• Title/Summary/Keyword: Fall-applied N

Search Result 59, Processing Time 0.03 seconds

Late Fall Nitrogen Application and Turf Cover for Zoysiagrass (Zoysia japonica) Spring Green-up

  • Oh, Jun-Suk;Lee, Yu-Jin;Lee, Sang-Kook
    • Weed & Turfgrass Science
    • /
    • v.4 no.4
    • /
    • pp.383-389
    • /
    • 2015
  • The use of zoysiagrass (Zoysia japonica Steud.) in the transition zone is limited because of a lack of cold hardiness although zoysiagrass has many advantages compared to other warm-season and cool-season grasses. Late-fall N fertilization is often applied for darker green color of turfgrass in early spring and more extensive root growth without rapid top growth. The objective of the study was to evaluate the effects of late fall N application and turf cover for zoysiagrass spring green-up. Clear polyvinyl chloride (PVC) film was used for turf cover. The amount of N applied were 5 and $10g\;N\;m^{-2}$ for the low and high N rate treatments, respectively. Covered zoysiagrass had greater turfgrass color and quality in early spring than non-covered zoysiagrass. The high N rate had 0.6 to 2.3 greater turfgrass quality than the low N rate on 7 of 9 rating dates. Slow-release N as late fall fertilization is more effective for turfgrass color and quality than fast-release N in spring. Turf cover could reduce the period of yellow zoysiagrass, and the earlier time of spring green-up could be advanced by increasing turfgrass quality and growth of zoysiagrass.

The Effect of 12Weeks Complexed Lower Body Muscle-Strengthening Exercise Program on Fall Risk in Elderly women (여성노인에게 적용한 12주간 복합하지근력 운동프로그램이 낙상위험도에 미치는 영향)

  • Baek, Soon-Gi;Choi, Hye-Jung
    • Journal of Digital Convergence
    • /
    • v.13 no.10
    • /
    • pp.533-539
    • /
    • 2015
  • The purpose of this study was to investigate the effects of 12weeks complexed lower body muscle-strengthening exercise program on fall risk in elderly women. Twenty subjects volunteered to participate who use a welfare center in W city For the study we divided into two groups: exercise group (EC, n=10, mean age:$69.6{\pm}2.2$), comparative group(CG, n=10, mean age:$71.3{\pm}4.6$). In order to investigate the effect of lower body muscle-strengthening program on the degree of risk of fall. It reached a conclusion as follows after having applied BBS (Berg Balance Scale) and OLST (One-Leg Stance Test) to examine the degree of risk of fall. As a result of changes in BBS and OLST, there were significant differences between EG and CG for each test(p<.00). Therefore, it confirmed that the application of complexed lower body muscle-strengthening program to the elderly who have a high risk of fall influences the risk of fall positively.

Preparation and Characterization of Shock Energy Absorber Lanyard used Super Fibers (슈퍼 섬유를 이용한 Shock Energy Absorber Lanyard의 제조 및 특성분석)

  • Cho, Jin Won;Kwon, Sang Jun;Choe, Jong Deok;Kim, Sang Tae;Ji, Byung Chul;Yeum, Jeong Hyun
    • Textile Coloration and Finishing
    • /
    • v.26 no.3
    • /
    • pp.173-180
    • /
    • 2014
  • Fall-arrest system have been widely applied to provide a safe stop during fall incidents for occupational activities. This research object to evaluate the energy capacity of fall arrest shock energy absorber lanyard in relation to the used super fiber. In this work, shock energy absorber lanyard was prepared using high tenacity PET, high tenacity PET/P-aramid and high tenacity PET/UHMWPE, respectively. Dynamic load and static load tests based on the Korea fall protection equipment standard(Korea Occupational Safety & Health Agency standard 2013-13) were conducted. Maximum arrest force by dynamic load test of shock energy absorber showed below 6,000N. Also, static strength by static load test of lanyard and rope remains 15,000N and 22,000N for 1 min.

Optimum Application Amount, Timing, and Frequency of Slurry Composted and Biofiltered Liquid Fertilizer for Zoysia japonica 'Millock'

  • Park, Suejin;Lee, Seung Youn;Ryu, Ju Hyun;Jung, Hyun Hwan;Kim, Ki Sun
    • Horticultural Science & Technology
    • /
    • v.30 no.6
    • /
    • pp.635-641
    • /
    • 2012
  • In Korea, slurry composted and biofiltered (SCB) liquid fertilizer is produced through the composting and biofiltering of animal waste. An appropriate guidelines involving proper treatment of SCB liquid fertilizer on turfgrass should be considered. An experiment was conducted to determine the optimum application amount, timing, and frequency of SCB liquid fertilizer for Zoysia japonica 'Millock'. The SCB liquid fertilizer was applied in low, medium, and high amount (N at 15, 25, and 40 $g{\cdot}m^{-2}$ per year in 2010, and 10, 20, and 40 $g{\cdot}m^{-2}$ per year in 2011, respectively) and treated during the growing season or dormancy period. During the growing season, SCB liquid fertilizer was applied twice or four times. The greatest improvement in turf quality for both years was in SCB plots applied four times with N at 40 $g{\cdot}m^{-2}$ per year during the growing season (SH4). This treatment exhibited turf color retention in the fall, and enhanced clipping yield during the growing and fall seasons. SCB plots with four times during the growing season (SL4, SM4, and SH4) exhibited higher shoot density relative to the same amount of other SCB treatments. Plots treated during the dormancy period also showed a high turf color index during the next growing season in 2011. The results indicate that SCB with high amount up to N at 40 $g{\cdot}m^{-2}$ per year applied four times during the growing season and dormant application produced high turf quality and growth, and could be recommended as an optimum application guide.

