Laser Beam as a Precision Tool to Increase Fatigue Resistance in an Eyelet of Undercarriage Drag Strut

Marek Szkodo,Anna Bień,Alicja Stanisławska 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.1

The article contains the results of tests on a laser-processed eyelet of undercarriage drag strut to increase its fatigue strength. Laser processing concentrated on both sides around the hole of eye for connecting the undercarriage drag strut caused that the material in this area withstood more than twice the number of load cycles established for this material. In order to determine the reasons for the increase in fatigue strength, residual stresses in laser-treated LT areas and in the base metal BM located between melted paths were determined, using the nanoindentation test and Williamson Hall method. The modified Williamson Hall analysis of XRD patterns was also used to determine the dislocation density in both areas. The results indicate that high residual tensile stresses occur in melted areas and in base metal located between melted paths occur high residual compressive stresses. A large increase in hardness and elastic properties, dissolution of non-metallic inclusions, as well as large solid solution and sub-grain strengthening contributed to the high fatigue resistance of the melted areas.

Effect of crude fibre additives ARBOCEL and VITACEL on the physicochemical properties of granulated feed mixtures for broiler chickens

Urban Jakub,Michalczuk Monika,Batorska Martyna,Marzec Agata,Jaroszek Adriana,Bień Damian 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.2

Objective: The aim of the study was to evaluate the physicochemical properties (nutrient composition, pH, water content and activity, sorption properties) and mechanical properties (compression force and energy) of granulated feed mixtures with various inclusion levels of crude fibre concentrates ARBOCEL and VITACEL for broiler chickens, i.e. +0.0% (control group - group C), +0.3%, +0.8%, +1.0%, +1.2%. Methods: The feed mixtures were analyzed for their physicochemical properties (nutrient composition by near-infrared spectroscopy, pH with the use a CP-401 pH meter with an IJ-44C glass electrode, water content was determined with the drying method and activity was determined with the Aqua Lab Series 3, sorption properties was determined with the static method) and mechanical properties (compression force and energy with the use TAHD plus texture analyzer). The Guggenheim-Anderson-de Boer (GAB) model applied in the study correctly described the sorption properties of the analyzed feed mixtures in terms of water activity. Results: The fibre concentrate type affected the specific surface area of the adsorbent and equilibrium water content in the GAB monolayer (p≤0.05) (significantly statistical). The type and dose of the fibre concentrate influenced the dimensionless C and k parameters of the GAB model related to the properties of the monolayer and multilayers, respectively (p≤0.05). They also affected the pH value of the analyzed feed mixtures (p≤0.05). In addition, crude fibre type influenced water activity (p≤0.05) as well as compression energy (J) and compression force (N) (p≤0.001) (highly significantly statistical) of the feed mixtures. Conclusion: The physicochemical analyses of feed mixtures with various inclusion levels (0.3%, 0.8%, 1.0%, 1.2%) of crude fiber concentrates ARBOCEL or VITACEL demonstrated that both crude fiber types may be used in the feed industry as a feedstuff material to produce starter type mixtures for broiler chickens.

Morphology Evolution of Mn5Si3 Phase and Effect of Mn content on Wear Resistance of Special Brass

Lifu Bie,Xiaohong Chen,Ping Liu,Tao Zhang,Xiangliu Xu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.4

There is a surge of interests in developing newer materials with special properties and many areas are being explored byseveral groups. We wish to report our findings on the effect of Mn content on the microstructure and tribological behaviorof special brass. With the increase of Mn content in the range of 4–10 wt%, the hardness and wear resistance of the specialbrass were all changed, and the adhesion with abrasion is form the friction behavior, mainly for all brasses. It was observedthat the matrix grain size was the smallest, and the hard phase was precipitated the most when the Mn quantity attained the8 wt% mark. During this period, the brass has the highest hardness and best wear resistance, which results from the grainrefinement and load transferring effect of precipitates. It was characterized by SEM, EDS, XRD, TEM, etc., and the resultsconfirmed that the precipitates were Mn5Si3and its structure was hollow hexagonal prism. The morphology evolution of thehard phase and its growth mechanism have been investigated, analyzed and simulated the nucleation and growth process ofthe Mn5Si3phase based on crystallography. The outcomes also showed that the presence of defects on the {0001} faces wasthe crucial factor for one-dimensional elongated structure of Mn5Si3phase.

