• Journal of Biosystems Engineering
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• 제43권4호
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• pp.379-385
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• 2018

Purpose: Postharvest handling of onions (harvesting, cleaning, grading, cooling, storing, and transport) should be performed continually to reduce costs and improve quality. The purpose of this study is to a) determine the design parameters and operating conditions of anion auto-dumping that constitutes a key component of the postharvest bulk handling machinery system, and b) to perform a performance test with the auto-dump prototype system. Methods: Kinematic analyses and computer simulations of the auto-dump mechanism were applied to analyze the operating conditions and design parameters. Results: The optimum working condition for the auto-dump was determined from kinetic analyses. In addition, the interaction between the velocity of the hydraulic cylinder and the angular velocity of the auto-dump were analyzed in order to control the bulk handling machinery system. The acting forces and optimum operating conditions of the hydraulic cylinder were determined by analyzing the forces related to the mass of inertia of the auto-dump assembly during rotation. The method of controlling the feeding rate of onions in terms of the uniformity of the stacking pattern and the control of the entire system was better than the two-stage method of controlling the rotational speed of the auto-dump. Based on the performance test with the prototype for the auto-dump, the stacking pattern and rigidity of the system were analyzed. Conclusions: These results would be of great importance in the postharvest bulk handling machinery system for onions.

• Journal of Information Processing Systems
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• 제6권3호
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• pp.413-434
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• 2010

Wireless sensor networks are usually characterized by dense deployment of energy constrained nodes. Due to the usage of a large number of sensor nodes in uncontrolled hostile or harsh environments, node failure is a common event in these systems. Another common reason for node failure is the exhaustion of their energy resources and node inactivation. Such failures can have adverse effects on the quality of the real-time services in Wireless Sensor Networks (WSNs). To avoid such degradations, it is necessary that the failures be recovered in a proper manner to sustain network operation. In this paper we present a dynamic Energy efficient Real-Time Job Allocation (ERTJA) algorithm for handling node failures in a cluster of sensor nodes with the consideration of communication energy and time overheads besides the nodes' characteristics. ERTJA relies on the computation power of cluster members for handling a node failure. It also tries to minimize the energy consumption of the cluster by minimum activation of the sleeping nodes. The resulting system can then guarantee the Quality of Service (QoS) of the cluster application. Further, when the number of sleeping nodes is limited, the proposed algorithm uses the idle times of the active nodes to engage a graceful QoS degradation in the cluster. Simulation results show significant performance improvements of ERTJA in terms of the energy conservation and the probability of meeting deadlines compared with the other studied algorithms.

• 한국식품영양과학회지
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• 제30권1호
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• pp.56-63
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• 2001

This study investigated the quality characteristics of yeast breads with addition of hot air-dried yam powder (HDYP) and freeze-dried yam powder (FDYP), using several physical and sensory examinations. Breads were made of imported wheat flour (IWF) or Korean wheat flour (KWF). HDPY and FDYP were added to the bread formula at three levels of 3, 5, and 7%. The addition of yam powders required an increase of water absorption. As the addition of HDYP/FDYP increased, IWF dough stickiness increased and thus handling property became inferior to the control. Especially, handling property of KWF bread dough containing FDYP was most poor among the dough samples. With HDYP/FDYP, final volumes of bread made from IWF were similar to the control when 3~5% HDYPs were added whereas loaf volumes decreased significantly as the amount of added FDYP increased, indicating volume depressing effect. In bread scoring, texture scores increased when yam powders were added that hardness, chewiness, cohesiveness and guminess of KWF bread increased as the amounts of yam powders increased. The "L" value of IWF bread crumb decreased with the addition of yam powders. From sensory evaluation using acceptability scores, the results gave us that appearance, grain, texture, flavor, taste and overall acceptability of KWF bread could be more improved with the addition of yam powders than those of IWF bread.IWF bread.

• 한국통신학회논문지
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• 제23권9A호
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• pp.2325-2332
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• 1998

In this paper, the quality scalable coding of selected region is presented. If a region is semantically more important than the others, it is appropriate that the image compression shcem is capable of handling the regional semantic difference because the information loss of the region of interest is more severe. We propose the quality scalable coding with its model by interoducing the quality scale parameter. It is more extended and generalized image compression philosophy than te conventional coding. As an implementation of the proposed quality scalable coding, H.263 based scheme is presented. This scheme can control the temporal and spatial quality efficiently, and improve the reconstructed image quality of the region of interest.

