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A dual-comb spectroscopy (DCS) system uses two phase-locked optical frequency combs with a slight difference in the repetition frequency. The spectrum can be sampled in the optical frequency (OF) domain and reproduces the characteristics in the radio frequency (RF) domain through asynchronous optical sampling. Therefore, the DCS system shows great advantages in achieving precision spectral measurement. During application, the question of how to reserve the mutual coherence between the two combs is the key issue affecting the application of the DCS system. This paper focuses on a software algorithm used to realize the mutual coherence of the two combs. Therefore, a pair of free-running large anomalous dispersion fiber combs, with a center wavelength of approximately 1064 nm, was used. After the signal process, the absorption spectra of multiple species were simultaneously obtained (simulated using the reflective spectra of narrow-bandwidth fiber Bragg gratings, abbreviated as FBG). The signal-to-noise ratio (SNR) could reach 13.97 dB (25) during the 100 ms sampling time. In this study, the feasibility of the system was first verified through the simulation system; then, a principal demonstration experiment was successfully executed. The whole system was connected by the optical fiber without additional phase-locking equipment, showing promise as a potential solution for the low-cost and practical application of DCS systems. [ABSTRACT FROM AUTHOR]

A dual-comb spectroscopy (DCS) system uses two phase-locked optical frequency combs with a slight difference in the repetition frequency. The spectrum can be sampled in the optical frequency (OF) domain and reproduces the characteristics in the radio frequency (RF) domain through asynchronous optical sampling. Therefore, the DCS system shows great advantages in achieving precision spectral measurement. During application, the question of how to reserve the mutual coherence between the two combs is the key issue affecting the application of the DCS system. This paper focuses on a software algorithm used to realize the mutual coherence of the two combs. Therefore, a pair of free-running large anomalous dispersion fiber combs, with a center wavelength of approximately 1064 nm, was used. After the signal process, the absorption spectra of multiple species were simultaneously obtained (simulated using the reflective spectra of narrow-bandwidth fiber Bragg gratings, abbreviated as FBG). The signal-to-noise ratio (SNR) could reach 13.97 dB (25) during the 100 ms sampling time. In this study, the feasibility of the system was first verified through the simulation system; then, a principal demonstration experiment was successfully executed. The whole system was connected by the optical fiber without additional phase-locking equipment, showing promise as a potential solution for the low-cost and practical application of DCS systems.

• Thermal discomfort in a log house was assessed using a calibrated model. • Effective passive overheating prevention actions were identified for future climate. • Natural ventilation was the best-performing measure in reducing future overheating. • Building-related measures are of secondary importance under free-run operation. • Possibilities for future-proofing log houses are presented. This study aimed to identify the most effective passive design measures to prevent overheating in a log house in a temperate climate. The study was conducted with a calibrated thermal model under a future climate projection (SRES A2 scenario) utilising an EN 16798–1 adaptive comfort model for the building operated under free-run mode during summer. The effects of six building-related and three organisational measures on the projected future thermal comfort in the studied log house were evaluated. During 2011–2040 and 2041–2070, thermal insulation and thermal mass paired with natural ventilation with or without shading were among the best-performing combinations. During 2071–2100, three of the six best-performing combinations were thermal insulation and thermal mass paired with natural ventilation with or without shading. Comparing the first and the last periods, the most effective organisational measure reduced the operative temperature by an average of 0.35 or 0.34 °C in the first two periods and by 0.36 or 0.33 °C in the third period. By outlining the potential effectiveness of specific measures in preventing overheating discomfort under climate change conditions, the findings significantly contribute to climate change adaptation of log houses and buildings in general. These findings can be used as design guidelines for future buildings and to formulate future building regulations as well as a decision-making support for policy-makers. [ABSTRACT FROM AUTHOR]

In this letter, we demonstrate the performance of the Tm:YLF and Tm:YAP slab lasers in free running. Both slab crystals are a-cut with a doping concentration of 3 at.%. Under an incident pump power of 376 W, maximum output powers of 130 and 126 W are obtained from the Tm:YLF and Tm:YAP lasers with the emissions peaks at 1909.4 and 1990.4 nm, respectively. The corresponding optical conversion efficiency is 40.4% and 38% for the Tm:YLF and Tm:YAP lasers, with beam quality factor M2 of 389 and 228 in the x direction and 1.5 and 6.8 in the y direction, respectively. [ABSTRACT FROM AUTHOR]

