• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.620-629
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• 2019

To examine the possibility of ear mushroom (EM) as a source of natural vitamin D, the UVB (ultraviolet B) was treated according to sample drying status, drying methods before UVB treatment and harvest time. And then, vitamin D₂ and ergosterol contents were investigated. According to the sample drying status, the vitamin D₂ contents of fresh and freeze-dried EM (whole) increased to 4,634.4~4,780.9 ㎍/100 g D.W. (dry weight) under UVB dose 52.5~70.0 kJ/㎡ and above 18,693.1 ㎍/100 g D.W. under above 105 kJ/㎡, respectively. By drying methods before UVB treatment, vitamin D₂ contents of EM powder (below 500 ㎛) that dried in the vinyl house and freeze-dryer increased to 4,886.2~5,132.9 ㎍/100 g D.W. under above 105 kJ/㎡ and 17,103.7 ㎍/100 g D.W. under 70 kJ/㎡, respectively. Ergosterol content decreased with increasing UVB dose in all experiments. According to the harvest time, vitamin D₂ content under UVB dose 210 kJ/㎡ showed marked difference and in order of June, July, August, October and April. As for the results, the optimum harvest time, drying method before UVB treatment, sample size, UVB dose for the EM contained high vitamin D₂ content were June, freeze-drying, whole, and 105 kJ/㎡, respectively.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.220-228
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• 2018

This study investigated the chemical composition of burdock (Arctium lappa L.) leaves essential oil, and the quantitative changes of the major terpene compounds according to the specific harvesting season. The essential oils obtained by the hydrodistillation extraction (HDE) method from the aerial parts of the burdock leaves were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). The essential oil composition of this plant was characterized by the higher content of phytol and 6,10,14-trimethyl-2-pentadecanone. Seventy seven (98.28%) volatile flavor compounds were identified in the essential oil from the burdock leaves harvested during the spring season of 2012, and phytol (33.47%) and 6,10,14-trimethyl-2-pentadecanone (32.47%) were the most abundant compounds. Eighty eight (99.08%) compounds were identified in the essential oil from the leaves harvested during the autumn season of 2012, and in this case, phytol (37.35%) and 6,10,14-trimethyl-2-pentadecanone (34.67%) were also the most abundant compounds. These two volatile components were confirmed as the major oil components of the burdock leaves during the time of any harvest. The ratio between the two components contained in the burdock essential oils did not differ significantly by harvesting season. But overall, the essential oil harvested during the spring season contained 65.94% of the two major components, while for the essential oil harvested during the autumn season, the total amount of these two major components was 72.02%. While the main ingredients of the essential oils were found to be unchanged from one harvest time to the next, it was found to differ in content. For the burdock leaves, the quality index of the volatile constituents according to the harvest time would be more useful for utilizing the total quantity other than the proportion between phytol and 6,10,4-trimethyl-2-pentadecone.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.299-303
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• 1992

Methods for harvesting and storage of rice were also originally introduced from the ancient China like other practices of agricultural techniques. Thus, optimum time or rice harvesting was adopted by appropriate draining to prevent the losses, and efficient tools were utilized for harvesting and manufacturing. In addition, our unique and original techniques for rice storage were learned and handed down, which prevented winds and rains, and allowed good ventilation. In the 15th and 16th centuries, treatment of smartweed extracts as emphasized to prevent insect damage for stored barley and rice cutting immediately at harvest was encouraged to prevent shattering of rice grains. In the 18th and 19th centuries, means for prevention of damages by water, insects and rats when grains stored in the field were suggested. Also, studies for ecology of various rice cultivars and storage techniques for a long period of time were necessarily emphasized to assume the optimum time of harvest regionally and to cooperatively work timely.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.64-67
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• 1980

