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The relaminarization process of a turbulent boundary layer under a sink flow was investigated experimentally. The boundary layer was accelerated because of the contraction of the flow area. The mean and fluctuating velocity components were measured using a hot-wire anemometer. With relaminarization, the fluctuating velocity, which was normalized by the free-stream velocity, decreased. The degree of decrease differed between the streamwise and wall-normal components, depending on the distance from the wall. The conditional probabilities that two hot-wire probes separated in the spanwise direction simultaneously observed turbulent and nonturbulent flows were obtained. A spanwise-wide turbulent region was spread near the wall, but its width decreased as the distance from the wall increased. When the layer was relaminarized, this decrease in the spanwise width started near the wall. The low-speed streak spacing of the coherent structure was obtained from the lateral correlation coefficient of the streamwise fluctuating velocity and average spanwise spectra, and both parameters were somewhat consistent. Both the spanwise spacing of the streaks and the vertical scale of the coherent structure increased because of relaminarization. The conditional lateral correlation coefficient of the streamwise fluctuating velocity based on turbulence or nonturbulence was calculated. The streak spacing was slightly wider under nonturbulent conditions. This trend is consistent with the spreading behavior of the streak spacing, owing to relaminarization. With relaminarization, coherent structures became less frequent.

In this paper, the laminar-turbulent transition process of a mixing layer downstream of a two-dimensional nozzle exit was analyzed based on various information and complexity measures. Shannon entropy, permutation entropy, and approximated Kolmogorov complexity were also obtained. To obtain the Shannon entropy, the temporal probability distribution of the hot-wire output voltage data was determined and analyzed. In addition to the fluctuating velocity, its time derivative and the square of this derivative were analyzed. The Shannon entropy of the time derivative and its square slightly decreased downstream, in accordance with the increase in the time scale of the turbulence. When the length of the extracted data was constant, the permutation entropy of the time derivative and its square increased around the peripheral region of the mixing layer, in accordance with the intermittent nature of the velocity signals. The region is at the 3-4 times farther from the jet centerline than the region where the fluctuating velocity becomes maximum. When the length of the extracted data was varied in accordance with the integral time scale of turbulence, the permutation entropy initially decreased in the potential core and subsequently increased after the disappearance of the potential core, as the transition progressed. The approximated Kolmogorov complexity of the time derivative and its square were smaller than that of the fluctuating velocity. Owing to the simplification of the data, they slowly increased after the disappearance of the potential core and then quickly decreased after the development of turbulence.

This paper describes how to produce a biodiesel fuel (BDF) from the waste soup of ramen noodles, especially focusing on the recovery process of the oil (triglycerides) from a large amount of waste soup or the oily wastewater disposed of by pouring it down the sink by a ramen restaurant. By combining a semi-transparent bucket (~6 L) with a cock and solvent extraction, it is shown that oil can be recovered easily from 300 or more bowls of ramen noodle waste soup, with an energy profit ratio (EPR) of more than 5.2. The initial cost of the bucket is about 1600 yen, so it has little effect on the price of the BDF produced from the oil in the ramen noodle waste soup, and it is shown that the increase in running cost to produce BDF by this method is about 2.3 yen/L if the rate of recovery of hexane (solvent) is over 99%, which is approximately equivalent to the production cost of waste-cooking-oil BDF production by previously reported methods. Furthermore, in the case of applying the proposed method based on the solvent extraction to the recovery of oil from the oily wastewater disposed of by a ramen noodle restaurant, it is shown that oil can be recovered from the waste soup of ramen noodles just after disposal as well as from the oily wastewater that spent one day in the grease trap. In the former case, EPR is 5.0, and the estimated amount of BDF is greater than 100 L/month for one restaurant. However, in the case of using the oily wastewater from the grease trap, EPR is less than 2.0 because of the reduction of yield of BDF due to a greater oxidation deterioration of the recovered oil, when the alkyl catalyst method is used. Therefore, it is desirable to recover oil from the oily wastewater at the drain pipe just after the sink.

In the laminar-turbulent transition process of a mixing layer formed downstream of a two-dimensional nozzle exit, an analysis was performed based on various information measures. Shannon entropy, permutation entropy and Kullback-Leibler divergence were introduced, and former studies in which they were used in the turbulent analysis were then reviewed. In the present study, the probability distribution of time series of hot-wire output voltage data was obtained, then analyzed. The aim of the investigation was to clarify the effectiveness of the analysis for the transition and turbulent flow. In addition, equations which Shannon entropy must satisfy in the turbulent flow field were derived. The Shannon entropy of the fluctuating velocity changed monotonically in the downstream direction. Thus, it appears to measure the transition process in the mixing layer. The permutation entropy of the fluctuating velocity first increased, then decreased, then increased again, and decreased finally. It reflected the increase of the fluctuating velocity and change of fluctuation manner (from periodic to irregular fluctuation) during the transition process. The Kullback-Leibler divergence based on the probability density function of the fluctuating velocity increased first, then decreased downstream, and thus did not show a monotonic change during the transition process in the mixing layer.

