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This study adopts behavioural contract theory through a mathematical model and clarifies the situation in which a fixed–salary contract is preferable to an incentives–based one for the principal. T...

This study explores the effect of financial managers’ organizational identity (OI) on improving financial performance under fixed salary contracts and balanced budget restrictions in Japanese local governments (LGs). LGs enter compensation contracts based on fixed salaries with financial managers and demonstrate a strict fiscal policy based on balanced budget restrictions. How and under what conditions should OI contribute to improving financial performance in LGs? In the context of financial managers in Japanese LGs, we place organizational identities using the principal (mayor)–agent (financial manager) model under fixed salary contracts and a strict fiscal policy. Our mathematical results reveal that the impact of OI on financial performance in LGs depends on the extent of a strict fiscal policy and the reserve fund. Studying 452 survey responses of financial managers in Japanese LGs, we find evidence consistent with our hypotheses based on the theoretical model. The result contributes to management and government accounting studies by showing that the extent of financial policies and the reserve fund are drivers for OI to work effectively on improving financial performance in governments.

This study explores the effect of employee organizational identity on developing effective compensation contracts to improve organizational performance. We adopt the economic identity theory to mathematically model and test this model using data from a Japanese listed firm that uses an exogenous, uniform incentive scheme based on a seniority system. Situating low-level sales managers as agents and department managers as principals in the mathematical analysis reveals that when organizations do not set optimal compensation contracts, the expected utility of department managers is not high — even if they have high levels of organizational identity — because utility depends on the magnitude of incentive coefficients. Empirical results show that the coefficient of organizational identity has a significant positive relationship with organizational performance. However, surprisingly, when the incentive coefficient is high, the relationship between organizational identity and performance is negative. These results indicate that organizational identity is a “double-edged sword” in incentive schemes with a seniority system, and managers should tune their targets and incentive schemes more finely to optimize firm performance.

Because of effective machining operations with a very small amount of cutting fluids, near-dry machining attracts increasing attentions for environmental and economical benefits. MQL machining has so far been recognized as the most representative near-dry method and it is highly successful in machining of most ordinary steels. Recent concern for environmentally friendly manufacturing further encourages the attempts at applying near-dry operations to machining of difficult-to-cut materials. Since titanium alloys are typical difficult-to-cut materials, this paper investigates the cutting performance of various near-dry methods in turning of a titanium alloy from the view point of elongating the tool life. Those near-dry operations include supply methods of regular MQL mist, coolant mist and hybrid mists, where the coolant mist is atomized water-soluble cutting fluid and hybrid mists are the mixture of MQL and coolant mists. The regular MQL operation provided longer tool life than that of dry machining. In addition, compared with MQL machining, the hybrid mist operations could further extend tool life and, in particular, the single coolant mist operations demonstrated the possibility of making the tool life longer than that of ordinary wet machining with flood cutting fluid supply.

Near-dry machining attracts increasing attentions for environmental and economical benefits, and MQL machining has been recognized as the most representative near-dry method. It is highly successful in machining of most ordinary steels, and synthetic biodegradable polyol esters play a significant role as an effective cutting fluid with a very small amount. Recent concern for environmentally friendly manufacturing further encourages the attempts at applying near-dry operations to machining of difficult-to-cut materials. Since titanium alloys are typical difficult-to-cut materials, this paper investigates the cutting performance of various near-dry methods in turning of a titanium alloy from the view point of elongating the tool life. Those near-dry methods include regular MQL and hybrid mist supply operations, where the hybrid mist is a mixture of MQL mist and coolant mist which is atomized water-soluble cutting fluid. The regular MQL operation provided considerably long tool life compared with that of dry machining and the hybrid mist operation showed the possibility of making the tool life longer. The cutting performance was largely influenced by the type of MQL lubricants. In particular, a synthetic polyol ester lubricant having low viscosity indicated the successful cutting performance when it was combined with the coolant mist supply in the hybrid mist application.

In minimal quantity lubrication (MQL) machining of aluminum alloys, since they have highly adhesive characteristics, more effective lubrication is necessary. This study therefore proposes that oxygen-including compounds, such as esters, alcohols and acids, are considered to be a potential MQL lubricant. The experimental investigations have shown the cutting performance of those oxygen-including compounds has greatly been influenced by their chemical structures. Some of them have been able to provide the successful cutting performance as a MQL cutting fluid and, in particular, specific alcohols have demonstrated the superior anti-adhesive characteristics in MQL end milling.

