• Title/Summary/Keyword: Kerb

Search Result 7, Processing Time 0.027 seconds

Effect of Herbicide 'Kerb' on Growth of Perennial Ryegrass (Lolium perenne L. 'Accent') and Zoysiagrass (Zoysia japonca 'Zenith') under Shading Treatments (차광조절하에서 제초제 Kerb가 퍼레니얼 라이그래스와 한국잔디의 생육에 미치는 영향)

  • Ham, Tae-Hwan;Yun, Jong-Jin;Lee, Sang-Gi;Ku, Ja-Hyung
    • Asian Journal of Turfgrass Science
    • /
    • v.25 no.1
    • /
    • pp.52-58
    • /
    • 2011
  • In order to investigate an artificially transition method of perennial ryegrass(Lolium perenne L. 'Accent') overseeded on zoysiagrass (Zoysia japonca Zenith') with Kerb (3,5-jichloro-N (1,1-dimethyl-2-propynyl). We observed turfgrass growth and physiological responses of the two turfgrasses under the shading treatments. The experiment was conducted in greenhouse during April- August. Shading was generally using a black shade net product whose the shade level was done into 0, 35 and 75%, actual light intensities were 589, 378 and $135\;{\mu}mol{\cdot}m^{-2}{\cdot}s$ PAR, respectively. The four levels of Kerb treatment were 0, 0.1 0.2, and $0.4\;g{\cdot}m^{-2}$. As shading was getting increased, growth of perennial ryegrass was increased slowly, but zoysiagrass was reduced and almost all of experiments showed significant differences statistically. Perennial ryegrass exhibited inclination that growth was reduced in more than Kerb $0.4\;g{\cdot}m^{-2}$ by shades. On the other hand, it was shown that the growth of zoysigrass was reduced by shades largely and it was not effected by Kerb. Through this study, it was determined that Kerb is effective for elimination of overseeded perennial ryegrass on zoysiagrass. Moreover, when excluding perennial ryegrass under the condition like shade, it is desirable for treating high concentration more than the basic processing amount.

Studies on Weed Control with Herbicides in Soybean Field (콩밭 잡초방제에 관한 연구)

  • Ryang Whan Seung
    • Korean journal of applied entomology
    • /
    • v.10 no.1
    • /
    • pp.31-38
    • /
    • 1971
  • Tolerance test in plastic vat, pot and fold tests were carried out to investigate the selective herbicides for soybean culture in sandy loam. The soybean plants showed great tolerance against herbicides such as Tri-allate (Avadex-BW), Alachlor (Lasso), Butachlor (Machete), Propachlor (Ramrod), Nitrofen (TOK), MO, HE-314, Nitrofen/Dinoseb(TOK/DNBP), and Chlo.oxu.on (Tenoran), and the growth was normal even when each was treated with the herbicides up to 2ft3 times of the recommended concentrations. Soybean plants showed a slight tolerance against Prometryne (Gesagard), Propazine (Gegamil), Diuron (Karmex), Metabromuron (Patoran), Linuron (Lorox) and Swep when each was treated with herbicides up to 1-2 times of the recommended concentrations. Great injury or withering was noticed due to the high sensitivity of soybean to Simazine (CAT) and to Floumetron (Cotoran). In pot and field experiments with herbicides such as Butachlor (Machete), Alachlor (Lasso), Nitrofen (TOK), Kerb, Nitrofen/Dinoseb (TOK/DNBP), Swep, Linuron (Lorox), Simazine (CAT) and PCP, the following results were obtained: Great injuries were noticed with Simazine (CAT). Also, Linuron (Lorox) and Kerb showed a slight injury at early growth stage of soybean, Nitrofen (TOK) , Nitrofen/Dinoseb (TOK/DNEP), Alachlo. (Lasso), Butachlo. (Machete) and Swep had high selectivities for soybean and no injury was noticed. With respect to herbicidal effects there was a greatly significant difference between treated plots and non-treated plots with the exception of Simaaine (CAT) plot in field test. E. crusgalli and C. sanguinalis were tolerant against Simazine(CAT) and Linuron(Lorox). Cyperus and E. annuus were tolerant against Kerb. Great herbicidal effects on grasses were observed in Alachlor (Lasso) and Butachlor (Machete) plots. Among broad-leaf weeds, P. hydropiper and C. album were tolerant against Butachlor (Machete) and Alachlor (Lasso). When soybean was treated with the herbicides such as Alachlor (Lasso) (ai. 150g/10a), Butachlor (Machete) (ai. 300g/10a), Nitrofen (TOK) (ai. 250g/10a), Linuron (Lorox) (ai. 75g/10a) once after seeding, no additional wording was required till harvest.

