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Search Results: 1 - 10 of 1438 matches for " Hideki Moriyama "
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Study on Surface Heat Budget of Various Pavements for Urban Heat Island Mitigation
Hideki Takebayashi,Masakazu Moriyama
Advances in Materials Science and Engineering , 2012, DOI: 10.1155/2012/523051
Abstract: The surface heat budgets of various pavement surfaces are studied with the aim of mitigating the urban heat island effect. In this study, the thermal characteristics of pavements are examined using data from observations. The net radiation, surface temperature, temperature under the surface, conduction heat flux, and core weight for each experimental surface are recorded, together with the weather conditions at the time of observation. The latent heat flux is estimated from the observed weight of the cores. The surface heat budget under the same weather conditions is examined, and the sensible heat flux from each target surface is calculated. The parameters that influence the surface heat budget, for example, solar reflectance (albedo), evaporative efficiency, heat conductivity, and heat capacity, are examined. On a typical summer day, the maximum reduction in the sensible heat flux from that on a normal asphalt surface is about 150?W/m2 for an asphalt surface with water-retaining material and about 100?W/m2 for a cement concrete surface with water-retaining material, depending on the albedo of each surface. 1. Introduction The purpose of this study is to investigate the urban heat island mitigation effect achieved by conversion from an asphalt pavement surface to another pavement surface for ground surface improvement, which is an established urban heat island mitigation technique. Various kinds of pavements were constructed experimentally for the purpose of investigating their effect on urban heat island mitigation by analyzing the surface heat budget. The urban heat island mitigation effect is discussed from the viewpoint of the sensible heat flux reduction for each pavement. Urban heat island mitigation technologies focus on the improvement of urban surface materials on roads, roofs, and walls. For example, roads and roofs coated with high-reflectance paint are called cool roofs and cool pavements by Akbari et al. [1]. According to their estimates, the annual balances in the saving in cooling cost and the increase in heating cost obtained by introducing cool roofs are $35 million in Los Angeles, $16 million in New York, and $10 million in Chicago. However, fewer studies have been carried out on roads as compared to those on green roofs [2–7], green parks [8–12], and green plantings [13–15]. In Japan, several studies have been carried out to evaluate the performance of pavements designed to have a beneficial environmental impact [16–20]. However, those studies have evaluated each technology separately and discussed only the reduction in surface
Single-Incision Robotic Surgery  [PDF]
Norihiko Ishikawa, Masahiko Kawaguchi, Hideki Moriyama, Go Watanabe
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.32015
Abstract: Introduction: Single Incision Laparoscopic Surgery (SILSTM) has been developed as a less invasive laparoscopic surgery. On the other hand, robotically assisted surgical technology has offered new options for minimally invasive surgery. In this study, we report a new surgical technology to perform SILS using the da Vinci S surgical system (Intuitive Surgical Inc., Sunnyvale, CA). Materials and Surgical Technique: A porcine liver with gallbladder was placed on an endoscopic surgery trainer, and a 25 mm incision was made for one robotic camera and two instruments at the umbilicus position. Both instruments were crossed while preventing them from colliding with each other, and Robot-assisted single-incision cholecyctectomy was perfumed. Discussion: This technique is expected to contribute to the development of a number of procedures in the future.
Laparoscopic Hernioplasty Using Omega-3 Coating Mesh  [PDF]
Masahiko Kawaguchi, Norihiko Ishikawa, Youji Nishida, Hideki Moriyama, Masahiro Kaneki, Go Watanabe
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.38077
Abstract: Background: Laparoscopic hernioplasty has gained popularity with significant advances in prostheses. Omega-3 coating mesh (C-Qur) is a prosthesis that can be used in the abdominal cavity, and the coating prevents adhesion of the mesh to the viscera. We planned a prospective observational study of laparoscopic hernioplasty using C-Qur. Methods: C-Qur was used in laparoscopic hernioplasty over the course of 1 year. We considered laparoscopic approaches as our primary treatment method for abdominal wall hernias. Although only a single incision was made for the majority of the laparoscopic hernioplasties, additional incisions were made when severe adhesions were encountered. For incisional or ventral hernias, a lateral lower incision was made. For inguinal hernias, an umbilical incision was made. Sex, age, diagnosis, number of incisions, additional incisions, morbidity, and follow-up period were evaluated. Results: Twenty-four patients who underwent surgery between May 2010 and April 2011 were included in this study. The median follow-up period was 14 months. The most common early complications included wound pain and edema; however, there were no persistent complications.