MQL technique has been recognized as the most representative method of environmentally friendly near-dry machining. In machining of aluminum and its alloys, since they have highly adhesive characteristics, effective lubrication is often necessary and MQL machining sometimes finds difficulty. This paper therefore investigates the lubricating action of MQL media with various compositions in machining of aluminum. Detailed examination regarding the contents of carrier gases has demonstrated oxygen leads to the low cutting performance and its concentration in carrier gases has to be kept below the level between 1% and 10% to attain successful MQL machining of aluminum. Further, increasing the amount of MQL lubricant supply by boosting the air pressure is the efficient and convenient way to make MQL drilling of aluminum satisfactory.

Minimal quantity lubrication (MQL) machining typically uses several tens of milliliters per hour of cutting fluid: a very small quantity compared with generally several tens of thousands of milliliters per hour in the conventional flood supply of cutting fluids. MQL machining can reduce considerably the consumption of cutting fluids, so is a representative and successful environmentally friendly manufacturing operation. Specific synthetic polyol esters with high biodegradability, excellent oxidation stability, and satisfactory cutting performance were evaluated as optimal cutting fluids for MQL machining. The esters are required to work as an effective lubricant in the cutting zone in very small amounts, so the tribological actions are particularly important to improve the cutting performance. A controlled atmosphere cutting apparatus was devised to investigate the relationship between the tribological action and the practical cutting performance of the esters in MQL machining. A model ester and oxygen showed mutually enhanced adsorption activities for machining of steel by the efficient formation of an adsorption film which provided the lubricating effect and improved the cutting performance. In contrast, the presence of oxygen resulted in unfavorable cutting situations for machining of aluminum.

In the cold rolling of aluminum foil, coolants made with nonaromatic base oils provide poor lubricity compared with coolants made with conventional base oils. But there is no clear difference in lubricity between nonaromatic and conventional base oils in the case of the rolling of aluminum sheet. In evaluations of the adsorption activity of model base oil components, alkylbenzene with a longer alkyl chain shows the potential to enhance the adsorption activity of alcohol onto the nascent aluminum surface. In experimental rolling, furthermore, the lubrication performance of coolants using nonaromatic base oils can be improved with the addition of dodecylbenzene. The addition of 10 mass% of dodecylbenzene into a nonaromatic coolant is sufficient for practical lubrication performance in the cold rolling of aluminum.

This paper presents a new methodology for the adjustment of the preheating process and steady-state operation of electronic ballasts intended for hot-cathode fluorescent lamps. The classical series-resonant parallel-loaded half-bridge inverter is the power stage analyzed in this paper. In addition, the preheating process is based on the imposition of a constant rms current through the electrodes, in order to provide a proper value of the Rh/Rc ratio before the lamp start. According to the proposed methodology, it is possible to set suitable operating points for the electronic ballast, considering optimal conditions for the lamps electrodes. Therefore, the proposed methodology for setting the preheating and steady-state operation is a complete platform to the design of electronic ballasts for hot-cathode fluorescent lamps

This paper presents a new model for the representation of electrodes' filaments of hot-cathode fluorescent lamps, during preheating processes based on the injection of currents with constant root mean square (rms) values. The main improvement obtained with this model is the prediction of the Rh/Rc ratio during the preheating process, as a function of the preheating time and of the rms current injected in the electrodes. Using the proposed model, it is possible to obtain an estimate of the time interval and the current that should be provided by the electronic ballast, in order to ensure a suitable preheating process. This estimate of time and current can be used as input data in the design of electronic ballasts with programmed lamp start, permitting the prediction of the Rh/Rc ratio during the initial steps of the design (theoretical analysis and digital simulation). Therefore, the use of the proposed model permits to reduce the necessity of several empirical adjustments in the prototype, in order to set the operation of electronic ballasts during the preheating process. This fact reduces time and costs associated to the global design procedure of electronic ballasts

The tribological action of MQL media and atmospheric carrier gases was investigated using controlled atmosphere cutting apparatus. The investigation demonstrated their adsorption behavior onto metal surfaces was in close connection with the cutting performance of a lubricant synthetic ester and carrier gases in practical MQL machining. In particular, the presence of oxygen resulted in unfavorable cutting phenomena in MQL machining of aluminum. A unique technique of MQL media treatment was further proposed to prepare oil mist sprays containing microdroplets of water. This advanced technique provided some possibilities of improving the tribological action of MQL media in machining of aluminum.

