SIMULATION OF SHALLOW FLOWS IN A CIRCULAR BASIN USING COLLOCATED MULTI-BLOCK METHOD

HADIAN MOHAMMAD REZA,ZARRATI AMIR REZA 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1

Assessment of Surface, Structural, and Viscoelastic Properties of Immiscible Polylactic Acid/Polyvinylidene Fluoride Blends

Ali Hadian Rasanani,Babak Kaffashi,Shervin Ahmadi,Javad Seyfi 한국고분자학회 2022 Macromolecular Research Vol.30 No.5

In this study, polylactic acid (PLA)/polyvinylidene fluoride (PVDF) blends were fabricated via solution casting. To eliminate the adverse effect of moistureinduced phase separation, the samples were dried at 60℃. The accelerated drying also reduced the phase separation between the blend components leading to a smaller size of the dispersed phase, i.e., increased interfacial area. Morphology results revealed that, in contrast to PVDF, PLA exhibits a more uniform distribution once used as the dispersed phase. The ratio of β to α crystals in PVDF was increased upon the introduction of PLA. On the other hand, the crystallized PVDF domains improved the PLA crystallinity. Rheological analysis indicated that the viscoelastic response of the 50/ 50 blend was governed by the PVDF phase, which agreed with the fact that PVDF became the matrix phase in that composition. The samples with PVDF as the matrix exhibited a shear-thinning behavior instead of the partial Newtonian behavior of blends with PLA as the matrix. The dynamic mechanical analysis results, further proved our claims from rheological measurements. The damping curves suggested that PVDF as the dispersed phase caused a higher restricting effect on the macromolecular motions, attributed to its dispersion quality. The wettability results showed an increasing trend in the hydrophobicity as the PVDF content increased in the blends. Due to the enhanced β phase content and improved compatibility, PLA/PVDF blends with 30/70 and 50/ 50 compositions show a promising potential to be used in piezoelectric devices.

Map-merging using maximal empty rectangles in a multi-robot SLAM process

Shahram Hadian Jazi 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.6

A map-merging algorithm is proposed where reduced element maps are applied instead of grid maps and the maximal empty rectangles are applied as their features. Simultaneous localization and mapping (SLAM) refer to the process where a robot provides the environment map without any knowledge about its own position. Due to error accumulation, required time, saving lives and reasons alike, applying a single robot in the SLAM process is not justified. In such applications, many robots are to be applied in the SLAM process in a parallel sense. The map-merging process is one of the challenging topics in a multi-robot simultaneous localization and mapping process in producing a global map of the environment. In this study, a centralized algorithm is introduced for map-merging based on maximal empty rectangles as the features of local maps without any knowledge about robots' initial or relative positions. Three examples and one experiment are applied in validating the performance of this newly proposed algorithm. The obtained results indicate that this algorithm can merge local maps with small overlapping areas in relation to the whole map, subject to multiple sources of error due to the difference in scales, diversity of agents applied and measurement noise.

Identity - Based Multiple Key Agreement Scheme

( Massoud Hadian Dehkordi ),( Reza Alimoradi ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.12

In order to protect some important information communicated through an insecure network, a common hidden key must be used. One can produce the common hidden key using key agreement protocols; and this helps to have high security in modern data networks. Today, the designers of public key cryptography protocols try to set the public identity of a system`s users (like their email addresses) as their public key. This not only makes a cryptographic protocol more efficient but also decreases its cost. These protocols are called "identity - based ". In this article, an identity - based multiple key agreement scheme will be presented; this scheme uses the challenge - response method to do the verification. While the number of random values produced in our scheme is the same as other schemes, the number of keys generated in this scheme is much more than what many other key agreement schemes produce,. Therefore, we will have less computational complexities campered with other schems. In this paper, we consider the security of our scheme and consequently,we will show that it satisfies many security conditions such as strong security.

Promoting Fishery Cooperative: Window of Opportunity toward Sustainable Fishery Development (Case Study: Karangsong Village, Indramayu-Indonesia)

