• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.400-403
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• 2011

This experiment was carried out to determine the effect of mechanization on lavor-saving in sweetpotato cultivation. The field experiment was conducted from 2005 to 2006 in Mokpo Experiment Station of the National Institute of Crop Science. In order to determine the efficiency of mechanical harvesting, different harvesting methods were compared. Mechanical harvesting method was done as follows: cutting of vines by machine, removal of plastic film mulching, and harvesting by two-row and one-row harvesting system. The result showed harvesting labor was decreased by 66.6% in two-row harvesting. The ratio of damaged sweetpotato by mechanical harvesting decreased by 49.4% in two-row and 38.4% in one-row harvesting compared to conventional method. The total labor cost was saved by 48.2% - 70.4% using mechanical method. In addition, the total income also increased by ca. 62.9% - 81.2%. Thus, it was concluded that mechanical harvesting is more efficient and economical method than conventional one.

• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.47-52
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• 2015

The transient phenomenon of self-powered energy-harvesting is assessed using a bond-graph method. The bond-graph is an energy-based approach to describing physical-dynamic systems. It shows power flow graphically, which helps us understand the behavior of complicated systems in simple terms. Because energy-harvesting involves conversion of power in mechanical form to the electrical one, the bond-graph is a good tool to analyze this power flow. Although the bond-graph method can be used to calculate the dynamics of combining mechanical and electrical systems simultaneously, it has not been used for harvesting analysis. We demonstrate the usability and versatility of bond-graph for not only steady analysis but also transient analysis of harvesting.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.10-13
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• 2015

This paper proposed a novel user's information feedback algorithm for improving network energy harvesting rate. The proposed algorithm is focused on determining energy harvesting users comparing increasing ratio of the amount of harvesting energy versus emitted energy and network threshold ${\alpha}$, which is critical harvesting parameter. Using this method, we can increase the rate of network energy harvesting preventing emitted energy from wasting inefficiently. The result of experiment in this paper shows that user's information feedback algorithm makes network energy harvesting rate more efficiently when it uses threshold ${\alpha}=15%$ to determine energy harvesting users.

• Journal of Mushroom
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• v.2 no.1
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• pp.42-43
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• 2004

Labor required for managing and harvesting the oyster mushroom bed was evaluated. Although vinyl mulching cultivation method needs more hours for spawning, it saves more than 50% of labor for harvesting and managing of the mushroom bed. Harvesting hour of 1st-3rd flush in vinyl mulching method was 48~50% for Plerutus ostreatus and 36~41% for P. sajor-caju. Labor for bed management after harvesting in vinyl mulching method was also 38~50% for P. ostreatus compared to conventional method, and 20~35% for P. sajor-caju. Vinyl mulching is believed to be a very efficient method for saving labor in oyster mushroom cultivation.

• Journal of Biosystems Engineering
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• v.27 no.6
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• pp.513-520
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• 2002

A 5-row walking garlic harvester with pulling mechanism was developed in the study, based upon a kinematical analysis and related preliminary field tests on the conventional garlic harvesting method. The harvesting efficiency of the developed harvester was more than 98% in the garlic field irrigated before harvesting, 80-85% in the field without irrigation. The harvesting performance of the harvester was 660∼825㎡/hr at the forward speed of harvester of 0.3m/s in the irrigated field before garlic harvesting. For proper garlic drying and collection, the harvester discharged the harvested garlic on the ground uniformly at the angles of 135。∼150。 to its forward direction with the garlic bulb's placing toward the harvester. In the field tests, it was recommended that the forward speed of the harvester be approximately less than 0.2m/s, and that the spacing of planting garlic seeds should be standardized in the future fur increasing its harvesting efficiency.

• Journal of Embryo Transfer
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• v.23 no.2
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• pp.127-131
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• 2008

Bone marrow (BM) cell harvesting is a crucial element in the isolation of mesenchymal stem cells (MSCs). A simple method for harvesting cat BM cells is described. The results show that a large number of BM cells can rapidly be harvested from the cat by this simple procedure. MSCs prepared by density-gradient method were spindle-shaped morphology with bipolar or polygonal cell bodies and strongly positive for CD9 and CD44 and negative for CD18 and CD45-like. They were capable of differentiation to adipocytic and osteocytic phenotypes when exposed to appropriate induction media. The advantages of this method are its rapidity, simplicity, low invasiveness, and low donor attrition and good outcome.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.1
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• pp.18-23
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• 2023

A smart sensor is the key element to implement IoT (Internet of Things) service, as a terminal equipment. This paper investigated the design method of a power supply using energy harvesting technique for a smart sensor. the performance of a power supply using a solar cell and a piezoelectric transducer as a energy harvesting device was verified and the method to optimize a power supply was analyzed depending on the operating condition of a smart sensor. Also the method to increase a battery life cycle as a auxiliary power supply was proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.149-152
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• 2017

This paper investigated the method for the output of power management IC (PMIC) for BLE beacon with energy harvesting device to be maintained constantly. The capacitor was used to store the energy supplied from energy harvesting device such as solar module and the capacitance was estimated to the optimum value according to the interval for the BLE beacon to send advertising signal.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.2
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• pp.3772-3777
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• 1975

This paper reports on the analysis of the distributions of probable days being good for mechanical rice harvesting and the method of determining the capacity of rice harvesting machinery for the given harvesting duration. In the analysis of the probability distribution of days being good for rice harvesting, the daily rainfalls above which mechanical field work may be impracticable were specified and their frequency of occurances was analyzed by using the weather records during past twenty-one years measured at five different locations. The conclusions being drawn from the analysis are as follows: 1. The distributions of probable workable days in different region and harvesting duration are very distinct and are different to set a uniform trend (refer to Fig. 1-4). 2. The occurance of probable days being good for mechanical field work under 66% confidence level are quite variable by region and by ten-day period. The analysis indicates that the probable workable days may range from 7.5 to 8.5 days of 10-day span within optimum harvesting duration (refer to Table 1). 3. Based on the probability distributions analyzed, the optimun capacities of harvesting machinery required for different harvesting areas and harvesting start-date were estimated as a function of operating duration (refer to Fig. 5 and Table 2)

• Smart Structures and Systems
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• v.19 no.4
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• pp.403-413
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• 2017

The present article encompasses a nonlinear finite element (FE) and genetic algorithm (GA) based optimal vibration energy harvesting from nonprismatic piezo-laminated cantilever beams. Three cases of cross section profiles (such as linear, parabolic and cubic) are modelled to analyse the geometric nonlinear effects on the output responses such as displacement, voltage, and power. The simultaneous effects of taper ratios (such as breadth and height taper) on the output power are also studied. The FE based nonlinear dynamic equation of motion has been solved by an implicit integration method (i.e., Newmark method in conjunction with the Newton-Raphson method). Besides this, a real coded GA based constrained optimization scheme has also been proposed to determine the best set of design variables for optimal harvesting of power within the safe limits of beam stress and PZT breakdown voltage.