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The plastic deformation of a thick-walled tube subjected to internal pressure is investigated by an incremental finite element method and the maximum bearing pressure is estimated. The results are compared with some approximate solutions proposed by MacGregor and others. A useful design formula is derived in order to estimate the maximum pressure and it is shown that better estimation can be made by this formula than by others proposed previously.

The present paper will discuss the efficient, practical and definitive algorithm for dealing with constrained load flow problems. Algorithms based on mathematical programming and algorithms based on the load flow calculation methods have been studied since earlier days. However, on account of numerous control variables to be determined and of inadequate calculating efficiency, the guarantee of unfailing solution is yet to be achieved. In the calculating procedure herein described the extents of adjustments are not determined simultaneously for all the control variables ; the control variables considered likely to produce greater adjusting effect are selected one by one and are adjusted successively. This adjustment method, as a consequence, is useful not only for on-line power system operation but also as simulator software for training system operators.

This paper presents an analysis of the results of the treatment of fracture dislocation of the ankle.The final clinical results were studied in 44 patients with 46 fractures at the ankle treated at the Yamaguchi Rosai Hospital between 1977 and 1982. The anatomical results of the reduction affected significantly the final clinical results.

A planning method is proposed for determining the optimal operational policy of a gas turbine combined heat and power plant connected with distributed heat supply plants at several districts. For the purpose of the efficient planning, a hierarchical approach is adopted. At the first level, the optimal operational policy is determined for each heat supply plant so as to minimize the required amount of input energy. At the second level, the optimal operational policy is determined for the combined heat and power plant so as to minimize its operational cost. These optimization problems are formulated respectively as a mixed-integer quadratic programming problem and a mixed-integer linear one, and they are both solved by applying the branch and bound method. Lastly, the effectiveness of the proposed method is ascertained through a case study.

The present paper describes a case study on economic evaluation of some alternative cogeneration plants to be installed into a local energy center in a district heating and cooling project. First, energy demands are estimated according to the construction plan of buildings. Then, a simple gas turbine cycle plant, a combined gas and steam turbine cycle plant, and a steam injected gas turbine cycle plant are selected as alternatives for investigation together with a conventional plant. Operational strategies are assessed so as to minimize the hourly running cost using an optimal operational planning method. Lastly, long-term economics for alternative plants are evaluated on the basis of the annualized costs method, and they are compared with one another. Through the study, it is ascertained that the annual total cost is minimized by introducing the conventional plant at the first stage with low energy demands, and by adding the cogeneration plant, in particular, of the steam injected gas turbine cycle type at the second stage with high energy demands.

The envelope equation derived earlier is generalized to analyze a resonance among multiple modes by using the method of multiple scales, an excellent method for analyzing large-scale nonlinear systems. It is demonstrated through numerical simulations that the generalized envelope equation is valid for predicting the resonance phenomena themselves and also for examining the critical factors responsible for severe resonances. The factors chosen for study are the heaviness of the load, small dampings, and disturbances. The method is promising for the analysis of general multimode resonances. >

With the objective of developing a computer-aided design method to seek the optimal semisubmersible’s form, hierarchical relationships among many design objectives and conditions are investigated first based on the interpretive structural modeling method. Then, an optimal design method is formulated as a nonlinear multiobjective optimization problem by adopting three mutually conflicting design objectives. A set of Pareto optimal solutions is derived numerically by adopting the generalized reduced gradient algorithm, and it is ascertained that the designer can determine the optimal form more rationally by investigating the trade-off relationships among design objectives.

Twenty-four children between one and thirteen years of age were treated for fracture of the femoral shaft during the years 1976 to 1982 at Yamaguchi Rosai Hospital.Fifteen cases of these were reviewed and checked roentogenologically with regard to difference in limb length and angular deformity. Conservative treatment or external skeletal fixation was done for all cases except two elderly cases.Correction of angular deformity and overgrowth of bone were measured and the results discussed.

Cranio-carpo-tarsal dysplasia is a rare syndrome first descrived by Freeman and Sheldon in 1938. Major features of this syndrome consist of a characteristic facial appearance causing the individual to appear as if whistling, ulnar deviations of fingers, scoliosis and talipes equinovarus. Our patient has this complex of congenital malformations.

A planning method is proposed for determining the optimal operational policy of a gas turbine combined heat and power plant connected with distributed heat supply plants at several districts. For the purpose of the efficient planning, a hierarchical approach is adopted. At the first level, the optimal operational policy is determined for each heat supply plant so as to minimize the required amount of input energy. At the second level, the optimal operational policy is determined for the combined heat and power plant so as to minimize its operational cost. These optimization problems are formulated respectively as a mixed-integer quadratic programming problem and a mixed-integer linear one, and they are both solved by applying the branch and bound method. Lastly, the effectiveness of the proposed method is ascertained through a case study.