하디안 이드하르 야사디타마(Hadian Idhar Yasaditama) 영남대학교 박정희새마을연구원 2018 새마을학연구 Vol.3 No.2

2015년부터 외국 선박 운영을 금지하는 인도네시아 수산 정책이 실시된 이후로 현지 어부들이 어업 자원을 활용할 수 있는 기회가 열렸다. 현지 어부들의 전통적 특성을 감안할 때, 모든 역량 구축 노력은 상향식 방법이 더 적절하다. 따라서 협동조합을 시행 주체로 하는 지역공동체 발전의 개념이 가장 적합한 대안이 될 것이다. 카룽송 (Karangsong) 지역에 있는 미나 스미트라 협동조합 (The Mina Sumitra Cooperative)은 놀라운 매출액과 자산으로 인도네시아에서 가장 성공적인 수산업 협동조합 중 하나다. 따라서 미나 스미트라 협동조합의 경험은 수산업 부문에서 공동체 개발 개념을 기반으로 협동조합을 발전시키는 데 있어 좋은 교훈이 될 것이다. 본 논문은 미나 스미트라 협동조합이 어떻게 카룽송 지역에서 지속 가능한 수산업을 실현하기 위해 지역사회발전의 개념을 성공적으로 구현했는지 분석하고자 한다. 관련된 사례 연구를 실시하기 위해 먼저 수산업 발전, 지역사회 발전과 협동조합에 대한 개념 조사가 이루어졌다. 이 분석은 긴급성의 범위와 협동조합 발전의 패턴, 그리고 지역 사회 개념의 구현으로서 협동조합의 성과에 기반하여 이루어졌다. 연구 결과 어민들의 인간성과 수산업의 경기주기가 협동조합의 발전에 있어서 가장 논리적인 근거임을 확인했다. 기술적인 필요성에 대응하기 위해, 협동조합 발전의 패턴은 수산업의 경기주기의 흐름과 포괄적인 적용 범위 두 가지에 의해 결정지어졌다. 그 결과 협동조합은 어민들의 요구를 충족시켜주는 역할을 할 뿐만 아니라, 수산업의 가치사슬로부터 지역 경제 발전과 지역 문화 보존을 위한 승수 효과도 제공함을 알 수 있다. Since 2015, Indonesia’s fisheries policy in prohibiting the operation of foreign vessels has opened opportunities for local fishermen to utilize fishery resources. Considering the traditional characteristics of Indonesia’s local fishermen, all capacity building efforts are better directed to bottom-up methods. Accordingly, the concept of community development becomes the most suitable alternative, with cooperative media as an implementer. The Mina Sumitra Cooperative in the Karangsong region is one of the most successful fisheries cooperatives in Indonesia, characterized by the remarkable turnover and assets. Therefore, the Mina Sumitra Cooperative experience would become an interesting lesson in the practice of promoting cooperatives based on community development concept in the fisheries sector. This paper aims to analyze how the Mina Sumitra Cooperative successfully implements the concept of community development to realize sustainable fisheries in the Karangsong region. A desk study approach was applied to explore the concept of fisheries development, community development, and cooperative to make a relevant case study. The analysis will be based on the scope of urgency and patterns of cooperative development, as well as outcomes of cooperative as an implementer of the community development concept. Our findings indicate that the human-nature of fishermen and the fisheries business cycle-related are the most logical background of cooperative development. As for responding to technical needs, the patterns of cooperative development are formulated both in accordance with the flow of fisheries business cycle and within comprehensive coverage. As a result, cooperatives not only play a role in fulfilling fishermen’s needs but also provide the multiplier effects from the value chain of the fishery activities for regional economic development and preservation of local culture.

Effect of Service Quality Toward Student Satisfaction and Loyalty in Higher Education

MULYONO, Hardi,HADIAN, Arief,PURBA, Nelvitia,PRAMONO, Rudy Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.10

This study analyzes the effect of quality of services provided to the students' in relation to their satisfaction and loyalty. Respondents in this study were seventh semester students of Universitas Muslim Nusantara Al-Washliyah, the total number of students was 312. Data analysis techniques in this study used was SEM (Structural Equation Modeling) using the SmartPLS program. The results showed that students' satisfaction significantly mediated the correlation between academics and students' loyalty, between non-academic and students' loyalty, between reputation and students' loyalty, and between campus access and students' loyalty; on the other hand, students' satisfaction was not significant in mediating the correlation between program issues and students' loyalty. The findings suggest that it is necessary to improve the quality of lecturers to improve students' academic abilities and communication skills. As far as non-academic aspects are concerned, conducting training and development efforts and increasing awareness programs for administrative staff is important. For the reputation aspect, to carry out several marketing campaigns which predict to have an effect upon students in building positive perceptions of campus has to be executed as well. Meanwhile for access aspect, it should be made certain that every student can have direct access to staff employees, and it is necessary to improve dimensions which can increase students' satisfaction so that students are convinced of their choice of campus and then they are likely to recommend their chosen university and spread positive things about their institutions.

