• Title/Summary/Keyword: repeated impact

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Biological Control of the Pentatomid Stink Bug, Eocanthecona furcellata(Wolff.), by using their Parasitoid, Psix striaticeps Dodd, in Sericulture

  • Singh, R.N.;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • v.5 no.1
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    • pp.13-22
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    • 2002
  • Stink bug, Canthecona furcellatta (Hemiptera: Pentatomidae), is an important predator of silkworm larvae. Nymphs and adult attack the early stage silkworm larvae and causes about 10-15 per cent loss to silk industry. Synthetic organic pesticides has tremendous impact on minimizing the pest population but repeated and frequent use has created problems of residual toxicity, development of resistance to insecticides, pest resurgence and out break, phyto-toxicity and hazards to non target species and beneficial organism. Silkworms are very sensitive to pesticides; therefore, attempt has made to control the bug population through introduction of its native natural enemies in the silkworm-rearing field. Biological control has tremendous scope in sericulture because it is eco-friendly in nature and non-harmful farmers. Native natural enemies have been screened. Psix striaticeps, Trissolcus spp. and Telenomus spp. have been recorded as the most potential parasitoid against pentatomid bug. Life cycle, sex ratio and other various attributes of the par-asitoids have been recorded. The parasitization potential of the parasitoid is very high and they have the ability to discriminate between parasitized and unpar-asitized host. Mass propopagation technique under laboratory condition has been standaydized.

Evaluation of the Influence of Blast Vibration on Machine Tool Accuracy (발파진동으로 인한 공작기계 가공정도의 영향 평가)

  • Lee, JinKab
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.4790-4795
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    • 2014
  • The machine tool is used widely to manufacture and trial manufactured goods in many machinery industries. Blast-induced ground vibration may have an environmental impact, such as damage to the adjacent structures and facilities. This study examined the influence of blast vibration on the accuracy of machine tools. The blast vibration and vibration of machine tools was measured to evaluate the influence of blast vibration on machine tools. Based on the evaluation of the vibration limit of machine tools, the vibration criteria for machine tools in this study were SLIGHTLY ROUGH~ROUGH. By repeated blast vibration, machine tools are more likely show reduced accuracy.

Oral hygiene maintenance in patients with dental implants following oral health education (임플란트 보유자의 진료기관 내 구강보건교육경험에 따른 구강건강관리 수준)

  • Yu, Jin-Sil;Park, Hye-Young;Bok, Hye-Jung;Lee, Jung-Hwa;Kim, Hye-Jin
    • Journal of Korean society of Dental Hygiene
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    • v.20 no.4
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    • pp.469-478
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    • 2020
  • Objectives: The aim of this study was to investigate the impact of oral hygiene education provided by dental hygienists in patients with dental implants. Methods: Data were obtained from a survey that involved 300 patients who had one or more dental implants. Based on the calculated sample size (n = 274), 300 questionnaires were used for further analyses. Results: The patients who received oral hygiene education had higher levels of satisfaction after dental implant surgery (p<0.05). Patients who had repeated educational sessions, in the form of interactive or hands-on sessions or lectures, with continuous feedback had higher scores for oral hygiene maintenance (p<0.05). Conclusions: This study indicated that patients who received oral hygiene education, in the form of interactive or hands-on sessions or lectures, with continuous post-educational feedback were better at maintaining oral hygiene.

Resource Allocation Algorithm for Multi-cell Cognitive Radio Networks with Imperfect Spectrum Sensing and Proportional Fairness

  • Zhu, Jianyao;Liu, Jianyi;Zhou, Zhaorong;Li, Li
    • ETRI Journal
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    • v.38 no.6
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    • pp.1153-1162
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    • 2016
  • This paper addresses the resource allocation (RA) problem in multi-cell cognitive radio networks. Besides the interference power threshold to limit the interference on primary users PUs caused by cognitive users CUs, a proportional fairness constraint is used to guarantee fairness among multiple cognitive cells and the impact of imperfect spectrum sensing is taken into account. Additional constraints in typical real communication scenarios are also considered-such as a transmission power constraint of the cognitive base stations, unique subcarrier allocation to at most one CU, and others. The resulting RA problem belongs to the class of NP-hard problems. A computationally efficient optimal algorithm cannot therefore be found. Consequently, we propose a suboptimal RA algorithm composed of two modules: a subcarrier allocation module implemented by the immune algorithm, and a power control module using an improved sub-gradient method. To further enhance algorithm performance, these two modules are executed successively, and the sequence is repeated twice. We conduct extensive simulation experiments, which demonstrate that our proposed algorithm outperforms existing algorithms.

