• Korean Journal of Food Science and Technology
• /
• v.24 no.5
• /
• pp.428-439
• /
• 1992

Drying process in a fixed bed red pepper dryer was modeled and simulated. Drying efficiency describing the effectiveness of energy usage in red pepper drying was defined as a ratio of energy used for moisture evaporation to total energy consumption, and expressed in combination of measurable temperature variables. The efficiency was compared with real evaporative efficiency and tested in the simulated and experimental drying. An overall drying efficiency was derived, and analyzed for various control variables consisting of drying temperature, air recycle ratio and air flow rate. Optimal operation conditions of drying was then searched by Box's complex method by using it as an objective function. Carotenoids retention was simulated and put as a constraint of product quality in the optimization. The optimization results gave that two staged drying operation could improve the ding efficiency compared with single staged drying. As a technique for further energy saving automatic termination of drying appeared feasible by monitoring an exit air temperature from dryer.

• Culinary science and hospitality research
• /
• v.1
• /
• pp.5-23
• /
• 1995

Management of kitchen is consist of various management factor, for instance, physical resources, financial resources, information resources, and human resources. Because these kind of resources determine efficiency of kitchen management, human resource management is important aspect of kitchen operation. In this paper of view, recently human resource management has been considered by kitchen manager. Kitchen Managers who are interested in human resource, focus on efficiency. Also human resource management underlined not only efficiency, but interrelationship of emplyee. Today, considering with the environment of management, operation of kitchen is important section on hotel management in relation to the profit of it. In the future, therefore kitchen will be strategic profit center on hotels. According to in this tendency, as profit business center kitchen assumed a aspect of efficiency mechanism. This thesis aimcs to point out the actual status of human resource management in the hotels, and suggests the improvement there of by analyzing the system. This research is organized into five sections. section one introduces its objectives. scope and mothodology. Section two provides the theory of human resource management on the kitchen of hotels. And section these analyzed about the factors of human resource management. Section four, suggests the alternatives of the improvement on human resource management, section Five describes the conclusion of this thesis. Today, importance of human resource is viewed multipoint aspects in relation to efficiency of organization and interrelationship of employee, especially the arrangement of human resource is fairly handle and allocation of the human resource and personal appraisal. On the other hand, human resource managers have to be responsible for the cost control and customer's attraction by developing human resources. In order to advance human resource management on kitchen of hotels, following alternatives are considered with efficiency of management and interrelation of employee. The first, the manager of hotels has to consider the passive support of development of human resource. The second, the manager of hotels should develop the various training program for the extonsive ability of employee. The third, in order to improvement of human resource management, manager should establish the system for human resource management view of efficiency and employee's interrelationship.

• Journal of Power Electronics
• /
• v.16 no.6
• /
• pp.2024-2034
• /
• 2016

This paper presents a DC-DC buck converter with a Phase-Locked Loop (PLL) that can compensates for power efficiency degradation over a wide input range. Its switching frequency is kept at 2 MHz and the delay difference between the High side driver and the Low side driver can be minimized with respect to Process, Voltage and Temperature (PVT) variations by adopting the PLL. The operation mode of the proposed DC-DC buck converter is automatically changed to Pulse Width Modulation (PWM) or PWM frequency modes according to the load condition (heavy load or light load) while supporting a maximum load current of up to 1.2 A. The PWM frequency mode is used to extend the CCM region under the light load condition for the PWM operation. As a result, high efficiency can be achieved under the light load condition by the PWM frequency mode and the delay compensation with the PLL. The proposed DC-DC buck converter is fabricated with a $0.18{\mu}m$ BCD process, and the die area is $3.96mm^2$. It is implemented to have over a 90 % efficiency at an output voltage of 5 V when the input range is between 8 V and 20 V. As a result, the variation in the power efficiency is less than 1 % and the maximum efficiency of the proposed DC-DC buck converter with the PLL is 95.4 %.

