeling was completed in all cases at mean postoperative 10 weeks (range, 7–11). All surgically treated digits had full range of motion except one digit that was fixed with K-wire to treat a pathologic fracture simultaneously. No other complications and local recurrence were encountered. Curettage and calcium sulfate pellet (OsteoSet®) grafting proved to be a safe, promising modality for treatment for hand enchondroma. It led to excellent functional and radiologic results.

Torque ripple of the motor used in EPS raises vibration problem on steering system. To solve this problem, this paper proposes a optimum design for torque ripple reduction of Surface-mounted Permanent Magnet Synchronous Motor(SPMSM) in EPS. Through analyis back-EMF using Finite element method as changing the shape of permanent magnet and stator shoe, we presented the method of torque ripple redution.

Antepartum pituitary necrosis is a rare medical condition that has only been reported in pregnant women with type I diabetes attributable to diabetes-related vasculopathy and hypercoagulability. We present for the first time a case of antepartum pituitary necrosis occurring in an uncontrolled gestational diabetes mellitus (GDM) patient. The patient was a 32-yr-old woman at 33 weeks and 2 days of gestation. She suffered from severe headache, blurred vision, dizziness, and vomiting. Her baby was delivered by Cesarean section. The brain magnetic resonance images revealed pituitary necrosis. This suggests that pituitary gland necrosis may also complicate GDM pregnancy when glucose levels are uncontrolled.

InN 1D materials were successfully grown by metal-organic vapor phase epitaxy (MOVPE) and non-catalytic, template-free hydride metal-organic vapor phase epitaxy (H-MOVPE) on Si, GaN, and c-Al2O3 substrates. Dislocation-free, high-quality InN nanorods with [00.1] growth axis were formed via an apparent vapor-solid (VS) growth mechanism by H-MOVPE. On a contrary when conventional MOVPE was employed InN nanowires were grown via vapor-liquid-solid (VLS) mechanism. The controlled growth of self-seeded III-Nitride nanostructured materials has been demonstrated.

Transmission Electron microscopy was applied to determine similarities and difference in structural perfection between InN epi-layers grown by MBE on c- and r-plane Al2O3 and InN nanocrystals grown on similar substrates using non catalytic, template-free hydride metal-organic vapor phase epitaxy. The study showed that nanocrystals had more perfect crystallinity compared to the layers. While the InN layer growth direction followed the crystallographically required epitaxial growth orientation, the nanorod growth was randomly oriented. The opposite growth polarity has been determined for the InN layers grown along c-direction (In-polarity) in comparison to nanocrystals grown along same direction (N-polarity). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

InN films and nanorods were grown by hydride metalorganic vapor phase epitaxy (H-MOVPE) and the effects of growth temperature, and NH 3 /TMIn and HCl/TMIn ratios on morphological dependences were studied. The growth habit of InN varied from thin film to microrod to nanorod to no deposition as the growth conditions were changed about transition from growth to etching conditions. The growth and etch regimes were also predicted by chemical equilibrium calculations of In–C–H–Cl–N-inert system. The optical properties of InN nanorods and columnar structured films were measured by room temperature PL and a maximum intensity was observed at 1.08 eV for both structures.

During the last years, several groups across the world have concentrated on the adaptation and further development of electrospinning (e-spinning) to enable ceramic fiber synthesis. Thus far, more than 20 ceramic systems have been synthesized as micro- and nanofibers. These fibers can be amorphous, polycrystalline, dense, porous, or hollow. This article reviews the experimental and theoretical basis of ceramic e-spinning. Furthermore, it introduces an expanded electro hydrodynamic (EHD) theory that allows the prediction of fired fiber diameter for lanthanum cuprate fibers. It is hypothesized that this expanded EHD theory is applicable to most ceramic e-spinning systems. Furthermore, electroceramic nanofibers produced via e-spinning are presented in detail along with an overview of electrospun ceramic fibers.

