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41.
This paper describes a low‐cost version of a full‐duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built‐in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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43.
The effect of material non-linearity on large lateral deformations of fabrics structures was studied. Fixing the boundaries, the deformation under uniform internal pressure was analyzed by nonlinear FEM (Finite Element Method). Because non-linear elasticity was found in the tensile testing of fabrics, the non-linear tensile characteristic was also considered in the FEM. Some experiments were conducted under various fixed conditions and the displacement was measured by a laser displacement sensor. The calculated results considering the non linear tensile elasticity of materials were found to agree with the experimental ones. Thus the validity of the proposed calculation method was proven.  相似文献   
44.
This study measured air exchange rates, indoor concentrations of aldehydes and volatile organic compounds (VOCs), and radioactivity levels at 19 temporary houses in different temporary housing estate constructed in Minamisoma City following the Great East Japan Earthquake. The 19 surveyed houses represented all of the companies assigned to construct temporary houses in that Minamisoma City. Data were collected shortly after construction and before occupation, from August 2011 to January 2012. Mean air exchange rates in the temporary houses were 0.28/h, with no variation according to housing types and construction date. Mean indoor concentrations of formaldehyde, acetaldehyde, toluene, ethylbenzene, m/p‐xylene, o‐xylene, styrene, p‐dichlorobenzene, tetradecane, and total VOCs (TVOCs) were 29.2, 72.7, 14.6, 6.35, 3.05, 1.81, 7.29, 14.3, 8.32, and 901 μg/m3, respectively. The levels of acetaldehyde and TVOCs exceeded the indoor guideline (48 μg/m3) and interim target (400 μg/m3) in more than half of the 31 rooms tested. In addition to guideline chemicals, terpenes (α‐pinene and d‐limonene) and acetic esters (butyl acetate and ethyl acetate) were often detected in these houses. The indoor radiation levels measured by a Geiger–Müller tube (Mean: 0.22 μSv/h) were lower than those recorded outdoors (Mean: 0.42 μSv/h), although the shielding effect of the houses was less than for other types of buildings.  相似文献   
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46.
PURPOSE: The purpose of this study was to analyze the effects of lesion site and epithelial keratinization on the morphologic characteristics of odontogenic cysts and clarify determinate factors for cyst morphology. MATERIAL AND METHODS: Computed tomographic images of 92 odontogenic cysts were analyzed: 31 primordial, 31 dentigerous and 30 radicular. Thirty-four cysts were located in the maxilla (6 primordial, 10 dentigerous, and 18 radicular) and 58 in the mandible (25 primordial, 21 dentigerous, and 12 radicular). Histologically, 31 cysts showed epithelial keratinization (18 primordial and 13 dentigerous). No keratinization was seen in radicular cysts. The morphologic features of cysts were assessed by measuring long length parallel to dental arch and short length vertical to it and calculating the long/short ratio. In addition, the computed tomography pattern of the cyst was classified into unilocular, lobulated, and multilocular patterns. Appearance of the sclerotic rim and surrounding cortex were classified into three and four patterns respectively to evaluate the developmental features of the cyst. RESULTS: As a whole, the long length of the primordial cysts was statistically larger than the other two cyst groups and resulted in a larger long/short ratio. Statistical differences of CT pattern were also seen among cyst groups. There was no preference in any cyst group for the appearance of the sclerotic rim and cortex. There were statistical differences between maxilla and mandible in short axis and long/short ratio. The maxillary cysts generally showed round shapes irrespective of their histologic characteristics. A multilocular pattern was more frequent in the keratinized group of mandibular primordial cysts. In dentigerous cysts, a multilocular pattern was seen only in the keratinized group and the long/short ratio was statistically larger; cyst shape was elliptical along the long axis. CONCLUSION: Our results demonstrated morphologic differences of odontogenic cysts caused by lesion site and keratinization. The dentigerous cyst with predominant keratinization should be included in the primordial cyst (odontogenic keratocyst) group.  相似文献   
47.
A female child with dicentric translocation between chromosome 9 and chromosome 18 presented non-specific minor anomalies with laryngomalacia. Chromosomal analyses were performed by the G-banding method and a fluorescence in situ hybridization (FISH) technique with a specific probe for the centromeric region of chromosome 18 and the painting probe for the chromosomes 9 and 18. Her full karyotype was confirmed as 45,XX,tdic(9;18)(p24;p11). This is the first case of dicentric translocation between chromosomes 9 and 18. The FISH technique is an important tool in chromosome diagnostics.  相似文献   
48.
A conversion efficiency of 12.65% was obtained at AM-1.5, 100 mW/cm2 for a single p-i-n junction amorphous-Si solar cell of 1.05 cm2, with a glass/SnO2/p-i-n/back-electrode structure. The solar cell had a short-circuit current of 19.13 mA/cm2, an open-circuit voltage of 0.885 V, and a fill factor of 74.7%. The reason why the efficiency of the produced solar cell was enhanced by hot-annealing treatment is considered to be due to the reduction of the minute leaks caused by the pinhole treatment and the reduction of the number of pinholes by reverse-bias annealing treatment. It is believed that because of the minute irregularities on the surface of SnO2, the diffuse light in the solar cell increased the effective optical length in the i layer. Therefore the collection efficiency in the long-wavelength region was enhanced  相似文献   
49.
Preoperative evaluation of the operative indication of hepatic resection using the parameters obtained by 99mTc-GSA scintigraphy has been done. In particular, the accurate evaluation of the postoperative hepatic functional reserve essentially depends on these parameters. In the present study, a preoperative evaluation of postoperative hepatic functional reserve using 99mTc-GSA scintigraphy was performed in our operated cases retrospectively. PATIENTS AND METHODS: Thirty-eight patients who underwent hepatic resection were studied on 99mTc-GSA scintigraphy before and after operation. These patients were divided into two groups. Group A; had no postoperative complications (n = 31). Group B; had some postoperative complications (n = 7). Preoperative parameters of 99mTc-GSA liver scintigraphy (HH15, LU15) were calculated from the activities of liver and cardiac ROIs at 5 and 15 minutes after injection. The resection ratio (RR) was obtained by comparing the liver volumes which were calculated from the pre- and postoperative SPECT studies. The resectability indices (Res) were as follows: Res (LU15) = LU15 x (100-RR(%)/100, Res (HH15) = (1/HH15) x (100-RR (%)/100. RESULTS: There were statistically significant differences in the distribution of Res between A and B groups (p = 0.002, Mann-Whitney test). The values of Res, of which half of patients have complication, were 1.10 (Res (HH15)) and 16.4 (Res (LU15)). CONCLUSION: The resectability indices using 99mTc-GSA liver scintigraphy are useful for the preoperative evaluation of the limitation of hepatic resection.  相似文献   
50.
Right facial nerve palsy in a 58-year-old woman was due to sarcoidosis demonstrated by Gd-DTPA enhanced MRI. Abnormal enhancement of the right VIIth cranial nerve in the distal internal acoustic canal was seen on MRI. The enhancing lesion was smaller after 1 month of prednisolone 50 mg day-1. This is the first report on facial nerve involvement in neurosarcoidosis examined by Gd-DTPA enhanced MRI. The use of Gd-DTPA enhanced MRI with thin slicing, e.g. 3 mm slice thickness and 1 mm interslice gap, is effective in detecting small extramedullary lesions.  相似文献   
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