A Case Study on Overseas Policy for Effective Conservation of Natural Resources (자연자원의 효율적인 보전을 위한 해외정책 사례 연구)

  • Yoon, Ho-Jung;Yeom, Sung-Jin
    • Journal of Environmental Science International
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    • v.29 no.11
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    • pp.1033-1054
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    • 2020
  • Repeated use of land is depleting future resources and causing many ecological problems, prompting the need for a natural resource policy focusing on effective conservation. This study aims to identify methods based on international cases useful for introducing sustainable conservation of domestic natural resources. Currently, South Korea has developed and enforced many management and evaluation strategies for natural resources. However, due to limitations on policies and management, they show signs of strain. Therefore, this study compares and analyzes international conservation policies for nature and scenery, such as Germany's impact mitigation regulation, the USA's HEA (habitat equivalency analysis) and REA (resource equivalency analysis) policies, and Japan's three laws for landscape and greenery, to achieve the following three goals: first, find natural resources suitable for South Korea and define them. Second, plan goals for mitigation of total natural resources and build a basis for them. Third, establish effective complete plans for evaluating the total amount of natural resources.

Effect of a Mentoring Program as a Strategy for Retention of Clinical Nurses (임상간호사 유지 전략으로서 멘토링 프로그램의 효과)

  • Lee, Byoung-Sook;Park, Jeong-Sook;Lee, Jeong-Hee;Hong, Sun-Nam
    • Journal of Korean Academy of Nursing Administration
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    • v.16 no.1
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    • pp.48-58
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    • 2010
  • Purpose: The purpose of this study was to identify the effect of a mentoring program as a strategy for the retention of clinical nurses. Method: Research subjects were 20 mentors, 20 mentees and 22 clinical nurses for a control group of mentees. A mentoring program was developed by an expert committee and applied to the experimental group for six months. Data were collected at three and six months after the application of the program from September, 2008 to March, 2009. Data were analyzed using $x^$-test, t-test, Repeated Measures ANOVA, One-way ANOVA in SPSS/Win 15.0 Program. Results: Job satisfaction, organizational commitment, empowerment, and carrier commitment in the mentees of the experimental group were significantly higher than the nurses of the control group. Intention of resignation in mentees of the experimental group were significantly lower than the nurses of the control group. Also, there were significant interaction between the groups and the times of measurements in all variables. Conclusion: The mentoring program showed positive impact on the variables for maintenance of clinical nurses. Recommendation: Based on these findings, retention strategies using mentoring programs were recommended to reduce clinical nurses' resignation and improve the competency of clinical nurses that leads to the productivity of nursing organizations.

Development of Guardrail End Treatment System using LS-DYNA (LS-DYNA를 이용한 차량방호울타리 단부처리 시설의 개발)

  • IN, Younggun;Shin, Kwanghee;Bae, Kihun
    • Journal of the Society of Disaster Information
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    • v.12 no.3
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    • pp.279-285
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    • 2016
  • Road sides safety barrier system is the last safety during traffic accident. The structural performance of a roadside safety barrier should be kept above expectations. It is possible to protect the passenger's life. End treatment part is installed in the end of the barrier it prevents a phenomenon in which for the vehicle for the guardrail during a vehicle collision it is facility of the absorbing of car crashed impact. By repeated analysis through computer simulation for improving the vehicle crash it will be able to develop crash barriers to respond appropriately to various parameters.