The impact of interdiffusion on strain energy in the GaN-sapphire system was studied. Gallium nitride epitaxial layers were grown on (0001) Al2O3 by low-pressure MOCVD at 850 °C, V/III ratio = 3600, P= 100 Torr using TEGa and NH3 sources in a N2 carrier. The ∼0.3 µm thick films were then annealed at growth temperature in N2 for a period of 30 to 120 min. The Al and Ga diffusion coefficients at 850 °C were estimated as DAl = 3.98 × 10–17 cm2/s and DGa = 4.81 × 10–17 cm2/s from SIMS depth profile data. A model was developed to predict the strain energy and describe its relaxation behavior. The calculations assume a gradual transition of lattice parameter near the interface rather than an abrupt transition. The effect of interdiffusion on the strain energy and predicted critical thickness were clearly demonstrated. The estimated strain energy of the first layer was only 176 J/mole, compared to 30 kJ/mole assuming an abrupt interface. For an anneal time of 120 min at 850 °C the model predicts that dislocations are formed when the strain energy reaches 10 kJ/mole after the 4th layer is added, compared to their formation after the 1st layer is formed when an abrupt interface is assumed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This study reports a non-destructive method of measuring the residual strain in the GaN epilayer grown on sapphire substrate by micro-Raman spectroscopy. Operating in confocal mode this method allows a depth-dependent measurement of residual strain in the epitaxial layer without prior treatment of the sample. This approach to measurement of residual strain is demonstrated on GaN epitaxial films grown by both MOCVD and H-MOVPE. In the case of MOCVD grown films, the biaxial strain energy was found to vary from 0 (GaN surface) to 5.0 kJ/mole (GaN/sapphire interface), but in the case of H-MOVPE grown samples the strain energy varied from 6.5 kJ/mole – hydrostatic strain (GaN surface) to 25.0 kJ/mole – biaxial strain (GaN/sapphire interface), indicating that the surface layer of the N-terminated H-MOVPE material is not free from strain. Estimates are given for the curvature of substrate, lattice parameter of epitaxial layer, and the interface shear modulus. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The rheological behavior of multiwall carbon nanotubes (MWCNTs) with polyelectrolyte dispersants (poly(acrylic acid) and poly(aspartic acid)) was investigated. The zeta potential of MWCNT slurries with adding dispersants and the optimum amount of dispersants for MWCNT slurries were measured. The Krieger–Dougherty equation was fitted to experimental data with varying solid loadings. The fitted results of MWCNT slurries showed the high intrinsic viscosity and the low maximum solid loading because of the high aspect ratio and the strong van der Waals force of MWCNTs. Poly(acrylic acid) stabilized MWCNT slurries had a lower maximum solid loading and a higher intrinsic viscosity ( ϕ m = 0.16, [ η ] = 43) compared to poly(aspartic acid) stabilized MWCNT slurries ( ϕ m = 0.21, [ η ] = 41.47). These differences may be caused by the different chemical structures of dispersants.

Poly(acrylic acid) (PAA) nanofibers were fabricated by electrospinning into NaCl solution. The effect of the ionic strength of NaCl on the morphology of PAA nanofibers was investigated. The smallest diameter of the PAA nanofiber was prepared with 0.01 M NaCl PAA solutions. At the concentration 1 M NaCl, PAA nanofibers could not be fabricated. The viscosity and conductivity changes were measured with changing the concentration of NaCl. It is suggested that diameter variations may be caused by conductivity and polymer chain conformation changes with varying the concentration of NaCl.

This study presents an analysis of healthcare quality indicators using data mining for developing quality improvement strategies. Specifically, important factors influencing the inpatient mortality were identified using a decision tree method for data mining based on 8405 patients who were discharged from the study hospital during the period of December 1, 2000 and January 31, 2001. Important factors for the inpatient mortality were length of stay, disease classes, discharge departments, and age groups. The optimum range of target group in inpatient healthcare quality indicators were identified from the gains chart. In addition, a decision support system (DSS) was developed to analyze and monitor trends of quality indicators using Visual Basic 6.0. Guidelines and tutorial for quality improvement activities were also included in the system. In the future, other quality indicators should be analyzed to effectively support a hospital-wide continuous quality improvement (CQI) activity and the DSS should be well integrated with the hospital order communication system (OCS) to support concurrent review.

