• Title/Summary/Keyword: Alpaca

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Internal Structure and Pigment Granules in Colored Alpaca Fibers

  • Wang Huimin;Liu Xin;Wang Xungai
    • Fibers and Polymers
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    • v.6 no.3
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    • pp.263-268
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    • 2005
  • Alpaca fibers have some distinct properties such as softness and warmth, which have not been fully understood in combination with the fiber internal structures. In the present investigation, the internal structures of alpaca fibers have been closely examined under the scanning electron microscope (SEM), especially in the longitudinal direction. The results showed that numerous pigment granules reside loosely inside pockets in brown and dark-brown alpaca fibers. These pigment granules were mainly distributed inside the cortical cells, the medullation regions as well as underneath the cuticles. Their size in the brown alpaca fibers was smaller and more uniformly round than in the dark-brown fibers. These granules in colored alpaca fibers loosen the bundle of cortical cells, providing many crannies in the fibers which may contribute to the superior flexibility, warmth and softness of the fibers. Moreover, there are no heavy metal elements found in the granules. The mordant hydrogen peroxide bleaching employed could eliminate the pigment granules and create many nano-volumes for further dyeing of fibers into more attractive colors.

Effects of Bleaching and Dyeing on the Quality of Alpaca Tops and Yarns

  • Liu, Xin;Wang, Lijing;Wang, Xungai
    • Fibers and Polymers
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    • v.5 no.2
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    • pp.128-133
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    • 2004
  • This paper reports the effects of bleaching of alpaca tops and dyeing of bleached alpaca tops/yarns on the quality of tops and yarns. A dark brown alpaca top was bleached with hydrogen peroxide. Two bleaching methods were tried for effectiveness of color removal. A portion of each bleached top was dyed after bleaching. Color parameters were examined for unbleached, bleached and bleached/dyed tops, these tops were then converted into yarns of different twist levels and counts using a worsted spinning system. Some of the bleached yarn from each bleaching method was dyed in a package dye vat to compare the difference of top dyeing versus yarn package dyeing on yarn quality. Fiber diameter, yarn strength, yarn evenness, yarn hairiness and fiber degradation were tested to examine the effects of bleaching and dyeing on these properties at top and yarn stages. A processing route for bleaching and dyeing alpaca fiber was recommended.

Comparative Analysis of Two Selective Bleaching Methods on Alpaca Fibers

  • Liu, Xin;Hurren, Christopher J.;Wang, Xungai
    • Fibers and Polymers
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    • v.4 no.3
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    • pp.124-128
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    • 2003
  • Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8% weight loss and 2.4% strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8% weight loss and 18% strength loss. BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellowness was reduced to 64.5 from 83.1 and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the premetallised dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results.

Study of Hair Melanins in Various Hair Color Alpaca (Lama Pacos)

  • Fan, Ruiwen;Yang, Gang;Dong, Changsheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.4
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    • pp.444-449
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    • 2010
  • The aim of this study was to measure the hair melanins of various colors and to find the relationship between the quantity of melanins and hair color phenotypes in alpacas. According to the Munsell color system, 3 healthy alpacas were selected for each of the 22 different hair color phenotypes (66 alpacas altogether). Alpaca hair was taken from the lateral thoracic region and then dissolved with different solutions to obtain melanins. The values of alkali-soluble melanins (ASM), eumelanin (EM) and pheomelanin (PM) were measured by spectrophotometric assay, and labeled as Sp.ASM, Sp.EM and Sp.PM, respectively. Data were analyzed using SPSS11.5 software. Results showed that average Sp.ASM and Sp.PM were increased as the color deepened from white to black, ranging from 0.500 to 4.543 for Sp.ASM and from 0.268 to 1.457 for Sp.EM. However, average Sp.PM had no such apparent relationship with color. Based on the value of Sp.ASM and EM, 7 hues were produced and gray was a single hue. Most of the data were in a normal distribution (p>0.10). ANOVA analysis showed that mean values of Sp.ASM, Sp.EM and Sp.PM were significantly different (p<0.05). The results also showed that Sp.ASM was positively correlated with Sp.EM but the correlation between Sp.ASM and Sp.PM was not significantly different from 0. It is concluded that EM is the major constituent of alpaca hair melanin; there is a significant correlation among ASM, EM and alpaca hair colors, and EM is the most reliable parameter for distinguishing these groups.