Accurate determination of hydrodynamic derivatives, appearing in the equations of motion of a marine vehicle, is essential for the correct prediction of its manoeuvring performance. Solution of these equations leads to the simulation of the ship motions in the horizontal plane for a surface ship and thus helps in understanding its course stability, turning ability, rudder effectiveness and ship responsiveness. This paper presents the numerical simulation of the Planar Motion Mechanism test using RANS-based equation to obtain the hydrodynamic derivatives appearing in the equations of motion and to assess the manoeuvrability of a container ship using standard definitive manoeuvers. Experimental validation of the numerical test is carried out by conducting free running model tests in a manoeuvring basin. [ABSTRACT FROM AUTHOR]

Summary: This paper unveils two efficient free running (FR) quenching circuits with the aim of reducing quenching time (QT) to minimize avalanche charge. Likewise, one circuit is compactly designed with low power consumption, suitable for single‐photon avalanche diode (SPAD) with hold‐off time below 10 ns. In second circuit, tunable hold‐off and reset‐time are provided within a wide range without decreasing QT, which are desirable in many applications. Proper operation and circuit uncertainty is assessed by Monte Carlo analysis in a standard 90‐nm complementary metal‐oxide semiconductor (CMOS) technology. In a bid to do a comparison between previously reported circuits and the proposed circuits, they are simulated with same SPAD model and parameters and results corroborate the proposed circuits guarantee active quenching time (AQT) of below 1 ns. Proposed circuits with current and area consumption of 0.74 μA, 32 μm2 for 7‐ns dead time and 16.2 μA, 93 μm2 for 21‐ns dead time are more efficient in terms of QT, area, and power consumption in comparison with other works. [ABSTRACT FROM AUTHOR]

Single-day trawling is commercially practiced along Thoothukudi coast, involving a total of 275 trawlers of varying length range operated from Thoothukudi fishing harbour (8°47’N, 78°9.5’E). The trawlers can be classified in three categories: vessels with overall length (OAL) of 40–50′ (Type 1), OAL 50–60′ (Type 2) and OAL above 60′ (Type 3). Trawlers with OAL of 45′, 55′ and 65′ were selected for the study. Irrespective of the type of vessel, the power required for towing the net was found to be unnecessarily high. The excess power wasted due to faulty trawl designs in Type-1, Type-2 and Type-2 vessels was 55, 87 and 133 hp, respectively. While trawling with optimal trawl design would contribute only 28.67% of the brake horse power (BHP) of the Type 3 vessels, the existing design of trawl used in this type of vessels contributed as much as 50.83% of the BHP. The Type-1, Type-2 and Type-3 trawlers were found to operate with excess fuel consumption at the rate of 103, 212 and 418 L of diesel per cruise, respectively. Based on the annual fuel consumption, true total annual CO2 emission was estimated as 458 tons. The study revealed that the total fuel consumption can be reduced by 40% by optimizing the trawl design and reducing the free-running speed, free-running duration and trawling speed. Further, vessels with an OAL of 60′ and above may be permitted for multi-day fishing in distant waters after suitably limiting the number of fishing trips/month in order to minimize the fuel loss through free running.

The influence of light on mammalian physiology and behavior is due to the entrainment of circadian rhythms complemented with a direct modulation of light that would be unlikely an outcome of circadian system. In mammals, physiological and behavioral circadian rhythms are regulated by the suprachiasmatic nucleus (SCN) of the hypothalamus. This central control allows organisms to predict and anticipate environmental change, as well as to coordinate different rhythmic modalities within an individual. In adult mammals, direct retinal projections to the SCN are responsible for resetting and synchronizing physiological and behavioral rhythms to the light-dark (LD) cycle. Apart from its circadian effects, light also has direct effects on certain biological functions in such a way that the participation of the SCN would not be fundamental for this network. The objective of this review is to increase awareness, within the scientific community and commercial providers, of the fact that laboratory rodents can experience a number of adverse health and welfare outcomes attributed to commonly-used lighting conditions in animal facilities during routine husbandry and scientific procedures, widely considered as “environmentally friendly.” There is increasing evidence that exposure to dim light at night, as well as chronic constant darkness, challenges mammalian physiology and behavior resulting in disrupted circadian rhythms, neural death, a depressive-behavioral phenotype, cognitive impairment, and the deregulation of metabolic, physiological, and synaptic plasticity in both the short and long terms. The normal development and good health of laboratory rodents requires cyclical light entrainment, adapted to the solar cycle of day and night, with null light at night and safe illuminating qualities during the day. We therefore recommend increased awareness of the limited information available with regards to lighting conditions, and therefore that lighting protocols must be taken into consideration when designing experiments and duly highlighted in scientific papers. This practice will help to ensure the welfare of laboratory animals and increase the likelihood of producing reliable and reproducible results. [ABSTRACT FROM AUTHOR]