Field experiments were conducted to determine the optimum harvesting time and to evaluate the effect of Diquat spray in late seeded sesame, cultivar 'Suweon 9'. Sesame seed yield reached a plateau from Sept. 18 harvest when seed number was maximum. Thousand seed wt. increased to Sept. 29 harvest. As harvesting was delayed moisture content of capsule decreased and capsule dehiscence increased. Capsule dehiscence did not start until its moisture content dropped below 70%. Optimum harvesting might begin from the time which moisture content of capsule dropped below 70%, leaf senescence reached upper node, and 50% of capsules lost green. About 5% increase in seed weight after defoliation was estimated to be translocation from capsule wall. Diquat spray with 0.3% and 0.5% (v/v) solution of commercial Reglone (20%in A.I.) decreased rapidly capsule moisture content and promoted seed shattering. Dehiscence in 90% capsules was noted at seven days after Diquat spray. Diquat spray as a harvest aid could accelerate sesame desiccation up to 2 wks from normal field condition.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.04a
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• pp.168-169
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• 2005

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.213-219
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• 2018

This study was performed to determine the optimal time of harvest for ramie leaves with the two varieties (Seocheon Seobang and Seoncheon Baekpi) by comparison of physiological activity and physicochemical characteristics. The crude protein, minerals, ascorbic acid, folate, chlorophyll, ACE inhibitory activity and AChE inhibitory activity were determined. The amount of crude protein in ramie leaf, which was collected in Seocheon-gun, Chungcheongnam-do, grew up steadily from early May to September. The content of calcium in was higher in Baekpi than in Seobang. Seobang displayed its highest value of 3,569.90 mg% in September, while Baekpi displayed its highest value of 3,163.84 mg% in October. Although, folate and vitamin C contents in the two varieties were slightly different, they were higher as the growth date grew in October. The highest value of chlorophyll content was observed in October, which was later in the vegetative state. ACE inhibitory activity and AChE inhibitory activity appeared to be higher in Baekpi than in Seobang. Between June and August, ACE inhibitory activity was highest in Baekpi variety.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.533-543
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• 2015

This study investigated the chemical composition of Artemisia princeps var. orientalis (Pampan) Hara (ssuk in Korea) essential oil and the quantitative changes of major terpene compounds according to the time of harvest. The essential oils obtained by hydrodistillation extraction from the aerial parts of ssuk were analyzed by GC and GC-MS. The essential oil composition of ssuk was characterized by higher contents of mono- and sesqui- terpene compounds. Ninety-nine volatile flavor compounds were identified in the essential oil from ssuk harvested in 2010, with camphor (11.9%), ${\beta}-caryophyllene$ (9.11%), dehydrocarveol (8.51%), and borneol (7.72%) being the most abundant compounds. Eighty-three compounds were identified in the essential oil from the plant harvested in 2011, with borneol (12.36%), caryophyllene oxide (12.29%), ${\beta}-caryophyllene$ (10.24%), camphor (9.13%), and thujone (8.4%) being the most abundant compounds. Eighty-four compounds were identified in the essential oil from the plant harvested in 2012, with ${\beta}-caryophyllene$ (20.25%), caryophyllene oxide (14.63%), and thujone (11.55%) being the major compounds. Eighty-nine compounds were identified in the essential oil from the plant harvested in 2013, with thujone (23.11%), alloaromadendrene oxide (12.3%), and ${\beta}-caryophyllene$ (11.48%) being the most abundant compounds. Thujone and aromadendrene oxide contents increased significantly from 2010 to 2013, while camphor and dehydrocarveol contents decreased significantly during those 4 years. The quantitative changes in these 4 compounds according to the time of harvest can served as a quality index for ssuk essential oil. The ecological responses to recent climate changes may be reflected in the chemical components of natural plant essential oils.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.8
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• pp.3542-3566
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• 2018