Frictional and Tensile Properties of Conducting Polymer Coated Wool and Alpaca Fibers

  • Wang Lijing;Lin Tong;Wang Xungai;Kaynak Akif
    • Fibers and Polymers
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    • v.6 no.3
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    • pp.259-262
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    • 2005
  • Wool and alpaca fibers were coated with polypyrrole by vapor-phase polymerisation method. The changes in frictional and tensile properties of the single fibers upon coating with the conductive polymer are presented. Coating a thin layer of polypyrrole on the alpaca and wool fibers results in a significant reduction in the fiber coefficient of friction, as the conducting polymer layer smooths the protruding edges of the fiber scales. It also reduces the directional friction effect of the fibers. Depending on the type of fiber, the coating may slightly enhance the tensile properties of the coated fibers.

Generating Sponsored Blog Texts through Fine-Tuning of Korean LLMs (한국어 언어모델 파인튜닝을 통한 협찬 블로그 텍스트 생성)

  • Bo Kyeong Kim;Jae Yeon Byun;Kyung-Ae Cha
    • Journal of Korea Society of Industrial Information Systems
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    • v.29 no.3
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    • pp.1-12
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    • 2024
  • In this paper, we fine-tuned KoAlpaca, a large-scale Korean language model, and implemented a blog text generation system utilizing it. Blogs on social media platforms are widely used as a marketing tool for businesses. We constructed training data of positive reviews through emotion analysis and refinement of collected sponsored blog texts and applied QLoRA for the lightweight training of KoAlpaca. QLoRA is a fine-tuning approach that significantly reduces the memory usage required for training, with experiments in an environment with a parameter size of 12.8B showing up to a 58.8% decrease in memory usage compared to LoRA. To evaluate the generative performance of the fine-tuned model, texts generated from 100 inputs not included in the training data produced on average more than twice the number of words compared to the pre-trained model, with texts of positive sentiment also appearing more than twice as often. In a survey conducted for qualitative evaluation of generative performance, responses indicated that the fine-tuned model's generated outputs were more relevant to the given topics on average 77.5% of the time. This demonstrates that the positive review generation language model for sponsored content in this paper can enhance the efficiency of time management for content creation and ensure consistent marketing effects. However, to reduce the generation of content that deviates from the category of positive reviews due to elements of the pre-trained model, we plan to proceed with fine-tuning using the augmentation of training data.

Analysis of User Reviews of Electric Kickboard Sharing Service Using Topic Modeling (토픽 모델링을 활용한 전동킥보드 공유 서비스의 사용자 리뷰 분석)

  • Jung Seung Lee
    • Journal of Information Technology Applications and Management
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    • v.31 no.1
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    • pp.163-175
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    • 2024
  • This study conducts topic modeling analysis on four electric scooter sharing platforms: Alpaca, SingSing, Kickgoing, and Beam. Using user review data, the study aims to identify key topics and issues associated with each platform, as well as uncover common themes across platforms. The analysis reveals that users primarily express concerns and preferences related to application usability, service mobility, and parking/accessibility. Additionally, each platform exhibits unique characteristics and challenges. Alpaca users generally appreciate convenience and enjoyment but express concerns about safety and service areas. SingSing faces issues with application functionality, while Kickgoing users encounter connectivity problems and device usability issues. Beam receives overall positive feedback, but users express dissatisfaction with application usability and parking. Based on these findings, scooter sharing service providers should focus on enhancing application features, stability, and expanding service coverage to meet user expectations and improve customer satisfaction. Furthermore, highlighting platform-specific strengths and providing tailored services can enhance competitiveness and foster continuous service growth and development.