Publisher Summary The cotransport of Na+ and electrically neutral organic substances is known to be electrogenic. A large Na+-dependent depolarization of cell membranes has been demonstrated to occur, in both renal proximal tubule and the small intestine, when D-glucose or L-neutral amino acid is added to the luminal fluid. This chapter discusses a method for quantitative determination of various resistance components of the proximal tubule and membrane resistance changes associated with cotransport are reinvestigated in newt kidney. Intraluminal current injection is adopted and the resultant voltage deflections are recorded from various points within the lumen and inside the cells along a nephron. The values of resistances are determined by simulation techniques with the aid of a digital computer. The chapter presents results that show that the luminal membrane resistance decreases considerably while the basal membrane resistance increases when L-alanine is introduced into the tubular lumen. The resistance of the paracellular shunt also changes to a small extent.

The clinicopathologic findings of 34 cases of cutaneous and subcutaneous leiomyomas were described. These were composed of 12 cases of piloleiomyoma and 22 of genital leiomyoma (scrotum, nipple and areola, vulva, and perianal region). Thirteen of 22 genital leiomyomas occurred in the vulva. Four cases of leiomyoma of pilar arrector origin had multiple lesions. The tumor occurred predominantly in adult females with an approximate sex ratio of 1:3 (8 males and 26 females). The patients with such leiomyomas ranged in age from 26 to 77 with an average of 46.8 years. The histologic feature in each case was essentially the same, and composed of interlacing bundles of smooth muscle cells, although vulvar leiomyomas frequently showed varying degrees of hyalinization and were composed of more slender tumor cells. All 12 cases submitted for immunohistochemistry showed a strongly positive staining both for actin and for desmin. In our view, cutaneous and subcutaneous leiomyomas, excluding angioleiomyomas, are undoubtedly rare in occurrence.

By comparing the published DNA sequences for (a) the genes encoding the human visual color pigments (red, green, and blue) with (b) the genes encoding human, bovine, and Drosophila rhodopsins, a phylogenetic tree for the mammalian pigment genes has been constructed. This evolutionary tree shows that the common ancestor of the visual color pigment genes diverged first from that of the rhodopsin genes; then the common ancestor of the red and green pigment genes and the ancestor of the blue pigment gene diverged; and finally the red and green pigment genes diverged from each other much more recently. Nucleotide substitutions in the rhodopsin genes are best explained by the neutral theory of molecular evolution. However, important functional adaptations seem to have occurred twice during the evolution of the color pigment genes in humans: first, to the common ancestor of the three color pigment genes after its divergence from the ancestor of the rhodopsin gene and, second, to the ancestor of the red pigment gene after its divergence from that of the green pigment gene.

We carried out a histologic, immunohistochemical and ultrastructural study of 19 tumors, previously classified as Ewing's sarcoma of the bone (ESB). The tumors were categorized histologically into four groups according to the presence or absence and the distribution of Homer-Wright rosettes, together with the immunohistochemical and ultrastructural features: 1) neuroectodermal tumor of bone (NTB) with diffusely dispersed rosettes (4 cases), 2) conventional ESB totally lacking the rosettes (9 cases), 3) intermediate-type tumor with characteristics of both NTB and ESB (4 cases), and 4) spindle cell-type tumor with focal rosettes (2 cases). Ultrastructurally, NTB contained neurotubules and neurosecretory granules, whereas ESB consisted of only undifferentiated cells. Immunoreactivity with antineural antibodies, such as Leu-7, and those against synaptophysin, NSE, neurofilament, and chromogranin, was detected in the majority of NTB, in intermediate- and spindle cell-type tumors and in two of the nine cases of ESB. In view of these findings, we propose that use of the term "neuroectodermal tumor of the bone" should be restricted to tumors with an extensive distribution of rosettes, and that those without unequivocal rosettes should be classified as ESB, although ESB may be the most undifferentiated form of NTB and some overlap may occur between the two tumor types.

This letter discusses a load frequency control scheme incorporating the computation delay time in the control law. When there is a computation delay in determining feedback gains, the incorporation of the time delay is necessary for the improvement of dynamic responses. The influences of the delay time on the responses are investigated using a two-area load frequency model.

The expander is a critical component of an organic Rankine cycle system as its performance in converting work from a high-pressure vapour greatly affects the overall efficiency of the system. Therefore, improving expander performance is one of the key elements in optimizing organic Rankine cycle systems. The use of oil-flooded expansion, i.e. adding significant amounts (by mass fraction) of lubricant oil to the working fluid before it enters the expander, is one of the concepts to achieve increased expander efficiency. In this work, an experimental organic Rankine cycle set-up has been built with an independent lubricant oil loop that allows testing the influence of oil flooding on a singlescrew expander. The heat source is simulated by an electric heater with a maximum capacity of 250 kWe and uses a thermal oil as the heat transfer fluid. The working fluid under consideration is the low- GWP refrigerant R1233zd(E) as a potential replacement for R245fa. Pressures, temperatures, mass flow rates and power measurements are logged. The data reduction and method used for altering the set-points is discussed. In addition, a preliminary experimental campaign has been conducted to investigate the possible influence of different oil flooding ratios at different pressure levels. The initial results show a decreasing trend in net specific power, cycle efficiency and isentropic efficiency for increasing flooding, and no observable effects on isothermal expansion are found. Additional research is required to eliminate the influence of certain testing conditions and to provide a more in-depth conclusion on the impact of liquid flooding on organic Rankine cycle performance.