• Title/Summary/Keyword: combining effect

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Meta-Analysis of Intervention Research on Social Work Practice (사회복지실천 프로그램에 대한 메타분석 : 집단프로그램의 효과크기를 중심으로)

  • Lee, Sang-Gyun
    • Korean Journal of Social Welfare
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    • v.40
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    • pp.131-156
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    • 2000
  • Many different intervention methods have been developed to resolve the problem of clients, but research studies evaluating the effectiveness of such practices can be overwhelming to social workers because of the conflicting results of them. In this study, meta-analysis was used to make sense of this research, offering the general effect size of social work practice. Meta-analysis can answer the question, "how effective is the intervention?" beyond the question, "is the intervention effective?". It can integrate the fragmentated results of research studies and provide the guidelines for best practice. Combining the results of the 16 research studies, this study computed the general effect size of social work interventions. The mean d index was. 6636 (95 percent confidence interval of .5355, .8018). Conversion to Cohen's $U_3$ statistics allows for the inference that three-fourths (74.7%) of the clients who participated in an intervention group did better than the average clients of non-intervention group. This means that social work interventions are practically helpful to seven of every 10 clients who experience them. In conclusion, this study recommended the usefulness of meta-analysis, which can provide the intervention strategies based on empirical research and guide the best approaches.

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Springback FE modeling of titanium alloy tubes bending using various hardening models

  • Shahabi, Mehdi;Nayebi, Ali
    • Structural Engineering and Mechanics
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    • v.56 no.3
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    • pp.369-383
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    • 2015
  • In this study, effect of various material hardening models based on Holloman's isotropic, Ziegler's linear kinematic, non-linear kinematic and mixture of the isotropic and nonlinear kinematic hardening laws on springback prediction of titanium alloy (Ti-3Al-2.5V) in a tube rotary draw bending (RDB) process was investigated with presenting the keynotes for a comprehensive step by step ABAQUS simulation. Influence of mandrel on quality of the final product including springback, wall-thinning and cross-section deformation of the tube was investigated, too. Material parameters of the hardening models were obtained based on information of a uniaxial test. In particular, in the case of combined iso-nonlinear kinematic hardening the material constants were calibrated by a simple approach based on half-cycle data instead of several stabilized cycles ones. Moreover, effect of some material and geometrical parameters on springback was carried out. The results showed that using the various hardening laws separately cannot describe the material hardening behavior correctly. Therefore, it is concluded that combining the hardening laws is a good idea to have accurate springback prediction. Totally the results are useful for predicting and controlling springback and cross-section deformation in metal forming processes.

Interference Effect of Microwave Oven Noise to Wireless LAN Using a GTEM Cell (GTEM Cell을 이용한 전자레인지 잡음이 무선 랜에 미치는 간섭 영향 분석)

  • Chung, Yeon-Choon;Jeon, Sang-Bong;Kwun, Suk-Tai;Yun, Jae-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.3
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    • pp.240-247
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    • 2009
  • In this paper, we proposed the method of the interference evaluation between the microwave oven noise and the wireless LAN(Local Area Network) by using the GTEM cell. We used microwave oven noise in time to assess the interference unintentional noise effects on wireless LAN and realized by combining an AM(Amplitude Modulation) modulator and a FM(frequency Modulation) modulator. Also the GTEM cell can be used to guarantee the reliability by the evaluations of the frequency and time responses. As measurement results for the APD(Amplitude Probability Distribution) of the interfering noise we analyzed the effect of microwave oven noise to the throughput of wireless LAN.

