• Title/Summary/Keyword: internal bond

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Selected Properties of Particleboard Made from Sugar Palm (Arenga pinnata) Dregs

  • Faza AISYADEA;Greitta Kusuma DEWI;Ragil WIDYORINI
    • Journal of the Korean Wood Science and Technology
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    • v.51 no.5
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    • pp.334-344
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    • 2023
  • Dregs from the sugar palm (Arenga pinnata) starch industry are considered a waste product of the agricultural industry and have not yet been optimally utilized. Therefore, this study aimed to manufacture particleboards from dregs using different amounts of adhesive and particle size ratios. Sugar palm dregs, which had been separated into fibers and powder/fine particles, were used as raw material for making particleboards. The fiber had an average length of 6.84 ± 3.23 cm, while the fine particles were of a size that passed through size 10 mesh and remained in size 60 mesh. Three ratios of fiber to fine particles (100:0, 75:25, and 50:50 wt%) with three different amounts of sucrose-citric acid adhesive (10, 15, and 20 wt%) were used in this study. Increasing the amount of fine particles and the resin content can improve the physical properties and the internal bond strength of boards made from sugar palm dregs. The fine particles possibly filled the gap between the fibers in the particleboard, while the fibers exhibited a high bending strength. As a result, a high-performance particleboard can be attained by combining the composition ratio of fiber/fine particles and resin content. In this study, particleboards made from fiber/fine particles (75:25 wt%) and adhesive content of 15 wt% and 20 wt% had the mechanical properties that met the requirements of Japanese Industrial Standard (JIS) A 5908 type 18. Sugar palm dregs have the potential to be used as raw materials to create value-added particleboards.

The Chain Hotel Chef's Pygmalion Leadership for Effective Teamwork of Cooks (효과적인 팀워크를 위한 프랜차이즈 호텔 조리장의 피그말리온 리더십)

  • Koo, Dong-Woo;Lee, Sae-Mi;Jang, Hae-Jin
    • The Korean Journal of Franchise Management
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    • v.7 no.1
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    • pp.13-20
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    • 2016
  • Purpose - In the past, the chain hotel chefs only serve food to their customers. However recently, the hotel chefs play a pivotal role in hotel including considering various customer preferences, safety and nutrition of food, and increasing profits through effective human resource management and inventory control. With the change of the chain hotel chef's' roles, pygmalion leadership, one of new leadership styles, focuses on the effect that leader's positive expectation let subordinates have motivation and more engage in work. This study investigates the effect of chain hotel chef's pygmalion leadership on leader trust and organizational trust. Research design, data, and methodology - This study was to investigate the structural relationships among chain hotel restaurant chefs' pygmalion leadership, hotel restaurant cooks' leader trust, organizational trust, and teamwork, and how leader trust and organizational trust play mediating roles in the relationship between pygmalion leadership and teamwork. In this model, pygmalion leadership includes 4 dimensions: Climate, Feedback, Input, and Output. Data were collected using self-administered questionnaire survey on cooks of Deluxe hotel restaurants located in Seoul and Gyonggi-Do. The samples for data analyses were 243 excepting unusable responses. Result - The findings can be summarized as follows: First, climate and feedback had a positive effect on leader trust, respectively. Second, feedback and output had a statistically positive effect on organizational trust, respectively. Third, leader trust had positive effects on organizational trust and teamwork. Fourth, organizational trust had a significant effect on teamwork. Conclusions - As a chain hotel chef treats his/her staffs sincerely, they will be more engaged in work by establishing trust in their leader. Ultimately, it leads to higher sales profit and customer satisfaction. In addition, a hotel can encourage chefs and other staffs to treat each other as if the student-instructor relations, not just commanding staffs. Then, cooks build up their trust to their leader and organization for its sustained growth and development, and the internal bond in organization including teamwork is strengthened. Therefore, to strengthen teamwork and organizational trust, there should be active communication, knowledge sharing, goal sharing, and cooperation between chefs and cooks.

Does Brand Experience Affect Consumer's Emotional Attachments? (브랜드의 총체적 체험이 소비자-브랜드의 정서적 유대관계에 미치는 영향)