An Empirical Analysis of Android Apps Bug and Automated Testing Approach for Android Apps

Yi Bie,Sheng Bin,Gengxin Sun,Xicheng Zhou 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.9

Android platforms and its applications (apps) have gained tremendous popularity recently, hence the reliability of Android apps is becoming increasingly important. Due to the novelty of the Android platform, apps are prone to errors, which would affect user experience and requires frequent bug fixes. In this paper, an empirical study on bugs in some widely-used open-source Android apps from diverse categories such as media, tools and communication were performed. Based on the findings of the empirical study, an approach for automating the testing process for detecting Android apps GUI bugs was presented. We show how the approach helped to re-discover existing bugs and find new bugs, and how it could be used to prevent certain bug categories. Our empirical study and automated testing approach have the potential to help developers increase the quality of Android apps.

Research on fault diagnosis method of reciprocating compressor valve based on IVMD-CMS model

Fengfeng Bie,Suzhen Chen,Fengxia Lyu,Hongfei Zhu,Qianqian Li,Xinting Miao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.8

As for the complex shock vibration characteristics, the issue of difficult to extract the characteristic information of reciprocating compressor valve, a fault diagnosis method combining informational variational mode decomposition (IVMD) and cyclic modulation spectrum (CMS) is proposed. In this paper, the Bayesian information criterion (BIC) is optimized for the VMD decomposition parameter firstly, and the obtained IVMD algorithm is applied to decompose the signal into intrinsic mode functions (IMFs). Secondly, the signal is reconstructed with the correlation coefficient. Finally, the CMS algorithm is utilized for the reconstructed signal analysis, from which main spectral features of the carrier frequency and cyclic frequency on the cyclic modulation spectrum are obtained. The characteristic information of the signal is highlighted with the amplitude and relationship of the frequency feature. The effectiveness and superiority of the method in the diagnosis of reciprocating compressor valve faults are demonstrated with the numerical simulation and experimental analysis.

Static Hand Gesture Recognition Method Based on Depth Images with Shape Context Feature

Mei Bie,Zhe Wang 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.7

Static hand gesture recognition is very important for human-computer interaction systems, which is widely used in human-computer interaction systems. Using visible RGB images as the input method would be more stable, but the illumination and skin color are big problems; by contrast the depth images is a better choice. A novel algorithm which recognizes static hand gesture based on depth images using 3d shape context feature and improves the performance by arm major axis correction and contour-center sampling is proposed. Arm major axis correction can solve the rotation problem and the sampling, which increases the recognition rate. Besides, using 3d space information makes the algorithm more stable. Experimental results show that the average recognition rate gets to 95.8%, and the performance and speed are superior to existing algorithms. Recognition results can be widely used in the follow-on real scene human-computer interaction (HCI) operations.

Frequency Hopping CR MAC Protocol in Cognitive Radio Ad Hoc Network

Mei Bie,Zhe Wang,Wei Xiao,Kai Song 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.9

To insure the fairness for the Cognitive Radio (CR) nodes with various available channels, a frequency hopping CR MAC protocol based dynamic (named DCR-MAC) is proposed. In the case of uneven distribution of frequency spectrum in cognitive Ad Hoc network, based on the numbers of workable channels of each cognitive node, DCR-MAC protocol adjusts access time dynamically, ensuring the node priority access channel number, in order to improve the overall performance of the network. Meanwhile, against the problem of the multi-channel hidden terminal which appears in cognitive network of single wireless interface configuration, through introducing the "data segment" mechanism, and informing present channels occupied condition of adjacent node via receiving node, DCR-MAC protocol broadcast of channel occupation in transmission channel, and prohibit possible data transmission of adjacent node, in order to solve this problem on this account. Finally, proving that DCR-MAC protocol is obviously excelled other FH CR MAC protocols in through put capacity, packet access delay, accessing fairness which through network simulation.

