• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.4
• /
• pp.623-633
• /
• 2020

Objective: Substituting starch with digestible fiber (dF) can improve digestive health of rabbits and reduce costs. Therefore, it is necessary to develop a criterion for dF and starch supply. Effects of the dietary dF-to-starch ratio on pellet quality, growth and cecal microbiota of Angora rabbits were evaluated. Methods: Five isoenergetic and isoproteic diets with increasing dF/starch ratios (0.59, 0.66, 0.71, 1.05, and 1.44) were formulated. A total of 120 Angora rabbits with an average live weight of 2.19 kg were randomly divided into five groups with four replicates. At the end of 40 day feeding trial, cecal digesta were collected to analyse microbiota. Results: The results showed that the dF/starch ratio had linear effects on pellet variables (p<0.01). When the dF/starch ratio was 1.44, the pellets had the lowest powder and highest durability. The dF/starch ratio had unfavorable linear effects on growth variables (p<0.001). When analyzed by quadratic regression, the optimal dF/starch ratios for average weight gain and feed/gain were 0.59 and 0.74, respectively. There were differences in wool yield, fiber length and fiber diameter caused by the dF/starch ratio (p<0.05), and the dF/starch ratios that ranged from 0.66 to 1.06 were appropriate for good results. The cecal microbiota operational taxonomic unit (OTU) number index in the 1.05 dF/starch treatment was higher than that in the 0.66 and 0.71 dF/starch treatments. The higher dF/starch ratio resulted in a higher cecal microbiota OTU number index (p<0.05). The proportion of Ruminococcus in the 0.71 dF/starch treatment was higher than that in the 0.59 dF/starch treatment (p<0.05) Conclusion: The most suitable dF/starch ratio for feed pellet quality is 1.44, and for rabbit growth the optimal range of ratios is from 0.59 to 0.74. With combination of the wool growth, output cost, and cecal microbiota, we suggest that a dietary dF/starch ratio ranging from 0.74 to 1.06 is optimal.

• Journal of Korean Institute of Industrial Engineers
• /
• v.10 no.1
• /
• pp.37-40
• /
• 1984

A model for the weight distribution of pellet sizes of carbon black products is proposed so that it may be utilized in establishing the product standard and a quality control scheme. The various grades of carbon black products from the Korea Steel Chemical Co., Ltd. are examined to validate the adequacy of the proposed model.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.4
• /
• pp.346-357
• /
• 2013

In this study, it was conducted to produce wood pellets using domestic forest thinning residues and examine their quality according to Korean pellet quality standard. Raw materials were composed of larch and mixed broad leaves species. Based on the small-end diameter (6 cm), they were classified into four different types of raw materials such as LM (larch with middle diameter), LS (larch with small diameter), MM (mixed broadleaf with middle diameter), and MS (mixed broadleaf with small diameter). After crushing and drying process, wood pellets were produced by a ring-die type pelletizer using each raw material. Wood pellets made from four different types of raw materials were tested for their quality such as calorific value, moisture content, ash content, inorganic matters and so on. As results of quality analysis, the calorific values of all wood pellets were higher than 198 kcal/kg, and satisfied with the first grade of Korea wood pellet standard. The ash content was slightly increased after pelletizing. Mechanical durability of wood pellets was highly dependent on the types of raw materials. The quality differences among wood pellets were turned out due to different physical and chemical characteristics of raw materials even though the same pelletizing condition was applied.

