Thermodynamic assessment of integrated heat recovery system combining exhaust-gas heat and cold energy for LNG regasification process in FSRU vessel

A thermodynamic assessment of an integrated heat recovery system, which simultaneously recovers both the cold energy of LNG released into seawater and the exhaust gas heat of diesel generator released into ambient air during the regasification process in a LNGFSRU vessel, has been carried out. For the LNG regasification unit consisting of two-stage heat exchangers, a primary Rankine cycle was applied as a typical power cycle of the type A for recovering cold energy to the first-stage heat exchanger. A secondary Rankine cycle of the type B was serially inserted between the first-stage and the second-stage heat exchangers for recovery of the remaining cold energy of preheated LNG. Then, in the type C, the exhaust gas, which had a relatively high temperature, was applied as the heat source of the secondary Rankine cycle, instead of seawater. In such a sequential procedure, the type C was finally suggested as an integrated heat recovery system, in which the seawater and exhaust gas were combined as the heat sources. When the net outputs produced from each heat recovery system were maximized by changing the pressure and mass flow rate of working fluid, the thermal efficiency of the integrated heat recovery system of the type C was η[subscript I,EG] = 0.0741. The results showed an improvement of approximately 13.3% (25.6%) in the thermal efficiency compared to the value of η[subscript I,SW] = 0.0654 ( η[subscript I] = 0.0590) for the conventional cold energy recovery system of the type B (the type A), which only used seawater as the heat source. Based on this finding, a possibility of utilizing the integrated heat recovery system with the combined cycle within the LNG-FSRU was confirmed.Ministry of Land, Tranport and and Maritime Affairs (Korea) (LNG Plant R&D center

Philosophy of Education and Education of Philosophy: Three Styles of Teaching Philosophy according to their Conceptions of Philosophy

This paper is presented at the 3rd iAPED International Conference on Teacher Education, Seoul National University, Korea, Oct. 24-25, 2002.What follow is an attempt to isolate the specificity of the nature of teaching and learning philosophy in which philosophy is seen as identical with or closely tied to a specific activity. Because philosophers who embrace one of certain views tend to think that learning and teaching this activity is a main aim of philosophical education, guidelines for teaching and learning practice are already implied by their own conceptions. However, discussions of the nature of the nature of the subject are conducted apart from debates about adequate teaching methods. In this paper, I want to examine how different conceptions are related to teaching philosophical practices, that is to say how methods of teaching philosophy can vary with these different conceptions of philosophy

Correlated Electronic Structures and the Phase Diagram of Hydrocarbon-based Superconductors

We have investigated correlated electronic structures and the phase diagram of electron-doped hydrocarbon molecular solids, based on the dynamical mean-field theory. We have found that the ground state of hydrocarbon-based superconductors such as electron-doped picene and coronene is a multi-band Fermi liquid, while that of non-superconducting electron-doped pentacene is a single-band Fermi liquid in the proximity of the metal-insulator transition. The size of the molecular orbital energy level splitting plays a key role in producing the superconductivity of electron-doped hydrocarbon solids. The multi-band nature of hydrocarbon solids would boost the superconductivity through the enhanced density of states at the Fermi level.X11910sciescopu

Observation of a kink during the formation of the Kondo resonance band in a heavy-fermion system

We have shown that the kink behavior in the spectral function of a heavy fermion can appear during the formation of the Kondo resonance (KR) band and the hybridization gap. We have investigated the heavy fermion compound CeCoGe2, using a combined approach of the density functional theory and the dynamical mean field theory. Low temperature T spectral functions show dispersive KR states, similarly to the recent experimental observation. During the evolution from the non-f conduction band state at high T to the dispersive KR band state at low T, which have topologically different band shapes, we have found the existence of kinks in the non-f spectral function near the Fermi level E-F. The observation of kink is clearly in correspondence with the multiple temperature scales of the formation of the KR band.X1186sciescopu

Comparative analysis of outcomes after multiport and single-port laparoscopic colectomy in emergency situations: Is single-port laparoscopic colectomy safe and feasible?

SummaryBackground/ObjectiveAlthough consensus has been reached on the superiority of laparoscopy for a majority of conditions underlying acute abdominal pain, the safety and feasibility of single-port laparoscopic colectomy (SPLC) in emergency situations have not been determined.MethodsA prospective electronic database of all emergency patients who underwent either multiport laparoscopic colectomy (MPLC) or SPLC between April 2006 and December 2014 was used to compare the surgical outcomes of these operative methods.ResultsDuring the study period, 31 MPLCs and 76 SPLCs were performed. These two operative methods resulted in similar operating times, transfusion amounts, lengths of stay, postoperative complications, attainment of lymph nodes, and proximal and distal cut margins. However, the SPLC group had a shorter time to first flatus (2.8±1.9 days vs. 3.8±1.5 days, p=0.005), earlier reinitiation of free oral fluids (3.2±2.1 days vs. 4.4±1.8 days, p=0.002), and lesser requirement of narcotic analgesics (2.5±3.9 times vs. 4.7±4.8 times, p=0.017).ConclusionSPLC could be a safe and effective alternative to MPLC, even in emergency situations when performed by surgeons who have overcome the learning curve associated with single-port laparoscopic techniques. The tendency toward earlier returns to bowel function and decreased incidence of postoperative analgesic use would be potential benefits of SPLC in emergency situations

Performance-Based Multiobjective Optimal Seismic Retrofit Method for a Steel Moment-Resisting Frame Considering the Life-Cycle Cost