The Single-Allocation Heuristic Hub Location Problem Solving

Davood Jafari,Mahdi Hadian Pour 대한산업공학회 2018 Industrial Engineeering & Management Systems Vol.17 No.3

Hubs are special facilities that consolidate and disseminate flows in many-to-many distribution systems. The hub location problem aims to find locations of hubs and allocate non-hub nodes directly to the hubs. However, this problem is necessary to extend when nodes do not have sufficient demand to justify direct connections between the non-hub nodes to the hubs since such direct connections increase the number of vehicles required and decrease the utilization of vehicles. In this research, after analyzing the definitions of the location of the hub and a variety of location models and their solving algorithms, we solved a case study of the classic Hub Location model algorithm by adding an annual fixed cost to determine the best way to carry goods from one country to another from the top 5 most requested destinations, aimed at minimizing shipping and distribution costs.

The effect of Al₂O₃ on physical & electrical properties of ZnO varistors

N. Riahi-Noori,A. Mehdikhani,A. M. Hadian,R. Sarraf-Mamoory 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.2

In this paper, the effect of Al₂O₃ on physical and electrical properties of ZnO varistors was investigated. After adding different amounts of Al₂O₃ to ZnO varistors, green and fired density and 3-point bending strength were measured. Also, microstructural analysis was evaluated by SEM. Finally, the optimum values for nonlinear coefficient (α) and breakdown voltage were obtained as 50 and 638 v/cm respectively. In this paper, the effect of Al₂O₃ on physical and electrical properties of ZnO varistors was investigated. After adding different amounts of Al₂O₃ to ZnO varistors, green and fired density and 3-point bending strength were measured. Also, microstructural analysis was evaluated by SEM. Finally, the optimum values for nonlinear coefficient (α) and breakdown voltage were obtained as 50 and 638 v/cm respectively.

Prevalence of burnout and related factors in nursing faculty members: a systematic review

Marziyeh Hosseini,Mitra Soltanian,Camellia Torabizadeh,Zahra Hadian Shirazi 한국보건의료인국가시험원 2022 보건의료교육평가 Vol.19 No.-

Purpose The current study aimed to identify the prevalence of burnout and related factors in nursing faculty members through a systematic review of the literature. Methods A comprehensive search of electronic databases, including Scopus, PubMed, Web of Science, Iranmedex, and Scientific Information Database was conducted via keywords extracted from Medical Subject Headings, including burnout and nursing faculty, for studies published from database inception to April 1, 2022. The quality of the included studies in this review was assessed using the appraisal tool for cross-sectional studies. Results A total of 2,551 nursing faculty members were enrolled in 11 studies. The mean score of burnout in nursing faculty members based on the Maslach Burnout Inventory (MBI) was 59.28 out of 132. The burnout score in this study was presented in 3 MBI subscales: emotional exhaustion, 21.24 (standard deviation [SD]=9.70) out of 54; depersonalization, 5.88 (SD=4.20) out of 30; and personal accomplishment, 32.16 (SD=6.45) out of 48. Several factors had significant relationships with burnout in nursing faculty members, including gender, level of education, hours of work, number of classroom, students taught, full-time work, job pressure, perceived stress, subjective well-being, marital status, job satisfaction, work setting satisfaction, workplace empowerment, collegial support, management style, fulfillment of self-expectation, communication style, humor, and academic position. Conclusion Overall, the mean burnout scores in nursing faculty members were moderate. Therefore, health policymakers and managers can reduce the likelihood of burnout in nursing faculty members by using psychosocial interventions and support.

Multi crack detection in helical gear teeth using transmission error ratio

Mohsen Rezaei,Mehrdad Poursina,Shahram Hadian Jazi,Farhad Haji Aboutalebi 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.3

Gear systems are used to transmit power in the industry when accuracy and synchrony are needed and helical gear systems are used in more accurate and high-speed industries. It is important to ensure that these systems work faultlessly, therefore the detection of the crack location and situation is very efficient in the gear systems. In this research, a new approach is proposed to detect the multi crack location and length in the helical gear teeth. To this end, after giving an explanation of helical gear mesh stiffness and demonstrating the helical gear pair dynamic modeling, the transmission error ratio method is used to detect the cracks locations and lengths. Then, according to solved examples, when the cracks locations are far enough that their effects on the transmission error are completely separated, the cracked teeth and the lengths of cracks can be detected exactly, and when the cracks are in adjacent teeth, according to the cracks lengths and depths and their effects overlap, the number of cracks and their lengths can be detected exactly, approximately or absolutely undetectable.