  • Lee, Jieun;Jeon, Jooeon;Yoon, Jaeyoung
    • Asia Marketing Journal
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    • v.12 no.2
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    • pp.53-81
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    • 2010
  • Brand experience has received much attention from considerable marketing research. When consumers consume and use brands, they are exposed to various specific brand-related stimuli. These brand-related stimuli include brand identity and brand communications(e.g., colors, shapes, designs, slogans, mascots, brand characters) components. Brakus, Schmitt, and Zarantonello(2009) conceptualized brand experience as subjective and internal consumer responses evoked by brand-related stimuli. They demonstrated that brand experience can be broken down into four dimensions(sensory, affective, intellectual, and behavioral). Because experiences result from stimulations and lead to pleasurable outcomes, we expect consumers to want to repeat theses experiences. That is, brand experiences, stored in consumer memory, should affect brand loyalty. Consumers with positive experiences should be more likely to buy a brand again and less likely to buy an alternative brand(Fournier 1998; Oliver 1997). Brand attachment, one of dimensions of the consumer-brand relationship, is defined as an emotional bond to the specific brand(Thomson, MacInnis, and Park 2005). Brand attachment is target-specific bond between the consumer and the specific brand. Thus, strong attachment is attended by a rich set of schema that link the brand to the consumer. Previous researches propose that brand attachments should affect consumers' commitment to the brand. Brand experience differs from affective construct such as brand attachment. Brand attachment is based on interaction between a consumer and the brand. In contrast, brand experience occurs whenever there is a direct and indirect interaction with the brand. Furthermore, brand experience is not an emotional relationship concept. Brakus et al.(2009) suggest that brand experience may result in brand attachment. This study aims to distinguish brand experience dimensions and investigate the effects of brand experience on brand attachment and brand commitment. We test research problems with data from 265 customers having brand experiences in various product categories by using multiple regression and structural equation model. The empirical results can be summarized as follows. First, the paths from affective, behavior, and intellectual experience to the brand attachment were found to be positively significant whereas the effect of sensory experience to brand attachment was not supported. In the consumer literature, sensory experiences for consumers are often equated with aesthetic pleasure. Over time, these pleasure experiences can affect consumer satisfaction. However, sensory pleasures are not linked to attachment such as consumers' strong emotional bond(i.e., hot affect). These empirical results confirms the results of previous studies. Second, brand attachment including passion and connection influences brand commitment positively but affection does not influence brand commitment. In marketing context, consumers with brand attachment have intention to have a willingness to stay with the relationship. The results also imply that consumers' emotional attachment is characterized by a set of brand experience dimensions and consumers who are emotionally attached to the brand are committed. The findings of this research contribute to develop differences between brand experience and brand attachment and to provide practical implications on the brand experience management. Recently, many brand managers have focused on short-term view. According to this study, we suggest that effective brand experience management requires taking a long-term view of marketing decisions.

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Study on the Factors Influencing the Investment Performance of Domestic Venture Capital Funds (국내 벤처펀드의 투자성과에 영향을 미치는 요인에 관한 연구)

  • InMo Yeo;HyeonJu Park;KwangYong Gim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.63-75
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    • 2023
  • This study conducted empirical analysis on the factors affecting the investment performance of 205 domestic venture funds (with a total liquidation amount of 7.25 trillion KRW) newly formed from 2007 to 2017 and completely liquidated as of the end of 2022. Due to the nature of private equity funds, obtaining empirical data is extremely challenging, especially for data post-COVID-19 era liquidations. Nevertheless, despite these challenges, it is meaningful to analyze the impact on the investment returns of domestic venture funds using the most recent data available from the past 10 years. This study categorized the factors influencing venture fund performance into external environmental factors and internal factors. External environmental factors included "economic cycles," "stock markets," "venture markets," and "exit markets," while internal factors included the fund management company's capabilities in terms of "experience," "professional personnel," and "assets under management (AUM)." The fund structure was also categorized into "fund size" and "fund length" for comparative analysis. In summary, the analysis yielded the following results: First, the 3-year government bond yield, which represents economic cycles well, was found to have a significant impact on fund performance. Second, the average 3-month KOSDAQ index return after fund formation had a statistically significant positive effect on fund performance. Third, the number of IPOs, indicating the competition intensity at the time of venture fund liquidation, was shown to have a negative effect on fund performance. Fourth, it was observed that the larger the AUM of the fund management company, the better the fund's returns. Finally, venture fund returns showed variations depending on the year of formation (Vintage). Therefore, when individuals consider investing in venture funds, it is considered a highly effective investment strategy to construct an investment portfolio taking into account not only external environmental factors and internal fund factors but also the vintage year.