Near-dry machining attracts increasing attentions for environmental and economical benefits. However, it has not been fully utilized in industry because of its premature stage of development and this situation has largely resulted from the lack of fundamental understanding of the tribological action regarding its lubrication media. In order to take a full advantage of near-dry machining, therefore, this study investigated basically the lubrication mechanism using orthogonal cutting in controlled atmospheres and carried out practical drilling with MQL system which is the most representative and successful near-dry operation. As a result, it was found that oxygen and ester adsorbed onto the nascent clean surface created by cutting, and the ester presented a high lubrication effect. Although adsorption of oxygen provided a preferable influence on cutting steel, it caused low performance when cutting aluminum alloy. In practical drilling, further, oxygen demonstrated a favorable influence on cutting steel and the presence of oxygen failed in drilling aluminum alloy.

As an optimal fluid for MQL machining, this paper introduces some synthetic polyol esters having the high biodegradability, excellent oxidation stability and satisfactory cutting performance. The fundamental investigation demonstrates synthetic esters possess the preferable adsorption ability on to the freshly cut metal surfaces and this ability can be enhanced by surrounding oxygen. This may result in effective lubricating film formation and is probably in close connection with their satisfactory MQL cutting performance. A multifunctional fluid, which is applicable to both machining and other lubricating parts of machine tools, is further developed based on the synthetic ester for MQL machining.

Adiabatic vertically downward air-water two-phase flows in a single channel commercial plate heat exchanger were visualized by a neutron radiography method to clarify the flow characteristics and the differences in liquid distribution from those of vertically upward flows. From the visualized results, it was shown that water fell down without a spreading at a lower gas volumetric flux and tended to flow in the left-side of the shortest pass between the inlet and exit. The liquid distribution was opposite to that of the upward flows in which liquid fraction was higher along the both side of the single channel. In the case of a higher gas volumetric flux above 7 m/s, liquid spread at the enlarged section and the liquid distribution in the main part of the heat exchanger seemed to be homogenous. Measured average void fractions for the air-water downward flows showed almost the same tendency as those for the upward flows, and those were well correlated based on Drift flux model. On the other hand, the frictional pressure loss of the downward flows showed lower values than those of the upward flows at the lower gas volumetric flux less than 13 m/s. The difference was might be caused by the difference in flow pattern. For the higher gas volumetric flux over 13 m/s, the difference in frictional pressure loss was a little. Frictional pressure loss was well correlated by L-M method.

Near-dry machining (NDM) is a technology with many ecological and economic benefits that uses very small amounts of metal working fluid (MWF). In order to increase the applications of this technology, the tribological mechanism during this process needs to be better understood. To accomplish this, two experimental set-ups were configured. The first involved a vacuum chamber where changes of gas near the cutting area can be traced by a mass spectrometer. The second has an atmospheric chamber where practical cutting can be done for cutting-performance comparison. Three gases - argon, nitrogen, and oxygen - were used with and without an ester in a series of orthogonal cutting tests to understand their roles in lubrication. It was found that oxygen adsorbs best onto a newly generated work surface and plays a significant role in promoting adsorption of the ester and, in turn, creating a lubrication film. Therefore, it is important to supply an abundant amount of oxygen in NDM to provide good lubrication conditions.

Adiabatic vertically downward air–water two-phase flows in a commercial plate heat exchanger were visualized by a neutron radiography method as a non-destructive test in order to clarify the flow characteristics and the differences of the liquid distributions from those of the vertically upward flows. Flow behaviors in a single channel and a multi-channel plate heat exchanger were investigated. From the visualized results of the flows in a single channel, it was shown that water fell down without a spreading at a lower gas volumetric flux of less than about 2 m/s. In the case of a higher gas volumetric flux above 2 m/s, liquid spread around the enlarged section and the liquid distribution in the main part of the heat exchanger seemed to be homogenous. Measured average void fractions for the air–water downward flows showed almost the same tendency as those for the upward flows in spite of the difference of the flow patterns. On the other hand, liquid distributions into 18 parallel channels were evaluated from the measured results of the liquid volumetric fractions in each channel. It was shown that the liquid distribution depended on the inlet liquid flow rate. However, the effect of the gas flow rate was a little. In the case of higher liquid flow rate, the liquid fraction became higher with a deeper channel due to a larger liquid momentum. However, in the case of a lower liquid flow rate, the opposite tendency was observed, i.e., the liquid fraction in the nearest channel to the inlet was higher.