• 대한지역사회영양학회지
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• 제10권6호
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• pp.943-951
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• 2005

The purposes of this study were to analyze the gap between foodservice personnel and inpatients, to urge foodservice providers to reconsider by identifying the problems in service delivery for customer satisfaction, and to deduce the priority for foodservice quality improvement. The results of this study can be summarized as follows : the average perception score of personnel (4.32 out of 5) was higher than that of customers (3.90). In particular, the customers' perceptions of 17 attributes, which included 'removal service of tray by foodservice personnel', 'nutrition and health-related information service', 'handling inpatient's complaint ASAP', 'delicious meals' and 'salty enough meals' and so on, was significantly lower than personnel's. Both service providers and customers perceived that 'personnel attitude' was the highest and 'meal quality' was the lowest among the 4 factors, but there was significant difference on 'meal quality'(p < .001), 'customer reception' (p < .001) and 'personnel attitude' (p < .05) between the two groups. As a results of quadrant analysis, 'removal service of tray by foodservice personnel', 'handling inpatient's complaints ASAP' and 'meal service according to doctor's orders were categorized into Quadrant A with meaning of high personnel's perceptions and low customers'. Therefore service providers have to perceive the gap between the two viewpoints and grant priority to these attributes in improving foodservice qualify. (Korean J Community Nutrition 10(6) $943\∼951$, 2005)

• 한국항만경제학회지
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• 제26권3호
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• pp.198-220
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• 2010

본고에서는 컨테이너 선석 당 적정처리능력 40만 TEU로 설정하고 컨테이너항만을 40만 TEU에 맞는 선석 개수로 개발하는 현재의 우리나라 항만기본계획의 문제점을 분석하였다. 선사가 요구하는 고 생산성의 터미널을 건설하여 선사의 물동량을 유치하고, 이를 통해 그 항만 배후지에서 고 부가가치 생산활동을 가능케 하려면, 40만 TEU 표준하역능력 같은 항만개발 제약요인을 두어서는 초대형선 부두 이용자의 요구를 충족시키기 어려울 것으로 판단된다. 10,000 TEU 이상 초대형 컨테이너선 기항 시 선사가 요구하는 서비스 수준은 항만대기시간과 항만 내 체류시간으로 나누어 설문조사를 실시한 결과 초대형 컨테이너선에 대해서 대기가 발생하지 않는 수준의 서비스를 제공해야 함을 확인할 수 있었다. 그리고 10,000 TEU급 이상 초대형 컨테이너선 기항시 선사가 요구하는 총 재항시간은 대부분24시간 이었다. 이를 바탕으로 12,000 TEU 급 초대형선이 24시간 이내에 서비스를 완료할 수 있는 항만의 하역능력을 산정해본 결과 초대형선 선석 400미터 2선석, 피더선 250미터 2선석의 1,400m 컨테이너 터미널의 연간 요구 처리능력은 약 300만 TEU가 되었다. 이를 실현할 수 있도록 하는 시뮬레이션 분석을 한 결과 주 선석 2개(900미터)와 피더선석 2개(500미터)의 1400미터 선석에서 300만 TEU를 처리해도 선석점유율, 선박대기시간이나, 서비스 면에서 기존의 항만보다 오히려 우수한 결과를 보이고 있다. 이를 장비가격으로만 비교할 때 기존터미널에 비해 700억원 정도(28%)를 더 투자하면 연간 처리능력이 160만 TEU에서 300만 TEU로 88%이상 증가할 수 있음을 보여준다. 따라서 전국항만 기본계획에서는 기존의 선석 수 개발방향에서, 항별로 미래 일정기간 동안 건설 필요 처리능력 한도를 실제 건설되는 처리능력의 누계를 관리해 나가는 정책으로 전환해야 할 것이다.

• 기술사
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• 제16권1호
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• pp.71-77
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• 1983

Meat itself contains all the essential nutrients for the organisms, because it is high in moisture, rich in nitrogenous, Plentifully supplied with minerals and accessory growth factors, usually has come fermantable carbohydrates and is at a faverable PH for most microorganisms. So, microorganisn can grow and multiply rapidly well in it and caused spoilage of meat and their Product. Therefore, storage and handling of meat must be Strictly controlled on contamination and growth of organism by a low temperature, among the low temperature control, chilling control of meat is one of the best method as good retention for meat quality.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.430-433
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• 2003

In this paper, we propose the method of voice packet transformation for the improvement of voice quality in embedded VoIP system terminals. For this purpose, it was analyzed about the RTP header in the voice packet receiving side and designed about the handling method of voice packets by using jitter buffer. Through this analyzed and designed results, by implementing the voice packet transformation method and testing on the self-product VoIP system, we reached that a conclusion is satisfied with performance of VoIP services.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1164-1165
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• 2005

• 한국입자에어로졸학회지
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• 제13권1호
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• pp.11-16
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• 2017

Indoor air quality is of increasing concern because it is closely related human health. An air handling unit (AHU) can be used to control the indoor air quality related to particulate matters and $CO_2$ as well as air conditioning such as temperature and humidity of indoor air. An electrostatic precipitator has a high collection efficiency and low pressure drop, however, ozone can possibly generate from its chargers, which is one of drawbacks to apply it for indoor air control. Here we compared four charging electrodes such as a $50{\mu}m$ tungsten wire, a $100{\mu}m$ tungsten wire, a $16{\mu}m$-thickness Al foil and a carbon fabric comprised of $5-10{\mu}m$ fibers. The carbon fabric electrode showed a superior particle collection efficiency and a lower ozone generation at a given power consumption compared to tungsten wires of 50, $100{\mu}m$ and an Al foil electrode. This low ozone generating, micro-sized electrode can be applied to the electrostatic precipitator in AHU for indoor air control.