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We have started to develop a next-generation microwave radiometer to be used in millimeter-wave spectroscopy for the high-resolution and high-precision monitoring of water vapor behavior. The new radiometer will be suitable for not only space geodetic techniques such as VLBI and GNSS, but also field measurements to monitor, for example, volcanic activities and cumulonimbus cloud generation. The planned front-end system for our new microwave radiometer has a wide bandwidth feed of 20–60 GHz. A signal from the feed is separated into two linear orthogonal polarized signals using an orthomode transducer (OMT); one is in the 20–30 GHz feed and the other is in the 50–60 GHz feed. We are now planning to cool the wideband feed, OMT, and LNA for each signal at 77 K using a Stirling cryocooler to improve the signal-to-noise ratio. We assembled a room-temperature 20–30 GHz receiver without the cooling system until the middle of 2019 as a first step of our development. We implemented the new receiver into the 3.7 m dish at Okinawa Electromagnetic Technology Center, National Institute of Information and Communications Technology (NICT), and carried out the first measurements using this receiver for validation tests in October 2019. Quick-look data obtained by the new receiver shows good power signals for the expected receiving band of 18–28 GHz. We are now developing another receiver for a higher band of 50–60 GHz, and we are going to implement the second one into the new prototype radiometer by the end of this fiscal year.

This work investigates a functional estimation problem for single input single output linear and nonlinear systems, motivated by its enabling role in acceleration-based semi-active control. Solvability of a linear functional estimation problem is studied from a geometric approach, where the functional dynamics are derived, decomposed, and transformed to expose structural properties. This approach is extended to solve a challenging nonlinear functional observer problem, combining with the exact error linearization. Existence conditions of nonlinear functional observers are established. Simulation verifies existence conditions and demonstrates the effectiveness of the proposed functional observer designs.

Nowadays, investors, customers, and even suppliers focus on the bankability of photovoltaic (PV) technologies. However, few studies have investigated the annual net effect of solar spectrum. In this study, we estimate the net effect of the solar spectrum on the annual energy yield of c-Si and a-Si modules by two parameters. One parameter is a direct calculation from spectral factor (SF). The other parameter uses average photon energy (APE) and a regression line or curve. The estimations by the two parameters are quite consistent, whereas there is 1.2% difference between the estimations at most. Therefore, APE would be a useful index to quantify the effect of the solar spectrum.

A ride comfort of elevator system is one of the important factors to enhance the product value. Elevator lateral vibration is the main problem that affects ride comfort. In order to improve ride comfort, it is important to achieve an estimation and optimum design of the cage suspension system. In this paper, a time domain simulator for elevator lateral vibration is developed. We made detailed simulation models of roller guide system and slide guide system in order to evaluate ride comfort on the design stage. Comparing with the simulation results and experiment results, guide system behaviors under various conditions become clear. The simulation models are improved with these behaviors. Fine matching of simulation and experiment are confirmed with the improved models.

This paper considers the vibration reduction of transportation systems using semi-active actuators to improve the ride quality. Control design for the resultant semi-active system is difficult for nonlinear dynamics, constrained control, lack of performance-oriented nonlinear control design, and limited state information. A sub-optimal control structure is proposed to address the performance requirement by mimicking the optimal control. A specific sub-optimal control is provided and implemented with one measurement to reduce the hardware cost. Performance analysis of the sub-optimal control is investigated. The semi-active system with the sub-optimal control is simulated to demonstrate the effectiveness.

A rare case of the osteochondritis dissecans of the talus associated with giant cyst was reported.A 17-year-old girl, who had severe pain and swelling because of sprain of recurrent planterflexion and inversion force of the ankle in playing handball games, was seen. The antero-posterior, lateral and mortise roentgenography, and lateral tomography were taken, which revealed osteochondritis disscans of the talus with giant cyst in the body, as Stage III according to the Berndt and Hartys classiffication, including mild osteoarthrotic changes.The osteochondral fragment was excised with drilling after curettage by transmalleolar approach.The aetiology, diagnosis and treatment of this case compared with some references was discussed.

The cemented stems of two cases were revised with cementless stems of bipolar hip prosthesis. In one patient, the femoral shaft was perforated by the drill. In another patient, a fracture of upper medial site of the femoral shaft was recognized by postoperative roentgenogram. The fracture was due to unremoved bone cement conecting to the lateral part of inner surface of the femoral canal. Prevention of these complications needs meticulous attentions. For example, preparation of operative instruments, and the careful intraoperative procedure.

