• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.317-320
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• 2001

Sweet com seeds deteriorate faster due to low starch content than field com seeds when stored for a long tenn. This study had been conducted to observe the seed deterioration of four different sweet corns in a long tenn storage conditions in room temperature. Four kinds of sweet com genes (sh2, bt, su, and se) were harvested from 15 days to 50 days after silking with 5-day intervals. These seeds were stored in the room temperature and tested for germination percentages from 3 months to 18 months period with 3-month interval. su seeds germinated better than other types of gene. Hybrid Mecca which is sh2 gene germinated better when stored for 3 months to 18 months. For all genes, mean regression equations in relation to storage periods showed linear responses. For regression equation, the slope of sh2 gene was lower than that of su gene. The highest slope value was observed in bt gene showing faster deterioration rate. The rate at which seed deteriorates seems to be affected by the date at which it was harvested. The seeds that were harvested at the optimum time deteriorated more slowly than those which were not.

• Journal of Convergence Society for SMB
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• v.4 no.4
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• pp.13-18
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• 2014

The usage rate of user due to advances in smartphone development is higher than the usage rate to use a PC. However, smartphone usage popularized research to protect sensitive information, such as smart phone users personal information, financial information is a small state. In this paper, we analyzed the various vulnerabilities in smartphone studies to date have been looking into the corresponding port smart consumer dispute resolution methods and criteria for smartphone security attack methods and analysis. In particular, the threat of such a network, malware, Peep attack of the security threats arising from the smartphone they can avoid or mitigate threats to minimize the smartphone security damage is done to the disclosure of personal information, such as direct damage or financial loss the analysis of that method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.1 s.116
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• pp.90-95
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• 2007

Chaotic OOK(On-Off Keying) modulation method can be used in LDR(Low Data Rate) UWB systems. The chaotic generator in one of the most important circuit in this system. The traditional chaotic generator circuits using analog feed back technique have low yield characteristic due to the process variation. A novel quasi-chaotic signal generator using digital PN-sequence in proposed in this paper and verified in 0.18um CMOS teleology.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.34 no.1
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• pp.1-7
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• 2024

Objectives: The study was performed to investigate characteristics of hazardous factors regarding chemical(liquid lime) tank dredging workers by case survey. Methods: Field data such as working condition, MSDS and respirators applied to chemical tank dredging work were analyzed and the work environmental factors of noise and indoor air quality were measured to compare existing data with actual work situations. Results: No health hazards to workers due to working conditions were confirmed during dredging work inside the chemical storage tank. All air quality measurement data during dredging work satisfied the management standards, and there were no by-products. During dredging work, there was a significant change in noise depending on the type of work, but considering the noise reduction rate(NRR) of the earplugs worn by workers, there was no actual health hazard due to noise exposure. Conclusions: A fit test for respirator and the expiration date of the safety helmet should be observed to ensure an appropriate level of safety and health for dredging workers in the chemical storage tank.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.252-258
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• 2020

The aim of this study was to investigate the effects of timing of collecting date and concentration of IBA and NAA, in order to enhance initial activity and seedling quality of domestic strawberry. Strawberry cuttings were separately taken twice, in June 7 and in July 5, and IBA and NAA were treated with the concentrations of 0.025, 0.05 and 0.1% at cutting date, respectively. The seedlings were evaluated for the percentage of survival during 18 days at 6 times after tunnel cultivation. The NAA treatment was inappropriate for strawberry cutting due to the high rate of seedling mortality, regardless of the collecting date. The vitality of the seedlings was highest at IBA 0.1% in June collecting and at IBA 0.05% in July collecting. The seedlings from June collecting had a higher quantum yield at IBA 0.1% and the seedlings from July collecting at IBA 0.05%. Therefore, IBA could be more effectively applied than NAA to promote the vitality and quality with the appropriate concentration of 0.1% at June collecting and 0.05% at July collecting, respectively.

• Journal of Periodontal and Implant Science
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• v.38 no.2
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• pp.225-230
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• 2008

Purpose: Many clinical studies have reported that higher success rates are achieved with teeth that have immature roots than other autotransplanted teeth that have more immature root. However, based on date published recently, the success rate of autotransplantation of teeth with complete root formation was higher. The purpose of this study was to examine the long term(2 to 6 years follow-up) success rate of autotransplantation of third molar with complete root formation and to discuss some conditions and prerequisites for success. Materials and Methods: 26 sites of 24 patients aged 26 to 55 (mean age 40.8) were autotransplanted with third molars with complete root formation. These cases were followed for 2 to 6 years after surgery. The success criteria included (1) no discomfort during functioning (2) absence of progressive root resorption and alveolar bone resorption. Result: Of 26 teeth 5 teeth were failed, therefore success rate is 81%(21/26 teeth). The results suggested that higher success rate is acquired from (1) extraction socket due to dental caries (2) mandibular recipient site (3) patient younger than 40 years old. Autotransplantation of third molar to replace molars with advanced periodontal disease also showed considerably high success rate(84%). Conclusion: With appropriate case selection, autotransplantation of third molar with complete root formation remains a viable alternative for replacing a missing molar tooth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.11
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• pp.1-9
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• 1972