Inheritance of Resistance to Puccinia Coronata Var Avenae in Six Selections of Avena Steri is

Kim, Heung Bie 東國大學校 學徒護國團 農林大學大隊 1976 東國農林 Vol.9 No.-

Six selections of Avena sterilis, introduced from Israel as sources of resistance to oat crown rust, were crossed with susceptible A. bywantina 'frazier'. The number of genes conditioning resistance to culture H-14 of race 326 of Puccinia coronata var. avenae in each of the six selections was determined from studies of F_1, F_2 and F_3 populations from the crosses. P.I.287211, P.I.295919 and P.I.296244 each appeared to have a single dominant gene for resistance, and P.I.296265 and P.I.296266 each two dominant ones. C.I.8295 had a single partially dominant gene for resistance. Crosses among the A.sterilis parents indicated that at least four different genes conditioned resistance to culture H-14. Association between F_2 reaction to crown rust and morphalogical characters of the spikelet was determined with the x^2 test for independence. In four crosses, all spikelet characters appeared to be independent of rust reaction. In Frazier × P.I.296244, basal pubescence of the lemma on the secondary floret appeared to be associated with reaction to crown rust. Strong association between reaction to crown rust and lemma pubescence on the primary floret was evident in Frazier × P.I.296265.

近代の文學作品に現れた漢字表記のオノマトペ

신정이혜 ( Arai Bie ) 韓國日語日文學會 2009 日語日文學硏究 Vol.69 No.1

알코올 내성 젖산균 Pediococcus acidilactici K3와 S1의 분리 및 생리적 특성

장단비 ( Dan Bie Jang ),박슬기 ( Seul Ki Park ),이현주 ( Hyun Joo Lee ),표상은 ( Sang Eun Pyo ),이한승 ( Han Seung Lee ) 한국미생물생명공학회(구 한국산업미생물학회) 2013 한국미생물·생명공학회지 Vol.41 No.4

김치, 막걸리 및 시판되는 누룩으로부터 젖산균을 분리한 후 다양한 농도의 알코올을 함유한 MRS 배지에서 배양하여 생육 여부를 조사하였다. 알코올이 13%(v/v) 포함된 MRS 배지에서 OD600 값이 가장 높이 증가한 젖산균 2종을 최종 선별하였고 이 두 균주의 16S rRNA 유전자 염기서열분석 및 API kit를 이용한 생화학적 동정을 실시한 결과 두 종 모두 P. acidilactici에 가까운 종인 것을 확인하여 P. acidilactici K3와 P. acidilactici S1으로 명명하였다. 선별한 P. acidilactici K3와 S1의 bacteriocin 생성 여부를 확인한 결과 식중독균인 S. aureus의 생육 저해를 일으키는 bacteriocin 생성 능력이 있음을 확인하였다. 선별한 두 균주와 표준 균주(P. acidilactici DSM 20284)의 알코올 내성을 비교한 결과 6% 이하의 저농도 알코올이 포함된 배지에서는 균주 생육에 큰 차이가 없었으나 12% 이상의 알코올이 포함된 배지에서는 표준 균주보다 최대 3배 이상 알코올 내성이 뛰어남을 확인 하였다. 알코올 내성 균주 P. acidilactici K3와 S1을 살균 막걸리에 첨가한 후 냉장 온도(4oC와 10oC)에서 저장하며 생균수를 측정한 결과 사멸하지 않고 한 달 간 생균수가 유지됨을 확인하였다. Lactic acid bacteria (LAB) are a representative group of probiotics and used in many fermented foods and beverages. Several recent studies have shown that LAB are present in makgeolli which is a traditional Korean alcoholic beverage. However, most LAB are intolerant of more than 6% (v/v) alcohol concentrations. For this reason, alcohol-tolerant LAB are isolated from kimchi, makgeolli and nuruk using alcohol containing selective media. After being cultured in MRS broth containing 13% (v/v) alcohol, the two strains which showed the highest increasing O.D values, were finally selected. As results of 16S rRNA gene sequencing and biochemical characterization using an API kit, the two species were identified as Pediococcus acidilactici K3 and S1. In addition, the identified two strains produced bacteriocins against Staphylococcus aureus. When compared with the P. acidilactici type strain, the two selected strains possessed two to three time higher growth on 12-13% (v/v) alcohol containing MRS broth. The viability of P. acidilactici K3 and S1 when inoculated in makgeolli and stored at 10oC did not decrease through a period of one month indicating that the selected strains can be used for LAB containing makgeolli.