• Title/Summary/Keyword: cross-national study

Search Result 4,578, Processing Time 0.031 seconds

Effect of Guide Nozzle Shape on the Performance Improvement of a Very Low Head Cross Flow Turbine

  • Chen, Zhenmu;Singh, Patrick Mark;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
    • /
    • v.17 no.5
    • /
    • pp.19-26
    • /
    • 2014
  • The cross flow turbine attracts more and more attention for its relatively wide operating range and simple structure. In this study, a novel type of micro cross flow turbine is developed for application to a step in an irrigational channel. The head of the turbine is only H=4.3m and the turbine inlet channel is open ducted type, which has barely been studied. The efficiency of the turbine with inlet open duct channel is relatively low. Therefore, a guide nozzle on the turbine inlet is attached to improve the performance of the turbine. The guide nozzle shapes are investigated to find the best shape for the turbine. The guide nozzle plays an important role on directing flow at the runner entry, and it also decreases the negative torque loss by reducing the pressure difference in Region 1. There is 12.5% of efficiency improvement by attaching a well shaped guide nozzle on the turbine inlet.

Fatigue Strength Evaluation of Self-Piercing Riveted Al-5052 Joints (셀프 피어싱 리베팅한 Al-5052 접합부의 피로강도 평가)

  • Kang, Se Hyung;Hwang, Jae Hyun;Kim, Ho Kyung
    • Journal of the Korean Society of Safety
    • /
    • v.30 no.3
    • /
    • pp.1-6
    • /
    • 2015
  • Self-piercing riveting (SPR) is receiving more recognition as a possible and effective solution for joining automotive body panels and structures, particularly for aluminum parts and dissimilar parts. In this study, static strength and fatigue tests were conducted using coach-peel and cross-tension specimens with Al-5052 plates for evaluation of fatigue strength of the SPR joints. For the static experiment results, the fracture modes are classified into pull-out fracture due to influence of plastic deformation of joining area. During the fatigue tests for the coach-peel and cross-tension specimens with Al-5052, interface failure mode occurred on the top substrate close to the rivet head in the most cycle region. There were relationship between applied load amplitude $P_{amp}$ and life time of cycle N, $P_{amp}=715.5{\times}N^{-0.166}$ and $P_{amp}=1967.3{\times}N^{-0.162}$ were for the coach-peel and cross- tension specimens, respectively. The finite element analysis results for specimens were adopted for the parameters of fatigue lifetime prediction. The relation between SWT fatigue parameter and number of cycles was found to be $SWT=192.8N_f^{-0.44}$.

Seismic analysis of a masonry cross vault through shaking table tests: the case study of the Dey Mosque in Algiers

  • Rossi, Michela;Calderini, Chiara;Roselli, Ivan;Mongelli, Marialuisa;De Canio, Gerardo;Lagomarsino, Sergio
    • Earthquakes and Structures
    • /
    • v.18 no.1
    • /
    • pp.57-72
    • /
    • 2020
  • This paper presents the results of a monodirectional shaking table test on a full-scale unreinforced masonry cross vault characterized by asymmetric boundary conditions. The specimen represents a vault of the mosque of Dey in Algiers (Algeria), reproducing in detail the mechanical characteristics of masonry, and the constructive details including the presence of some peculiar wooden logs placed within the vault's abutments. The vault was tested with and without the presence of two steel bars which connect two opposite sides of the vault. The dynamic behaviour of both the vault's configurations were studied by using an incremental dynamic analysis up to the collapse of the vault without the steel bars. The use of an innovative high-resolution 3D optical system allowed measure displacement data of the cross vault during the shake table tests. The experimental results were analysed in terms of evolution of damage mechanisms, and in-plane and out-of-plane deformations. Moreover, the dynamic properties of the structure were investigated by means of an experimental modal analysis.

Alternative Measures for Improvement of Information Literacy as Cross Curricula under the National Curriculum in Korea (국가 수준 교육과정에서 범 교육과정으로서의 정보 활용 능력 위상 강화 방안)

  • Song, Gi-Ho
    • Journal of Korean Library and Information Science Society
    • /
    • v.42 no.2
    • /
    • pp.29-50
    • /
    • 2011
  • An aim of this study is to analyze status of information literacy and propose some ways strengthening its role as a cross-curriculum. Analyses show that information literacy is a basic competency of creative person composing the educational human figure under the national curriculum in Korea. In the school knowledge, its position is a procedural knowledge to create new ideas, also it is a interdisciplinary thinking skill under the instructional method. Therefore, information literacy instruction covering media and ICT literacy should exist as a main cross-curriculum to be a selective subject in the national curriculum. And finally, one of learning skills, its definition should be cleary stated such as information research and access, information analyses and interpretation, information synthesize and presentation.