Validation of Methods for Isolation and Culture of Alpaca Melanocytes: A Novel Tool for In vitro Studies of Mechanisms Controlling Coat Color

  • Bai, Rui;Sen, Aritro;Yu, Zhihui;Yang, Gang;Wang, Haidong;Fan, Ruiwen;Lv, Lihua;Lee, Kyung-Bon;Smith, George W;Dong, Changsheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.4
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    • pp.430-436
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    • 2010
  • The objective of the present studies was to develop and validate a system for isolation, purification and extended culture of pigment-producing cells in alpaca skin (melanocytes) responsible for coat color and to determine the effect of alpha melanocyte stimulating hormone treatment on mRNA expression for the melanocortin 1 receptor, a key gene involved in coat color regulation in other species. Skin punch biopsies were harvested from the dorsal region of 1-3 yr old alpacas and three different enzyme digestion methods were evaluated for effects on yield of viable cells and attachment in vitro. Greatest cell yields and attachment were obtained following dispersion with dispase II relative to trypsin and trypsin-EDTA treatment. Culture of cells in medium supplemented with basic fibroblast growth factor, bovine pituitary extract, hydrocortisone, insulin, 12-O-tetradecanolphorbol-13-acetate and cholera toxin yielded highly pure populations of melanocytes by passage 3 as confirmed by detection of tyrosinase activity and immunocytochemical localization of melanocyte markers including tyrosinase, S-100 and micropthalmia-associated transcription factor. Abundance of mRNA for tyrosinase, a key enzyme in melanocyte pigment production, was maintained through 10 passages showing preservation of melanocyte phenotypic characteristics with extended culture. To determine hormonal responsiveness of cultured melanocytes and investigate regulation of melanocortin 1 receptor expression, cultured melanocytes were treated with increasing concentrations of ${\alpha}$-melanocyte stimulating hormone. Treatment with ${\alpha}$-melanocyte stimulating hormone increased melanocortin receptor 1 mRNA in a dose dependent fashion. The results demonstrated culture of pure populations of alpaca melanocytes to 10 passages and illustrate the potential utility of such cells for studies of intrinsic and extrinsic regulation of genes controlling pigmentation and coat color in fiber-producing species.

A Proposal of Evaluation of Large Language Models Built Based on Research Data (연구데이터 관점에서 본 거대언어모델 품질 평가 기준 제언)

  • Na-eun Han;Sujeong Seo;Jung-ho Um
    • Journal of the Korean Society for information Management
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    • v.40 no.3
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    • pp.77-98
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    • 2023
  • Large Language Models (LLMs) are becoming the major trend in the natural language processing field. These models were built based on research data, but information such as types, limitations, and risks of using research data are unknown. This research would present how to analyze and evaluate the LLMs that were built with research data: LLaMA or LLaMA base models such as Alpaca of Stanford, Vicuna of the large model systems organization, and ChatGPT from OpenAI from the perspective of research data. This quality evaluation focuses on the validity, functionality, and reliability of Data Quality Management (DQM). Furthermore, we adopted the Holistic Evaluation of Language Models (HELM) to understand its evaluation criteria and then discussed its limitations. This study presents quality evaluation criteria for LLMs using research data and future development directions.

Proxy-Based Scalable Server Access Management Framework Using Reverse Webshell Protocol (웹쉘 기술을 통한 프록시 기반의 확장 가능한 서버 관리 프레임워크)

  • Daeun Kim;Sangwook Bae;Seongmin Kim;Eunyoung Jeong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.33 no.4
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    • pp.661-670
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    • 2023
  • With the emergence of serverless computing paradigm and the innovations of cloud technology, the structure of backend server infrastructure has evolved from on-premises to container-based serverless computing. However, an access control on the server still heavily relies on the traditional SSH protocol, which poses limitations in terms of security and scalability. This hampers user convenience and productivity in managing server infrastructure. A web shell is an interface that allows easy access to servers and execution of commands from any device with a web browser. While hackers often use it to exploit vulnerabilities in servers, we pay attention to the high portability of web shell technology for server management. This study proposes a novel proxy-based server management framework utilizing web shell technology. Our evaluation demonstrates that the proposed framework addresses the drawbacks of SSH without additional overhead, and efficiently operates large-scale infrastructures in diverse computing environments.