Pigmented villonodular synovitis (PVS) of the hip is a rare condition. The condition often presents radiological findings of the cysts in the femoral head and acetabulum.Bone is invaded and hip joint is destroyed. But the case wich showed rapid destrution of the joint is very rare.We report a case, a 71-year-old woman with PVS of the hip joint, in which bone was invaded and presented rapid destruction.

When we remove bile duct stones in endoscopic retrograde cholangiopancreatography, we sometimes encounter the complication of basket impaction. In most cases, bile duct stones can be crushed with a mechanical lithotriptor. An endotriptor also is commonly used to resolve the problem of basket impaction. An endotriptor is more powerful than a mechanical lithotriptor in crushing stones. We report a case of basket impaction that was not resolved by means of an endotriptor. When abdominal radiography shows apparent calcified bile duct stone, it should be cautioned that the stone is sometimes too hard to be crushed, even with use of the endotriptor as well as a mechanical lithotriptor.

In order to examine the feasibility of endoscopic microwave coagulation therapy (MCT) for the treatment of common bile duct cancer in humans, we investigated the safety and effectiveness of endoscopic MCT with the assistance of intraductal ultrasonography (IDUS). We performed MCT in the canine small intestine as a model because of its similarity in size to the obstructed human common bile duct. Multiple coagulation lesions were made in anesthetized dogs, with the endoscope inserted through a jejunostomy. Under condition "A", the tip of the MCT probe was kept in a fixed position in contact with the mucosa of the intestine, and coagulation was performed with an output of 30 or 50 W for 30 or 10 s, respectively. Under condition "B", the tip of the MCT probe was moved along the intestinal mucosa, and coagulation was performed with an output of 50, 40, or 30 W, all for 10 s. After coagulation, a thin-caliber ultrasonic probe was inserted endoscopically for observation of the effects of coagulation. Each coagulation under condition "A" resulted in degeneration of all layers of the intestine. Coagulation under condition "B" resulted in more localized degeneration, extending from the mucosal layer to the proper muscle layer. By comparison with histologic observations, the accuracy of IDUS in assessing depth of degeneration was 87.5%. Endoscopic microwave coagulation was considered safe and effective, and IDUS was able to accurately assess the effects of microwave coagulation.

Various photovoltaic (PV) technologies are commercially available today. The effect of solar spectrum on the performance of PV modules should be evaluated quantitatively in order to estimate the module performance with high accuracy and precision. Average photon energy (APE) has been frequently applied to evaluate the effect of solar spectrum. The purpose of this study is to enhance the precision and accuracy by introducing other indexes. In this study, we select solar spectra, the integrated spectral irradiance (ISI) and APE of which are equivalent to those of the standard AM1.5G spectrum. There is a slight difference in shape, although the shapes are approximately similar. We introduce one more index, which defines the spectral irradiance at the atmospheric window or the depth of the water absorption band. The introduction would further improve the accuracy and precision of the evaluation of the effect of solar spectrum.

In an elevator apparatus, an actuator for generating a vibration-damping force against the lateral vibration of a car is provided in parallel to elastic member for preventing the lateral vibration of the car. The actuator is controlled by a vibration-damping control unit. The vibration-damping control unit estimates a natural frequency of the lateral vibration of the car, determines a gain value on the basis of the estimated natural frequency and a rigidity value of the elastic member, and drives the actuator in accordance with an instruction signal obtained by multiplication of the determined gain value.

A vibration damping system for an elevator is provided with a damping device ( 5 ) that is provided between a cab ( 1 ) and a car frame ( 2 ) for supporting the cab ( 1 ) and whose damping coefficient can be changed. A speed detector detects the traveling speed of a reference elevator car, and a calculation unit ( 15 ) receiving the traveling speed detected by the speed detector calculates a control signal for the damping device ( 5 ), and outputs the control signal to the damping device. The calculation unit ( 15 ) controls the damping device ( 5 ) in such a way that, in the case where the traveling speed exceeds a predetermined value, the damping coefficient of the damping device ( 5 ) is larger than that in the case where the traveling speed is the same as or smaller than the predetermined value.

In a vibration damping device for an elevator, an actuator for generating a vibration damping force acting on an elevator car is provided in parallel with a spring for urging a guide roller against a guide rail. The actuator is controlled by a controller. The controller determines the vibration damping force to be generated by the actuator based on information from a car frame acceleration sensor for detecting horizontal acceleration of a car frame and a car cage acceleration sensor for detecting horizontal acceleration of a car cage.