Development and Evaluation of Fall Impact Protective Clothing for the Elderly Women (여성 노인을 위한 낙상충격 보호팬츠 개발 및 평가)

  • Park, Jung Hyun;Lee, Jin Suk;Lee, Jeong Ran
    • Fashion & Textile Research Journal
    • /
    • v.20 no.5
    • /
    • pp.569-582
    • /
    • 2018
  • The purpose of this study is to verify the impact protection performance and to evaluate the activity, design, fit, and pad characteristics of the fall impact protection clothing for elderly women. The protective clothing was designed as pants type and underwear type, and an impact protection pad in the form of a tightly connected regular hexagon piece was inserted in the hip and hip joints. The pad was made of two kinds of foam single pad and foam and gel combination pad so that they could be inserted into pants type and underwear type, respectively. The results of the shock absorption performance of the fall impact protective clothing showed that when the impact force of 4601N was applied to the pants type protective clothing, the impact force was reduced by 29% in the foam pad type and 26% in the gel and foam pad type. When the force of 5113N was applied to the underwear type, it decreased by 40% in the foam pad type and by 34% in the gel and foam pad type. As a result of wearing evaluation of subject group, it was found that fit and activity of underwear type was better than that of pants type. Foam pad type was evaluated to be lighter than gel and foam pad type in both the subject and the expert group and the gel and foam pad was evaluated to be more flexible in the expert group.

UNBIASED ESTIMATORS IN THE MULTINOMIAL CASE

  • Park, Choon-Il
    • Communications of the Korean Mathematical Society
    • /
    • v.11 no.4
    • /
    • pp.1187-1192
    • /
    • 1996
  • It is known that an unbiased estimator of f(p) for binomial B(n,p) exists if and only if f is a polynomial of degree at most n, in which case the unbiased estimator of a real-valued function $f(p), p = (p_0,p_1,\cdots,p_r)$ is unique. In general, this estimator has the serious fault of not being range preserving; that is, its value may fall outside the range of f(p). In this article, a condition on a real-valued function f is derived that is necessary for the unbiased estimator to be range preserving that this is sufficient when n is large enough.

  • PDF

Distribution of Fall-Applied N in Various Parts of Satsuma Mandarins (가을에 시용한 질소의 온주밀감 수체 부위별 분포)

  • Kang, Young-Kil;U, Zang-Kual;Kim, Yoeng-Chan
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.33 no.5
    • /
    • pp.325-332
    • /
    • 2000
  • To determine the distribution and recovery of fall-applied N in various parts of satsuma mandarins (Citrus unshiu Marc). $19.68g\;N\;tree^{-1}$ as urea containing 5 atom % $^{15}N$ and 58 kg$K_2O$ $ha^{-1}$ were broadcast-applied to 11 years old 'Miyagawa Wase' grown at a spacing of $2.7{\times}2.7m$ on 18 November 1998. Nitrogen, $P_2O_5$, and $K_2O$ were applied at 104, 308, and $62kg\;ha^{-1}$ on 22 March and N and $K_2O$ at 42 and $83kg\;ha^{-1}$ on 15 June 1999. Two trees were excavated on 15 June and 8 December 1999, respectively. In mid-June, whole tree contained $168.2g\;N\;tree^{-1}$ of which 11.9, 42.1, 29.7, and 16.3% were in fruits, leaves, stems, and roots, respectively. In early December, total tree N averaged $169.8g\;tree^{-1}$ and fruits accounted for 27.6%, leaves 36.4%, stems 22.8%, and roots 13.2% of total tree N. Regardless of harvest date, N derived from fertilizer was highest in newly developed tissues. In mid June, the tree recovered 18.5% ($3.63g\;tree^{-1}$) of fertilizer N. Fruits accounted for 21.1%, leaves for 50.4%, stems for 21.5%, and roots for 7.9% of fertilizer-derived N in the tree, respectively. In early December, the tree recovered 17.0% of fertilizer N. Fruits contained 39.6%, leaves 40.5%, stems 14.5%, and roots 5.3% of fertilizer-derived N in the tree respectively. Comparing with total tree N, a higher proportion of fertilizer-derived N was allocated to metabolically active tissues while a less proportion to old tissues regardless of harvest date.