Management of endometrial polyps in infertile women: A mini-review

  • Jee, Byung Chul;Jeong, Hye Gyeong
    • Clinical and Experimental Reproductive Medicine
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    • v.48 no.3
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    • pp.198-202
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    • 2021
  • Considerable disagreement exists regarding whether endometrial polyps should be removed before attempting natural pregnancy and before pregnancy via intrauterine insemination (IUI) or in vitro fertilization (IVF). Through a literature review, we obtained information on the impact of endometrial polyps and polypectomy on fertility outcomes. Several observational studies have suggested that women with unexplained infertility may benefit from endometrial polypectomy for a future natural pregnancy. A few studies reported benefits from endometrial polypectomy in infertile women who plan to undergo IUI. However, no strong evidence supports polypectomy as a way to improve the pregnancy rate in infertile women who plan to undergo IVF or polypectomy during controlled ovarian stimulation for IVF. Although no studies have defined criteria for the polyp size that should be removed in infertile women, clinicians should be aware that small endometrial polyps (<10 mm) sometimes regress spontaneously. Endometrial polypectomy is currently justified in patients with repeated IVF failure, but more studies are needed to verify that endometrial polypectomy itself will eventually increase the pregnancy rate. Although several mechanisms by which endometrial polyps exert a negative effect on fertility have emerged, there is no consensus about the proper management of endometrial polyps in infertile women. Therefore, the management of endometrial polyps should be individualized depending on the patient's situation and clinician's preference.

Concept Analysis of Tacit Nursing Knowledge (혼종모형을 이용한 암묵적 간호지식의 개념분석)

  • Kim, Hyeon Ju;Kim, Joo Hyun
    • Journal of Korean Academy of Nursing
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    • v.48 no.6
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    • pp.637-655
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    • 2018
  • Purpose: The purpose of this qualitative study is to investigate the nature of tacit nursing knowledge practiced in the clinical field in Korea using hybrid models, and to clarify the definitions and attributes of the concept. Methods: The definition and nature of tacit nursing knowledge, obtained through a review of the extensive literature at the theoretical stage of the research, and the analysis of the in-depth interview data conducted by the career nurses in the fieldwork stage, are compared and analyzed. Results: The tacit nursing knowledge was found in three dimensions as knowledge related to the person, the clinical situation work context, the self, the others, and the task. The tacit nursing knowledge was defined as personal nursing knowledge and artistic skills that show up as unconscious behavior patterns, learned informally, and internalizedthrough repeated clinical practice experience based on professional nursing knowledge. Conclusion: Tacit nursing knowledge has been widely used in clinical practice and has been shown to have a great impact, directly or indirectly, on clinical nursing. Therefore, individual and organizational efforts are needed for validation and clarification using the generation, sharing, collection, and peer review of sound implicit nursing knowledge to ensure that it is properly applied.

Flow Characteristics Analysis for the Chemical Decontamination of the Kori-1 Nuclear Power Plant

  • Cho, Seo-Yeon;Kim, ByongSup;Bang, Youngsuk;Kim, KeonYeop
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.1
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    • pp.51-58
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    • 2021
  • Chemical decontamination of primary systems in a nuclear power plant (NPP) prior to commencing the main decommissioning activities is required to reduce radiation exposure during its process. The entire process is repeated until the desired decontamination factor is obtained. To achieve improved decontamination factors over a shorter time with fewer cycles, the appropriate flow characteristics are required. In addition, to prepare an operating procedure that is adaptable to various conditions and situations, the transient analysis results would be required for operator action and system impact assessment. In this study, the flow characteristics in the steady-state and transient conditions for the chemical decontamination operations of the Kori-1 NPP were analyzed and compared via the MARS-KS code simulation. Loss of residual heat removal (RHR) and steam generator tube rupture (SGTR) simulations were conducted for the postulated abnormal events. Loss of RHR results showed the reactor coolant system (RCS) temperature increase, which can damage the reactor coolant pump (RCP)s by its cavitation. The SGTR results indicated a void formation in the RCS interior by the decrease in pressurizer (PZR) pressure, which can cause surface exposure and tripping of the RCPs unless proper actions are taken before the required pressure limit is achieved.