Per-oral cross-facial sural nerve graft for facial reanimation

  • Jeong, Joohee;Almansoori, Akram Abdo;Park, Hyun-Soo;Byun, Soo-Hwan;Min, Seung-Ki;Choung, Han-Wool;Park, Joo Yong;Choi, Sung Weon;Kim, Bongju;Kim, Soung-Min;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.40
    • /
    • pp.22.1-22.4
    • /
    • 2018
  • Background: Cross-facial nerve graft is considered the treatment of choice for facial reanimation in patients with unilateral facial palsy caused by central facial nerve damage. In most cases, a traditional parotidectomy skin incision is used to locate the buccal and zygomatic branches of the facial nerve. Methods: In this study, cross-facial nerve graft with the sural nerve was planned for three patients with facial palsy through an intraoral approach. Results: An incision was made on the buccal cheek mucosa, and the dissection was performed to locate the buccal branch of the facial nerve. The parotid papillae and parotid duct were used as anatomic landmarks to locate the buccal branch. Conclusions: The intraoral approach is more advantageous than the conventional extraoral approach because of clear anatomic marker (parotid papilla), invisible postoperative scar, reduced tissue damage from dissection, and reduced operating time.

A Study on Outlet Damage Prediction of Pipe Culverts in Forest Road (임도 횡단배수구의 유출구 피해 예측에 관한 연구)

  • Kim, Myung Hwan;Hwang, Jin Seong;Yu, Young Min;Cha, Du Song
    • Journal of Korean Society of Forest Science
    • /
    • v.107 no.3
    • /
    • pp.278-286
    • /
    • 2018
  • This study examined the damage characteristics through investigation for a total of 10 factors (longitudinal position, crossing position, soil type, collecting well volume, outlet position, water apron material, waterway existence, pipe culvert diameter, pipe culvert gradient, pipe culvert height) affecting outlet damages of forest road cross drainage for forest roads in the Research Forest of Kangwon National University. We predicted outlet damages of forest road cross drainage for forest roads using a discriminant analysis Results showed that longitudinal position, crossing position, soil type and pipe culvert height did not affect damages caused to forest road cross drainage. Most influential factors affecting outlet damages were outlet position, waterway existence, pipe culvert diameter, pipe culvert gradient and collecting well volume, respectively. The discriminant ratio calculated from the developed discriminant function was 68.8% which is reasonably reliable.

Effects of using Umbilical Hernia Animals as Breeding Pigs on the Reproductive Traits (배꼽탈장(umbilical hernia)돼지의 종돈 활용이 번식형질에 미치는 영향)

  • Han, Sang-Hyun;Cho, In-Cheol;Cho, Yong-Il;Park, Yong-Sang;Kang, Tae-Young
    • Journal of Veterinary Clinics
    • /
    • v.34 no.2
    • /
    • pp.126-131
    • /
    • 2017
  • This study investigated the incidence rate of umbilical hernia (UH) in pig farms and examined the effect of using them as breeding pigs on reproductive traits. The occurrence of UH ranged from 0.1% to 3.0% in pig farms investigated. UH pigs were found in almost all farms except for a single farm in Jeju Island. Spontaneously occurring UH pigs were selected and used for cross breeding tests. UH-related crosses and their progeny showed significant (P < 0.05) differences in gestation period, the numbers of piglets born and alive, and body weights at birth and $21^{st}$ day comparing to those of the control population. UH-related crosses showed longer gestation period, reduced numbers of piglets, and lighter body weights than those from the control population. Interestingly, reduced number of piglets was about one fourth, suggesting that UH inheritance might play a critical role as a lethal gene during embryogenesis. In addition, UH incidence rate in UH-related crosses was significantly (P < 0.05) higher than that in the control except for UH-cross3. However, in the progeny of control cross, a pig also had UH appearance, indicating that porcine UH might be inherited in recessive inheritance mode. Taken together, the results of this study indicate that UH is one of recessively inherited genetic defect that occurs at ordinary times in pig farms, suggesting that the use of UH animals as sire and/or dam may lead to economic losses due to increased gestation period, reduced numbers of piglets born and alive, and lower growth rates after birth of pigs.

