自動制御系の設計に対する補助区間最適化法に関する研究

京都大学0048新制・課程博士工学博士甲第623号工博第105号新制||工||80(附属図書館)UT51-42-P37京都大学大学院工学研究科航空工学専攻(主査)教授 椹木 義一, 教授 近藤 文治, 教授 萩原 宏学位規則第5条第1項該当Kyoto UniversityDFA

Relationship between Wearing a Lead Apron and Work-related Musculoskeletal Disorders: A Questionnaire Survey of Japanese Radiological Technologists

The purpose of this study was to conduct a self-reported questionnaire survey of work-related musculoskeletal disorders (WMSDs) among Japanese radiological technologists (RTs) and to report on the relationship between wearing a lead apron and WMSDs. Between February and April of 2021, RTs in Okayama Prefecture, Japan, were surveyed by mail and through a website. Information on individual characteristics, physical factors at work, and the presence of WMSDs were collected. All participants were also asked whether they frequently wore lead aprons. A multiple logistic regression analysis was used to assess the relationship between wearing a lead apron and WMSDs. The model was adjusted for age, sex, body mass index (BMI), and working hours. Of the 123 participants, 67 (54.5%) had WMSDs. Multiple logistic regression analysis revealed that WMSDs were significantly associated with wearing a lead apron. Compared to the “Never wear” group, the odds ratios for the “Always/Frequently wear” and “Sometimes/Rarely wear” groups were 7.87 (95% confidence interval [CI]=1.28-48.46; p=0.026) and 7.80 (95% CI=1.43-42.44; p=0.017), respectively. Our analysis suggests that wearing a lead apron is associated with WMSDs, and thus design modifications in lead aprons may improve the occupational health management of RTs

On the Sub-Interval Optimization Technique for Final-Value Control Systems with Magnitude Constraint

A method of designing optimal final value-control systems with magnitude constraint is presented in this paper. A second-order linear dynamical system is considered here as a controlled plant. The magnitude constraint is preassigned on the control variable without assigning any penalties on the performance criterion. The optimal final-value control problem is formulated as a two point boundary value problem, and a physically meaningful solution is obtained by introducing a new concept of sub-interval optimization technique which avoids the direct solution of the two point boundary value problem. The method presented here, can be applied to the other types of optimal control problems with magnitude constraint

Increase of total alkalinity due to shoaling of aragonite saturation horizon in the Pacific and Indian Oceans: influence of anthropogenic carbon inputs

Aragonite Saturation Horizon (ASH) shallowed significantly by 25 to 155 m and 16 to 124 m in the Pacific and Indian Ocean respectively in two decades. Apparent Oxygen Utilization (AOU) increased by 3 to 34 and 0.5 to 31.5 μmol kg−1 in the Pacific and Indian Ocean respectively at the depth of ASH during this period. DIC increased by 12.5 to 36.8 and 5.5 to 32 μmol kg−1 in the vicinity of ASH in the Pacific and Indian Ocean respectively due to combined effect of increased anthropogenic CO2 and change in AOU. TA increased significantly by 5 to 10 and 4 to 9.2 μmol kg−1 in the Pacific and Indian Oceans respectively at the ASH most likely as a result of aragonite dissolution. The upward migration of ASH solely due to anthropogenic CO2 amounted to 6 to 58 m in the Pacific and 4 to 44 m in the Indian Ocean

Adsorption and removal of strontium in aqueous solution by synthetic hydroxyapatite

Hydroxyapatite (HAP) is a main mineral constituent of bone and tooth and has an outstanding biocompatibility. HAP is a possible sorbent for heavy metals in wastewater due to its high adsorption capacity and low water solubility. We developed a removal system of 90Sr from aqueous solution by HAP column procedure. More than 90 % of 90Sr was adsorbed and removed from the 90Sr containing solution. Divalent cations, Ca2+, had little effect on the removal of 90Sr up to a concentration of 1 mmol L−1. This clearly indicates that the HAP column technique is advantageous with respect to the capacity to adsorb 90Sr from water present in the environment

An Assessment of Radioactivity Levels of 210Pb and 40K in Tobacco and Radiation Exposure from Smoking

No research has been conducted on the radiation influence of tobacco on the alimentary system, although there have been some previous works on the respiratory system. In this study, the radioactive concentrations of 210Pb and 40K in a cigarette sample were first measured. The transfer factors of the nuclides from tobacco into smoke and solution (saliva and/or alcohol) were then examined. Moreover, the radiation doses from smoke inhalation were also evaluated. The radioactive concentrations of 210Pb and 40K in the cigarette tobacco were 0.01 and 0.3 Bq/cigarette. Since this 210Pb activity and the 210Po activity previously reported for the same sample were comparable, it can be concluded that there was a radioactive equilibrium between the 2 nuclides. The observed transfer factor of 210Pb (12%) into smoke was almost the same as that of 40K (15%), whereas the reported value for 210Po (60%) was significantly higher. The radiation doses due to inhalation of cigarette smoke varied from organ to organ, depending on the organotropic properties of the nuclide. For example, the kidneys, respiratory tract, and spleen showed relatively high doses from 210Pb and 210Po. The leaching rates indicated an inconsistent tendency related to solution types. This result could suggest that alcohol drinking, which is common in smokers, does not especially enhance the leaching characteristics

Proliferating Giant Pigmented Nevus: A Report of an Unusual Tumor Occurring in Association with a Congenital Giant Pigmented Nevus

A 32-year-old Japanese woman with a giant pigmented congenital nevus of the torso presented with a massive pigmented tumor mass of the vulva which grew over an 8-year period. Histologically, the tumor was composed of benign appearing nevus-like cells with focal areas of extensive fibrous response. The tumor cells were positive for S-100 protein and with an antihuman melanoma antibody (MoAb 225, 28S) stain. Electron microscopy confirmed the nevomelanocytic nature of the tumor cells and demonstrated peculiar cytoplasmic crystalline tubular structures similar to those seen in cells infected with herpes virus type II. We propose the term “proliferating giant pigmented nevus” for this previous undescribed tumor. J Invest Dermatol 92:315S–317S, 198

Immunohistochemical Analysis of Antimelanoma Monoclonal Antibodies, with Special Reference to Fetal Tissue Distribution

An immunohistochemical study using 2 antihuman melanoma monoclonal antibodies designated as MoAb 225.28S and MoAb 653.40S was carried out on various human skin tumors, including malignant melanoma as well as on normal and fetal tissues by indirect immunofluorescence technique. Specific immunofluorescence was observed not only in malignant melanoma cells but also in cells of pigmented nevi, basal cell epithelioma, normal hair follicles, and some fetal tissues. Both monoclonal antibodies were revealed to be able to recognize the common antigenic determinant shared by several skin tumors, including malignant melanoma, and fetal tissues. Therefore, both monoclonal antibodies might recognize premature antigen of both melanocytic and keratinocytic cell lineage