• Journal of the Korean Wood Science and Technology
• /
• v.51 no.5
• /
• pp.381-391
• /
• 2023

Densification is a technique used to improve biomass quality in wood pellet manufacturing and torrefaction treatment. In this study, the effects of torrefaction on the quality of Calliandra wood pellets were investigated, and pellets of Calliandra wood (Calliandra calothyrsus) and bark were evaluated. The study was conducted using a completely randomized design with two treatment factors, namely torrefaction temperature (250℃ and 300℃) and torrefaction duration (30, 45, and 60 min). The results showed that the interaction between temperature and torrefaction duration significantly affected the compressive strength, proximate value, and calorific value of the torrefied Calliandra wood pellets. An increase in the temperature and torrefaction duration decreased the compressive strength, moisture content, volatile matter content, and ash content of the torrefied Calliandra wood pellets. Conversely, the calorific value of Calliandra wood pellets increased with increasing temperature and torrefaction duration. The best-quality Calliandra wood pellets were produced at a torrefaction temperature and duration of 300℃ and 60 min, respectively. In terms of important quality parameters, ash content of 0.90% and calorific value of 6,303.80 cal/g were observed, which complied with the quality standards of Indonesian National Standard 8675:2018 and Deutsche Industrie Norm 51731.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.6
• /
• pp.96-102
• /
• 2000

The finishing process for dies and molds is an important process because it has influence on final quality of products. And it is difficult to automatize finishing process so that the process has depended on expert's skill until now. However, recently a study on development of die automatic finishing machine has been progressed, and actually this machine is applied to fabrication of die. But the research about tooling system is not enough and finishing tool must have high machining efficiency and adaptability of curved surface. So, this study investigated the application of conductive elastic tool which is composed of metal-resin bonded pellet and elastic backing material. The metal-resin bonded pellet is used to finish the surface by conventional mechanical grinding or electro-chemial grinding method. And elastic backing material is used to follow the curved surface. So conductive elastic tool has long lifetime, uniform removal rate and adaptability of curved surface.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.3 s.96
• /
• pp.84-90
• /
• 1999

The finishing process for dies and molds is directly related to finished surface quality, but many parts of process depend on human labor which needs much time and value. So automatic finishing machine has been produced for dies and molds, and applied widely for finishing process. Conventionally finishing machine has applied resin bonded finishing pad as a tool, but the removal ability of pad decreases greatly as finishing process goes on. In the finishing mechanism for dies and molds, finishing process is affected severely by cutting process, so can be divided into removing cusp and smoothing surface process. So, this study investigated the application of cast iron bonded diamond pellet for press dies, which is considered to have better characteristics than the other metal bonded pellets. The finishing characteristics were compared the between finishing pellet and pad. And finishing performance was appraised as the several cutting surfaces.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.46 no.3
• /
• pp.282-286
• /
• 2013

This study was conducted to compare extruded pellets (EP) and soft extruded pellets (SEP) with a raw fish-based moist pellet (MP) diet on the growth and flesh quality of Korean rockfish Sebastes schlegeli. Three groups of 20,000 fish (initial mean weight 133 g) per net-cage ($6{\times}12{\times}7m$) were fed commercial EP, SEP or MP for 16 months. The survival of fish fed SEP was higher than those of fish fed EP or MP. The highest growth performances were observed in the mean weight gain, total weight gain, and feed efficiency of fish fed MP, followed by those fed EP and SEP. Among the fish fed on extruded pellets, the total weight gain of fish fed SEP was higher than that of those fed EP, while fish fed EP grew faster than those fed SEP. No notable differences in body composition, sensory scores or textural properties of the dorsal muscle were observed in fish fed on EP, SEP or MP. Thus, it is suggested that extruded pellets, rather than raw fish-based moist pellets, could be fed to Korean rockfish without compromising flesh quality.

• Korean Journal of Adult Nursing
• /
• v.20 no.1
• /
• pp.21-32
• /
• 2008

Purpose: This study was to identify the effects of the hand acupressure therapy on sleep quality and mood state of adults having insomnia. Methods: The study was a one group pretest-posttest design. The subjects for this study were 15 insomniac adults. All the subjects were assessed for their sleep quality and mood state using PSQI(Pittsburgh Sleep Quality Index) and POMS(Profile of Mood States). The pellet stimulating hand acupressure therapy was applied using New Seoam Press Pellets 1 Ho for 4 weeks. Data were analyzed by the SPSS 12.0 version program with descriptive statistics and wilcoxon signed-rank test. Results: The mean total score of PSQI was 6.67 and the POMS was 6.68. There were significant decreases in subject's total PSQI score(p=.000) and in total POMS score(p=.008) after the therapy. Conclusion: These results suggest that pellet stimulating hand acupressure therapy is effective for sleep quality and mood state of adults having insomnia.

