Several medical textbooks emphasize that the complete isolation of an aneurysm from its surrounding tissues (e.g., the arteries) ensures successful clipping.

Although cutting the adhesion sharply along the center of the fibrous tissue represents the ideal and safest dissection method, tight and narrow adhesions may prevent the insertion of both micro-scissors and dissector blade. Therefore, we used a small piece of semi-dry cotton pad (Bemsheet XR® Kawamoto Co Ltd., Osaka) to expand the adhering arachnoid mater between the structures. Specifically, the cotton pad was inserted into the space adjacent to the adhesion. It then absorbed the fluid (i.e., cerebral spinal fluid), swelled, and slightly expanded the adhesion, allowing the surgeon to cut it with micro-scissors. Repeating this process ensured the complete dissection of the aneurysm from the adhering arteries. This technique could also be applied to adhesions between vessels and other structures, including nerves, brain parenchyma, and dura mater.

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A satellite image database was developed for global wetland mapping. A lot of JERS-1 OPS and SAR images were collected over 80 test sites. A database management system of client server type was constructed on the PC network. We can select suitable image combination by using this system which draw rectangle area or browse imagery of satellite on a blank map.

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Lake Kasumigaura is polluted by massive growth of blue green algae during a typical summer. Measuring a quantity of chlorophyll-a in the phytoplankton is of importance in tackling with the lake water pollution problem. In this paper, a remote sensing method to estimate distribution of rich chlorophyll-a concentration as well as suspended solids concentration which is important parameter of turbidity in lakes or inland seas is proposed.

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The shape of human tongue plays an important role in oral cavity functions such as speaking, chewing, swallowing, and breathing. In this study, the authors constructed a mathematical model of the tongue using the mass-spring model and simulated tongue deformation during vowel production. The viscoelasticity of tongue tissues are represented by the Kelvin-Voigt model. Contraction of lingual muscles are represented by a muscle model composed of a constractile component, springs, a damper, and mass. Incompressibility of muscles is an important factor that affects tongue shape. In this study, the potential energy function generated by compression of tissues is defined. Muscle incompressibility is modeled by minimizing the energy function in the deformation process. The authors simulated tongue deformation during Japanese vowel production. Tongue muscles are classified into eight groups, and the muscle length is defined based on an MR image. The results are in good agreement with the MR imaging results of deformation of the tongue in the sagittal plane. Further, this simulation can qualitatively represent tongue deformation in producing Japanese vowel “a”.

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本論文では,まず,火災前後の2時期のLandsat/TMデータを用いて,焼失域の特定に有効な波長帯について調べた。これにより,焼失域の特定には,近赤外域と短波長赤外域の波長帯が有効であるという結果が得られた。この結果から,既存の研究において火災後の回復過程の評価に用いられていた指標が,焼失域の特定においても有効であると考え,この指標をBAIと定義した。このBAIを用いた場合は,標高毎の大気の影響の差が小さいという結果が得られた。
BAIとNDVIとを被災程度別に比較し,BAIを用いることの有効性について検証した。BAIを用いた場合には,全ての被災程度間(激害・中害・無書)のBAI値に有意差があったのに対して,NDVIを用いた場合には,無害と中害の問に有意な差は無かった、,最後に,BAIを用いた焼失域マッピングと被災程度の分類を行った。その結果,現地踏査によって作成された焼失域図と比較すると若干の違いは確認されたが,NDVIを用いて特定した焼失域と比較すると,特定可能な面積は大きく向上しだ,被災程度の分類についても,検証エリア内では,高精度の分類を行うことができた。
このように,既存の研究で火災後の回復過程の評価に用いられていた指標が,焼失域把握にも有効であることが示された。
今後の課題としては,本論文で提案した手法の他地域での適用を検討することと,BAIと被災程度との関係をより明確にし,詳細な被災程度分類を行うことが挙げられる。