Endoscopic microwave coagulation therapy for bile duct cancer with intraductal ultrasonographic monitoring: brief case report

An elevator vibration reducing device in which horizontal vibrations of a cage are detected by a vibration sensor. The cage is displaced horizontally by an actuator. A control portion for controlling the actuator has a computing portion for computing a vibration reduction control signal for reducing the horizontal vibrations of the cage based on a vibration detection signal generated by the vibration sensor. The control portion has a detection signal comparing portion for comparing a detection value obtained from the vibration detection signal with a previously set value, and stopping controlling of the actuator when the detection value becomes no less than the set value.

Bipolar hip arthroplasty was performed on 557 hips from December 1980 to June 1988. The clinical results and serial roentgenograms of 37 hips with acetabular deficiency, treated by arthroplasty from December 1980 to June 1983, were followed for a minimum of five years. The longest follow-up period was seven years and six months after the operation. The clinical score was assessed by the hip rating score of the Japanese Orthopaedic Association, which assigns a maximum of 100 points. The preoperative clinical score ranged from 24 to 56 points (mean, 42.2 points). The postoperative score improved to a range of 71-100 points (mean, 82.7 points). Of 37 hips examined, 31 hips were pain-free. As measured from the serial roentgenograms after the operation, the overall distance of central migration of the prosthesis in 37 hips was 0-5 mm, with an average of 1.4 mm, two years after the operation. At the five-year follow-up evaluation, 27 of 37 hips showed no additional central migration. The overall distance of superior migration of the prosthesis in 37 hips was from 0 to 8 mm, with an average of 2.6 mm, two years after the operation. Additional superior migration was noticed in 18 of 37 hips (48.6%) at the time of this five-year follow-up evaluation.

Activity measurements of 3H and 14C in several environmental samples around the incinerator for radioactive liquid scintillator waste at the Radioisotope Center, Kyushu University were carried out to estimate their levels. It was indicated that 3H and 14C concentrations in the atmosphere at 1 m from the outlet were about 0.2% of those estimated at the outlet, respectively. At 6 m away from the outlet, 3H concentration decreased to about one twentieth of that at 1 m and 14C concentration to background level. For soils and plants, 14C concentrations showed negligibly low values. The existence of these nuclides in particle form was not confirmed. It is considered that the result of the higher 3H concentrations as compared to 14C concentrations reflects not only the difference of the waste amounts of their nuclides, but also the discharge of 3H as moisture as well as water vapor.

Low back pain accompanied with degenerative lumbar spine is an important problem as well as cauda equina syndrome for lumbar spinal canal stenosis. The purpose of the surgical intervention is to decompress the neural stractures without spoiling stability of the lumbar spine. In point of this purpose, Wedge's osteotomy is one of the ideal methods for laminectomy. Multiple fenestration at the narrow interlaminar segments is a new method.We treated nineteen cases of the lumbar spinal canal stenosis surgically from 1982 o 1986 in our hospital. Central laminectomy was done in one case, Modified Wedge's osteotomy in eleven cases, multiple fenestration in five cases, anterior interbody fusion in two cases. Posterior spinal fusion was done in three cases of laminectomy, and in all cases of multiple fenestration. Harrignton distraction rod was employed in two cases, Harrignton compression rod in one case, and L-type rod in two cases.Good results were obtained concerning involvement of the cauda equina. But one case accompanied with cervical spondylotic myelopathy and one case with thoracic spinal cord tumor developed left paraparesis as sequelae due to spinal cord involvement. Low back pain was deteriorated postoperatively in two cases of laminectomy without fusion.One was a case of degenerative spondylolisthesis. In another one, postoperative stress ulcar occurred and long period of rest in bed was required.Instrumentation gave stability to the spinal column immediately after surgery and was able to make postoperative care easy.

Bipolar hip arthroplasties with bone grafts in acetabulums were performed in thirteen patients suffering from acetabular protrusion due to rheumatoid arthritis. Roentgenograms revealed sclerosing areas in new acetabulums. The sclerosing area expanded progressively with a thin radiolucent line adjacent to the outer head. Central migration of outer head stopped twelve months after surgery with appearance and spreading of sclerosis in new acetabulum. Until stop of migration, outer head has moved to upper direction by 2.7mm, upper-medial direction by 3.7mm and medial direction by 1.5mm. Finally, the mean width between joint surface and pelvic inner wall was 11.5mm. The sclerosis mey be an evidence of bone formation and incorpolation of grafted bone. Grafted bone exibited increased radionuclide activity. Incorpolation of grafted bone was confirmed by this study.