This paper describes the expansion of the measurable range of the temperature measurement method using a thermo-chromic liquid crystal. At first, we investigated the relationship between the profile of the spectrum intensity of the scattered light from the surface of the thermo-chromic liquid crystal and the temperature. A halogen light source with an infrared cutoff filter was used as the irradiation light source. Results show that the spectrum intensity of the scattered light increased monotonically with temperature in the range of wavelength shorter than 450nm, and the temperature could be identified by measuring the spectrum intensity of only a single specific narrow-band wavelength. The range of the measurable temperature of the method using this relation was validated using a monochrome-camera and narrow band-path filter of 442nm with FWHN=10nm. It was found that the measurable temperature range became about two times broader than that of conventional methods. In addition, the application of this method to the measurement of the two-dimensional temperature distribution was performed and temperatures with the range wider than that of conventional methods could be measured.

The complexity or randomness of the laminar-turbulent transition process of an inlet boundary layer in a circular pipe was analyzed by use of Kolmogorov complexity which is a very important measure of the randomness of various events. In the inlet region of the circular pipe, a jet that triggered a turbulent patch in the flow was periodically injected radially, and then propagated downstream periodically. Periodic velocity data which satisfies the phase constancy obtained from a hot-wire anemometer were compressed using a compression program running on a Windows PC. From the compressed data, the approximated Kolmogorov complexity, named AK, and normalized compression distance NCD were obtained. Although the distribution of AK of irregularly fluctuating velocity in the flow showed a slight discrepancy from the profile of fluctuating velocity intensity and intermittency factor, they exhibited qualitative consistency. Therefore, the objective judgment of the laminar-turbulent transition process based on the approximated Kolmogorov complexity mostly supports the conventional judgment. In conclusion, our study established the validity and usefulness of Kolmogorov complexity or algorithmic complexity to describe objectively the laminar-turbulent transition process in the mixing layer, flat plate boundary layer and pipe flow. With the aid of the AK we can distinguish the complexity within the turbulent region; on the other hand, the intermittency factor cannot.

A pressure type homogenizer consists of a plunger pump, and a valve part with a narrow channel. It generates effects such as a shear, a turbulent flow and a cavitation between fluid molecules at very short time, and makes a homogeneous emulsification state. If the flow pattern in a valve can be solved in more detail, the more efficient and stabilized emulsification will be attained. However, since it is difficult to measure the size, the pressure and the flow velocity in a narrow gap space by experiment, the details of the mechanism of emulsification by s shear, a turbulent flow, a cavitation and a collision have not been clarified enough. In this research, the size of gap is first calculated from the theoretical equation assumed to be laminar flow, based on the Reynolds number of the gap flow. Next, the pressure, the flow velocity, shearing stress, etc. are calculated. Then, the emulsification mechanism of each part of the valve is clarified by expressing the droplet size as a function of the gap size, the shearing stress and the exit velocity about two kinds of original solutions in which interfacial tension differs. Furthermore, the prediction expression of droplet size obtained by the emulsification is proposed.

Vortices occur when gas flow passes through a duct with a tube bank of the heat exchangers, such as a gas heater and a boiler. Very high level sound called a “self-sustained tone” occurs due to the interference of the vortices and the sound field in the duct. There are many investigations concerning the generation mechanism and countermeasures of the self-sustained tones. However there are few investigations focusing on the behaviors of the pressure and the velocity in occurrence of the self-sustained tones. In the past, we experienced the failure of the fan blade used in the experiment. In this paper, the experiment was carried out to examine the behaviors of the pressure and the velocity in the duct with tube bank. As a result, the static pressure changes along the squared curve when the self-sustained tone does not occur. But it suddenly rises up when the self-sustained tone occurs and it is possible for this pressure rise to cause the blade failure due to the generation of the rotating stall. In addition, it was clarified that the flow velocity does not increase in proportion to the inverter frequency and its gradient decreases when the self-sustained tone occurs.