Purpose: Practising a power-type activity over years can shape the neuromuscular profile of athletes. This study aimed at comparing the neuromuscular profile of a non-trained group (NT, n = 10) to power athletes practising Parkour (= traceurs, group PK, n = 11), an activity consisting of jumping obstacles mostly in an urban landscape.Methods: Maximal isometric plantar flexion force (MVC) and rate of torque development (RTD) were evaluated, and neuromuscular function of triceps surae muscles was assessed and compared between groups through the analysis of evoked potentials from posterior tibial nerve stimulation.Results: PK group exhibited higher MVC force (131.3 ± 8.7 Nm) than NT (110.4 ± 9.6 Nm, P = 0.03) and higher RTD (489.1 ± 93 Nm/s) than NT (296.9 ± 81 Nm/s). At a nervous level, this greater performance was related to a greater voluntary activation level (PK: 96.8 ± 3.6%; NT: 91.5 ± 7.7%; P = 0.02) and soleus V-wave amplitude (P = 0.03), and a lower antagonist co-activation (P = 0.02) and rest soleus spinal excitability (PK Hmax/Mmax: 0.32 ± 0.13; NT: 0.58 ± 0.17; P < 0.001). At a muscular level, PK group exhibited higher mechanical twitch amplitude (PK: 13.42 ± 3.52 Nm; NT: 9.86 ± 4.38 Nm; P = 0.03) and electromechanical efficiency (P = 0.04).Conclusions: The greater maximal force production capacity of traceurs compared to untrained was underlain by nervous factors, such as greater descending command and greater ability to modulate the spinal excitability, but also by muscular factors such as greater excitation-contraction coupling efficiency. The high eccentric loads that characterize Parkour training may have led traceurs to exhibit such neuromuscular profile. [ABSTRACT FROM AUTHOR]

Some indices of food texture were not enough to reproduce the kinetic energy. Therefore, we developed a device and an index (Energy Texture Index, ETI) that enables one to measure the kinetic energy of vibration by the food fracture using a probe mass obtained by a free running. It enabled one to define another index (Food Friction Index, FFI) that was also proposed to measure a friction of probe against a food sample. The ETI and FFI were measured for apple, persimmon, and banana as examples. The ETI and FFI showed a characteristic difference between the three fruit samples. The FFI was found to be constant even if the insertion velocity into sample is changed. The ETI and FFI have possibilities to show a new facet of food texture. [ABSTRACT FROM AUTHOR]

Single-day trawling is commercially practiced along Thoothukudi coast, involving a total of 275 trawlers of varying length range operated from Thoothukudi fishing harbour (8°47’N, 78°9.5’E). The trawlers can be classified in three categories: vessels with overall length (OAL) of 40–50′ (Type 1), OAL 50–60′ (Type 2) and OAL above 60′ (Type 3). Trawlers with OAL of 45′, 55′ and 65′ were selected for the study. Irrespective of the type of vessel, the power required for towing the net was found to be unnecessarily high. The excess power wasted due to faulty trawl designs in Type-1, Type-2 and Type-2 vessels was 55, 87 and 133 hp, respectively. While trawling with optimal trawl design would contribute only 28.67% of the brake horse power (BHP) of the Type 3 vessels, the existing design of trawl used in this type of vessels contributed as much as 50.83% of the BHP. The Type-1, Type-2 and Type-3 trawlers were found to operate with excess fuel consumption at the rate of 103, 212 and 418 L of diesel per cruise, respectively. Based on the annual fuel consumption, true total annual CO2emission was estimated as 458 tons. The study revealed that the total fuel consumption can be reduced by 40% by optimizing the trawl design and reducing the free-running speed, free-running duration and trawling speed. Further, vessels with an OAL of 60′ and above may be permitted for multi-day fishing in distant waters after suitably limiting the number of fishing trips/month in order to minimize the fuel loss through free running. [ABSTRACT FROM AUTHOR]