  • PDF

An Investigation of Road Crossing Behaviour of Older Pedestrians at Unsignalized Crosswalk (무신호 단일로 횡단보도에서 고령 보행자의 횡단행태조사 및 분석)

  • JANG, Jeong Ah;KIM, Junghwa;CHOI, Keechoo
    • Journal of Korean Society of Transportation
    • /
    • v.34 no.3
    • /
    • pp.207-221
    • /
    • 2016
  • In Korea, older pedestrian accounted for 57% of all pedestrian deaths although a ratio of older pedestrian accidents to total pedestrian accidents was only 25.9%. Though ageing population problem becomes more challenging for road safety, little is know about the behaviour of older pedestrian's behaviour. This study aimed to identify road crossing behaviour of older pedestrian at three-lane unsignalized crosswalks using video image analysis and to compare the behaviour of older pedestrian to younger one by indicators including approaching speed, the number of walking steps and other factors. The results showed that there was a difference of approaching time at kerb, waiting time at kerb, the number of glances at kerb, and the number of glances at crossing between two groups under the situation of car approaching to crosswalks. It also showed that older pedestrian usually spent 1.16 times more than younger pedestrian to walk across the crosswalk with only 84.4% of walking speed of younger pedestrian. The number of steps of older pedestrian for road crossing was 1.12 times higher with 90% shorter steps than younger pedestrian. It was concluded that older pedestrian usually decided to walk across in case of 1.67 times longer headway than younger pedestrian's decision. These results could be applied in road and facility design for better safety of older pedestrians.

A Case Study on Chloride Corrosion for the End Zone of Concrete Deck Subjected to De-icing Salts Added Calcium Chloride (염화칼슘이 함유된 제설제로 인한 콘크리트 바닥판 단부의 염해에 관한 사례 연구)

  • Chung, Jee-Seung;Kim, Bo-Heon;Kim, Il-Sun
    • Journal of the Korean Society of Safety
    • /
    • v.29 no.6
    • /
    • pp.87-93
    • /
    • 2014
  • In this study, the reinforced concrete rahmen bridge damaged by the chloride attack was investigated. According to the investigation, the degraded concretes on cantilever kerb and end part were intensively observed. Thus, the chloride content test and half-cell method were performed to evaluate the degraded parts. As a result, the contents of chloride on degraded parts were C and D grade. On the other hand, the half-cell potential values of rebar in degraded concrete were measured with the minor corrosion. This rebar corrosion is expected to progressing. Chloride content D grade is due to expansion pressure by corrosion of rebar and freeze-thaw by permeate water, could see progresses rapidly degradation. In order to prevent chloride attack to concrete deck caused by deicing salts, corresponding to the chloride critical concentration must maintain grade b or at least grade c. Chloride condition evaluation standard apply to evaluation of marine structure chloride attack with chloride attack by deicing salts.

Effects of Oyootang and shinchulsan Extract on the Contraction of Isolated Guinea pig's Trachea Smooth Muscle (오요탕(五拗湯) 및 신출산(神朮散)이 GUINEA PIG의 기관지(氣管支) 평활근(平滑筋)에 미치는 영향(影響))