  • PDF

Alternative Methods for Classification on Weathered Strata (풍화토층의 구분을 위한 시험법의 적용)

  • Son, Young-Hwan;Noh, Soo-Kack;Kim, Seong-Pil;Chang, Pyoung-Wuck
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.51 no.3
    • /
    • pp.63-69
    • /
    • 2009
  • The undisturbed specimens used in this research were sampled in the field by the sequential sampling method. In addition, four testing methods were applied to identify for the characteristics and classification of weathered strata. N-value by standard penetration test was obtained from in the field and then analyzed using normalization method. Other methods such as X-ray grain size distribution, X-ray fluorescence spectroscopy(XRF), and fall cone test were carried out in the lab. These analyzed results indicate that distribution of particle, composition of minerals are changed in accordance with the degree of weathering, unusual strata and depth. Consequently, the weathered strata can be extensively separated into two parts according to the test results and each part was shown different in the strata characteristics. It can be prospected that mechanical characteristics should be different, even though mechanical tests were not applied. Furthermore, these results not only make up for the error by one testing method but also contribute more effectively and economically to the design and the construction.

Effect of Density Variation of High Tenacity PET Interlace Yarn on the Physical Properties of Pack Style Shock Energy Absorber (고강력 PET Interlace Yarn 밀도변화가 Pack Style Shock Energy Absorber의 물성에 미치는 영향)

  • Cho, Jin Won;Kwon, Sang Jun;Choe, Jong Deok;Kim, Sang Tae;Ji, Byung Chul;Yang, Seong Baek;Yeum, Jeong Hyun
    • Textile Coloration and Finishing
    • /
    • v.27 no.2
    • /
    • pp.132-141
    • /
    • 2015
  • Fall-arrest systems(maximum arrest force and allowable free-fall) have been widely applied to provide a safe stop during fall incidents for various industrial activities. Fabric structure affects on the mechanical properties of shock energy absorber. The object of this study is to perform the basic research for the evaluation of the capacity of fall arrest energy absorber in relation to the different interlace yarn density. In this work, pack style energy absorber was prepared by weaving 10 types(Interlace yarn density used high tenacity PET 1000D : 60, 59, 58, 57, 56, 55, 54, 53, 52, 51). The paper presents the results of theoretical investigations of the performance of adjustable absorber during fall arrest. Dynamic load tests based on the EU fall protection equipment standard(CE : EN355:2002) were conducted. Results showed that the maximum arrest force by dynamic load test of energy absorber was satisfied with global standard(below 6,000N). Also, Maximum allowable free-fall of energy absorber showed below 1.75m.

Effect of Nitrogen Application Rates on Nitrous Oxide Emission during Crop Cultivations in Upland Soil

  • Lee, Jong-Eun;Yun, Yeo-Uk;Choi, Moon-Tae;Jung, Suck-Kee;Nam, Yun-Gyu;Pramanik, Prabhat;Kim, Pil-Joo
    • Korean Journal of Environmental Agriculture
    • /
    • v.31 no.3
    • /
    • pp.205-211
    • /
    • 2012
  • BACKGROUND: Generally, nitrogen (N) fertilization higher than the recommended dose is applied during vegetable cultivation to increase productivity. But higher N fertilization also increases the concentrations of nitrate ions and nitrous oxide in soil. In this experiment, the impact of N fertilization was studied on nitrous oxide ($N_2O$) emission to standardize the optimum fertilization level for minimizing $N_2O$ emission as well as increasing crop productivity. Herein, we developed $N_2O$ emission inventory for upland soil region during red pepper and Chinese milk vetch cultivation. METHODS AND RESULTS: Nitrogen fertilizers were applied at different rates to study their effect on $N_2O$ emission during red pepper and Chinese milk vetch cultivation. The gas samples were collected by static closed chamber method and $N_2O$ concentration was measured by gas chromatography. The total $N_2O$ flux was steadily increased due to increasing N fertilization level, though the overall pattern of $N_2O$ emission dynamics was same. Application of N fertilization higher than the recommended dose increased the values of both seasonal $N_2O$ flux (94.5% for Chinese cabbage and 30.7% for red pepper) and $N_2O$ emission per unit crop yield (77.9% for Chinese cabbage and 23.2% for red pepper). Nitrous oxide inventory revealed that the $N_2O$ emission due to unit amount of N application from short-duration vegetable field in fall (autumn) season (6.36 kg/ha) was almost 70% higher than that during summer season. CONCLUSION: Application of excess N-fertilizers increased seasonal $N_2O$ flux especially the $N_2O$ flux per unit yield during both Chinese cabbage and red pepper cultivation. This suggested that the higher N fertilization than the recommended dose actually facilitates $N_2O$ emission than boosting plant productivity. The $N_2O$ inventory for upland farming in temperate region like Korea revealed that $N_2O$ flux due to unit amount of N-fertilizer application for Chinese cabbage in fall (autumn) season was comparatively higher than that of summer vegetables like red pepper. Therefore, the judicious N fertilization following recommended dose is required to suppress $N_2O$ emission with high vegetable productivity in upland soils.