As a part of the building design process, Estonian building code requires standardized dynamic hourly simulations to verify the building’s compliance to the summer thermal comfort requirements. In this study, we analysed this overheating assessment method for free-running residential buildings, by comparing the simulation results with measured data. Simulation models with different thermal zoning levels were studied: single-zone models, multi-zone apartment models and multi-zone whole building models. We analysed and quantified the effects of modelling detail and thermal zoning on indoor temperature and overheating estimation on the basis of five apartment buildings. Based on the results, a method, using indoor temperature measurements and outdoor climate data, to assess overheating risk has been proposed, as a relatively simple and inexpensive method for pre-defining the need for dynamic simulations. [ABSTRACT FROM AUTHOR]

Bow foils have the potential to significantly reduce engine load and C O 2 emissions of ships operating in waves. This paper presents the methodology and results of an improved free running experiment for the evaluation of bow foils. The model tests directly measured the change in ship delivered power in waves with and without a bow foil. The results show that the bow foil reduces the delivered power in regular head waves by up to 50% and 12% in irregular waves. In addition to quantifying the comparative contribution due to foil thrust and reduced ship motions in waves, the experiment measured the wave phasing and feathering parameters. The presented dataset, analysis and experimental procedures, which can be used for numerical validation and performance predictions in a range of conditions, demonstrates the potential of energy saving bow foils to reduce engine load and ship emissions. [ABSTRACT FROM AUTHOR]

The Parkour is a physical activity based on a proposal of Natural method (NM) and the Parcours Du Combattant (PDC). The aim was to review the historical aspects, and prime characteristics of the modality Parkour. George Hébert was the creator of MN, against the gymnastics and sports expertise. He has published the base of MN, using natural gestures and full physical development. The PDC idealized by Raymond Belle was adapted from MN and military training base. David Belle continued the legacy of his father, based on the concept that training should be applicable to real life and extreme situations. We concluded that the conceptual and historical aspects of Parkour are determinant to define its identity within the physical education's area. [ABSTRACT FROM AUTHOR]

Background. We studied the prevalence rate of exercise-induced bronchoconstriction (EIB) in Annaba schoolchildren. No previous assessment of this syndrome had ever been done in Algeria. Methods. EIB was evaluated using the 6 min free running test (6MFRT) on 286 children, 87.4% of whom were 10-12 years old. They performed the test in the morning, during the autumn--winter season. Peak expiratory flow rate (PEFR) was measured before, and then 5 and 10 min after the 6MFRT, a 15% or more decrease in post-exercise PEFR being defined as significant. Results. EIB was much more frequent in asthmatic than in nonasthmatic children (47.0% vs. 13.9%, p < .001) and the drop in PEFR was more marked among the former. EIB was observed more often in a cool temperature (<8°C). There were relatively more children who were either eutrophic or overweight among those presenting an EIB. Past histories of nocturnal wheezing and rhinoconjunctivitis presented respectively the best specificity (96.7%) and sensitivity (84.8%). Children of unemployed workers presented the highest occurrence of EIB. Passive smoking appeared as the only factor being related to EIB among the indoor pollutants. The prevalence rate of asthma (6.7%) was higher than in a previous cross-sectional epidemiological survey study performed in the Maghreb. The prevalence rate of EIB (13.9%) was situated in the upper range of the results given worldwide. Conclusions. These features of a fairly high bronchial hyperresponsiveness could be facilitated by the polluted environment of the city. [ABSTRACT FROM AUTHOR]