In this paper, we investigate a buffer-aided wireless powered cooperative communication network (WPCCN), in which the source and relay harvest the energy from a dedicated power beacon via wireless energy transfer, then the source transmits the data to the destination through the relay. Both the source and relay are equipped with an energy buffer to store the harvested energy in the energy transfer stage. In addition, the relay is equipped with a data buffer and can temporarily store the received information. Considering the buffer-aided WPCCN, we propose two buffer-aided relaying protocols, which named as the buffer-aided harvest-then-transmit (HtT) protocol and the buffer-aided joint mode selection and power allocation (JMSPA) protocol, respectively. For the buffer-aided HtT protocol, the time-averaged achievable rate is obtained in closed form. For the buffer-aided JMSPA protocol, the optimal adaptive mode selection scheme and power allocation scheme, which jointly maximize the time-averaged throughput of system, are obtained by employing the Lyapunov optimization theory. Furthermore, we drive the theoretical bounds on the time-averaged achievable rate and time-averaged delay, then present the throughput-delay tradeoff achieved by the joint JMSPA protocol. Simulation results validate the throughput performance gain of the proposed buffer-aided relaying protocols and verify the theoretical analysis.

• Korean Journal of Plant Resources
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• v.32 no.6
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• pp.683-688
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• 2019

This study was conducted to determine the number of days required to break a plant's dormancy and promote subsequent crop growth in new varieties of Gomchwi through the 4℃ treatment. Three new varieties of Gomchwi namely, 'Sammany', 'Gommany', and 'Damogy' were observed in this study. The rate of leaf emergence of 'Sammany' after 15-day of 4℃ treatment was 100%, while 'Gommany', and 'Damogy' took 20-days and 10-days, respectively to reach to 97.9% rate of leaf emergence. After 10-days of 4℃ treatment, 'Damogy' grew faster than the other varieties. and Harvest time for 'Damogy' was on January 18^th, after 5-days of 4℃ treatment and yield was observed to be the highest at 15-days of 4℃ treatment. 'Sammany' was next with a minimum of 10-days of 4℃ treatment, although 15-days is more preferred for better harvest. 'Gommany' on the other hand, did not grow enough for harvest by January 18^th, and its harvest time was delayed to January 31^st. It needed a minimum of 15-days and preferentially 20-days of 4℃ treatment to grow normally and be ready for harvest. The plant height, leaf length and leaf petiole length appeared to grow better by extending duration of the 4℃ treatment. The number of leaves of 'Sammany' and 'Gommany' varieties was three leaves for the 5-days treatment which may be due to the incomplete breaking of dormancy. Regarding the yield per plant, 'Sammany' yielded 112.3 grams (g) in 15-days treatment, and 'Gommany' yielded 106.5 g in 25-days treatment. In the case of 'Damogy', it yielded 123.5 g and 183 g in the 10-days and 25-days treatment respectively. It is concluded that 'Damogy', 'Sammany' and 'Gommany requires 10, 15, and 20 days of 4℃ treatment to break the plant's dormancy and promote better plant growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.86-91
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• 1987

Changes in the contents of sugars and soluble solids and flavor rate of cooked kernels of three sweet com hybrids (Great Bell, Danok 1, and Golden Cross Bantam) and a super sweet corn hybrid (Crisp Super Sweet 720) were observed from 15 days after silking (DAS) to 27 or 33 DAS in 1985 and 1986 to determine the optimum harvest time. Sucrose content in all hybrids and fructose and glucose contents of Crisp Super Sweet 720 increased from 15 DAS to 21 or 24 DAS and then decreased. However, in the three sweet corn hybrids both fructose and glucose contents were highest at 15 DAS and then continuously decreased with maturity. At harvest time the major sugar component was sucrose and the highest total sugar content of Crisp Super Sweet 720 was 2-3 times higher than that of three sweet corn hybrids. Soluble solids were continuously increased with maturity in three sweet com varieties, but that of Crisp Super Sweet 720 increased up to 24 DAS, maintained the level through 30 DAS and then decreased. At harvest time soluble solids of three sweet com varieties were much higher than that of Crisp Super Sweet 720. The optimum harvest time seems to be about 27 DAS considering flavor rate and marketing conditions although the total sugar content was lower than those of earlier harvests. Soluble solids but not total sugars were positively correlated with the flavor of cooke6 com harvested at different growth stages in the same variety. Total sugars were not correlated with soluble solids or negatively correlated depending on hybrids.