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Quantitative Micro-CT Evaluation of Microleakage in Composite Resin Restorations (Micro-CT를 이용한 복합 레진 수복물 미세 누출도의 정량 분석)

  • Lee, Sang-Ik;Hyun, Hong-Keun;Kim, Young-Jae;Kim, Jung-Wook;Lee, Sang-Hoon;Kim, Chong-Chul;Hahn, Se-Hyun;Jang, Ki-Taeg
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.2
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    • pp.222-233
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    • 2007
  • One of the most important and basic test of dental restorative materials is the evaluation of microleakage into the tooth-restorative interface. There are many techniques to test microleakage, but most of them have several disadvantages. Recently developed microtomography(micro-CT) can provide the three dimensional image and information about the internal component in non-destructive way, therefore using micro-CT, it is possible to evaluate microleakage exactly in quantitative manner. The purpose of this study is to find a new method for quantitative and non-destructive evaluation of microleakage in composite resin restorations using micro-CT and to compare the new method with conventional dye penetration method. Thus, microleakages of two kinds of dentin bonding systems were evaluated with above two methods. 40 extracted sound human premolars were randomly divided into two groups consisting of 20 samples and restored accordingly. Group 1 : Class V resin restorations with $Adper^{TM}$ Singe Bond Group, 2 : Class V resin restorations with $Adper^{TM}\;Promp^{TM}$ L-pop. The $Filtek^{TM}$ Supreme was applied to the Class V cavities of all teeth. After that, 10 teeth from each group were applied to evaluation of microleakage using micro-CT, and other 10 teeth from each group were using conventional dye penetration method. The conclusions of this study were as follow : 1 Using micro-CT, Group 1 showed significantly less microleakage than Group 2 and there was statistically significant difference(p<0.01) between two groups. 2. Using conventional dye penetration method, Group 1 leaked less than Group 2 and there was statistically significant difference(p<0.01) between two groups 3. The difference between two groups is more evident in the method using micro-CT. 4. In all two methods, microleakage appeared more into the cavities to dentinal margins than enamel margins.

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The Crystal and Molecular Structure of Dipropargyldiphenylmethane (디프로파질디페닐메탄의 결정 및 분자구조)

  • Ahn Choong Tai;Choi Sam-Kwon
    • Journal of the Korean Chemical Society
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    • v.37 no.5
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    • pp.473-476
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    • 1993
  • Dipropargyldiphenylmetane, $C_{19}H_{16}, crystallizes in a monoclinic space group $C2/_c$$ with a = 11304(3), b = 20.799(5), c = 6.622(2)${\AA}$, ${\beta} = 112.8(3)^{\circ}$, Z = 4, V = 1435.3${\AA}^3,\;F(000)\;=\;520,\;D_c\;=\;1.14g{\cdot}cm^{-3}$ and ${\mu}\;=\;0.32\;cm^{-1}$. The structure was solved by direct methods and all non-H atoms were identified in the E-map. The final refinement gave R = 0.055 from 1328 unique observed reflections with I $\geq$ -1.0 $\sigma(I).$ The molecule belongs to the point group $C_2$ of Symmetry by possessing the 2-fold axis which coincides witeh the crystallographic symmetry axis in the unit cell. The linear propargyl moiety is nearly $perpendicular(94.2)^{\circ}$ to the molecular plane of the benzene ring. The internal angle of methane carbon atoms in $108.1(1)^{\circ}$, bonding to the benzene and the propargyl moiety with the bond lengths of 1.530(2) and $1.560(2)\AA$, respectively. The shortest contant between the molecules is $3.538(2)\AA$ between C(9) and C(9) (-x, y, -1/2-z).

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Fatigue Behavior of Prestressed Concrete Beams Using FRP Tendons (FRP 긴장재를 이용한 프리스트레스트 콘크리트 보의 피로 거동)

  • Kim, Kyoung-Nam;Park, Sang-Yeol;Kim, Chang-Hoon
    • Journal of the Korea Concrete Institute
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    • v.23 no.2
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    • pp.135-144
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    • 2011
  • Recently, researches about fiber reinforced polymer (FRP) which has excellent durability, corrosion resistance, and tensile strength as a substitution material to steel tendon have been actively pursued. This study is performed to examine FRP tendon used prestressed beam's safety under service load. The specimen was a prestressed concrete beam with internal bonded FRP tendon. In order to compare the member fatigue capacity, a control specimen of a prestressed concrete beam with ordinary steel tendon was tested. A fatigue load was applied at a load range of 60%, 70%, and 80% of the 40% ultimate load, which was obtained though a static test. The fatigue load was applied as a 1~3 Hz sine wave with 4 point loading setup. Fatigue load with maximum 1 million cycles was applied. The specimen applied with a load ranging between 40~60% did not show a fatigue failure until 1 million cycles. However, it was found that horizontal cracks in the direction of tendons were found and bond force between the tendon and concrete was degraded as the load cycles increased. This fatigue study showed that the prestressed concrete beam using FRP tendon was safe under a fatigue load within a service load range. Fatigue strength of the specimen with FRP and steel tendon after 1 million cycles was 69.2% and 59.8% of the prestressed concrete beam's static strength, respectively.