Air temperature thresholds are investigated and proposed for acceptable comfort in air-conditioned buildings. Using the ASHRAE database of field studies in which acceptability votes were obtained from occupants, it is shown that within the thresholds the acceptability is indistinguishable. Therefore, there is little gain from conditioning spaces to an 'optimum' air temperature, a practice that involves significant energy cost. However, beyond the thresholds there is a significant drop-off in acceptability. Ideally, air-conditioning would be used only when the environmental conditions are beyond the thresholds. The use of ceiling fans or personal environmental control systems broadens the threshold range. Thresholds are determined for both air-conditioned and ventilation-cooled buildings in the database. The equally acceptable range between the thresholds is 8-10 K in both types of buildings. It is possible that a perception of reduced air quality in warm environments could impose an upper temperature threshold. Perceived air quality is examined in two laboratory studies with air temperatures ranging from 18 to 30°C. Perceived air quality is seen to be closely correlated to thermal comfort rather than to temperature; as long as thermal comfort is maintained by air movement, perceived air quality will be acceptable. Relationships between temperature thresholds and productivity, operating set-points, and energy use are also discussed. Les seuils de temperature de l'air sont etudies et proposes pour un confort acceptable dans les immeubles climatises. En utilisant les etudes de terrain figurant dans la base de donnees de la Societe americaine des Ingenieurs en Chauffage, Refrigeration et Climatisation (ASHRAE), dans lesquelles il a ete obtenu de la part des occupants des reponses relatives a l'acceptabilite, il est montre que, dans la limite des seuils, l'acceptabilite n'est pas discernable. Il y a par consequent peu de benefice a climatiser des espaces a une temperature « optimale » de l'air ce qui entraine des frais significatifs. Cependant, au-dela des seuils, l'on constate une baisse sensible de l'acceptabilite. Dans l'ideal, la climatisation ne serait utilisee que lorsque les conditions environnementales depassent les seuils. L'utilisation de ventilateurs de plafond ou de systemes de controle individuel de l'environnement elargit la plage des seuils. Les seuils sont definis a la fois pour les immeubles climatises et les immeubles refroidis par ventilation figurant dans la base de donnees. La plage offrant une egale acceptabilite entre les seuils se situe a 8-10 K dans les deux types d'immeubles. Il est possible que la perception d'une reduction de la qualite de l'air dans des environnements chauds puisse imposer un seuil de temperature superieur. La qualite de l'air percue est examinee dans deux etudes de laboratoire pour des temperatures de l'air allant de 18 °C a 30 °C. Il apparait que la qualite de l'air percue est etroitement correlee au confort thermique plutot qu'a la temperature; tant que le confort thermique est maintenu par la circulation d'air, la qualite de l'air percue sera acceptable. Il est egalement discute des relations entre les seuils de temperature et la productivite, les points de consigne et l'utilisation de l'energie. Mots cles: confort adaptatif circulation d'air immeubles climatises fonctionnement libre controle individuel de l'environnement (CIE) acceptabilite thermique confort thermique [ABSTRACT FROM AUTHOR]

This paper presents an estimation method of rotational direction and speed for free-running ac machines driven by an inverter without speed and voltage sensor. The method has four estimation modes, and it utilizes only the measured phase current of machines. The performance of the proposed method is verified through the experiments for both permanent-magnet synchronous motor and asynchronous machines. [ABSTRACT FROM AUTHOR]

This case study describes a 14-year-old male suffering from significant academic and personal difficulties, who has been diagnosed with depression, schizotypal personality disorder, and learning disabilities. Because of excessive sleepiness, assessment for a potential sleep disorder was performed. An overnight polysomnographic study revealed no primary sleep disorders. Wrist actigraphy revealed a non-24-hour sleep-wake pattern. Delay in temperature rhythm and dissociation with melatonin rhythms were also noted. Treatment with oral melatonin restored normal sleep-wake schedule. In a follow-up psychiatric evaluation, none of the above diagnoses were present. Greater awareness of sleep disorders may prevent psychiatric misdiagnosis of treatable sleep-wake schedule disorders. [ABSTRACT FROM AUTHOR]

Abstract: The Mashona mole rat, Cryptomys darlingi, is a social, subterranean African rodent that is rarely, if ever, exposed to light, and that exhibits a regressed visual system. This study investigated locomotor activity patterns of Mashona mole rats (n=12) under different light cycles. Activity was measured using either infrared captors (n=8) or running wheels (n=4). The mole rats entrained their activity to a standard (LD 12:12) photoperiod. They displayed either a nocturnal or diurnal activity preference with one bout of activity and one bout of rest. Therefore, as a species, the Mashona mole rat did not show a clear nocturnal or diurnal activity preference. When the LD (12:12) light cycle was inversed, the animals switched their activity, too. Under constant dark (DD), most mole rats (73%) showed a free-running circadian activity rhythm, but under constant light (LL), only some (36%) did. The free-run period of the rhythm (τ) ranged from 23.83 to 24.10 h. The remaining animals were arrhythmic. There was large interindividual and intraindividual variations in the rate and extent of entrainment, time of activity preference, and activity patterns. Possible reasons for the observed variations are discussed. It is concluded that the Mashona mole rat has an endogenous activity rhythm which approximates 24 h, that the mole rat can distinguish between light and dark, and that the endogenous clock utilises this photic information as a zeitgeber. [Copyright &y& Elsevier]