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There are two major methods for NOAA/AVHRR-based fire detection. These methods are the threshold method and the contextual method. Threshold method detects fire pixels by comparing the radiant temperature of each pixel to predetermined threshold values. Contextual method detects fire pixels by comparing the radiant temperature of each pixel to its surrounding pixels. In the present study, these NOAA/AVHRR-based fire detection methods were compared and evaluated. And the authors improved the contextual method for Russian Far East. The processes were ; (a) First, conventional contextual method and modified contextual method were compared and evaluated for application to large-scale forest fire, (b) Secondly, modified contextual method and threshold method were compared and evaluated. A burnt area map developed from Landsat/TM data was used to assess and validate the locations of fire pixels detected by each method. The results show that ; (a) modified contextual method was able to detect fire pixels that the conventional contextual method failed to identify, but modified contextual method was inferior to conventional contextual method in fire detection accuracy, (b) the number of detected fire pixels was more and fire detection accuracy was better by the contextual methods than by the threshold method.

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Mild cognitive impairment (MCI) is a precursor stage to dementia. It is necessary to understand the appropriate condition of MCI to prevent the progression of dementia. For MCI diagnosis, there is a study report on memory feature measured by a device, in addition to paper-based assessments. Motor sequence learning memory, a trait of memory feature could be used as an indicator to distinguish MCI. The purpose of this study was to develop a new method to distinguish MCI from an unimpaired condition. The data obtained from proposed method are intended to be applied to a decision tree approach to establish a classification algorithm by clarifying the variables required for classification. Sixty-seven subjects were examined in the study:a group of healthy young people, a group of healthy elderly people, and a group of people with MCI. The motor sequence learning memory was quantitatively evaluated with a visual tracking exercise using hand dexterity movement with the help of a grasping force control training device (iWakka). Sine waves were combined to create a synthetic wave for evaluation tasks. For the evaluation parameters, the difference between the target value and atonal value was used, as well as assignment accuracy and its distributed standard deviation. MCI was differentiated based on these variables. The result showed that the value obtained from iWakka was significantly lower in the elderly people with MCI compared with the other groups. Furthermore, the classification algorithm was created using a decision tree classification. The evaluation variables adopted were mAGF₈ and the learning rate. In addition, the decision tree classifier was validated in terms of the area under the curve (0.79), sensitivity (0.66), specificity (0.92). From these results, it can be concluded that the proposed method with iWakka is highly likely to provide useful information when classifying MCI.

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When humans swallow, swallowing sounds occur at the larynx. Since swallowing sounds can be measured noninvasively, these sounds are expected to be useful for testing swallowing ability. By analyzing these sounds, researchers have attempted to elucidate the mechanisms and the acoustic characteristics of the swallowing sounds. However, little research has been done which utilizes swallowing sounds to measure how much food or liquid is being swallowed. If the amount of food or drink being swallowed can be measured quantitatively, some diseases may be prevented by monitoring eating habits. The purpose of this research was to estimate the volume of water swallowed by analyzing swallowing sounds. First, swallowing sounds were recorded by applying a microphone on the skin surface above the thyroid cartilage when volumes of 5mL, 10mL and 15mL were swallowed by a subject. Fifty measurements were obtained. Second, signal processing methods such as smoothing, linear prediction analysis, Fourier transform and wavelet transform were applied to the swallowing sounds. Eighty-eight feature variables that may reflect the amount of water swallowed were obtained from the results. Using principal component analysis, the number of feature variables was reduced from 88 to 13. Finally, the estimated volume of water swallowed was evaluated using support vector machines. The volume of water was accurately identified with a probability of 72% for volumes between 5mL and 10mL, a probability of 84% for volumes between 10mL and 15mL, and a probability of 88% for volumes between 5mL and 15mL. When the same analysis was performed in several human subjects, the precision of classifying volume of water decreased, which may suggest individual differences in movements of the larynx and pharynx during swallowing.

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Cryosurgery is a treatment for cancer which destructs cells by freezing. In cryosurgery, cells are injured not only by freezing but also by vascular stasis. The vascular stasis caused by thrombosis necrotizes the surrounding non-targeted cells due to the lack of oxygen and nourishment. Inhibition of thrombus formation, the former phase of the vascular stasis, is required to prevent damaging normal cells around a tumor. By analysis of thrombus formation under low temperature, the temperature controlling method can be developed to form less thrombus. Foregoing studies simulate platelet aggregation based on distance between platelets. However, in cryosurgery, temperature dependency of blood-clotting factors' activity is required to be considered. The authors constructed a model consisting of vascular and extravascular tissues. The temperature distribution near the ice probe and vessel is simulated by using the finite difference method solving the energy equation. The cell necrosis areas were estimated by considering the freezing rate of water in the vascular endothelial cells. We also constructed a model considering the temperature dependency of bonding probability and simulated platelet aggregation to cell necrosis areas. The bonding between platelets is represented as a spring and a damper. The simulation with varied temperature around destructed area showed that platelet aggregation depending on temperature. By comparing simulation result with experimental data, it is suggested that the proposed model can represent thrombus formation.