Adiabatic air-water two-phase flows in a commercial plate heat exchanger were visualized by thermal neutron radiography method as a nondestructive test in order to clarify liquid distributions. Liquid distributions in a single channel and a multichannel plate heat exchanger were investigated. From the results of a single channel, it was shown that gas phase tended to flow at the center of the net-like conduit and liquid fraction at the both side was higher. However, in the case of higher gas volumetric flux above 19 m/s, liquid distributions seemed to be homogenous. Measured average void fractions were lower than those by the homogenous model. On the other hand, from the results of a multichannel, it was shown that liquid distribution into the each channel strongly depended on inlet conditions. In the case of higher liquid flow rate and lower gas flow rate, liquid fraction became higher with the deeper channel due to larger liquid momentum. However, in the case of lower liquid flow rate and higher gas flow rate, the opposite tendency of liquid distribution was observed, that is to say, liquid fraction was lower with the deeper channel.

We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin α2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin α2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin α2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin α2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin α2 on platelets might serve as a biological marker for the antitumor efficacy of E7820.

Machine tools generally necessitate a variety of lubricants. Since some of those lubricants are often contaminated with cutting fluids and disposed without adequate separation treatments, it must certainly be convenient to prepare a multifunctional fluid applicable to both machining and other lubricating parts. In minimal quantity lubrication (MQL) machining, synthetic polyol esters are the successful cutting lubricant. This study therefore proposes a certain synthetic ester as a base candidate of environmentally friendly multifunctional fluids. Several cutting and lubrication tests have demonstrated the successful multifunctional lubrication performance of this ester with a very small quantity of a highly effective additive.

Modern machining processes face continuous cost pressures and high quality expectations. To remain competitive a company must continually identify cost reduction opportunities in production, exploit economic opportunities, and continuously improve production processes. A key technology that represents cost saving opportunities related to cooling lubrication, and simultaneously improves the overall performance of cutting operations, is dry machining. The elimination of, or significant reduction in, cooling lubricants affects all components of a production system. A detailed analysis and adaptation of cutting parameters, cutting tools, machine tools and the production environment is mandatory to ensure an efficient process and successfully enable dry machining.

In semi-dry machining, such as minimal quantity lubrication (MQL) machining, a very small amount of a lubricant plays an Important role to achieve a successful operation. This study investigates the tribological behavior of lubricants for semi-dry application in connection with their cutting performance. In MQL turning, synthetic biodegradable esters are superior to a vegetable oil and provide the satisfactory cutting performance compared with a conventional cutting fluid of flood supply. Their tribological action is further evaluated with the aid of tool surface analysis and the adsorption characteristics of a model ester are fundamentally examined using a controlled atmosphere machining apparatus.

Borrelidin, an antibiotic with anti-angiogenic activity, not only suppresses new capillary tube formation, but also collapses formed capillary tubes in a rat aorta culture model. Since it selectively inhibits threonyl-tRNA synthetase, we examined the effect of threonine on its anti-angiogenic activity. We found that a high concentration of threonine (1 mM) attenuated the ability of borrelidin to inhibit both capillary tube formation in the rat aorta culture model and human umbilical vein endothelial cells (HUVEC) proliferation, yet did not affect the ability of borrelidin to collapse formed capillary tubes or to induce apoptosis in HUVEC. Borrelidin activated caspase-3 and -8, and inhibitors of both caspase-3 and -8 suppressed borrelidin-induced apoptosis in HUVEC. Taken together, these data suggest that the anti-angiogenic effects of borrelidin are mediated through at least two mechanisms, i.e. one threonine-dependent and the other threonine-independent, and borrelidin induces apoptosis in endothelial cells via the caspase-8/-3 pathway.