Microprocessors in electric power systems

The present status of microprocessor applications in various fields of electric power systems is summarized. Special attention is directed towards development trends in the protection field where microprocessor applications are expected to cope with the increasingly stringent requirements for electric power supply reliability. Also discussed are the history, roles, design philosophy and basic schemes of microprocessor-based protective relaying systems. Only recently has their application reached a practical stage after long-term study and repeated field tests.     

Analytic Flow Design Method for an Automated Distribution Center with Multiple Shipping Areas

An analytic flow design algorithm for an automated distribution center with multiple shipping areas is presented. The main elements of the analytic flow design are the number of devices and the volumes of product flow between the devices. In the design of an automated distribution center, it is necessary to satisfy the demand throughput while minimizing construction costs. In the conventional design process, system engineers utilize experimental and intuitional approaches. However, conventional approaches are time-consuming and the design outcome is dependent on the skill of the designer. Therefore, a theoretical design algorithm is needed. We propose an analytic flow design algorithm using a dynamic network flow model and considering time-variable flow volumes according to shipment and storage schedules. To verify the feasibility of the proposed method, we perform analytic flow design using real data and confirm that the proposed method can yield a feasible analytic flow design in several minutes.     

Modelling and asset allocation for financial markets based on a stochastic volatility microstructure model

On the basis of the market microstructure theory, a continuous time microstructure model is proposed for describing the dynamics of financial markets with stochastic volatility property. From the microstructure model, one may obtain the estimates of two state variables, which represent the market excess demand and liquidity respectively but cannot be directly observed. Based on the indirectly obtained excess demand information instead of the prediction of price, a simple asset dynamic allocation approach is investigated. The local linearization method, nonlinear Kalman filter and maximum likelihood method-based estimation approach for the microstructure model proposed is presented. Case studies on the financial markets modelling and the estimated model-based asset dynamic allocation control for the JPY/USD (Japanese Yen/US Dollar) exchange rate and Japan TOPIX (Tokyo stock Price IndeX) show a satisfactory modelling precision and dynamic allocation performance.     

A Single Mutation at the Ferredoxin Binding Site of P450 Vdh Enables Efficient Biocatalytic Production of 25‐Hydroxyvitamin D3

Vitamin D₃ hydroxylase (Vdh) from Pseudonocardia autotrophica is a cytochrome P450 monooxygenase that catalyzes the two‐step hydroxylation of vitamin D₃ (VD₃) to produce 25‐hydroxyvitamin D₃ (25(OH)VD₃) and 1α,25‐dihydroxyvitamin D₃ (1α,25(OH)₂VD₃). These hydroxylated forms of VD₃ are useful as pharmaceuticals for the treatment of conditions associated with VD₃ deficiency and VD₃ metabolic disorder. Herein, we describe the creation of a highly active T107A mutant of Vdh by engineering the putative ferredoxin‐binding site. Crystallographic and kinetic analyses indicate that the T107A mutation results in conformational change from an open to a closed state, thereby increasing the binding affinity with ferredoxin. We also report the efficient biocatalytic synthesis of 25(OH)VD₃, a promising intermediate for the synthesis of various hydroxylated VD₃ derivatives, by using nisin‐treated Rhodococcus erythropolis cells containing Vdh_T107A. The gene‐expression cassette encoding Bacillus megaterium glucose dehydrogenase‐IV was inserted into the R. erythropolis chromosome and expressed to avoid exhaustion of NADH in a cytoplasm during bioconversion. As a result, approximately 573 μg mL^?1 25(OH)VD₃ was successfully produced by a 2 h bioconversion.     