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Ultrasonic diagnosis requires substantial experiences for both acquiring and reading echography. This paper describes a novel method for synthesizing ultrasound image with artifacts according to user's probe manipulation. The proposed method is a sample-based approach that stores pre-captured real echo images as a volume data set in which each voxel has multi-directional values. Output echography is synthesized by interpolating voxel values, considering spatial arrangement and directivity of the voxel values. Experimental results demonstrated spatially seamless echography synthesis and characteristic artifacts with various probe postures.

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According to visually impaired people, in addition to guiding and safety support, assistance regarding the choice of appropriate colors and patterns for their clothes is required. Even though they cannot see their clothes, the visually impaired want to make a good impression upon others. This sort of social and psychological support is important in enabling the visually impaired to live independently and be able to socialize. A system that can recognize colors and patterns present on clothes is required. Therefore, we have previously developed an algorithm for such a system. In this study, a smartphone is employed to make the system easy to use. It is important to choose a light source for color recognition. In our experiments, we test a system with a cover containing a light inside and another system using environmental lighting that does not require a cover. Since the system with the cover provides a higher accuracy rate of color correction than one using environmental lighting, we implement it into a smartphone and perform evaluation experiments. The results of the experiments indicate that the accuracy rate is about 75% in color recognition and about 83% in pattern recognition, respectively.

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This paper proposes a surgical assistance scheme, which enables to locate small cancer lesion using RFID (Radio Frequency Identification Tags). State-of-the-art systems for endoscopic surgery are expected to be capable of finding very small cancer lesions in the diagnostic imaging although such small lesions have been difficult to be identified for excision through an endoscope. To find such small lesions surely during endoscopic excision surgery, a new endoscope supporting system is desired. In our proposed system we use a RFID tag to label each small lesion part during diagnostic imaging, then use a RFID tag signal sensor antenna at the time of an operation and supports discovery of a lesion area. In this report, it is possible to estimate a small lesion area using the RFID tag system, which is composed of the signal sensor antenna and RFID tags. The measurement system using a RFID tag and 4 sensor-antennas was made as an experiment, and the experiment using phantom was conducted. As a result, the difference with a theoretical value of less than 40 mm of distance of a RFID tag and a sensor antenna and the value acquired in 10 mm of phantom thickness was less than 2 mm. Furthermore, the value acquired when moving the spatial relationship of a RFID tag and a sensor antenna 20 mm each in x, y and z was verified, and it was shown clearly that errors are a minimum of 2.6 mm and a maximum of 22 mm.

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Recently, in order to achieve the prevention or early detection of diseases, many studies have been carried out to measure physiological information in everyday life. The purpose of this study is to develop the mat-type device to measure physiological information fro6m the sole. ECG (Electrocardiogram) and PPG (Photoplethysmogram) that are the indices of the cardiovascular system were adopted as physiological information. ECG is measured by conductive coupling without using the paste and capacitive coupling that is able to obtain ECG and PPG with socks. PPG is obtained by measuring the reflected light to incident infrared light at periphery. PWV (Pulse wave velocity) which is the index of the arteriosclerosis is able to be calculated from ECG and PPG. The subjective experiment reveals that the developed system can measure ECG and PPG. In addition, the system can measure ECG and PPG in case of wearing socks. Moreover, by simultaneous measurement of blood pressure, PWV was calculated by the developed system and the good correlation was found between PWV and blood pressure. In addition, the experiment showed that the PWV were changed with the blood pressure changes due to exercise. Therefore, result of this experiment showed this system has the potential to monitor the condition of cardiovascular system, and suggested the possibility to estimate the blood pressure without compression by the cuff.

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