The complexity or randomness was examined with the aid of Kolmogorov complexity for the flow about a turbulence wedge developed from a single roughness element on a flat plate. Velocity data obtained from a hot-wire anemometer and its time derivative data were compressed using a compression program running on a Windows PC. Approximated Kolmogorov complexity, AK, and normalized compression distance, NCD, were obtained. Although the AK variation of fluctuating velocity and that of its time derivative do not completely agree with that of the fluctuating velocity and the intermittency factor, they do roughly. Therefore, the objective judgment of the laminar-turbulent transition progress based on the Kolmogorov complexity mostly supports the judgment by the conventional intermittency factor. With the aid of the AK we can distinguish the complexity within the turbulent region; on the other hand, the intermittency factor cannot. The AK distribution of fluctuating velocity and that of time derivative are similar, and this suggests the similarity in the differentiation of complexity. The AK in the turbulent flow is larger than that in the non-turbulent flow. The AK decreases when the coherent structure has occurred in the turbulent flow. This means that the length of the algorithm is short if a computer expresses the coherent structure detected by the conventional method. Although the hot-wire signal within the coherent structure is random in appearance, it is coherent in the algorithm view. The difference in NCD on the time derivative of the fluctuating velocity between the turbulent and non-turbulent flow is larger than the NCD on the fluctuating velocity itself. That is, the difference in complexity appears in the fluctuating vorticity more than in the fluctuating velocity.

The acoustic material has been used inside ducts as a countermeasure of the self-sustained tone generated from heat exchangers and boilers. However the effects of the amount of acoustic material and its patching position in a lined duct on the acoustic damping in its duct have not been established. It can be expected that we can suggest the guideline of absorbing treatment at the design stage to avoid the generation of the self-sustained tone. In this study, the experiment and the analysis are carried out to clarify the problems mentioned above. First the usefulness of the analytical method by BEM is shown by comparing experimental results referring to the acoustic damping in the duct. Next, the effects of the amount of acoustic material and its patching position relative to the noise source on the acoustic damping in the duct are examined by BEM analysis. As a result, it was confirmed that the analytical method due to BEM was useful to predict the acoustic damping because the analytical results of acoustic damping were in good agreement with the experimental ones. And the acoustic damping was also clarified to be affected strongly by the positional relation between the noise source and the acoustic material. In addition, it was effective to patch the acoustic material near the noise source.

The article presents a study which evaluates the impact of laser welding on the attractive force and corrosion of a magnetic keeper installation. The study used the dental casting Au-Ag-Pd alloy and magnetic keeper. It shows that there was no significant difference of the attractive force in laser welding and conventional cast-on techniques.

The CBF, CMRO2 and CMRGlu were measured in patients with primary degenerative dementia including 5 patients with dementia of Alzheimer's type and 4 patients with Pick's disease, and then the correlation between the cerebral blood flow and energy metabolism was evaluated. The control subjects consisted of 5 age-matched normal volunteers. The CBF, CMRO2 and CMRGlu decreased in the bilateral frontal, temporal and parietal regions in the patients with Alzheimer's dementia, while they decreased in the bilateral frontal and temporal regions in the patients with Pick's disease. Both the CBF and CMRO2 were closely correlated with each other. However, the CMRGlu was more severely impaired than the CBF or CMRO2 in both pathological conditions. These results suggested that CMRGlu began to decrease before the reduction of the aerobic metabolism and thus measuring the CMRGlu is considered to be the most sensitive method for detecting abnormal regions in primary degenerative dementia.

We studied the serial changes of CMRGlu in 6 patients with dementia of Alzheimer type. All patients demonstrated moderately severe dementia at the initial PET scan. Serial PET scans were performed at an interval of 12 to 24 months. Five of the 6 patients showed a deterioration of clinical symptoms at the second scan. The global CMRGlu serially decreased in all patients. An asymmetry of CMRGlu in both the frontal and parietal regions was observed at the initial PET scan, while the direction of asymmetry was preserved at the second PET scan. The ratios (frontal/parietal and parietal/striatum) of CMRGlu showed no interval change. Therefore, CMRGlu was considered to decrease progressively throughout the entire brain in patients with moderately severe dementia of Alzheimer type.

A new rating method was designed to evaluate five symptoms of dementia; disorders of memory, cognition, language, visuospatial functions, and personality, which are defined as recent neuropsychological criteria for dementias by Cummings and Benson. Thirty-two items were made from the items of the Hasegawa dementia scale and neuropsychological tests. Scales for the five symptoms of dementia were then constituted of the items. In semi-structured interview, 113 demented patients and 16 normal elderly volunteers were rated. Interrater reliability of the five symptom scales were tested by ANOVA ICC and all the symptoms had a significant reliability. The scores of the five symptoms were correlated with each other and with the scores of the Hasegawa dementia scale. A Principal Component Analysis was applied to the scores of the five symptoms. The largest principal component had correlations with the scores of the Hasegawa dementia scale and the scores of the all five symptoms and was interpreted as a factor for severity of dementia. This component explains about 70% of total variance of the data. The other 30% of the variance were explained by four principal components which were interpreted as factors of the differences of the scores of the symptom scales. Relations between the scores of the symptoms and regional cerebral blood flow (rCBF) measured using SPECT were investigated in 25 moderately demented patients which met the criteria of probable Alzheimer's disease of NINCDS-ADRDA. rCBF was calculated as a ratio of 123I-IMP uptake of the areas to the mean uptake of right and left cerebellum. Significant correlations were found between the scores of memory symptom and the rCBF of the left temporal lobe (r = 0.59: p < 0.01) and between the scores of personality changes and the rCBF of the both frontal lobes (r = 0.58, 0.54: p < 0.01). Results suggest the possibility that the distribution of brain damage reflects symptoms in dementia and also supports the validity of analytic evaluation of dementia symptoms by this scale.