Circadian rhythms in behavior, metabolism, and physiology are based upon transcriptional/translational feedback loops involving a core set of clock genes that interact to regulate their own expression. In mammals, the SCN is the site of a master biological clock regulating circadian locomotor rhythms. The products of the clock genes mPer1, mPer2, mCry1, and mCry2 form essential components of both negative and positive elements within the SCN oscillator. The primary aims of this study were to examine clock gene abundance under longterm LL in an attempt to provide molecular correlates of the lengthened tau and daily phase delays described by Aschoff's rule. Wheel-running behavior was recorded from mice maintained in either DD or LL for 50 days. The abundance of the clock genes mPer1, mPer2, mCry1, and mCry2 and their protein products was then examined (every ∼4 h) within the SCN using in situ hybridization and immunocytochemistry. Under LL conditions, mPer1, mPer2, mCry1, and mCry2 messages remained rhythmic, although the waveform of mCry2 was altered compared to DD. In LL, mPER1, mCRY1, and mCRY2 protein levels were also rhythmic and comparable to the patterns observed in DD. However, mPER2 is elevated and constitutively expressed under LL. Thus, rhythmic expression of these clock genes is not dependent on the rhythmic production of mPER2, and the acute up-regulation of mPer1 and mPer2 described for short (nonparametric) light pulses is not sustained under LL conditions. These findings suggest that mPER2 is important for the generation of phase delays in the molecular clockwork, providing a possible molecular explanation for Aschoff's rule: LL lengthens the circadian period by inhibiting the degeneration of mPER2, and constitutively elevated levels of mPER2 enhance the phase-delaying limb of the molecular oscillator. [ABSTRACT FROM AUTHOR]

Recent advances and new directions in quantum cascade (QC) lasers are discussed. Invented in 1994 following many years of research on band-structure engineered semiconductors and devices grown by molecular beam epitaxy, this fundamentally new laser has rapidly advanced to a leading position among midinfrared semiconductor lasers in terms of wavelength agility as well as power and temperature performance. Because of the cascaded structure, QC lasers have a slope efficiency proportional to the number of stages. Devices with 100 stages having a record peak power of 0.6 W at room temperature are reported. QC lasers in the AlInAs-GaInAs lattice matched to InP material system can now be designed to emit in the whole midinfrared range from 4 to 20 /spl mu/m by appropriately choosing the thickness of the quantum wells in the active region. Using strained AlInAs-GaInAs, wavelengths as short as 3.4 /spl mu/m have been produced. New results on QC lasers emitting at 19 /spl mu/m, the longest ever realized in a III-V semiconductor laser, are reported. These devices use innovative plasmon waveguides to greatly enhance the mode confinement factor, thereby reducing the thickness of the epitaxial material. By use of a distributed feedback (DFB) geometry, QC lasers show single-mode emission with a 30-dB side-mode suppression ratio. Broad continuous single-mode tuning by either temperature or current has been demonstrated in these DFB QC lasers at wavelengths in two atmospheric windows (3-5 and 8-13 /spl mu/m), with continuous-wave linewidths <1 MHz when free running and /spl sim/10 KHz with suitable locking to the side of a molecular transition. These devices have been used in a number of chemical sensing and spectroscopic applications, demonstrating the capability of detecting parts per billion in volume of several trace gases. Sophisticated band-structure engineering has allowed the design and demonstration of bidirectional lasers. These devices emit different wavelengths for oppos- ite bias polarities. The last section of the paper deals with the high-speed operation of QC lasers. Gain switching with pulse widths /spl sim/50 ps and active modelocking with a few picosecond-long pulses have been demonstrated. Finally, a new type of passive modelocking has been demonstrated in QC lasers, which relies on the giant and ultrafast optical Kerr effect of intersubband transitions. [ABSTRACT FROM PUBLISHER]

Engineering practice presents some impact of sloshing and ship motion interaction on added resistance in waves, and this paper is an attempt to figure out the effect of such impact through experiment while theoretical investigation is troubling scholars due to the complexity of this problem. A Liquefied Natural Gas (LNG) carrier scaled to 1/27.384, with one prismatic tank, is modeled for free running tests in regular head waves of 6 different wavelengths in the deepwater towing tank of China Scientific Research Center (CSSRC). For each wave case, the revolution rate of propeller, the ship speed, and corresponding torque and thrust are measured, and the added resistance is thereafter obtained by subtracting the still water resistance from the mean total resistance on assumption of a constant thrust deduction. The experimental results are comparatively discussed in conditions of sloshing and ballast weight. It is found that under current test conditions, internal sloshing affects ship motion by reducing its value, and the added resistance in waves decreases accordingly while the energy consumption decreases. The experimental results that liquid sloshing has an evident influence on the added resistance shall be a very important consideration for the development of green LNG cargos. • First success of testing on ship added resistance in waves considering sloshing using a free-running system. • First verification of engineering discovery of sloshing effect on ship added resistance in waves from model test. • The test results are of fatal values for designing and operating LNG carriers, and possible bases for future investigation. [ABSTRACT FROM AUTHOR]