This paper proposes a means to reduce torque ripple in a 2 poles, 30 (W) small size BLDC motor in radial blower. The BLDC motor have six times torque ripple interval per one period. This problem is the cause of noise and vibration that leads to the degradation of the output torque. For example, First, cogging torque is generated due to the reluctance difference of the teeth of the stator core for rotate time. It is the cause of noise and vibration that leads to the degradation of the performance. So, a plastic molding was used in order to reduce the cogging torque. The molding made the constant magnetic path between the stator and the permanent magnet thereby, reducing the cogging torque. Second, the torque ripple is generated due to a harmonic components of the magnetomotive force at the air gap difference. So a skewed permanent magnet was used in order to reduce the torque ripple. The validity of the thesis was proven via 2D, 3D FEA.

We sought to perform a quantitative analysis on operative outcomes of laparoscopic staging surgery in patients with presumed early-stage ovarian cancer using a metaanalysis.Electronic searches for studies of laparoscopic staging surgery in patients with ovarian cancer were performed within 3 electronic databases (Medline, Embase, and the Cochrane Library) using the key words "ovarian cancer," "early stage," "laparoscopy," "staging surgery," "staging laparoscopy," and "recurrence." Two authors independently screened articles, and those meeting the defined inclusion/exclusion criteria were included in the metaanalysis.We identified 11 observational studies. The combined results of 3 retrospective studies showed that the estimated blood loss in laparoscopy was significantly lower than that for laparotomy (P .001). The overall upstaging rate after laparoscopic surgery was 22.6% (95% confidence interval [CI], 18.1-27.9%) without significant heterogeneity among all study results. The overall incidence of conversion from laparoscopy to laparotomy was 3.7% (95% CI, 2.0-6.9%). The overall rate of recurrence in studies with a median follow-up period of ≥19 months was 9.9% (95% CI, 6.7-14.4%).Through our quantitative analysis, we concluded that the operative outcomes of a laparoscopic approach in patients with early-stage ovarian cancer could be compatible with those of laparotomy. In the future, further randomized controlled trials may be needed.

Chronic endometritis (CE) is a condition involving the breakdown of the peaceful co-existence between microorganisms and the host immune system in the endometrium. A majority of CE cases produce no noticeable signs or mild symptoms, and the prevalence rate of CE has been found to be approximately 10%. Gynecologists and pathologists often do not focus much clinical attention on CE due to the time-consuming microscopic examinations necessary to diagnose CE, its mild clinical manifestations, and the benign nature of the disease. However, the relationship between CE and infertility-related conditions such as repeated implantation failure and recurrent miscarriage has recently emerged as an area of inquiry. In this study, we reviewed the literature on the pathophysiology of CE and how it may be associated with infertility, as well as the literature regarding the diagnosis and treatment of CE. In addition, we discuss the value of hysteroscopic procedures in the diagnosis and treatment of CE.

This paper presents the analysis of shape of claw-pole in a PM stepping motor. The analysis of claw-pole PM stepping motor must consider magnetic saturation effect and leakage flux, because analyzed results can change with the magnetic characteristics of iron material. Generally, 3-Dimensional FEM was used in this case[1]. But 3-Dimensional FEM needs too much computation time. So, in this paper, modified magnetic equivalent circuit method to consider the magnetic saturation and the leakage flux was proposed. This proposed method points out the B-H curve of iron material approximated by fitting function and the flux linkage calculation by iteration routine. To verify the proposed method, flux linkage calculated by this method was compared with the result of 3-Dimensional FEM.

3-DOF spherical PM motor has 3 degrees of freedom in its motion by tilting and rotating the shaft, which is applicable in various fields. In this paper, D-Q-P vector control method is proposed for motion and speed control of the shaft. Using the reference table of current is the conventional control method obtained through numerous simulation and experiments. Vector control of general rotary motor has been researched for a long time. The vector control is the main control method in rotary motor because it allows an instantaneous torque control. But in the case of 3-DOF spherical PM motor, locus of magnet rotation varies by shaft position. So general D-Q axes vector control methods can't be applied directly. This paper shows D-Q-P vector control method for 3-DOF 4 poles spherical PM motor considering shaft response factor with mathematical and experimental verification.