This study proposes a performance-based multiobjective optimization seismic retrofit method for steel moment-resisting frames. The brittle joints of pre-Northridge steel moment-resisting frames are retrofitted to achieve ductility; the method involves determining the position and number of connections to be retrofitted. The optimal solution is determined by applying the nondominated sorting genetic algorithm-II (NSGA-II), which acts as a multiobjective seismic retrofit optimization technique. As objective functions, the initial cost for the connection retrofit and lifetime seismic damage cost were selected, and a seismic performance level below the 5% interstory drift ratio was employed as a constraint condition. The proposed method was applied to the SAC benchmark three- and nine-story buildings, and several Pareto solutions were obtained. The optimized retrofit solutions indicated that the lifetime seismic damage cost decreased as the initial retrofit cost increased. Although every Pareto solution existed within a seismic performance boundary set by a constraint function, the seismic performance tended to increase with the initial retrofit cost. Analysis and economic assessment of the relations among the initial retrofit cost, lifetime seismic damage cost, total cost, and seismic performance of the derived Pareto solution allow building owners to make seismic retrofit decisions more rationally

Characteristics of injury of the corticospinal tract and corticoreticular pathway in hemiparetic patients with putaminal hemorrhage

BACKGROUND: No study on the characteristics of injury of the corticospinal tract (CST) or corticoreticular pathway (CRP) in patients with putaminal hemorrhage has been reported. In this study, using diffusion tensor tractography, we attempted to investigate the characteristics of injury of the CST and CRP in hemiparetic patients with putaminal hemorrhage. METHOD: Fifty seven consecutive patients with putaminal hemorrhage and 57 healthy control subjects were recruited for this study. Diffusion tensor imaging was performed during the early period (8 ~ 30 days) after onset. We defined injury of the CST or CRP in terms of the configuration (discontinuation of a neural tract) or abnormal DTT parameters (the fractional anisotrophy value or fiber number was more than two standard deviations lower than that of normal control subjects). The Motricity Index, the modified Brunnstrom Classification, and the Functional Ambulation Categories were used for evaluation of motor function. RESULTS: Among 57 patients, injury of the CST was found in 41 patients (71.9%) and injury of the CRP was found in 50 patients (87.8%), respectively, and 37 patients (64.9%) had injury of both the CST and CRP. All three motor functions of patients with injury of both the CST and CRP were significantly lower than those of patients with injury of either the CST or CRP (p < 0.05). CONCLUSION: Our results indicate that the putaminal hemorrhage frequently accompanies injury of both the CST and CRP, and the CRP appears to be more vulnerable to putaminal hemorrhage than the CST. These findings suggest the necessity for evaluation of both the CRP and the CST in patients with putaminal hemorrhage

The orphan nuclear receptor SHP is a positive regulator of osteoblastic bone formation

The orphan nuclear receptor small heterodimer partner (SHP; NR0B2) interacts with a diverse array of transcription factors and regulates a variety of cellular events such as cell proliferation, differentiation, and metabolism. However, the role of SHP in bone formation has not yet been elucidated. SHP expression is significantly increased during osteoblast differentiation, and its expression is partially regulated by bone morphogenetic protein 2 (BMP-2), which plays an important role in bone formation. In our study, inhibition of SHP expression significantly repressed BMP-2-induced osteoblast differentiation and ectopic bone formation. In accordance with these in vitro and in vivo results, osteoblast differentiation in SHP −/− mice primary osteoblasts was significantly repressed, and the mice showed decreased bone mass resulting from decreased numbers of osteoblasts. Finally, SHP physically interacts and forms a complex with runt-related transcription factor 2 (Runx2) on the osteocalcin gene promoter, and overexpression of SHP increased Runx2 transactivity via competition with histone deacetylase 4 (HDAC4), an enzyme that inhibits DNA binding of Runx2 to its target genes. Taken together, these results indicate that SHP acts as a novel positive regulator of bone formation by augmenting osteoblast differentiation through regulation of the transcriptional activity of Runx2. © 2010 American Society for Bone and Mineral ResearchPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65055/1/90718_ftp.pd

Short-term calorie restriction ameliorates genomewide, age-related alterations in DNA methylation

DNA methylation plays major roles in many biological processes, including aging, carcinogenesis, and development. Analyses of DNA methylation using next-generation sequencing offer a new way to profile and compare methylomes across the genome in the context of aging. We explored genomewide DNA methylation and the effects of short-term calorie restriction (CR) on the methylome of aged rat kidney. Whole-genome methylation of kidney in young (6 months old), old (25 months old), and OCR (old with 4-week, short-term CR) rats was analyzed by methylated DNA immunoprecipitation and next-generation sequencing (MeDIP-Seq). CpG islands and repetitive regions were hypomethylated, but 5&apos;-UTR, exon, and 3&apos;-UTR hypermethylated in old and OCR rats. The methylation in the promoter and intron regions was decreased in old rats, but increased in OCR rats. Pathway enrichment analysis showed that the hypermethylated promoters in old rats were associated with degenerative phenotypes such as cancer and diabetes. The hypomethylated promoters in old rats related significantly to the chemokine signaling pathway. However, the pathways significantly enriched in old rats were not observed from the differentially methylated promoters in OCR rats. Thus, these findings suggest that short-term CR could partially ameliorate age-related methylation changes in promoters in old rats. From the epigenomic data, we propose that the hypermethylation found in the promoter regions of disease-related genes during aging may indicate increases in susceptibility to age-related diseases. Therefore, the CR-induced epigenetic changes that ameliorate age-dependent aberrant methylation may be important to CR&apos;s health-and life-prolonging effects.ope