  • Lee, Si-Hyeong
    • The Journal of Internal Korean Medicine
    • /
    • v.14 no.1
    • /
    • pp.1-16
    • /
    • 1993
  • This study was carried out to investigate the effect of Oyootang and Shinchulsan extract on the contractile force of the isolated guinea pig trachea smooth muscle and elucidate its mechanism The result were obtained as follow: 1. The isolated trachea smooth muscle was suspended in the organ bath with oxygenated kerb's Henseleit bicarbonate buffer solution at $37^{\circ}C$, and the developed tension by the drug was recorded with isometric tranducer(Nacro F-60). The resting tension was approximately 0.5g 2. The contractile response of the trachea smooth muscle of the isolated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootang and Shinchulsan extract. 3. The contractile response of the trachea smooth muscle of the isolated guinea pig by acetylcholine $10^{-4}M$ was considerably inhibited by Oyootang and Shinchulsan extract. 4. The contractile response of the trachea smooth muscle of the isolated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootanghabshinchulsan extract. 5. The contractile response of the trachea smooth muscle of the isolated guinea pig by acetylcholine $10^{-4}M$ was significantly inhibited by Oyootanghabshinchulsan extract. 6. The contractile response of the trachea smooth muscle of the iso-lated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootang, Shinchulsan and its constituent herbs extract. 7. The contractile response of the trachea smooth muscle of the iso-lated guinea pig by acetylcholine $10^{-4}M$ was significantly inhibited by Oyootang, Shinchulsan and its constituent herbs extract.

  • PDF

An Impact of Empathy on the Job Satisfaction and Turnover Intention - Focused on the Mediating Effect of Job Stress - (조직구성원의 공감이 직무만족과 이직의도에 미치는 영향 - 직무스트레스의 매개효과 -)

  • Choi, Su-Heyong
    • Management & Information Systems Review
    • /
    • v.35 no.4
    • /
    • pp.229-250
    • /
    • 2016
  • This research was conducted to examine the effects of cognitive and emotional empathy amongst employees, and its contribution to the enhancement of the effectiveness of an organization. Further, 'job stress' was used as the moderating value. For this purpose, examination procedures were based on theoretical ground drawn from previous research papers, and an appropriate hypothesis established. Statistical methods were also employed to obtain empirical evidence. This study consisted of four variables. The independent variable is categorised into the factors of cognitive and emotional empathy. Job stress as the moderating value as well as job satisfaction and turnover intention as members of the dependent variable. A survey was carried out targeting employees of numerous firms working in teams, and a total of 324 samples were collected and processed by the software package SPSS 21 for windows as a means to verify the set study model and hypothesis. The results of the study are as follows: The two factor of cognitive and emotional empathy did not present with any significant effects. However, cognitive empathy in relation to job stress was found to inflict negative effects. The study also found the two factors to play a significant role in asserting positive effects on an individual's level of satisfaction on his/her job. While the study further explained that cognitive understanding had the tendency to impose negative effects on the turnover intention, emotional empathy did not demonstrate significant effects. Job related stress negatively effects the level of satisfaction of an individual's given task or a job and positive relation with turnover intention. It was confirmed that job stress had a degree of intermediary role upon other factors such as empathy, job satisfaction and turnover intention. The results of the study purported that empathy can raise the level of an individual's job satisfaction and kerb turnover intention. In order to accomplish depreciated levels of job related stress, it is vital that firms consistently input fervent endeavours to be subserved. It must be able to create an environment wherein employees may enjoy the improved structure of the company to empathies with each other. These transitions would allow firms to achieve maximum efficiency and improvements on the effectiveness of an organization.

  • PDF

A study on the way to improve strength of LTV's FRP structures by optimizing laminated structure (전술차량 FRP 구조물 적층 구조 최적화를 통한 강도개선 방안 연구)

  • Kim, Seon-Jin;Park, Jin-Won;Kim, Sung-Gon;Kang, Tae-Woo;Shin, Cheol-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.5
    • /
    • pp.468-476
    • /
    • 2019
  • This paper presents the means of improving the strength of LTV's FRP structure for resolve and prevent quality problems. LTV secures enough kerb weight by applying FRP materials at hood and rear van assembly. However, because of FRP's inherent limitations, many initial quality problems such as crack at connections have occurred. Moreover, hood assy' is concerned about fall of endurance, because hood assy' have operated in abnormal condition. Therefore, this study executes lamination structure optimizations of FRP structure for improving bending strength. As a results, hood and rear van's bending strength at connections is improved 8.1 times and 1.5 times, respectively. Also hood assy's plate secures endurance life and improve 1.7 times of critical load about abnormal operating conditions through 1.4 times improvement of bending strength.