• Korea Real Estate Review
• /
• v.28 no.3
• /
• pp.37-52
• /
• 2018

This paper analyzed the relative efficiency of industrial complexes by type based on the DEA Model. In this analysis, the output and exports of 287 industrial complexes in 2017 were used as output variables, while the industrial land area and the number of employees in the same year were used as input variables. The results of the relative efficiency of industrial complexes by type were as follows: The relative efficiency of industrial complexes was affected mainly by type and the operating period of industrial complexes. In the types of industrial complexes, the most efficient industrial complex was the Urban, high-tech industrial complex, followed by the National industrial complex and the General industrial complex. Therefore, high-tech innovation and government support for industrial complexes would be necessary to increase the efficiency of industrial complexes. In the operation period of industrial complexes, relative efficiencies increased with longer operation periods. To maximize the regeneration effect of the old industrial complex, efficiency must be kept as a priority item of the old industrial complex regeneration project.

• New & Renewable Energy
• /
• v.4 no.2
• /
• pp.31-38
• /
• 2008

Using a surplus head in presented water supply pipes, we have studied to improve the operating efficiency of small hydro generator, which was chosen for a test model with 00 hydro power plant. With regard to power control and countermeasure of water hammer impact, Finally we have represented the optimal control method through the synthetical analysis of existing system symptoms, operation efficiency, the effect of water hammer impact and system configuration.

• Proceedings of the KIPE Conference
• /
• 2001.12a
• /
• pp.124-128
• /
• 2001

In this paper, a high-efficiency double-ended active clamp ZVS forward converter is proposed. This converter can be used in compact size AC/DC converter applications such as a notebook adapter. The principles of operation are described and the zero voltage switching characteristics are analyzed. High efficiency of this converter is verified by the experimental results.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.1222-1225
• /
• 2008

The power efficiency of a full-color OLED display decreases with long-term operation because of the material characteristics. The lifetime of the OLED display also decreases as the power efficiency declines. Therefore, this work provides a novel color difference algorithm to improve the power consumption and extend the OLED lifetime.

• Journal of Environmental Health Sciences
• /
• v.19 no.3
• /
• pp.36-40
• /
• 1993

The objective of this research was to retrofit an on-site sewage treatment system suitable to current situation of Korea to reduce the pollution loading and preserve the invaluable water resources. Operation at the F/M ratio of 0.1 kg. BOD/kg MLSS day showed 87.1% BOD removal efficiency and 84.5% COD removal efficiency, and its effluent concentration was 6.4 mg/l as BOD and 21.7 mg/l as COD. Average removal of total nitrogen showed high removal efficiency of 80%.

• Journal of Electrical Engineering and Technology
• /
• v.4 no.4
• /
• pp.515-520
• /
• 2009

According to the operating characteristics of pump applications, they should exhibit high efficiency and energy saving capabilities throughout the whole operating process. A novel efficiency optimization control strategy is presented here to meet the high efficiency demand of a variable speed Permanent Magnet Synchronous Motor (PMSM). The core of this strategy is the excellent integration of mended maximum torque to the current control algorithm, based on the losses model during the dynamic and the grade search method with changed step by fuzzy logic during the steady. The performance experiments for the control system of a variable speed high efficiency PMSM have been completed. The test results verified that the system can reliably operate with a different control strategy during dynamic and steady operation, and the system exhibits better performance when using the efficiency-optimization control.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.18 no.1
• /
• pp.9-17
• /
• 2023

This paper relates to the development of a device for measuring the efficiency of a solar panel based on a variable constant current, and proposed a standard for reuse of the solar panel. By applying a variable constant current circuit to a solar panel efficiency measuring device, it was easy to apply a maximum power point tracking (MPPT) algorithm. In addition, a load dispersion method was applied to measure the efficiency of a high-capacity solar panel. and it is possible to solve a problematic thermal runaway during a MOSFET parallel operation by applying the load dispersion method. As a result of the experiment, the solar panel efficiency measuring device was able to accommodate a large solar panel of 350W, which is the maximum measurement goal. In this paper, the validity was confirmed through the 310W solar panel efficiency measurement experiment collected after removal.