Destruction of volatile organic compounds used in a semiconductorindustry by a capillary tube discharge reactor

Nonthermal plasma technologies offer an innovative approach to the problem of decomposing various volatile organic compounds (VOCs). The authors focused on DC capillary tube discharge plasma reactors to study the decomposition/destruction efficiency for toluene, EGM, trichloroethane and trichloroethylene at 50-2300 ppm levels in dry air. The effects of gas flow rate, VOC concentration and reactor operating conditions on decomposition and analysis of reactant conversion for each VOC were investigated. The results show that VOC destruction efficiency as high as 90% can be achieved, even under a short residence time (3.8 ms) with a destruction energy efficiency of up to 95 g (VOC)/kWh. Laboratory-scale plasma technology was successfully demonstrated for its potential application for VOC control in the semiconductor clean-room environment     

Scrotal ulcer occurring in patients with acute promyelocytic leukemia during treatment with all-trans retinoic acid

STUDY OBJECTIVE: To evaluate the efficacy of conservative laparoscopic surgery in a series of patients with stage III-IV endometriosis. DESIGN: Prospective study (Canadian Task Force classification II-1). SETTING: University-affiliated hospital. PATIENTS: All 141 women who underwent conservative operative laparoscopy for stage III-IV endometriosis between January 1993 and December 1996 and were followed for a minimum of 6 months. INTERVENTIONS: Laparoscopic procedures performed with scissors, bipolar coagulation, and hydrodissection. MEASUREMENTS AND MAIN RESULTS: Clinical examination, transvaginal ultrasonography, and pain questionnaire were scheduled every 6 months postoperatively. The cumulative proportion of pregnant patients and cumulative recurrence rate were calculated by Kaplan-Meier method. Twenty-five women (44%) with infertility became pregnant. Twenty-three (51%) had stage III and two (16.7%, p <0.05) had stage IV endometriosis. The 24-month cumulative pregnancy rate was 57.5%. Thirty-one women (22%) reported pain recurrence during follow-up. Five (3.5%) recurrences were confirmed by histologic examination and eight (5.7%) were documented only by clinical and ultrasonographic findings. No recurrence occurred in the first 6 months of follow-up. CONCLUSION: Operative laparoscopy seems to be effective treatment for stage III endometriosis. A larger series with longer follow-up is necessary to clarify its role in the management of stage IV disease. (J Am Assoc Gynecol Laparosc 6(1):55-58, 1999)     

VLSI implementation of a variable-length pipeline scheme fordata-driven processors

A VLSI-oriented variable-length pipeline structure for data-driven processors is presented. Ordinary inline pipelines have the problem of minimizing the average total processing time through the pipeline, since subdivision of a function along the pipeline is usually optimized for the most complex operations in spite of the fact that simpler operations need fewer stages. As a solution to this problem, a variable-length pipeline scheme in which data go through only the necessary stages according to information contained within is proposed. The scheme has been implemented on a test chip to verify performance. The chip demonstrated a minimum fall-through time (data transmission time from input to output) of 14.4 ns and a data transmission rate in the pipeline of 59 megaword/s (that is, 1/16.9 ns) as a first-in first-out (FIFO) store. By modifying the data transfer control and allocating the processing functions corresponding to the data interval of 16.9 ns, this scheme is applicable as a high-performance processing unit for data-driven processors     

Power system voltage control by distributed expert systems

A case study of the application of a distributed control scheme to a power system control is presented. In addition, an investigation has been conducted into voltage control. Combined injection of VAr-compensating devices controlled by distributed expert systems has been proposed as a measure to maintain voltage stability in a power system under heavy loading conditions. A simulation study has been carried out by using five workstations that represent a power system and four VAr-compensating devices. The results demonstrate the effectiveness of the proposed system for voltage recovery     

Gianotti-Crosti syndrome associated with cytomegalovirus antigenemia after bone marrow transplantation

Gianotti-Crosti syndrome (GCS) is characterized by a distinctive self-limiting acral papular or papulovesicular eruption associated with an underlying viral illness. It has not been previously reported in patients post-bone marrow transplantation. We report a 6-year-old Japanese boy who underwent allogeneic bone marrow transplantation from an unrelated donor for acute lymphoblastic leukemia (ALL) in second remission. He had clinical and histopathologic findings characteristic of GCS and evidence of subclinical infection with cytomegalovirus (CMV) detected by CMV antigenemia assay. It is likely that CMV is the causative agent for the GCS in this case.