The time dependency of rCBF response to photic stimulation in the primary visual cortices was studied using H215O bolus-injection and PET. The subjects consisted of 5 normal volunteers aged from 25 to 40 years old. Their regional CBF was measured at 2 min and 7 min after the start of photic stimulation (frequency, 10 Hz). The percentage increases of rCBF were 19.6 +/- 7.9% (mean +/- SD, range: 8.9-27.6%) in the primary visual cortex on the left side and 23.2 +/- 13.6% (2.5-35.8%) on the right side at 2 min, respectively, while, in comparison, they were 25.3 +/- 20.0% (1.8-49.7%) on the left side and 25.3 +/- 16.4% (3.5-44.5%) on the right side at 7 min, respectively. No significant difference was found in the rCBF responses between at 2 min and 7 min. Therefore, the taming effect does not need to be considered when carrying out a photic stimulation study.

For the last ten years we had 56 patients operated for the empyema which occupied almost all the thoracic cavity. We evaluated their postoperative pulmonary functions and their sequelae. The pathological features of the resected lung and empyema wall were also examined. Surgical procedures consisted of 25 extraperiostal air plombage, 14 pleuropneumonectomy, 8 decortication, and 9 other procedures (lobectomy, muscle-flap, omental flap, and others). Preoperative %VC of patients with extraperiostal air plombage, those with pleuropneumonectomy, those with decortications and those with other procedures were 59.6 +/- 12.6, 46.4 +/- 11.1, 63.0 +/- 10.1, and 53.8 +/- 11.7 respectively. Of 11 patients who developed severe respiratory impairments (%VC less than 40 and/or FEV 1/VC predicted less than 30) post operatively, 4 had extraperiostal air plombage, 4 had pleuropneumonectomy, and 3 had other procedures. In general, degree of respiratory impairment was more severe in patients who underwent multiple surgical procedures. Of 18 patients who survived 5 years or more, %VC was under 50% in 9, and of those nine patients five had 30% decrease in VC compared to the preoperative values and there were 2 patients with extraperiostal air plombage in whom extreme shrinkage and deformity of hemithorax were observed though they had neither additional surgeries nor recurrences. Hemangioma was often seen on the walls of empyema and in some they became so large as to cause mediastinal shift. There were patients with round atelectasis, which, we thought, could have caused abscess or inflammatory granuloma.

The survival rates of 380 resected cases of lung cancer in our hospital were analyzed according to curability and histological cell type. The overall 5-year survival rate for stage I a cases was 64.5%, that for stage I b 52.3%, and that for stage II 26.7%. However, there were distinct differences in survival rates between stages I a-II with mediastinal lymph node dissection and those without mediastinal lymph node dissection. Of these 380 tumors, many were advanced (for instance, stage III tumors comprised 180 cases). T3 tumors had better prognosis (40.7% showing 5-year survival) than N2 tumors (26.7% showing 5-year survival). Among stage III tumors, squamous cell carcinoma (T3: 41%, N2: 36.7% showing 5-year survival) had a better prognosis than adenocarcinoma (T3: 16.1%, N2: 21.4%). T3N2 tumors, however, had such a poor prognosis that the value of surgery in these cases seemed questionable. Adjuvant therapy should therefore be evaluated accurately in future to improve prognosis. It was stressed that a randomized controlled study would be needed to evaluate the effectiveness of adjuvant therapy.

A new operative method named as "Extraperiosteal air plombage" against chronic empyema were performed to 80 patients and its cure rate by the first operation was 93.8% which is a good and high rate. Know-how to perform the operation without failure is (1) to complete the excoriation of the pleural debris, (2) to seal completely the leakage such as bronchiolar fistula, (3) to perform the extraperiosteal abbration rather over much to attach the lung to the muscle layer, (4) to close the chest wall completely, and (5) to wash out thoroughly the extraperiosteal cavity with brush and enough saline solution and to use the effective antibiotica.