Allograft was used on a patient who was diagnosed as rheumatoid arthritis with severe acetabular protrusion. The acetabular deficiency was reconstructed with the allograft in bipolar hip arthroplasty. We employed a freezed femoral head as the allograft.Roentgenographically, bone trabeculae were passing the graft-acetabular junction in medio-inferior region.Bone scans showed increased activity in the allograft near the host-donor junction at an early stage and maintain high activity up to date.Partial incorporation and high radioactivity suggest that this allograft will be incorporated completely at the early date.

Acute ligamentous injuries to the knee joint should be diagnosed in the early stage, and proper surgical repair will result in a satisfactory recovery of the knee function, if the instability is not remarkable. A follow-up study was made of 36 patients with acute ligamentous injuries to the knee joint in our clinic, 16 of whom were treated surgically and the rest conservatively. Treatment of isolated ligamentous injuries provides good results without any problems during ADL and sports activies. The patients with combined ligamentous injuries should be surgically treated; however some of them could not return to full sports activities. So, careful management is necessary in treating acute ligamentous injuries to the knee joint.

Recently, we experienced a case of cervical myelopathy due to calcification of the yellow ligament. A 64-year-old woman was admitted to our climic with complaint of gait disturbance. Myelogram showed an incomplete block at C5/6 level by calcifying mass of the yellow ligament. En-block laminectomy was performed. Pathologically, there was no ossification in the lesion.

Extradural hemangiolipomas are rare tumors, which account for about 0.14% of the spinal tumors. We have experienced a case of hemangiolipoma. A male patient aged 49 was admitted to our hospital with complaints of the progressive sensory/motor disturbances and dysuria. Myelography and Metrizamide CT revealed extradural tumor. Total excision of the lesion was performed. Histological diagnosis was hemangiolipoma. In order to prevent postoperative instability of the spine, Harrignton compression rods were used and iliac bone graft was added. Clinical signs were dramatically improved after the operation.

We presented one case of aneurys mal bone cyst (a relatively rare condition) in the fifth lumbar vertebra, The patient was a 16 years old girl. Her chief complaint was low back pain. Destructive changes were proved radiologically in the fifth lumbar vertebral body showing soap bubble pattern or ballooned-out appearance.After curettage of the lesion and bone grafting in the involved area of the vertebral body through the posterior approach, reconstructive surgery of the lumbar spine was done by a posteroJateral fusion and spinal instrumentation in the lumboscral region.Seven months postoperatively, she was almost free of complaints showing a solid bony fusion in the fusion area of the lumbosacral region on the X-ray film.

Periosteal chondroma is an uncommon benign tumor, arising from the periosteal or parosteal tissue. A case of periosteal chondroma is presented in this paper. The patient was fifteen-year-old boy and was reffered to our clinic with chief complaint of tumor formation and pain in the middle part of his left upper arm. Radiological examination revealed a cortical indentation with juxtacortical soft-tissue mass, that was overlying on the shallow cortical indentation. En-block excision of the tumor was performed with bone grafting into the bone defect. Recurrence was suspected at the time of radiological check about nine months after surgery.

Bipolar hip arthroplasty with bone grafting was performed on 25 joints with rheumatoid arthritis from 1981 to 1985. The results and roentgenographical progress of the grafted bone were followed for a minimum of two years, the longest follow-up examination occurring six years after the operation. The clinical score was assessed by the hip rating score of the Japanese Orthopaedic Association, which assigns a maximum of 100 points. The preoperative clinical score ranged from 22 to 59 points (mean, 42.6). The postoperative score improved to a range of 65-92 points (mean, 72.8). Of 24 hips examined, 21 (87.5%) were painless. As measured serially from the roentgenograms made immediately after the operation, the overall distance of central migration in 24 hips was 0-8.5 mm (average, 2.7 mm). The overall distance of superior migration in 24 hips was 0-10 mm (average, 3.7 mm). A single massive bone graft using extracted femoral head was considered to be better than bone fragments as the procedure for acetabular reconstruction during bipolar hip arthroplasty in rheumatoid arthritis.