For a measure against late transplanting, this experiment was conducted to investigate a reasonable seeding rate in nursery bed and a proper nursery size. The treatments applied to this experiment are as follows a) seeding rates: 0.2ι, 0.4ι and 0.6ι per 3.3$m^2$ b) nursery sizes. for 10a-field area: 39.6$m^2$, 49.5$m^2$ and 59.4$m^2$ c) transplanting dates: June 5, June 25 and July 15. The seeding date was April 26 and planting density was determined by the number of sound seedlings based on the combination of seeding rate and nursery size. The results may be summarized as follows: 1. In seedlings both increased nursery period and decreased seeding rate showed a remarkable-increase in plant height, number of leaves, dry matter weight and the ratio of dry weight to plant height. But their number of tillers and live leaves did not show such tendency. 2. Delayed transplanting date shortened culm length and panicle length as well as number of days from transplating to heading and it also delayed heading date. On the other hand the transplanting of 80-day seedlings resulted in premature heading. 3. As a result late transplanting reduced number of spikelets per panicle, maturing rate and 1000-grain weight. In the last analysis it linearly reduced grain yield. The decreasing rate of yield by late transplanting was 15.6% in June 25 plot and 41. 3% in July 15 plot, compared with the yield in June 5 plot. Such a remarkable decrease in yield of the extremely late transplanted plot was mainly due to markedly decreasing number of spikelets per panicle and 1000-grain weight. 4. Both increased seeding rate and nursery size gave a rise in number of tillers per unit area as well as number of transplanting hills but gave a fall in culm length and panicle length. 5. Accordingly, though thick seeded - dense planted plot increased number of panicles per unit area, decrease in number of spikelets per panicle and 1000-grain weight made no differences in yield between thick seeded - dense planted plot and thin seeded - sparse planted one. However, the yield in the thick seeded - dense planted plot transplanted on July 15 was reduced owing to the remarkable decrease in maturing rate and 1000-grain weight. 6. We came to the conclusion that as a measure against the extremely late transplanting the suitable seeding rate was 0.4ι per 3.3$m^2$ and the proper nursery size was 59.4$m^2$ for 10a-field area.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.355-363
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• 2018

This study was conducted to investigate suitable rice cultivars for various rice based cropping systems in a paddy field in the Yeongnam plain area. Thirteen rice cultivars (5 early, 3 medium and 5 mid-late maturing cultivars) and three transplanting dates (June 5, June 25 and July 5) were evaluated in this study. The mid-late and early maturing cultivars for the July 5 and June 25 transplanting headed before August 30 which is the safe heading date in the Yeongnam plain area, ranging from Aug. 26 - 28 and Aug. 18 - 23, respectively. The safe harvest time of rice for double and triple cropping systems should be before the middle of October for the cultivation of the succeeding winter crops. The rice yield was the highest for the June 5 transplanting regardless of the rice cultivars, and it gradually decreased as the transplanting date was delayed from June 5 to July 5 due to a decrease in the spikelet numbers per panicle number and in the ripened grain rate. In contrast, the other yield parameters that include the panicle number per $m^2$, the 1,000-brown rice weight, and the ripened grain ratio were not significantly affected. The result indicates that based on the milled rice, heading time and harvest time, a medium maturing cultivar (Haiami and Samdeog) would be applicable to a winter barley/wheat, garlic/onion-summer rice double cropping, while a mid-late cultivar (Saeilmi, Saenuri and Hyunpoom) would be suitable for a spring potato/waxy corn-summer rice double cropping in the Yeongnam plain area. On the other hand, an early maturing cultivar (Unkwang, Jokwang and Haedamssal) would be preferable for a triple cropping because of the short growth period of rice.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.59-66
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• 2006

This research is based on the information compiled on the occurrence of maritime casualties onboard ships registered under Central American Region (CAR) flag States. Due to nonexistence of writing reports in anyone of the countries that are integrating this Region, the information was compiled by the author through personal communication with the people involved in the casualties. The information was compiled by typing up the text and digitizing on the computer for the respective data base. For each casualty occurred, the following information was compiled, date and type of the casualty, position of the ship at the time of the casualty, dimension of the ship, number of people affected by the casualty, and cause and consequences of the casualty. Based on the number of people affected (death and disappear) by the casualties occurred was calculated the mortality rate by 100,000 persons and then compared with the Japanese mortality rate. Furthermore were analyzed the CAR maritime authorities competences and then were compared to that the Japanese counter part. In addition, the implementation rate of the International Maritime Organization (IMO) and International Labor Organization (ILO) conventions ratified by the CAR countries were analyzed. The objective of this research was to compiled and analyze the occurrences of maritime casualties happened on board the ships registered under the CAR Flag States, in order to determine the causes of these accidents. The results of the analysis enable us to better understand of the maritime safety situation of the ships that are registered under the CAR flag States. In order to reduce the occurrence of maritime casualties are proposed a series of measures based on the differences found then the comparison between CAR and Japan. Based on the results of this research, is possible to conclude that the inaccessibility of atmospheric information and the lack of safety measures onboard has been the main cause of the maritime casualties happened in the Pacific side of the CAR.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.36-41
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• 2013

In this paper time series wave data are simulated using wave spectrum with random phases of the wave signal. The simulated wave signals are used to study the effect of the sampling rate on the ocean wave characteristics. Effect of sampling rate on wave data which include extreme wave such as freak waves are examined and various wave characteristics including abnormality index (AI), kurtosis of wave profile and maximum wave height are examined. Various wave heights are decreased as the sampling rate decreases. The zero-th moment of the wave spectrum does not affect much on the sampling rate but the second moment are greately affected on the sampling rate. The error due to the sampling rate is decreases as the wave period increases. The error in significant wave height based on the wave spectrum $H_s$ is smaller than that on the time domain method $H_{1/3}$. AI index and kurtosis of wave profile do not deviate much from the exact date as long as the sampling rate is greater than 1 Hz. Ocean wave measurement with the sampling frequency higher than 1 Hz will result the error less than 5% in estimating the height of extreme waves.