• Journal of Sericultural and Entomological Science
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• no.12
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• pp.37-45
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• 1970

The processing management forms of our country's filature factories in 1969 are summarized as follows. (1) About 80％ of total cocoon collection is made within 5 days involving peak day, and 10％ of cocoon collection is finished until 3 days before and after the peak day, (2) About 92％ of alive cocoons transported on unpaved road, and about 40％ of the cocoons purchased by all factories are loaded on trucks from common selling station which is far beyond 40km, therefore a new packing system of alive cocoons to drop the damage of cocoon qualities, should be taken. (3) 22％ of all factories in our. country have only low-temperature cocoon drying machine. Therefore the installment of hot-air cocoon drying machine is required urgently. (4) In view of cocoon qualities in our country, the grouping method of cocoon for reeling. taken by about 50％ of the factories at percent, which classify cocoons for reeling as high group (1,2,3,4 grades) and low group(5,6 grades), will have to be replaced by the method tat classify them high group (1,2 grades) middle group (3,4 grades), low group (5,6 grades). (5) The .ratio of cocoon assorting stood about 10％ in multi-ends reeling, about 15％ in automatic reeling, conclusively, the ratio of cocoon assorting for automatic reeling was higher tan that for multi-ends reeling. One person's ability for a day in cocoon assorting reaches to about 80-100kg. (6) Cocoon cooking condition requires the increase of the cooking time, the pressure and temperature used to be prolonged as much as the qualities of cocoons are material cocoon ior automatic and double cocoon machines are treated uncompletely. (7) Automatic silk reeling is being performed at 1-2$^{\circ}C$ lower in reeling water temperature and operated at about twice velocity. (8) The temperature and humidity of rereeling room stood at 25$^{\circ}C$, 67.2％ R.H and 32.3$^{\circ}C$, 51.9％ R.H of rereeling machine are showed, Average rereeling velocity is 233m/min and large reefs charged for one person are 7.5 reels and form of skein used in all factories is double skein. (9) About 73％ of water sources for filature used under-earth water. About 48％ of all filature factories in our country have not yet water purifying equipments. Installation of the equipment for these factories seems to be urgent, (10) Denier .balance, sizing reel, seriplane, are being used in most factories as self-inspection apparatus. (11) More than 90％ of the factories use the vacum tank in rereeling process and about 20％ of them use it in cocoon cooing process (12) Only 21％ of the factories use chemicals in filature process. About all them use "Seracol 100" in cocoon cooking process and "Seracol 500" in rereeling process, (13) Above survey results explain each all factories show large difference in the processing management. Therefore, it is believed that intercommunication through seminar or technical exchange will contribute to the production evaluation of cocoon in our filature industry.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.7-16
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• 1994

This study was designed to establish the relationship between airborne trichloroethylene concentrations and total trichloro-compounds and trichloroacetic acid in urine samples of the trichloroethylene exposed workers, to examine if the biological screening value for trichloroacetic acid in urine set by the Ministry of Labor is appropriate, and to suggest a suitable biological screening value for total trichloro-compounds in urine. Seventy male workers from the cleaning, the packing, and the inspcetion areas were selected as the study group and eighty male office workers were chosen as the control group. The results were as follows: 1. The mean values of total trichloro-compounds and trichloroacetic acid in the exposed group ($48.1{\pm}1.5mg/{\ell}$, $19.7{\pm}1.9mg/{\ell}$) were significantly higher than those in the control group($4.3{\pm}1.5mg/{\ell}$, $1.8{\pm}1.2mg/{\ell}$). 2. The airborne tichloroethylene concentrations were significantly related with the concentrations of total trichloro-compounds in urine(r=0.8212) and the concentrations of trichloroacetic acid in urine(r=0.7216). 3. The average trichloroethylene concentrations in the manual cleaning plants and that in the automatic cleaning plants were 40.1 ppm and 7.7 ppm, respectively. The difference between two groups was statistically significant. 4. The geometric mean of 49.6 ppm trichloroethylene concentration was resulted in the $185.4mg/{\ell}$ total trichloro-compounds in urine, and the 50 ppm trichloroethylene concentration was expected to produce $170.4{\pm}28.5mg/{\ell}$ total trichloro-compounds in urine. 5. With the geometric mean of 49.6 ppm trichloroethylene concentration, the corresponding geometric mean concentration of trichloroacetic acid in urine was $74.7mg/{\ell}$. In conclusion, the level of personal exposure to trichloroethylene concentration was significantly correlated with the concentrations of total trichloro-compounds and trichloroacetic acid in urine. Current biological screening value of $75mg/{\ell}$ for trichloroacetic acid in urine set by the Ministry of Labor was thought to be appropriate, and a biological screening value for total trichloro-compounds in urine should be set in the range of $170.4{\pm}28.5mg/{\ell}$ as a reference value for trichoroethylene exposure.

• Progress in Medical Physics
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• v.16 no.1
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• pp.24-31
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• 2005

The stereotactic radiosurgery (SRS) describes a method of delivering a high dose of radiation to a small tar-get volume in the brain, generally in a single fraction, while the dose delivered to the surrounding normal tissue should be minimized. To perform automatic plan of the SRS, a new method of multi-isocenter/shot linear accelerator (linac) and gamma knife (GK) radiosurgery treatment plan was developed, based on a physical lattice structure in target. The optimal radiosurgical plan had been constructed by many beam parameters in a linear accelerator or gamma knife-based radiation therapy. In this work, an isocenter/shot was modeled as a sphere, which is equal to the circular collimator/helmet hole size because the dimension of the 50% isodose level in the dose profile is similar to its size. In a computer-aided system, it accomplished first an automatic arrangement of multi-isocenter/shot considering two parameters such as positions and collimator/helmet sizes for each isocenter/shot. Simultaneously, an irregularly shaped target was approximated by cubic structures through computation of voxel units. The treatment planning method by the technique was evaluated as a dose distribution by dose volume histograms, dose conformity, and dose homogeneity to targets. For irregularly shaped targets, the new method performed optimal multi-isocenter packing, and it only took a few seconds in a computer-aided system. The targets were included in a more than 50% isodose curve. The dose conformity was ordinarily acceptable levels and the dose homogeneity was always less than 2.0, satisfying for various targets referred to Radiation Therapy Oncology Group (RTOG) SRS criteria. In conclusion, this approach by physical lattice structure could be a useful radiosurgical plan without restrictions in the various tumor shapes and the different modality techniques such as linac and GK for SRS.