The da Vinci Surgical System versus the Radius Surgical System  [PDF]
Norihiko Ishikawa, Go Watanabe, Noriyuki Inaki, Hideki Moriyama, Masanari Shimada, Masahiko Kawaguchi
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.37070
Abstract: Objective: Kanazawa University introduced the da Vinci surgical system and the Radius surgical system. In this study, we compared the advantages and disadvantages of each system. Methods: The da Vinci system is a master-slave tele-manipulation system, which provides hi-resolution 3D images. The Radius system is pair of hand-guided surgical manipulators. In this study we focus on the operability of both instruments rather than their 3D optical systems. Results: The Radius was originally developed specifically focused on ligation and suturing with suture sizes bigger than 4-0, it is more effective, less expensive compared with the da Vinci. Although the da Vinci system is bulky, it allows surgeons to perform endoscopic surgeries only if ports are properly placed to prevent each arm from colliding with the other arms. A crucial difference between the Radius and the da Vinci is not limited to anastomose small vessels but is extended to multidirectional dissection. Currently, the cost including initial investment is the biggest issue; however, the da Vinci is absolutely necessary to implement delicate cardiac surgeries endoscopically and less-invasively. Early approval of robotic surgery by the government is urgently required in Japan. Conclusions: Although both the da Vinci and the Radius have endoscopic instruments with a multi-degree of freedom, applications need to be differentiated depending on the procedures and indications. Therefore, it can be clearly said that these unique innovative systems will never compete against each other.
Triplet chemotherapy with paclitaxel, gemcitabine, and cisplatin as second-line therapy for advanced urothelial carcinoma  [PDF]
Hideki Takeshita, Koji Chiba, Sachi Kitayama, Shingo Moriyama, Rika Omura, Akira Noro
Modern Chemotherapy (MC) , 2013, DOI: 10.4236/mc.2013.21001
Abstract: Background: Methotrexate, vinblastine, doxorubicin, and cisplatin regimen, and gemcitabine and cisplatin regimen are widely used for advanced or metastatic urothelial carcinomas (UCs). However, a standard treatment for patients who fail these firstline chemotherapies is unavailable. We examined the efficacy and safety of secondline paclitaxel, gemcitabine, and cisplatin (PCG) chemotherapy in Japanese patients. Methods: Between 2004 and 2010, 25 patients with metastatic UCs who failed to respond to platinumbased regimens were treated with PCG. They received intravenous paclitaxel (60 mg/m2) and gemcitabine (1000 mg/m2) on days 1 and 8, and cisplatin (70 mg/m2) on day 2 of every 21 day course. We retrospectively collected patients’ clinical and pathological data and evaluated adverse effects and survivals. Results: Patients underwent 95 PCG cycles in all (average, 3.8 cycles per patient). One patient (4%) achieved complete response, 5 (20%) showed partial response, 8 (42%) had disease stabilization, and 5 (26%) had disease progression. Median overall survival was 8.5 months. Neutropenia and thrombocytopenia of grade ≥ 3 were observed in 68% and 56% of patients, respectively. No treatment related death occurred. Multivariate analysis revealed that hemoglobin levels < 10 g/dL and estimated glomerular filtration rate < 60 mL/(min1.73 m2) were significant risk factors for overall survival. Conclusion: PCG chemotherapy in the secondline setting potentially contributed to good prognosis in selected patients with relatively significant but tolerable toxicity.
Laparoscopic Observations in Acquired Inguinal Hernia before and after Robotic-Assisted Laparoscopic Prostatectomy  [PDF]
Masahiko Kawaguchi, Yoshifumi Kadono, Masanari Shimada, Hideki Moriyama, Norihiko Ishikawa, Go Watanabe
Surgical Science (SS) , 2014, DOI: 10.4236/ss.2014.54030
Abstract: Background: The mechanism of the development of acquired inguinal hernia, especially indirect inguinal hernia, is not well known. Although anatomical studies have been performed to explain development of inguinal hernia, they have mainly involved autopsy or temporal findings at the time of hernioplasty. To elucidate the pattern of development of acquired inguinal hernia, we studied the occurrence of inguinal hernia after robotic-assisted laparoscopic prostatectomy (RALP). Methods: From March 2009 to November 2011, RALP for prostatic cancer was performed on 60 patients in our institute. The RALP was performed by one urologist using the da Vinci Surgical System. The postsurgical development of inguinal hernia was diagnosed based on patients’ symptoms. Seven patients were treated with laparoscopic hernioplasty, and one underwent mesh-plug repair. Using video recordings, the laparoscopic findings during RALP and laparoscopic hernioplasty were compared among all patients. Results: Seven of 59 patients (11.9%) developed an inguinal hernia. One patient had a pre-existing pantaloon inguinal hernia at the time of RALP. Eleven inguinal lesions in the seven patients who underwent laparoscopic hernioplasty were reviewed, and all were indirect inguinal hernias. Conclusion: A main factor in the development of inguinal hernia after RALP could be a combination of outer-side intact layers and inner-side hard scar of the inguinal ring, which seems like “out swing door”.