Preliminary Validation Study of the Korean Version of the DSM-5 Level 2 Cross-Cutting Symptom Measure: Depression and Irritability for Parents of Children Aged 6-17 Years

  • Shin, Min-Sup;Kim, Bung-Nyun;Jang, Mirae;Shin, Hanbyul;Seo, Gyujin
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
    • /
    • v.33 no.3
    • /
    • pp.67-72
    • /
    • 2022
  • Objectives: This study investigated the reliability and validity of the Korean version of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) Level 2 Cross-Cutting Symptom Measure-Patient-Reported Outcomes Measurement Information System (PROMIS)-Depression and the Irritability for parents of children aged 6-17 years. Methods: Participants were 190 children diagnosed with depressive disorder (n=14), anxiety disorder (n=21), attention-deficit/hyperactivity disorder (ADHD; n=111), ADHD with anxious depression (n=13), and tic disorder with somatic symptoms (n=31). Patients were 8-15 years of age. The participants' mothers completed the Korean versions of the DSM-5 Level 2 Cross-Cutting Symptom Measure-PROMIS Depression and Irritability (Affective Reactivity Index, ARI), and the Korean Child Behavior Checklist (K-CBCL). Using these data, we calculated the reliability coefficient and examined the concurrent and discriminant validity of the PROMIS Depression and the Irritability (ARI) scales for assessing depression and irritability in children. Results: The reliability coefficient of the PROMIS Depression scale (Cronbach's α) was 0.93. The correlation coefficient with the K-CBCL DSM emotional problem score was 0.71. The PROMIS Depression scale significantly discriminated children with depressive disorders from those with other conditions. The reliability coefficient of the Irritability (ARI) scale was 0.91, suggesting its high reliability. Conclusion: Our results suggest that the Korean version of the DSM-5 Level 2 Cross-Cutting Symptom Measure for Depression and Irritability Scales for parents of children aged 6-17 years is reliable and valid and may be an efficient alternative to the K-CBCL.

Development of a Web-Based Program for Cross-Calibration and Record Management of Radiation Measuring Equipment

  • Park, So Hyun;Lee, Rena;Kim, Kyubo;Ahn, Sohyun;Lim, Sangwook;Cho, Samju
    • Progress in Medical Physics
    • /
    • v.30 no.2
    • /
    • pp.59-63
    • /
    • 2019
  • Purpose: To manage radiation measurement equipment, a web-based management program has been developed in this study. Materials and Methods: This program is based on a web service and Java Server Pages (JSP) and employs compatibility and accessibility. Results: The first step in the workflow has been designed to create accounts for each user or organization and to log in. The program consists of two parts: fields for listed instruments, and measurement information. The instruments for measuring radiation listed in this program are as follows: ionization chambers, survey meters, thermometers, barometers, electrometers, and phantoms. Instrument properties can be put in the recording fields and browsing for associated instruments can be performed. The main part of the program is the cross-calibration for each ion chamber. For instance, the ionization chamber to be used as a relative dosimeter can be registered by cross-calibration data with a reference chamber calibrated by an accredited laboratory. This program supports methods using the central axis transfer theory for cross-calibration for the ionization chambers. The reference and field ionization chambers were placed in a solid water phantom along the beam central axis at two different depths, and then the positions were switched. Each measured value was used for calculating the cross-calibration factor. Conclusions: Because many instruments are used and managed in radiation oncology departments, systematic, traceable recording is very important. The web-based program developed in this study is expected to be used effectively in the maintenance of radiation measurement instruments.

Political Economy of Cross-Border Lobbies and the Stringency of the Rules of Origin Verification (해외로비와 원산지규정 사후검증제도의 엄격성에 대한 정치경제학)

  • Seok-Joon Hwang;Uk Hwang;JinKwon Lee
    • Korea Trade Review
    • /
    • v.45 no.1
    • /
    • pp.155-171
    • /
    • 2020
  • In reality, there are numerous [Note: I advise to change the tone to being more certain, as opposed to offering a possibility. You need to emphasize the seriousness of the conditions that your study wants to talk about] non-tariff trade barriers under free trade agreements, with various stakeholders having different trade-off interests. This study focuses on the rules of origin verification and considers cases in which domestic firms, foreign firms, and domestic consumer groups compete politically for their rent protection in the domestic market. As in Gwande et al. (2006), cross-border lobbies are considered possible wherein foreign firms also lobby the government to influence the decision-making process of how stringently to verify the rules of origin. [Note: Starting here, switch to past tense because a: study intentions above can be in present tense, b: study procedures should be in past tense] In this study, we assumed that all stakeholders form interest groups and present political contributions to the government based on their interests. The stringency of the rules of origin verification was then determined through this political process, and we compared this to a socially optimal one in the analysis. It was found that the verification was less stringent when there was cross-border lobbying than the socially optimal one.