Purpose: To analyze the effectiveness of anterior pelvic plating and subsequent percutaneous sacroiliac joint screw fixation in patients with unstable pelvic ring in juries. Materials and Methods: Thirty-two patients were included with twentyone males and eleven females. The mean age was 41 years (range, 19-76). The mean follow-up period was 51 months (range, 36-73). According to AO-OTA classification, there were 11 cases of B2 injuries, 8 cases of B3 injuries, 9 cases of C1 injuries, 2 cases of C2 injuries and 2 cases of C3 injuries. In the posterior lesions, there were 20 cases of sacral fractures and 12 cases of sacroiliac joint disruptions or dislocations. Anterior pelvic plating and subsequent percutaneous sacroiliac joint fixation were performed . Results: The clinical results were 16 cases of excellent, 10 cases of good, 4 cases of moderate and 2 cases of poor functional results. The 2 cases out of 7 moderate reductions had poor functional results with residual neurologic symptoms. The radiological results were 16 cases of anatomic, 9 cases of nearly anatomic and 7 cases of moderate reduction. All patients were healed except 3 cases of nonunion at the pubic ramus. The complications encountered were 3 cases of screw loosening, 2 cases of anterior plate breakage and 1 case of postoperative infection. Conclusion: In patients with unstable pelvic ring injuries, anterior pelvic plating and subsequent percutaneous sacroiliac joint screw fixation may be a useful surgical option. The radiological results and residual neu rologic symptoms had effects on its functional results.

OBJECTIVE Small cell carcinoma of the uterine cervix (SMCC) is extremely rare, and an aggressive disease that proliferates rapidly. It was often reported that the diagnostic accuracy of cytologic smears in diagnosing SMCC was low. This is a report of the Severance Hospital experience with the patients suffering from SMCC. METHODS Twenty-seven patients with small cell carcinoma of the uterine cervix were diagnosed and treated at the Severance Hospital from November 1991 to January 2010. The data were analyzed retrospectively, based on the available charts and pathology reports. Various fields, such as chief complaints and symptoms present at first clinic visit, age, International Federation of Obstetrics and Gynecology (FIGO) clinical stage, treatment modality, the 5-year overall survival rate, and recurrence rate were investigated. RESULTS Among the 27 patients diagnosed with small cell carcinoma of the uterine cervix, 18 of them (66.7%) presented with symptoms, including vaginal bleeding, at the first clinic visit, and the remaining 9 patients (33.3%) showed abnormal Pap smear screening in the process of their routine health check-up. The median age of the patients was 54 years (range, 24 to 77 years). FIGO stage IIB was the most common stage (11 of 27 patients). The 5-year overall survival rate of 21 patients, who could be followed up, was 57.2%. Six patients showed recurrence after remission, and the mean disease free interval of them was 9.2 months (range, 6 to 11 months). Abnormal Pap smear screening results of 9 patients was investigated, and the diagnostic accuracy of the cytologic findings was 22.2%. CONCLUSION Our study was consistent with the concept that Pap smear screening might not be helpful in early diagnosis of SMCC considering its low diagnostic accuracy. Further large-scale multicenter prospective studies are definitely needed in order to produce abundant information about optimal therapy and diagnosis.

Continuous silver-clad Y-123 wire has been fabricated from cofired green fibers produced by melt-spinning polymers loaded with Y-123 powders. Metal claddings are provided by coating with silver-alloy powder slurries. The sintered polycrystalline Y-123 wires have 77 K self-field critical current density (Jc) values up to 2900 A/cm2, with typical ranges in long lengths of about 1000 A/cm2, but are weak linked. High-Jc wire is made by continuous melt texturing of the presintered wires. Values of Jc above 10 000 A/cm2 at 77 K have been achieved.

Continuous silver-clad Y-123 wire has been fabricated from cofired green fibers produced by melt-spinning polymers loaded with Y-123 powders. Metal claddings are provided by coating with silver-alloy powder slurries. The sintered polycrystalline Y-123 wires have 77 K self-field critical current density (Jc) values up to 2900 A/cm2, with typical ranges in long lengths of about 1000 A/cm2, but are weak linked. High-Jc wire is made by continuous melt texturing of the presintered wires. Values of Jc above 10 000 A/cm2 at 77 K have been achieved.