36-Month Follow-Up Study of Post-Intervention Chronic Heart Failure Patients  [PDF]
Haruka Otsu, Michiko Moriyama
Health (Health) , 2014, DOI: 10.4236/health.2014.67075
Abstract: Aim: Although numerous studies of disease management and case management of chronic heart failure (CHF) have been carried out, length of effectiveness after program commencement has not been examined, so we examined a follow-up study at 36 months after program commencement. Methods: Participants went for follow-up visits to one Japanese clinic which specializes in internal cardiovascular medicine and they were given diagnoses of CHF. 104 outpatients participated in this study and randomized control trial was implemented. An educational program was implemented for 6 months. The data were collected at baseline, 3, 6, 9, 12 months from both intervention and control groups and at 24 and 36 months from the intervention group. Results: There was significant improvement in New York Heart Association (NYHA) in the intervention group between baseline and 36 months. Improvement in weight monitoring and activities or exercise in the intervention group continued up to 36 months. Meanwhile, sodium restricted diets and quitting smoking and/or drinking depended on individual preference and it was difficult to make improvements in these areas. Conclusions: The educational program showed promise in preventing CHF outpatients from deteriorating significantly on a long-term basis as self-monitoring of activity and weight continued significantly and there were no participants with CHF who deteriorated in the intervention group at 36 months after program commencement, although the program aimed only to provide illness and self-management knowledge. On the other hand, future work will need to compare participants in this program to a control group over an extended period of time with consideration for relieving the burden of the control group.
Electricity Generation System with Piezoelectric Element Using Acoustic Radiation Energy  [PDF]
Hiroyuki Moriyama, Yuta Yamamura
Journal of Power and Energy Engineering (JPEE) , 2018, DOI: 10.4236/jpee.2018.610001
Abstract: In this study, a circular plate that is installing a piezoelectric element at its center is adopted as energy-harvesting system and is subjected to a harmonic point force. Because this system cannot avoid the influence of its acoustic radiation, the influence is considered theoretically using the equation of plate motion taking into account its radiation impedance and is estimated by the electricity generation efficiency, which is derived from the ratio of the electric power in the electricity generation and the mechanical power supplied to the plate. As a result, the efficiency is suppressed by the acoustic radiation from the plate, so that the efficiencies are so different in whether to take into consideration the radiation impedance or not. Because those results are verified by the electricity generation experiment and radiation acoustic energy has a hopeful prospect for improving the performance of this system, mechanical-acoustic coupling is used to make the most of the acoustic energy. Therefore, a cylinder that has the above plates at both ends is also adopted as the electricity generation system and mechanical-acoustic coupling is caused between the plate vibrations and an internal sound field into the cylindrical enclosure by subjecting one side of each plate to a harmonic point force. Then, the effect of coupling is evaluated by comparing with the efficiencies in the electricity generation system of only plate. Specifically, because the radiation impedance increases with the plate thickness, i.e., with the natural frequency of the plate, it is demonstrated that the effect of coupling becomes remarkable with increasing the thickness on the electricity generation efficiency.
Dynamic Effect of Low-Cost Entry on the Conduct Parameter: An Early-Stage Analysis of Southwest Airlines and America West Airlines  [PDF]
Hideki Murakami
Modern Economy (ME) , 2013, DOI: 10.4236/me.2013.44032
Abstract:

The purpose of this research is to investigate the dynamic changes in the competition between air carriers by applying a revised conduct parameter method. We examine the cases of Southwest Airlines and America West Airlines due to the availability of data. Our interests are in what fashion a low-cost carrier entered the market, how the rival reacted, and whether the fashions of competition between two types of air carrier remained stable as time passed. Our empirical results show that the fashions of competition fell between Cournot and “P = MC” competition, and competitive fashions were sometimes stable but sometimes not.

Efficient Frontier via Production Functions and Mechanization  [PDF]
Hideki Nakamura
American Journal of Operations Research (AJOR) , 2017, DOI: 10.4236/ajor.2017.71004
Abstract: This study attempts to reconcile data envelopment analysis (DEA) with the production function approach in economics. We examine not only the inputs of capital and labor, but also the ranges of these inputs in production process steps, and endogenously derive a Leontief production function. The Leontief production functions shift northeasterly owing to mechanization, which is the replacement of labor inputs by capital inputs in some steps. Consequently, we describe the efficient frontier as the convex hull of the Leontief production functions. Furthermore, we consider the possibility of efficient production below the efficient frontier.
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