Infulence of Spacer and Degree of Esterification on Thermotropic Liquid Crystalline Properties of Amyloses Bearing Cholesteryl Group (스페이서와 에스터화도가 콜레스테릴 그룹을 지닌 아밀로오스들의 열방성 액정 특성에 미치는 영향)

  • Jeong, Seung-Yong;Ma, Yung-Dae
    • Polymer(Korea)
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    • v.31 no.4
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    • pp.356-367
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    • 2007
  • Three kinds of amylose derivatives such as: cholesteryloxycarbonated amyloses(CAMs) with degree of esterification(DE) ranging from 1.8 to 3, (6-cholesteryloxycarbonyl)pentanoated amyloses(PAMs) with DE ranging from 0.3 to 3, and fully cholesteryloxycarbonated PAMs(CPAMs) were synthesized, and their thermotropic liquid crystalline properties were investigated. CAMs with $DE{\geq}2.6$, PAM with DE=1.6 and all the CPAMs formed enantiotropic cholesteric phases, whereas PAM with $DE{\geq}2.2$ exhibited monotropic cholesteric phases. PAM with $DE{\geq}2.2$ and CPAMs with (6-cholesteryloxycarbonyl)pentanoyl DE (DS) more than 1.0 formed cholesteric phases with left-handed helical structures whose optical pitches (${\lambda}_{m'}s$) decrease with increasing temperature. However, the ${\lambda}_{m'}s$ of these samples decreased with increasing DS at the same temperature. On the other hand, CAMs, PAM with DE=1.6, and CPAM with DS=0.3 did not display reflection colors over the full cholesteric range, suggesting that the helicoidal twisting power of the cholesteryl group highly depends on the length of the spacer joining the cholesteryl group to the main chain and DS. The thermal stability and degree of order in the mesophase observed for the amylose derivatives highly depended on DE or DS. The results were discussed in terms of the difference ul the hydrogen bond, the internal plasticization, and the decoupling of the motion of side group with the main chain.

Morphological Changes of Hair Structure by UV Irradiation (자외선 조사에 의한 모발구조의 형태학적 변화)

  • Kim, Jung-Hoan;Lee, Ok-Sub;Han, Ji-Sook;Shin, Sung-Yeon;Baek, Doo-Hyun;Ha, Byung-Jo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.4
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    • pp.311-316
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    • 2008
  • In this study, we have investigated the effects of ultraviolet (UV) irradiation on the external and internal structure of human hair. For changes in morphological and chemical structure of UV-exposed hair, we utilized several microscopic techniques such as scanning electron microscope (SEM), transmission electron microscope (TEM), confocal laser scanning microscope (CLSM), and etc. The SEM showed the scales of UV-exposed hair appeared to be rough and bulkier because of chemical oxidation during UV irradiation. Small bulgy area of UV_exposed hair surface was appeared as a result of the decomposition in cysteic acid. In the TEM picture the UV-exposed hair showed the cleaved aperture of hair and destruction of melanin granules. Three dimensional topographical images were obtained by using CLSM. In the optical single section, high fluorescent intensity appeared in virgin hair. In the case of UV-exposed hair, low fluorescence intensity appeared. This means the aromatic amino acids in virgin hair were more abundant than UV-exposed hair.

Difference of the Chemical Compositions Between Petroleum Ether Extract and its Tall Oil in Pitch Pine, Pinus Rigida Mill (리기다소나무재(材)의 유기용매(有機溶媒) 추출물(抽出物)과 그 tall oil 간의 조성(組成)의 차이(差異))

  • Ko, Sang-Woon;Ahn, Won-Yung
    • Journal of the Korean Wood Science and Technology
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    • v.16 no.2
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    • pp.79-89
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    • 1988
  • This experiment was carried out to investigate the difference of compositions between petroleum ether extract and its tall oil in Pinus rigida Mill. xylem and to obtain the basic data on effective extraction and its utilization of by-product, resin and fatty acid, when pulp making. After both petroleum ether extract from wood meal and its tall oil in pitch pine were separated to the resin and fatty acid by using DEAE-Sephadex and aluminum oxide column, these were analyzed with gas chromatograph. The results obtained were as follows: 1. Fatty acids contained as ester form in living trees were varied by peroxide of organic solvent in petroleum ehter extraction and cooking chemicals in cooking. 2. Pimaric-type acid was eluted earlier than abietic-type acid in resin acids and the fewer the carbons, the earlier the elution in fatty acids. 3. The retention time of SE-30 column was even smaller than that of OV-101 column but the relative retention time obtained by using methyl pimarate and methyl stearate as internal standard was nearly identical. 4. Both petroleum ether extract and tall oil mainly consisted of resin acids, expecially abietic-type acid. 5. Tall oil had more fatty acid but less resin acid than petroleum ether extract. Also, the content of unidentified materials was increased owing to the isomerization and the shift of double bond position in unsaturated fatty acids by high temperature and cooking chemicals when cooking.

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