• Asian-Australasian Journal of Animal Sciences
• /
• v.11 no.5
• /
• pp.597-607
• /
• 1998

Processing is generally employed to alter the physical and chemical properties of feeds used in pig diets, using hammer/roller mills, pellet mills and extruders/expanders. The reported optimum particle sizes of corn are approximately $500{\mu}m$, $500-700{\mu}m$, $400-600{\mu}m$, for nursery, growing-finishing, and breeder pigs respectively. Optimum particle size of grains are affected by diet complexity. There was a trend towards reducing particle size in order to increase ADG in pigs fed a simple diet, though such was not the case for pigs fed a complex diet. Uniformity of particle size also affects the nutritional values of swine feeds. Uniform particle sizes would consistently give greater nutrient digestibilities. In terms of pellet quality, it is reported that a higher incidence of fmes in pelleted feeds has a direct correlation with poorer feed conversion ratio in pigs. Particle and pellet sizes are also very important for pelleting in terms of grinding, digestibility, stomach ulceration and pellet durability. A particle size of $600{\mu}m$, or slightly less, seemed optimal for com in fmishing pigs, and the 5/32 in. diameter pellets supported the best efficiencies of gain during nursery and finishing phases. Extruder and/or expander processes would allow the feed industry an increased flexibility to utilize a wider spectrum of feed ingredients, and improve pellet quality of finished feeds. It would appear that extruded or expanded diets containing highly digestible ingredients have little effect on the growth performance of pigs, and the feeding values of the feeds over pelleted diets were not improved as pigs grew. The extruder or expander is much more effective than a pelletizer in salmonella control. Gastric ulcerations and/or keratinizations were consistently reported in pigs fed mash and processed diets containing finely ground grains, whereas carcass quality was not affected by diet processing methods such as pelleting, extruding or expanding. In corn- or sorghum-based diets, the electrical energy consumption is 4-5 times higher in the expanding than in the pelleting process. But the expander's processing cost was half of that shown by an extruder. Finally, the decision of which feed processing technology to adopt would depend on the processing cost, and any potential improvement in growth performance and digestibilities of nutrients should offset the increased operating and capital costs related to the extruder/expander technology over mash or pelleting processes in pigs.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.6
• /
• pp.818-823
• /
• 2014

This study compared the effects of feeding diets consisting of an experimental extruded pellet with tapioca starch (EEP), commercial extruded pellet (CEP), and raw-fish-based pellet (MP) on the growth, flesh quality, and apparent digestibility coefficient of the olive flounder Paralichthys olivaceus. Two replicated groups of 4,000 fish each (initial mean weight: $81.8{\pm}3.5g$) were fed one of the experimental diets for 5 months. After the feeding trial, the final mean weight, weight gain, specific growth rate, and feed efficiency of fish fed the EEP was significantly higher than those of fish fed the CEP and MP. Moisture content in the whole-body of fish fed MP was significantly higher than those of fish fed other diets. However, the highest crude protein in the whole-body was found in fish groups fed the EEP. Significantly higher contents of 24:1n-9, 20:5n-3, 22:6n-3 and lower 18:1n-7 was observed in fish fed the EEP compared with fish fed the MP. The amino acid contents in the whole-body showed significant differences in the composition depending on the feed, but the distribution of free amino acids showed similar patterns. Among amino acids, glutamic acid showed the highest content in all the experimental groups, and the threonine, cysteine, and lysine contents were significantly higher in the groups fed with EEP and CEP than in the group fed with MP. Digestibility of nutrients of the EEP was significantly higher than that of fish fed the CEP. This suggests that extruded pellets can be used to feed olive flounder without compromising growth and flesh quality in comparison to raw-fish-based moist pellets. Formulation of the EEP could be used as a practical feed for olive flounder.