Sedative Effect of Sublingual Midazolam after Oral Chloral Hydrate or Hydroxyzine in Children (소아 진정시 Chloral Hydrate, Hydroxyzine복용 후 Midazolam의 점막하 투여 용량에 따른 진정효과에 관한 연구)

  • Lee, Hyun-Jung;Baek, Kwang-Woo;Jung, Sang-Hyuk
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.8 no.1
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    • pp.16-21
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    • 2008
  • Recently combining regimen of minimal doses of chloral hydrate, hydroxyzine and midazolam is good in sedation of children. Midazoalm, water soluble benzdiazepine, has rapid onset and relatively short duration of action. And midazolam has prospective amnesic effect. With these advantages midazolam is popular in conscious sedation for children. This study was to reveal the dose-dependency of behavior and physiologic effects of sublingual midazolam. Sedation records were surveyed retrospectively, of which the patients admitted from April, 2005 to July, 2007. we assigned three groups according the dose of midazolam, 0.1 mg/kg, 0.2 mg/kg and 0.3 mg/kg, respectively and the behavioral evaluation was analyzed with Houpt scale statistically. Combined sublingual midazolam increased the success rate in sedation and the vital signs were stable during sedation.

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Donor Country's Fiscal Status and ODA Decisions before and after 2008 Global Financial Crisis

  • Ahn, Hyeonmi;Park, Danbee
    • The Journal of Industrial Distribution & Business
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    • v.9 no.1
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    • pp.25-38
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    • 2018
  • Purpose - The purpose of this study is to empirically investigate the impact of donor's fiscal status on aid decisions before and after the 2008 global financial crisis. The effects on aid can change depending on the donor country's fiscal status and the period of financial crisis. Research design, data, and methodology - A fixed effect regression and dynamic panel GMM is conducted using a comprehensive dataset combining 31 donor and 167 recipient countries during 1996-2015. The key explanatory variable is central government debt-to-GDP ratio of donor country. Recipient countries' GNI per capita, population, governance indicators, and bilateral trade-to-GDP ratio between donor and recipient countries are included as control variables. Results - We can confirm the relationship between donor country's fiscal status and aid flow. The cyclical component of government debt is found to have a negative impact on grant decisions particularly after the 2008 global financial crisis. This effect becomes larger in the countries with high government debt-to-GDP ratio. ODA decisions from the countries with low financial constraint do not significantly affected by the recipient countries' factors such as GNI, population, and governance indicator. Conclusions - Based on the empirical results of this study, the source of aid should be diversified by incorporating private sector and innovative financing sources.

Simplified robustness assessment of steel framed structures under fire-induced column failure

  • Jiang, Binhui;Li, Guo-Qiang;Yam, Michael C.H.
    • Steel and Composite Structures
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    • v.35 no.2
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    • pp.199-213
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    • 2020
  • This paper proposes a Global-Local Analysis Method (GLAM) to assess the progressive collapse of steel framed structures under fire-induced column failure. GLAM obtains the overall structural response by combining dynamic analysis of the heated column (local) with static analysis of the overall structure (global). Test results of two steel frames which explicitly consider the dynamic effect during fire-induced column failure were employed to validate the proposed GLAM. Results show that GLAM gives reasonable predictions to the test frames in terms of both whether to collapse and the displacement verse temperature curves. Besides, several case studies of a two-dimensional (2D) steel frame and a three-dimensional (3D) steel frame with concrete slabs were conducted by using GLAM. Results show that GLAM gives the same collapse predictions to the studied cases with nonlinear dynamic analysis of the whole structure model. Compared with nonlinear dynamic analysis of the whole structure model, GLAM saves approximately 70% and 99% CPU time for the cases of 2D and 3D steel frame, respectively. Results also show that the load level of a structure has notable effects on the restraint condition of a heated column in the structure.

A Study on the Improvement Policy of the Localization Parts of the Defense Sector (국방분야 부품국산화개발 정책개선 방안)

  • Jung, Suk-Yun;Eom, Jung-Ho
    • Journal of National Security and Military Science
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    • s.15
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    • pp.117-151
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    • 2018
  • The development of local defense parts has played a role a pure function such as maintenance of stable procurement source of military goods, provision of timely supply, establishment of self-defense base, creation of import substitution effect considering the whole life-cycle cost, reduction of foreign currency and protection of domestic defense industry. However, as the development success rate is deteriorating, it is time to analyze the related policies and improve the system. In order to improve the success rate of development of parts for the defense sector, it is necessary to unify the separated policies by the development-related departments and strengthen the policy support for the development companies to actively participate in the development. In addition, it is necessary to improve the paradigm for the selection of development items and change the authority of selecting development items and to delegate authority to create synergies. Parts localization development policy improvement is military support side it will contribute to strengthening defense power management by organically combining with technological development aspect and economical aspect. Development items will be linked to defense exports, which will have a remarkable effect on sales growth and job creation effects. The development of local defense parts is spreading.