• A novel multi-objective evaluation model for mass housing is formulated. • The model optimizes construction costs, embodied energy and indoor thermal comfort. • Composite layer envelop constructions are investigated in warm humid climate. • Best alternative envelop solutions are proposed for free running buildings. • Lean wall and roof constructions make repeated appearances in the solution sets. This study evaluates and compares the performance of the commonly constructed mass housing envelops in India with alternative building envelop constructions. These alternative construction scenarios are created with a material library comprising of the available alternative roofing and walling system combinations including some common emerging construction technologies standardized and advocated by the Building Materials and Technology Promotion Council of India. The common trend of housing envelop constructions in the country involves ordinary burnt brick walls and reinforced cement concrete roofing and beam-column system which is referred to as the base case building envelop in our study. We consider initial investment costs, thermal comfort perception and the initial embodied energy in a multi-objective evaluation framework for assessing free running building envelops. Rat trap bonded brick walls, glass fibre reinforced gypsum construction, light gauge framed steel (LGFS) constructions, monolithic concrete (MC) construction system, reinforced concrete ribbed roof and compressed stabilized earth block (CSEB) walls and CSEB filler roof slabs make repeated appearances in the multi-objective optimal solution sets or Pareto optimal solution sets. CSEB construction has lowest initial embodied energy, LGFS gives minimal thermal discomfort whereas MC construction system reports least construction cost. A predominance of lean envelop constructions is observed in the Pareto optimal solution sets considering minimization of construction cost, thermal discomfort and construction embodied energy. [ABSTRACT FROM AUTHOR]

Computations of the self-propulsion free running KCS model with 2DOF (heave and pitch) using four different propulsion models are presented. Computations are performed with HUST-Ship, in house URANS CFD code developed for ship hydrodynamics. PI speed controller is used to find the propeller rotational speed that could balance the thrust and resistance. Single-phase level-set approach is used for free surface simulation. Propulsion models include discretized propeller, the descriptive body force based on open water curve and simple Hough and Ordway approach, OUM (Osaka University Method) based on simplified quasi-steady two-dimensional BEMT (blade element momentum theory) and modified OUM based on BEMT considering three-dimensional viscous effects. Compared with OUM, modified OUM obtained the C L and C D from discretize propeller model open water characteristic CFD computation results so that the method could be more similar to the discretize propeller model. The computation conditions are same as the model test and the computational results show good match with model test data. The results show that considering the three-dimensional viscous effect of propellers can improve the simulation accuracy of propulsion model. The CFD computation results of open water characteristics show the modified OUM has less than 2% difference compared with the discretized propeller models and higher prediction accuracy than OUM. The self-propulsion free running computational results of thrust, velocity distribution, free-surface cuts and self-propulsion parameters using modified OUM model have been compared with EFD and discretized propeller model. • HUST-Ship is used successfully to simulate ship self-propulsion with four different propulsion models. • Modified OUM results are very close to discretized propeller and in good agreement with experiment. • Modified OUM shows higher accuracy than other two body force methods. [ABSTRACT FROM AUTHOR]

Parkour is an extreme sport that has been popular in Europe for a few years. This sport has now made it across the Atlantic and is quickly gaining popularity in the United States. Participants of this activity, known as parkouristes, try to overcome obstacles in their environment in the most efficient manner possible. This can be accomplished by simply jumping or scaling an obstacle, but sometimes this is done in a very acrobatic manner. The sport had a longtime underground following but has now gained media exposure through various television advertisements, and it has even been featured in recent blockbuster films. As a result, many amateurs are attempting to recreate these dangerous stunts without proper protection or guidance. We will review the case of an 18-year-old male who sustained multiple fracture/dislocations of his left foot while practicing parkour. ACFAS Level of Clinical Evidence: 4. [Copyright &y& Elsevier]