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Diamond-like Carbon Tribological Endurance using an Energetic Approach

  • Alkelae, Fathia;Jun, Tea-Sung
    • Tribology and Lubricants
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    • v.37 no.5
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    • pp.179-188
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    • 2021
  • Reputed for their low friction coefficient and wear protection effect, diamond-like carbon (DLC) materials are considered amongst the most important lubricant coatings for tribological applications. In this framework, this investigation aims to elucidate the effect of a few operating parameters, such as applied stress and sliding amplitude on the friction lifetime of DLC coatings. Fretting wear tests are conducted using a 12.7 mm radius counterpart of 52100 steel balls slid against a substrate of the same material coated with a 2 ㎛ thickness DLC. Approximately, 5 to 57 N force is applied, generating a maximum Hertzian contact pressure of 430 to 662 MPa, corresponding to the applied force. The coefficient of friction (CoF) generates three regimes, first a running-in period regime, followed by a steady-state evolution regime, and finally a progressive increase of the CoF reaching the steel CoF value, as an indicator of reaching the substrate. To track the wear scenario, interrupted tests are performed with analysis combining scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), 3D profilometer and micro-Raman spectroscopy. The results show two endurance values: one characterizing the coating failure (Nc1), and the other (Nc2) indicating the friction failure which is situated where the CoF reaches a threshold value of μth = 0.3 in the third regime. The Archard energy density factor is used to determine the two endurance values (Nc1, Nc2). Based on this approach, a master curve is established delimitating both the coating and the friction endurances.

The Effect of Delivery Food on Customer Emotional Response and Repurchase Intention

  • CHA, Seong-Soo;SHIN, Mee-Hye
    • The Korean Journal of Food & Health Convergence
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    • v.7 no.2
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    • pp.1-10
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    • 2021
  • The purpose of this study is to examine the impact of the service quality of delivery food on customers' emotional response and repurchase intention during the COVID19 pandemic. The proposed research model examined the effect on the service quality, customer sentiment response, and repurchase intention of delivery food. A questionnaire was distributed and measured for 300 consumers who had experience using food delivery services in the last 30 days. The questionnaires from previous researches were revised to fit the purpose of the present study. The survey results were analyzed to verify the reliability and validity of the measured variables. To verify the hypotheses a Structural Equation Modelling (SEM) was used for the study. The results showed that taste, price fairness, and package design positively affected emotional response; moreover, repurchase intention was enhanced by emotional response. This research analyzed the relationships between service qualities of delivery food, emotional response, and repurchase intention when customers consume delivery food during COVID19 in Korea. This study extends the delivery food literature by combining customers' emotional behavior with SEM model. The result suggested competitive strategic plans and development directions of food delivery companies in the rapidly increasing food delivery industry, providing implications for further research.

Effect of Resource Allocation in Differential Distributed Cooperative Networks with Mixed Signaling Scheme (혼합된 변조 방식을 적용한 차등 분산 협력 네트워크의 자원 할당 효과)

  • Cho, Woong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.6
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    • pp.1131-1136
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    • 2020
  • Cooperative networks enhance the performance of communication systems by combining received signals from the several relay nodes where the source node transmits signals to relay nodes. In this paper, we analyze the effect of resource allocation in cooperative networks. We assume that the cooperative networks use the conventional modulation scheme between the source and relay nodes, and adopt space-time code between the relays and destination node. Both the synchronous and differential modulations are applied for the conventional scheme and differential modulation is used for the space-time code. We consider relay location and energy allocation for resource allocation, and the performance of cooperative networks depending on the number of relay is also investigated.